add jpg image.

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@303 bbd45198-f89e-11dd-88c7-29a3b14d5316

rtgui/common/image_jpg.c

+
+#include <stdio.h>
+#include <stdlib.h>
+#include "jpeg/jpeglib.h"
+
+#include <rtthread.h>
+#include <rtgui/rtgui.h>
+#include <rtgui/rtgui_system.h>
+#include <rtgui/filerw.h>
+#include <rtgui/image_jpeg.h>
+
+static rt_bool_t rtgui_image_jpeg_check(struct rtgui_filerw* file);
+static rt_bool_t rtgui_image_jpeg_load(struct rtgui_image* image, struct rtgui_filerw* file, rt_bool_t load);
+static void rtgui_image_jpeg_unload(struct rtgui_image* image);
+static void rtgui_image_jpeg_blit(struct rtgui_image* image, struct rtgui_dc* dc, struct rtgui_rect* rect);
+
+struct rtgui_jpeg_error_mgr
+{
+	struct jpeg_error_mgr pub;	/* "public" fields */
+};
+
+struct rtgui_image_jpeg
+{
+	rt_bool_t is_loaded;
+
+	struct rtgui_filerw* filerw;
+
+	/* jpeg structure */
+	struct jpeg_decompress_struct cinfo;
+	struct rtgui_jpeg_error_mgr errmgr;
+
+	rt_uint8_t *pixels;
+	rt_uint8_t *line_pixels;
+};
+
+struct rtgui_image_engine rtgui_image_jpeg_engine =
+{
+	"jpeg",
+	{RT_NULL},
+	rtgui_image_jpeg_check,
+	rtgui_image_jpeg_load,
+	rtgui_image_jpeg_unload,
+	rtgui_image_jpeg_blit
+};
+
+#define INPUT_BUFFER_SIZE	4096
+typedef struct {
+	struct jpeg_source_mgr pub;
+
+	struct rtgui_filerw* ctx;
+	rt_uint8_t buffer[INPUT_BUFFER_SIZE];
+} rtgui_jpeg_source_mgr;
+
+/*
+* Initialize source --- called by jpeg_read_header
+* before any data is actually read.
+*/
+static void init_source (j_decompress_ptr cinfo)
+{
+	/* We don't actually need to do anything */
+	return;
+}
+
+/*
+* Fill the input buffer --- called whenever buffer is emptied.
+*/
+static boolean fill_input_buffer (j_decompress_ptr cinfo)
+{
+	rtgui_jpeg_source_mgr * src = (rtgui_jpeg_source_mgr *) cinfo->src;
+	int nbytes;
+
+	nbytes = rtgui_filerw_read(src->ctx, src->buffer, 1, INPUT_BUFFER_SIZE);
+	if (nbytes <= 0)
+	{
+		/* Insert a fake EOI marker */
+		src->buffer[0] = (rt_uint8_t) 0xFF;
+		src->buffer[1] = (rt_uint8_t) JPEG_EOI;
+		nbytes = 2;
+	}
+
+	src->pub.next_input_byte = src->buffer;
+	src->pub.bytes_in_buffer = nbytes;
+
+	return TRUE;
+}
+
+
+/*
+* Skip data --- used to skip over a potentially large amount of
+* uninteresting data (such as an APPn marker).
+*
+* Writers of suspendable-input applications must note that skip_input_data
+* is not granted the right to give a suspension return.  If the skip extends
+* beyond the data currently in the buffer, the buffer can be marked empty so
+* that the next read will cause a fill_input_buffer call that can suspend.
+* Arranging for additional bytes to be discarded before reloading the input
+* buffer is the application writer's problem.
+*/
+static void skip_input_data (j_decompress_ptr cinfo, long num_bytes)
+{
+	rtgui_jpeg_source_mgr * src = (rtgui_jpeg_source_mgr *) cinfo->src;
+
+	/* Just a dumb implementation for now.	Could use fseek() except
+	* it doesn't work on pipes.  Not clear that being smart is worth
+	* any trouble anyway --- large skips are infrequent.
+	*/
+	if (num_bytes > 0)
+	{
+		while (num_bytes > (long) src->pub.bytes_in_buffer)
+		{
+			num_bytes -= (long) src->pub.bytes_in_buffer;
+			(void) src->pub.fill_input_buffer(cinfo);
+			/* note we assume that fill_input_buffer will never
+			* return FALSE, so suspension need not be handled.
+			*/
+		}
+		src->pub.next_input_byte += (size_t) num_bytes;
+		src->pub.bytes_in_buffer -= (size_t) num_bytes;
+	}
+}
+
+/*
+* Terminate source --- called by jpeg_finish_decompress
+* after all data has been read.
+*/
+static void term_source (j_decompress_ptr cinfo)
+{
+	/* We don't actually need to do anything */
+	return;
+}
+
+/*
+* Prepare for input from a stdio stream.
+* The caller must have already opened the stream, and is responsible
+* for closing it after finishing decompression.
+*/
+static void rtgui_jpeg_filerw_src_init(j_decompress_ptr cinfo, struct rtgui_filerw *ctx)
+{
+	rtgui_jpeg_source_mgr *src;
+
+	/* The source object and input buffer are made permanent so that a series
+	* of JPEG images can be read from the same file by calling jpeg_stdio_src
+	* only before the first one.  (If we discarded the buffer at the end of
+	* one image, we'd likely lose the start of the next one.)
+	* This makes it unsafe to use this manager and a different source
+	* manager serially with the same JPEG object.  Caveat programmer.
+	*/
+	if (cinfo->src == NULL) {	/* first time for this JPEG object? */
+		cinfo->src = (struct jpeg_source_mgr *)
+			(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
+			sizeof(rtgui_jpeg_source_mgr));
+		src = (rtgui_jpeg_source_mgr *) cinfo->src;
+	}
+
+	src = (rtgui_jpeg_source_mgr *) cinfo->src;
+	src->pub.init_source = init_source;
+	src->pub.fill_input_buffer = fill_input_buffer;
+	src->pub.skip_input_data = skip_input_data;
+	src->pub.resync_to_restart = jpeg_resync_to_restart; /* use default method */
+	src->pub.term_source = term_source;
+	src->ctx = ctx;
+	src->pub.bytes_in_buffer = 0; /* forces fill_input_buffer on first read */
+	src->pub.next_input_byte = NULL; /* until buffer loaded */
+}
+
+/* get line data of a jpeg image */
+static rt_uint8_t *rtgui_image_get_line(struct rtgui_image* image, int h)
+{
+	struct rtgui_image_jpeg* jpeg;
+	rt_uint8_t *result_ptr;
+
+	JSAMPARRAY buffer;		/* Output row buffer */
+	int row_stride;
+
+	RT_ASSERT(image != RT_NULL);
+	jpeg = (struct rtgui_image_jpeg*) image->data;
+	RT_ASSERT(jpeg != RT_NULL);
+
+	if (h < 0 || h > image->h) return RT_NULL;
+
+	/* if the image is loaded, */
+	if (jpeg->is_loaded == RT_TRUE)
+	{
+		result_ptr = jpeg->pixels + (image->w * sizeof(rtgui_color_t)) * h;
+
+		return result_ptr;
+	}
+
+	if (jpeg->line_pixels == RT_NULL)
+		jpeg->line_pixels = rtgui_malloc(image->w * sizeof(rtgui_color_t));
+
+	row_stride = jpeg->cinfo.output_width * jpeg->cinfo.output_components;
+	buffer = (*jpeg->cinfo.mem->alloc_sarray)
+		((j_common_ptr) &jpeg->cinfo, JPOOL_IMAGE, row_stride, 1);
+
+	/* decompress line data */
+	jpeg->cinfo.output_scanline = h;
+	jpeg_read_scanlines(&jpeg->cinfo, buffer, (JDIMENSION) 1);
+
+	/* copy pixels memory */
+	{
+		int index;
+		rtgui_color_t *ptr;
+
+		ptr = (rtgui_color_t*)jpeg->line_pixels;
+		for (index = 0; index < image->w; index ++)
+			ptr[index] = RTGUI_ARGB(0, buffer[0][index*3], buffer[0][index*3+1], buffer[0][index*3+2]);
+	}
+
+	return jpeg->line_pixels;
+}
+
+static rt_bool_t rtgui_image_jpeg_loadall(struct rtgui_image* image)
+{
+	struct rtgui_image_jpeg* jpeg;
+	rt_uint8_t* line_ptr;
+	JSAMPARRAY buffer;		/* Output row buffer */
+	int row_stride;
+
+	jpeg = (struct rtgui_image_jpeg*) image->data;
+	RT_ASSERT(jpeg != RT_NULL);
+
+	/* already load */
+	if (jpeg->pixels != RT_NULL) return RT_TRUE;
+
+	/* allocate all pixels */
+	jpeg->pixels = rtgui_malloc(image->h * image->w * sizeof(rtgui_color_t));
+	if (jpeg->pixels == RT_NULL) return RT_FALSE;
+
+	/* reset scan line to zero */
+	jpeg->cinfo.output_scanline = 0;
+	line_ptr = jpeg->pixels;
+
+	row_stride = jpeg->cinfo.output_width * jpeg->cinfo.output_components;
+	buffer = (*jpeg->cinfo.mem->alloc_sarray)
+		((j_common_ptr) &jpeg->cinfo, JPOOL_IMAGE, row_stride, 1);
+
+	/* decompress all pixels */
+	while (jpeg->cinfo.output_scanline < jpeg->cinfo.output_height)
+	{
+		/* jpeg_read_scanlines expects an array of pointers to scanlines.
+		* Here the array is only one element long, but you could ask for
+		* more than one scanline at a time if that's more convenient.
+		*/
+		(void) jpeg_read_scanlines(&jpeg->cinfo, buffer, 1);
+
+		/* copy pixels memory */
+		{
+			int index;
+			rtgui_color_t *ptr;
+
+			ptr = (rtgui_color_t*)line_ptr;
+			for (index = 0; index < image->w; index ++)
+				ptr[index] = RTGUI_ARGB(0, buffer[0][index*3], buffer[0][index*3+1], buffer[0][index*3+2]);
+		}
+
+		/* move to next line */
+		line_ptr += image->w * sizeof(rtgui_color_t);
+	}
+
+	/* decompress done */
+	rtgui_filerw_close(jpeg->filerw);
+	jpeg_finish_decompress(&jpeg->cinfo);
+
+	jpeg->is_loaded = RT_TRUE;
+	return RT_TRUE;
+}
+
+void rtgui_image_jpeg_init()
+{
+	/* register jpeg on image system */
+	rtgui_image_register_engine(&rtgui_image_jpeg_engine);
+}
+
+static void my_error_exit(j_common_ptr cinfo)
+{
+}
+
+static void output_no_message(j_common_ptr cinfo)
+{
+	/* do nothing */
+}
+
+static rt_bool_t rtgui_image_jpeg_load(struct rtgui_image* image, struct rtgui_filerw* file, rt_bool_t load)
+{
+	struct rtgui_image_jpeg* jpeg;
+
+	jpeg = (struct rtgui_image_jpeg*) rtgui_malloc(sizeof(struct rtgui_image_jpeg));
+	if (jpeg == RT_NULL) return RT_FALSE;
+
+	jpeg->filerw = file;
+
+	/* read file header */
+	/* Create a decompression structure and load the JPEG header */
+	jpeg->cinfo.err = jpeg_std_error(&jpeg->errmgr.pub);
+	jpeg->errmgr.pub.error_exit = my_error_exit;
+	jpeg->errmgr.pub.output_message = output_no_message;
+
+	jpeg_create_decompress(&jpeg->cinfo);
+	rtgui_jpeg_filerw_src_init(&jpeg->cinfo, jpeg->filerw);
+	(void)jpeg_read_header(&jpeg->cinfo, TRUE);
+
+	image->w = jpeg->cinfo.image_width;
+	image->h = jpeg->cinfo.image_height;
+
+	/* set image private data and engine */
+	image->data = jpeg;
+	image->engine = &rtgui_image_jpeg_engine;
+
+	/* start decompression */
+	(void) jpeg_start_decompress(&jpeg->cinfo);
+
+	jpeg->cinfo.out_color_space = JCS_RGB;
+	jpeg->cinfo.quantize_colors = FALSE;
+	/* use fast jpeg */
+	jpeg->cinfo.scale_num	= 1;
+	jpeg->cinfo.scale_denom = 1;
+	jpeg->cinfo.dct_method = JDCT_FASTEST;
+	jpeg->cinfo.do_fancy_upsampling = FALSE;
+
+	jpeg->pixels = RT_NULL;
+	jpeg->is_loaded = RT_FALSE;
+
+	/* allocate line pixels */
+	jpeg->line_pixels = rtgui_malloc(image->w * sizeof(rtgui_color_t));
+	if (jpeg->line_pixels == RT_NULL)
+	{
+		/* no memory */
+		jpeg_finish_decompress(&jpeg->cinfo);
+		rt_free(jpeg);
+
+		return RT_FALSE;
+	}
+
+	if (load == RT_TRUE) rtgui_image_jpeg_loadall(image);
+
+	/* create jpeg image successful */
+	return RT_TRUE;
+}
+
+
+static void rtgui_image_jpeg_unload(struct rtgui_image* image)
+{
+	if (image != RT_NULL)
+	{
+		struct rtgui_image_jpeg* jpeg;
+
+		jpeg = (struct rtgui_image_jpeg*) image->data;
+		RT_ASSERT(jpeg != RT_NULL);
+
+		if (jpeg->is_loaded == RT_TRUE)
+			rtgui_free(jpeg->pixels);
+		if (jpeg->line_pixels != RT_NULL) rtgui_free(jpeg->line_pixels);
+
+		if (jpeg->is_loaded != RT_TRUE)
+		{
+			rtgui_filerw_close(jpeg->filerw);
+			jpeg_finish_decompress(&jpeg->cinfo);
+		}
+		rt_free(jpeg);
+	}
+}
+
+static void rtgui_image_jpeg_blit(struct rtgui_image* image, struct rtgui_dc* dc, struct rtgui_rect* rect)
+{
+	rt_uint16_t x, y;
+	rtgui_color_t* ptr;
+	rtgui_color_t foreground;
+	struct rtgui_image_jpeg* jpeg;
+
+	RT_ASSERT(image != RT_NULL && dc != RT_NULL && rect != RT_NULL);
+
+	jpeg = (struct rtgui_image_jpeg*) image->data;
+	RT_ASSERT(jpeg != RT_NULL);
+
+	/* save foreground color */
+	foreground = rtgui_dc_get_color(dc);
+
+	if (jpeg->pixels != RT_NULL)
+	{
+		ptr = (rtgui_color_t*) jpeg->pixels;
+
+		/* draw each point within dc */
+		for (y = 0; y < image->h; y ++)
+		{
+			for (x = 0; x < image->w; x++)
+			{
+				/* not alpha */
+				if ((*ptr >> 24) != 255)
+				{
+					rtgui_dc_set_color(dc, *ptr);
+					rtgui_dc_draw_point(dc, x + rect->x1, y + rect->y1);
+				}
+
+				/* move to next color buffer */
+				ptr ++;
+			}
+		}
+	}
+	else 
+	{
+		/* seek to the begin of file */
+		rtgui_filerw_seek(jpeg->filerw, 0, SEEK_SET);
+
+		/* decompress line and line */
+		for (y = 0; y < image->h; y ++)
+		{
+			ptr = (rtgui_color_t*)rtgui_image_get_line(image, y);
+			for (x = 0; x < image->w; x++)
+			{
+				/* not alpha */
+				if ((*ptr >> 24) != 255)
+				{
+					rtgui_dc_set_color(dc, *ptr);
+					rtgui_dc_draw_point(dc, x + rect->x1, y + rect->y1);
+				}
+
+				/* move to next color buffer */
+				ptr ++;
+			}
+		}
+	}
+
+	/* restore foreground */
+	rtgui_dc_set_color(dc, foreground);
+}
+
+static rt_bool_t rtgui_image_jpeg_check(struct rtgui_filerw* file)
+{
+	int start;
+	rt_bool_t is_JPG;
+	int in_scan;
+	rt_uint8_t magic[4];
+
+	if (file == RT_NULL) return RT_FALSE; /* open file failed */
+
+	start = rtgui_filerw_tell(file);
+	is_JPG = RT_FALSE;
+	in_scan = 0;
+
+	/* seek to the begining of file */
+	rtgui_filerw_seek(file, 0, SEEK_SET);
+		
+	if ( rtgui_filerw_read(file, magic, 2, 1) ) {
+		if ( (magic[0] == 0xFF) && (magic[1] == 0xD8) ) {
+			is_JPG = RT_TRUE;
+			while (is_JPG == RT_TRUE) {
+				if(rtgui_filerw_read(file, magic, 1, 2) != 2) {
+					is_JPG = RT_FALSE;
+				} else if( (magic[0] != 0xFF) && (in_scan == 0) ) {
+					is_JPG = RT_FALSE;
+				} else if( (magic[0] != 0xFF) || (magic[1] == 0xFF) ) {
+					/* Extra padding in JPEG (legal) */
+					/* or this is data and we are scanning */
+					rtgui_filerw_seek(file, -1, SEEK_CUR);
+				} else if(magic[1] == 0xD9) {
+					/* Got to end of good JPEG */
+					break;
+				} else if( (in_scan == 1) && (magic[1] == 0x00) ) {
+					/* This is an encoded 0xFF within the data */
+				} else if( (magic[1] >= 0xD0) && (magic[1] < 0xD9) ) {
+					/* These have nothing else */
+				} else if(rtgui_filerw_read(file, magic+2, 1, 2) != 2) {
+					is_JPG = RT_FALSE;
+				} else {
+					/* Yes, it's big-endian */
+					rt_uint32_t start;
+					rt_uint32_t size;
+					rt_uint32_t end;
+					start = rtgui_filerw_tell(file);
+					size = (magic[2] << 8) + magic[3];
+					end = rtgui_filerw_seek(file, size-2, SEEK_CUR);
+					if ( end != start + size - 2 ) is_JPG = RT_FALSE;
+					if ( magic[1] == 0xDA ) {
+						/* Now comes the actual JPEG meat */
+						/* It is a JPEG. */
+						break;
+					}
+				}
+			}
+		}
+	}
+	rtgui_filerw_seek(file, start, SEEK_SET);
+
+	return is_JPG;
+}
+

rtgui/common/jpeg/Makefile.am

+## Process this file with automake to produce Makefile.in
+#
+#  Automake Makefile for the JPEG library
+#
+#  This file is written by Bob Friesenhahn, Guido Vollbeding
+#
+
+# Sources to build library
+LIBSOURCES = jaricom.c jcapimin.c jcapistd.c jcarith.c jccoefct.c jccolor.c \
+        jcdctmgr.c jchuff.c jcinit.c jcmainct.c jcmarker.c jcmaster.c \
+        jcomapi.c jcparam.c jcprepct.c jcsample.c jctrans.c jdapimin.c \
+        jdapistd.c jdarith.c jdatadst.c jdatasrc.c jdcoefct.c jdcolor.c \
+        jddctmgr.c jdhuff.c jdinput.c jdmainct.c jdmarker.c jdmaster.c \
+        jdmerge.c jdpostct.c jdsample.c jdtrans.c jerror.c jfdctflt.c \
+        jfdctfst.c jfdctint.c jidctflt.c jidctfst.c jidctint.c jquant1.c \
+        jquant2.c jutils.c jmemmgr.c @MEMORYMGR@.c
+
+# System dependent sources
+SYSDEPSOURCES = jmemansi.c jmemname.c jmemnobs.c jmemdos.c jmemmac.c
+
+# Headers which are installed to support the library
+INSTINCLUDES  = jerror.h jmorecfg.h jpeglib.h
+
+# Headers which are not installed
+OTHERINCLUDES = cderror.h cdjpeg.h jdct.h jinclude.h jmemsys.h jpegint.h \
+        jversion.h transupp.h
+
+# Manual pages (Automake uses 'MANS' for itself)
+DISTMANS= cjpeg.1 djpeg.1 jpegtran.1 rdjpgcom.1 wrjpgcom.1
+
+# Other documentation files
+DOCS= README install.txt usage.txt wizard.txt example.c libjpeg.txt \
+        structure.txt coderules.txt filelist.txt change.log
+
+# Makefiles for various systems
+MKFILES= configure Makefile.in makefile.ansi makefile.unix makefile.bcc \
+        makefile.mc6 makefile.dj makefile.wat makefile.vc makejdsw.vc6 \
+        makeadsw.vc6 makejdep.vc6 makejdsp.vc6 makejmak.vc6 makecdep.vc6 \
+        makecdsp.vc6 makecmak.vc6 makeddep.vc6 makeddsp.vc6 makedmak.vc6 \
+        maketdep.vc6 maketdsp.vc6 maketmak.vc6 makerdep.vc6 makerdsp.vc6 \
+        makermak.vc6 makewdep.vc6 makewdsp.vc6 makewmak.vc6 makejsln.vc9 \
+        makeasln.vc9 makejvcp.vc9 makecvcp.vc9 makedvcp.vc9 maketvcp.vc9 \
+        makervcp.vc9 makewvcp.vc9 makeproj.mac makcjpeg.st makdjpeg.st \
+        makljpeg.st maktjpeg.st makefile.manx makefile.sas makefile.mms \
+        makefile.vms makvms.opt
+
+# Configuration files
+CONFIGFILES= jconfig.cfg jconfig.bcc jconfig.mc6 jconfig.dj jconfig.wat \
+        jconfig.vc jconfig.mac jconfig.st jconfig.manx jconfig.sas \
+        jconfig.vms
+
+# Support scripts for configure
+CONFIGUREFILES= config.guess config.sub install-sh ltmain.sh depcomp missing
+
+# Miscellaneous support files
+OTHERFILES= jconfig.txt ckconfig.c ansi2knr.c ansi2knr.1 jmemdosa.asm \
+        libjpeg.map
+
+# Test support files
+TESTFILES= testorig.jpg testimg.ppm testimg.bmp testimg.jpg testprog.jpg \
+        testimgp.jpg
+
+# libtool libraries to build
+lib_LTLIBRARIES = libjpeg.la
+
+# Library sources for libjpeg.la
+libjpeg_la_SOURCES = $(LIBSOURCES)
+
+# LDFLAGS for libjpeg.la
+libjpeg_la_LDFLAGS = -no-undefined \
+        -version-info $(JPEG_LIB_VERSION)
+
+if HAVE_LD_VERSION_SCRIPT
+  libjpeg_la_LDFLAGS += -Wl,--version-script=$(srcdir)/libjpeg.map
+endif
+
+# Executables to build
+bin_PROGRAMS = cjpeg djpeg jpegtran rdjpgcom wrjpgcom
+
+# Executable sources & libs
+cjpeg_SOURCES    = cjpeg.c rdppm.c rdgif.c rdtarga.c rdrle.c rdbmp.c \
+        rdswitch.c cdjpeg.c
+cjpeg_LDADD      = libjpeg.la
+djpeg_SOURCES    = djpeg.c wrppm.c wrgif.c wrtarga.c wrrle.c wrbmp.c \
+        rdcolmap.c cdjpeg.c
+djpeg_LDADD      = libjpeg.la
+jpegtran_SOURCES = jpegtran.c rdswitch.c cdjpeg.c transupp.c
+jpegtran_LDADD   = libjpeg.la
+rdjpgcom_SOURCES = rdjpgcom.c
+wrjpgcom_SOURCES = wrjpgcom.c
+
+# Manual pages to install
+man_MANS = $(DISTMANS)
+
+# Headers to install
+include_HEADERS = $(INSTINCLUDES)
+
+# Other distributed headers
+noinst_HEADERS = $(OTHERINCLUDES)
+
+# Other distributed files
+EXTRA_DIST =  $(DOCS) $(DISTMANS) $(MKFILES) $(CONFIGFILES) $(SYSDEPSOURCES) \
+        $(OTHERFILES) $(TESTFILES)
+
+# Files to be cleaned
+CLEANFILES = testout.ppm testout.bmp testout.jpg testoutp.ppm testoutp.jpg \
+        testoutt.jpg
+
+# Install jconfig.h
+install-data-local:
+	$(mkinstalldirs) $(DESTDIR)$(includedir)
+	$(INSTALL_HEADER) jconfig.h $(DESTDIR)$(includedir)/jconfig.h
+
+# Uninstall jconfig.h
+uninstall-local:
+	rm -f $(DESTDIR)$(includedir)/jconfig.h
+
+# Run tests
+test: check-local
+check-local:
+	$(RM) testout*
+	./djpeg -dct int -ppm -outfile testout.ppm  $(srcdir)/testorig.jpg
+	./djpeg -dct int -bmp -colors 256 -outfile testout.bmp  $(srcdir)/testorig.jpg
+	./cjpeg -dct int -outfile testout.jpg  $(srcdir)/testimg.ppm
+	./djpeg -dct int -ppm -outfile testoutp.ppm $(srcdir)/testprog.jpg
+	./cjpeg -dct int -progressive -opt -outfile testoutp.jpg $(srcdir)/testimg.ppm
+	./jpegtran -outfile testoutt.jpg $(srcdir)/testprog.jpg
+	cmp $(srcdir)/testimg.ppm testout.ppm
+	cmp $(srcdir)/testimg.bmp testout.bmp
+	cmp $(srcdir)/testimg.jpg testout.jpg
+	cmp $(srcdir)/testimg.ppm testoutp.ppm
+	cmp $(srcdir)/testimgp.jpg testoutp.jpg
+	cmp $(srcdir)/testorig.jpg testoutt.jpg

rtgui/common/jpeg/README

+The Independent JPEG Group's JPEG software
+==========================================
+
+README for release 7 of 27-Jun-2009
+===================================
+
+This distribution contains the seventh public release of the Independent JPEG
+Group's free JPEG software.  You are welcome to redistribute this software and
+to use it for any purpose, subject to the conditions under LEGAL ISSUES, below.
+
+This software is the work of Tom Lane, Guido Vollbeding, Philip Gladstone,
+Bill Allombert, Jim Boucher, Lee Crocker, Bob Friesenhahn, Ben Jackson,
+Julian Minguillon, Luis Ortiz, George Phillips, Davide Rossi, Ge' Weijers,
+and other members of the Independent JPEG Group.
+
+IJG is not affiliated with the official ISO JPEG standards committee.
+
+
+DOCUMENTATION ROADMAP
+=====================
+
+This file contains the following sections:
+
+OVERVIEW            General description of JPEG and the IJG software.
+LEGAL ISSUES        Copyright, lack of warranty, terms of distribution.
+REFERENCES          Where to learn more about JPEG.
+ARCHIVE LOCATIONS   Where to find newer versions of this software.
+ACKNOWLEDGMENTS     Special thanks.
+FILE FORMAT WARS    Software *not* to get.
+TO DO               Plans for future IJG releases.
+
+Other documentation files in the distribution are:
+
+User documentation:
+  install.txt       How to configure and install the IJG software.
+  usage.txt         Usage instructions for cjpeg, djpeg, jpegtran,
+                    rdjpgcom, and wrjpgcom.
+  *.1               Unix-style man pages for programs (same info as usage.txt).
+  wizard.txt        Advanced usage instructions for JPEG wizards only.
+  change.log        Version-to-version change highlights.
+Programmer and internal documentation:
+  libjpeg.txt       How to use the JPEG library in your own programs.
+  example.c         Sample code for calling the JPEG library.
+  structure.txt     Overview of the JPEG library's internal structure.
+  filelist.txt      Road map of IJG files.
+  coderules.txt     Coding style rules --- please read if you contribute code.
+
+Please read at least the files install.txt and usage.txt.  Some information
+can also be found in the JPEG FAQ (Frequently Asked Questions) article.  See
+ARCHIVE LOCATIONS below to find out where to obtain the FAQ article.
+
+If you want to understand how the JPEG code works, we suggest reading one or
+more of the REFERENCES, then looking at the documentation files (in roughly
+the order listed) before diving into the code.
+
+
+OVERVIEW
+========
+
+This package contains C software to implement JPEG image encoding, decoding,
+and transcoding.  JPEG (pronounced "jay-peg") is a standardized compression
+method for full-color and gray-scale images.
+
+This software implements JPEG baseline, extended-sequential, and progressive
+compression processes.  Provision is made for supporting all variants of these
+processes, although some uncommon parameter settings aren't implemented yet.
+We have made no provision for supporting the hierarchical or lossless
+processes defined in the standard.
+
+We provide a set of library routines for reading and writing JPEG image files,
+plus two sample applications "cjpeg" and "djpeg", which use the library to
+perform conversion between JPEG and some other popular image file formats.
+The library is intended to be reused in other applications.
+
+In order to support file conversion and viewing software, we have included
+considerable functionality beyond the bare JPEG coding/decoding capability;
+for example, the color quantization modules are not strictly part of JPEG
+decoding, but they are essential for output to colormapped file formats or
+colormapped displays.  These extra functions can be compiled out of the
+library if not required for a particular application.
+
+We have also included "jpegtran", a utility for lossless transcoding between
+different JPEG processes, and "rdjpgcom" and "wrjpgcom", two simple
+applications for inserting and extracting textual comments in JFIF files.
+
+The emphasis in designing this software has been on achieving portability and
+flexibility, while also making it fast enough to be useful.  In particular,
+the software is not intended to be read as a tutorial on JPEG.  (See the
+REFERENCES section for introductory material.)  Rather, it is intended to
+be reliable, portable, industrial-strength code.  We do not claim to have
+achieved that goal in every aspect of the software, but we strive for it.
+
+We welcome the use of this software as a component of commercial products.
+No royalty is required, but we do ask for an acknowledgement in product
+documentation, as described under LEGAL ISSUES.
+
+
+LEGAL ISSUES
+============
+
+In plain English:
+
+1. We don't promise that this software works.  (But if you find any bugs,
+   please let us know!)
+2. You can use this software for whatever you want.  You don't have to pay us.
+3. You may not pretend that you wrote this software.  If you use it in a
+   program, you must acknowledge somewhere in your documentation that
+   you've used the IJG code.
+
+In legalese:
+
+The authors make NO WARRANTY or representation, either express or implied,
+with respect to this software, its quality, accuracy, merchantability, or
+fitness for a particular purpose.  This software is provided "AS IS", and you,
+its user, assume the entire risk as to its quality and accuracy.
+
+This software is copyright (C) 1991-2009, Thomas G. Lane, Guido Vollbeding.
+All Rights Reserved except as specified below.
+
+Permission is hereby granted to use, copy, modify, and distribute this
+software (or portions thereof) for any purpose, without fee, subject to these
+conditions:
+(1) If any part of the source code for this software is distributed, then this
+README file must be included, with this copyright and no-warranty notice
+unaltered; and any additions, deletions, or changes to the original files
+must be clearly indicated in accompanying documentation.
+(2) If only executable code is distributed, then the accompanying
+documentation must state that "this software is based in part on the work of
+the Independent JPEG Group".
+(3) Permission for use of this software is granted only if the user accepts
+full responsibility for any undesirable consequences; the authors accept
+NO LIABILITY for damages of any kind.
+
+These conditions apply to any software derived from or based on the IJG code,
+not just to the unmodified library.  If you use our work, you ought to
+acknowledge us.
+
+Permission is NOT granted for the use of any IJG author's name or company name
+in advertising or publicity relating to this software or products derived from
+it.  This software may be referred to only as "the Independent JPEG Group's
+software".
+
+We specifically permit and encourage the use of this software as the basis of
+commercial products, provided that all warranty or liability claims are
+assumed by the product vendor.
+
+
+ansi2knr.c is included in this distribution by permission of L. Peter Deutsch,
+sole proprietor of its copyright holder, Aladdin Enterprises of Menlo Park, CA.
+ansi2knr.c is NOT covered by the above copyright and conditions, but instead
+by the usual distribution terms of the Free Software Foundation; principally,
+that you must include source code if you redistribute it.  (See the file
+ansi2knr.c for full details.)  However, since ansi2knr.c is not needed as part
+of any program generated from the IJG code, this does not limit you more than
+the foregoing paragraphs do.
+
+The Unix configuration script "configure" was produced with GNU Autoconf.
+It is copyright by the Free Software Foundation but is freely distributable.
+The same holds for its supporting scripts (config.guess, config.sub,
+ltmain.sh).  Another support script, install-sh, is copyright by X Consortium
+but is also freely distributable.
+
+The IJG distribution formerly included code to read and write GIF files.
+To avoid entanglement with the Unisys LZW patent, GIF reading support has
+been removed altogether, and the GIF writer has been simplified to produce
+"uncompressed GIFs".  This technique does not use the LZW algorithm; the
+resulting GIF files are larger than usual, but are readable by all standard
+GIF decoders.
+
+We are required to state that
+    "The Graphics Interchange Format(c) is the Copyright property of
+    CompuServe Incorporated.  GIF(sm) is a Service Mark property of
+    CompuServe Incorporated."
+
+
+REFERENCES
+==========
+
+We recommend reading one or more of these references before trying to
+understand the innards of the JPEG software.
+
+The best short technical introduction to the JPEG compression algorithm is
+	Wallace, Gregory K.  "The JPEG Still Picture Compression Standard",
+	Communications of the ACM, April 1991 (vol. 34 no. 4), pp. 30-44.
+(Adjacent articles in that issue discuss MPEG motion picture compression,
+applications of JPEG, and related topics.)  If you don't have the CACM issue
+handy, a PostScript file containing a revised version of Wallace's article is
+available at http://www.ijg.org/files/wallace.ps.gz.  The file (actually
+a preprint for an article that appeared in IEEE Trans. Consumer Electronics)
+omits the sample images that appeared in CACM, but it includes corrections
+and some added material.  Note: the Wallace article is copyright ACM and IEEE,
+and it may not be used for commercial purposes.
+
+A somewhat less technical, more leisurely introduction to JPEG can be found in
+"The Data Compression Book" by Mark Nelson and Jean-loup Gailly, published by
+M&T Books (New York), 2nd ed. 1996, ISBN 1-55851-434-1.  This book provides
+good explanations and example C code for a multitude of compression methods
+including JPEG.  It is an excellent source if you are comfortable reading C
+code but don't know much about data compression in general.  The book's JPEG
+sample code is far from industrial-strength, but when you are ready to look
+at a full implementation, you've got one here...
+
+The best currently available description of JPEG is the textbook "JPEG Still
+Image Data Compression Standard" by William B. Pennebaker and Joan L.
+Mitchell, published by Van Nostrand Reinhold, 1993, ISBN 0-442-01272-1.
+Price US$59.95, 638 pp.  The book includes the complete text of the ISO JPEG
+standards (DIS 10918-1 and draft DIS 10918-2).
+Although this is by far the most detailed and comprehensive exposition of
+JPEG publicly available, we point out that it is still missing an explanation
+of the most essential properties and algorithms of the underlying DCT
+technology.
+If you think that you know about DCT-based JPEG after reading this book,
+then you are in delusion.  The real fundamentals and corresponding potential
+of DCT-based JPEG are not publicly known so far, and that is the reason for
+all the mistaken developments taking place in the image coding domain.
+
+The original JPEG standard is divided into two parts, Part 1 being the actual
+specification, while Part 2 covers compliance testing methods.  Part 1 is
+titled "Digital Compression and Coding of Continuous-tone Still Images,
+Part 1: Requirements and guidelines" and has document numbers ISO/IEC IS
+10918-1, ITU-T T.81.  Part 2 is titled "Digital Compression and Coding of
+Continuous-tone Still Images, Part 2: Compliance testing" and has document
+numbers ISO/IEC IS 10918-2, ITU-T T.83.
+
+The JPEG standard does not specify all details of an interchangeable file
+format.  For the omitted details we follow the "JFIF" conventions, revision
+1.02.  A copy of the JFIF spec is available from:
+	Literature Department
+	C-Cube Microsystems, Inc.
+	1778 McCarthy Blvd.
+	Milpitas, CA 95035
+	phone (408) 944-6300,  fax (408) 944-6314
+A PostScript version of this document is available at
+http://www.ijg.org/files/jfif.ps.gz.  There is also a plain text version at
+http://www.ijg.org/files/jfif.txt.gz, but it is missing the figures.
+
+The TIFF 6.0 file format specification can be obtained by FTP from
+ftp://ftp.sgi.com/graphics/tiff/TIFF6.ps.gz.  The JPEG incorporation scheme
+found in the TIFF 6.0 spec of 3-June-92 has a number of serious problems.
+IJG does not recommend use of the TIFF 6.0 design (TIFF Compression tag 6).
+Instead, we recommend the JPEG design proposed by TIFF Technical Note #2
+(Compression tag 7).  Copies of this Note can be obtained from
+http://www.ijg.org/files/.  It is expected that the next revision
+of the TIFF spec will replace the 6.0 JPEG design with the Note's design.
+Although IJG's own code does not support TIFF/JPEG, the free libtiff library
+uses our library to implement TIFF/JPEG per the Note.
+
+
+ARCHIVE LOCATIONS
+=================
+
+The "official" archive site for this software is www.ijg.org.
+The most recent released version can always be found there in
+directory "files".  This particular version will be archived as
+http://www.ijg.org/files/jpegsrc.v7.tar.gz, and in Windows-compatible
+"zip" archive format as http://www.ijg.org/files/jpegsr7.zip.
+
+The JPEG FAQ (Frequently Asked Questions) article is a source of some
+general information about JPEG.
+It is available on the World Wide Web at http://www.faqs.org/faqs/jpeg-faq/
+and other news.answers archive sites, including the official news.answers
+archive at rtfm.mit.edu: ftp://rtfm.mit.edu/pub/usenet/news.answers/jpeg-faq/.
+If you don't have Web or FTP access, send e-mail to mail-server@rtfm.mit.edu
+with body
+	send usenet/news.answers/jpeg-faq/part1
+	send usenet/news.answers/jpeg-faq/part2
+
+
+ACKNOWLEDGMENTS
+===============
+
+Thank to Juergen Bruder of the Georg-Cantor-Organization at the
+Martin-Luther-University Halle for providing me with a copy of the common
+DCT algorithm article, only to find out that I had come to the same result
+in a more direct and comprehensible way with a more generative approach.
+
+Thank to Istvan Sebestyen and Joan L. Mitchell for inviting me to the
+ITU JPEG (Study Group 16) meeting in Geneva, Switzerland.
+
+Thank to Thomas Wiegand and Gary Sullivan for inviting me to the
+Joint Video Team (MPEG & ITU) meeting in Geneva, Switzerland.
+
+Thank to John Korejwa and Massimo Ballerini for inviting me to
+fruitful consultations in Boston, MA and Milan, Italy.
+
+Thank to Hendrik Elstner, Roland Fassauer, and Simone Zuck for
+corresponding business development.
+
+Thank to Nico Zschach and Dirk Stelling of the technical support team
+at the Digital Images company in Halle for providing me with extra
+equipment for configuration tests.
+
+Thank to Richard F. Lyon (then of Foveon Inc.) for fruitful
+communication about JPEG configuration in Sigma Photo Pro software.
+
+Last but not least special thank to Thomas G. Lane for the original
+design and development of this singular software package.
+
+
+FILE FORMAT WARS
+================
+
+The ISO JPEG standards committee actually promotes different formats like
+JPEG-2000 or JPEG-XR which are incompatible with original DCT-based JPEG
+and which are based on faulty technologies.  IJG therefore does not and
+will not support such momentary mistakes (see REFERENCES).
+We have little or no sympathy for the promotion of these formats.  Indeed,
+one of the original reasons for developing this free software was to help
+force convergence on common, interoperable format standards for JPEG files.
+Don't use an incompatible file format!
+(In any case, our decoder will remain capable of reading existing JPEG
+image files indefinitely.)
+
+
+TO DO
+=====
+
+v7 is basically just a necessary interim release, paving the way for a
+major breakthrough in image coding technology with the next v8 package
+which is scheduled for release in the year 2010.
+
+Please send bug reports, offers of help, etc. to jpeg-info@jpegclub.org.

rtgui/common/jpeg/ansi2knr.1

+.TH ANSI2KNR 1 "19 Jan 1996"
+.SH NAME
+ansi2knr \- convert ANSI C to Kernighan & Ritchie C
+.SH SYNOPSIS
+.I ansi2knr
+[--varargs] input_file [output_file]
+.SH DESCRIPTION
+If no output_file is supplied, output goes to stdout.
+.br
+There are no error messages.
+.sp
+.I ansi2knr
+recognizes function definitions by seeing a non-keyword identifier at the left
+margin, followed by a left parenthesis, with a right parenthesis as the last
+character on the line, and with a left brace as the first token on the
+following line (ignoring possible intervening comments).  It will recognize a
+multi-line header provided that no intervening line ends with a left or right
+brace or a semicolon.  These algorithms ignore whitespace and comments, except
+that the function name must be the first thing on the line.
+.sp
+The following constructs will confuse it:
+.br
+     - Any other construct that starts at the left margin and follows the
+above syntax (such as a macro or function call).
+.br
+     - Some macros that tinker with the syntax of the function header.
+.sp
+The --varargs switch is obsolete, and is recognized only for
+backwards compatibility.  The present version of
+.I ansi2knr
+will always attempt to convert a ... argument to va_alist and va_dcl.
+.SH AUTHOR
+L. Peter Deutsch <ghost@aladdin.com> wrote the original ansi2knr and
+continues to maintain the current version; most of the code in the current
+version is his work.  ansi2knr also includes contributions by Francois
+Pinard <pinard@iro.umontreal.ca> and Jim Avera <jima@netcom.com>.

rtgui/common/jpeg/cderror.h

+/*
+ * cderror.h
+ *
+ * Copyright (C) 1994-1997, Thomas G. Lane.
+ * This file is part of the Independent JPEG Group's software.
+ * For conditions of distribution and use, see the accompanying README file.
+ *
+ * This file defines the error and message codes for the cjpeg/djpeg
+ * applications.  These strings are not needed as part of the JPEG library
+ * proper.
+ * Edit this file to add new codes, or to translate the message strings to
+ * some other language.
+ */
+
+/*
+ * To define the enum list of message codes, include this file without
+ * defining macro JMESSAGE.  To create a message string table, include it
+ * again with a suitable JMESSAGE definition (see jerror.c for an example).
+ */
+#ifndef JMESSAGE
+#ifndef CDERROR_H
+#define CDERROR_H
+/* First time through, define the enum list */
+#define JMAKE_ENUM_LIST
+#else
+/* Repeated inclusions of this file are no-ops unless JMESSAGE is defined */
+#define JMESSAGE(code,string)
+#endif /* CDERROR_H */
+#endif /* JMESSAGE */
+
+#ifdef JMAKE_ENUM_LIST
+
+typedef enum {
+
+#define JMESSAGE(code,string)	code ,
+
+#endif /* JMAKE_ENUM_LIST */
+
+JMESSAGE(JMSG_FIRSTADDONCODE=1000, NULL) /* Must be first entry! */
+
+#ifdef BMP_SUPPORTED
+JMESSAGE(JERR_BMP_BADCMAP, "Unsupported BMP colormap format")
+JMESSAGE(JERR_BMP_BADDEPTH, "Only 8- and 24-bit BMP files are supported")
+JMESSAGE(JERR_BMP_BADHEADER, "Invalid BMP file: bad header length")
+JMESSAGE(JERR_BMP_BADPLANES, "Invalid BMP file: biPlanes not equal to 1")
+JMESSAGE(JERR_BMP_COLORSPACE, "BMP output must be grayscale or RGB")
+JMESSAGE(JERR_BMP_COMPRESSED, "Sorry, compressed BMPs not yet supported")
+JMESSAGE(JERR_BMP_NOT, "Not a BMP file - does not start with BM")
+JMESSAGE(JTRC_BMP, "%ux%u 24-bit BMP image")
+JMESSAGE(JTRC_BMP_MAPPED, "%ux%u 8-bit colormapped BMP image")
+JMESSAGE(JTRC_BMP_OS2, "%ux%u 24-bit OS2 BMP image")
+JMESSAGE(JTRC_BMP_OS2_MAPPED, "%ux%u 8-bit colormapped OS2 BMP image")
+#endif /* BMP_SUPPORTED */
+
+#ifdef GIF_SUPPORTED
+JMESSAGE(JERR_GIF_BUG, "GIF output got confused")
+JMESSAGE(JERR_GIF_CODESIZE, "Bogus GIF codesize %d")
+JMESSAGE(JERR_GIF_COLORSPACE, "GIF output must be grayscale or RGB")
+JMESSAGE(JERR_GIF_IMAGENOTFOUND, "Too few images in GIF file")
+JMESSAGE(JERR_GIF_NOT, "Not a GIF file")
+JMESSAGE(JTRC_GIF, "%ux%ux%d GIF image")
+JMESSAGE(JTRC_GIF_BADVERSION,
+	 "Warning: unexpected GIF version number '%c%c%c'")
+JMESSAGE(JTRC_GIF_EXTENSION, "Ignoring GIF extension block of type 0x%02x")
+JMESSAGE(JTRC_GIF_NONSQUARE, "Caution: nonsquare pixels in input")
+JMESSAGE(JWRN_GIF_BADDATA, "Corrupt data in GIF file")
+JMESSAGE(JWRN_GIF_CHAR, "Bogus char 0x%02x in GIF file, ignoring")
+JMESSAGE(JWRN_GIF_ENDCODE, "Premature end of GIF image")
+JMESSAGE(JWRN_GIF_NOMOREDATA, "Ran out of GIF bits")
+#endif /* GIF_SUPPORTED */
+
+#ifdef PPM_SUPPORTED
+JMESSAGE(JERR_PPM_COLORSPACE, "PPM output must be grayscale or RGB")
+JMESSAGE(JERR_PPM_NONNUMERIC, "Nonnumeric data in PPM file")
+JMESSAGE(JERR_PPM_NOT, "Not a PPM/PGM file")
+JMESSAGE(JTRC_PGM, "%ux%u PGM image")
+JMESSAGE(JTRC_PGM_TEXT, "%ux%u text PGM image")
+JMESSAGE(JTRC_PPM, "%ux%u PPM image")
+JMESSAGE(JTRC_PPM_TEXT, "%ux%u text PPM image")
+#endif /* PPM_SUPPORTED */
+
+#ifdef RLE_SUPPORTED
+JMESSAGE(JERR_RLE_BADERROR, "Bogus error code from RLE library")
+JMESSAGE(JERR_RLE_COLORSPACE, "RLE output must be grayscale or RGB")
+JMESSAGE(JERR_RLE_DIMENSIONS, "Image dimensions (%ux%u) too large for RLE")
+JMESSAGE(JERR_RLE_EMPTY, "Empty RLE file")
+JMESSAGE(JERR_RLE_EOF, "Premature EOF in RLE header")
+JMESSAGE(JERR_RLE_MEM, "Insufficient memory for RLE header")
+JMESSAGE(JERR_RLE_NOT, "Not an RLE file")
+JMESSAGE(JERR_RLE_TOOMANYCHANNELS, "Cannot handle %d output channels for RLE")
+JMESSAGE(JERR_RLE_UNSUPPORTED, "Cannot handle this RLE setup")
+JMESSAGE(JTRC_RLE, "%ux%u full-color RLE file")
+JMESSAGE(JTRC_RLE_FULLMAP, "%ux%u full-color RLE file with map of length %d")
+JMESSAGE(JTRC_RLE_GRAY, "%ux%u grayscale RLE file")
+JMESSAGE(JTRC_RLE_MAPGRAY, "%ux%u grayscale RLE file with map of length %d")
+JMESSAGE(JTRC_RLE_MAPPED, "%ux%u colormapped RLE file with map of length %d")
+#endif /* RLE_SUPPORTED */
+
+#ifdef TARGA_SUPPORTED
+JMESSAGE(JERR_TGA_BADCMAP, "Unsupported Targa colormap format")
+JMESSAGE(JERR_TGA_BADPARMS, "Invalid or unsupported Targa file")
+JMESSAGE(JERR_TGA_COLORSPACE, "Targa output must be grayscale or RGB")
+JMESSAGE(JTRC_TGA, "%ux%u RGB Targa image")
+JMESSAGE(JTRC_TGA_GRAY, "%ux%u grayscale Targa image")
+JMESSAGE(JTRC_TGA_MAPPED, "%ux%u colormapped Targa image")
+#else
+JMESSAGE(JERR_TGA_NOTCOMP, "Targa support was not compiled")
+#endif /* TARGA_SUPPORTED */
+
+JMESSAGE(JERR_BAD_CMAP_FILE,
+	 "Color map file is invalid or of unsupported format")
+JMESSAGE(JERR_TOO_MANY_COLORS,
+	 "Output file format cannot handle %d colormap entries")
+JMESSAGE(JERR_UNGETC_FAILED, "ungetc failed")
+#ifdef TARGA_SUPPORTED
+JMESSAGE(JERR_UNKNOWN_FORMAT,
+	 "Unrecognized input file format --- perhaps you need -targa")
+#else
+JMESSAGE(JERR_UNKNOWN_FORMAT, "Unrecognized input file format")
+#endif
+JMESSAGE(JERR_UNSUPPORTED_FORMAT, "Unsupported output file format")
+
+#ifdef JMAKE_ENUM_LIST
+
+  JMSG_LASTADDONCODE
+} ADDON_MESSAGE_CODE;
+
+#undef JMAKE_ENUM_LIST
+#endif /* JMAKE_ENUM_LIST */
+
+/* Zap JMESSAGE macro so that future re-inclusions do nothing by default */
+#undef JMESSAGE

rtgui/common/jpeg/cdjpeg.c

+/*
+ * cdjpeg.c
+ *
+ * Copyright (C) 1991-1997, Thomas G. Lane.
+ * This file is part of the Independent JPEG Group's software.
+ * For conditions of distribution and use, see the accompanying README file.
+ *
+ * This file contains common support routines used by the IJG application
+ * programs (cjpeg, djpeg, jpegtran).
+ */
+
+#include "cdjpeg.h"		/* Common decls for cjpeg/djpeg applications */
+#include <ctype.h>		/* to declare isupper(), tolower() */
+#ifdef NEED_SIGNAL_CATCHER
+#include <signal.h>		/* to declare signal() */
+#endif
+#ifdef USE_SETMODE
+#include <fcntl.h>		/* to declare setmode()'s parameter macros */
+/* If you have setmode() but not <io.h>, just delete this line: */
+#include <io.h>			/* to declare setmode() */
+#endif
+
+
+/*
+ * Signal catcher to ensure that temporary files are removed before aborting.
+ * NB: for Amiga Manx C this is actually a global routine named _abort();
+ * we put "#define signal_catcher _abort" in jconfig.h.  Talk about bogus...
+ */
+
+#ifdef NEED_SIGNAL_CATCHER
+
+static j_common_ptr sig_cinfo;
+
+void				/* must be global for Manx C */
+signal_catcher (int signum)
+{
+  if (sig_cinfo != NULL) {
+    if (sig_cinfo->err != NULL) /* turn off trace output */
+      sig_cinfo->err->trace_level = 0;
+    jpeg_destroy(sig_cinfo);	/* clean up memory allocation & temp files */
+  }
+  exit(EXIT_FAILURE);
+}
+
+
+GLOBAL(void)
+enable_signal_catcher (j_common_ptr cinfo)
+{
+  sig_cinfo = cinfo;
+#ifdef SIGINT			/* not all systems have SIGINT */
+  signal(SIGINT, signal_catcher);
+#endif
+#ifdef SIGTERM			/* not all systems have SIGTERM */
+  signal(SIGTERM, signal_catcher);
+#endif
+}
+
+#endif
+
+
+/*
+ * Optional progress monitor: display a percent-done figure on stderr.
+ */
+
+#ifdef PROGRESS_REPORT
+
+METHODDEF(void)
+progress_monitor (j_common_ptr cinfo)
+{
+  cd_progress_ptr prog = (cd_progress_ptr) cinfo->progress;
+  int total_passes = prog->pub.total_passes + prog->total_extra_passes;
+  int percent_done = (int) (prog->pub.pass_counter*100L/prog->pub.pass_limit);
+
+  if (percent_done != prog->percent_done) {
+    prog->percent_done = percent_done;
+    if (total_passes > 1) {
+      fprintf(stderr, "\rPass %d/%d: %3d%% ",
+	      prog->pub.completed_passes + prog->completed_extra_passes + 1,
+	      total_passes, percent_done);
+    } else {
+      fprintf(stderr, "\r %3d%% ", percent_done);
+    }
+    fflush(stderr);
+  }
+}
+
+
+GLOBAL(void)
+start_progress_monitor (j_common_ptr cinfo, cd_progress_ptr progress)
+{
+  /* Enable progress display, unless trace output is on */
+  if (cinfo->err->trace_level == 0) {
+    progress->pub.progress_monitor = progress_monitor;
+    progress->completed_extra_passes = 0;
+    progress->total_extra_passes = 0;
+    progress->percent_done = -1;
+    cinfo->progress = &progress->pub;
+  }
+}
+
+
+GLOBAL(void)
+end_progress_monitor (j_common_ptr cinfo)
+{
+  /* Clear away progress display */
+  if (cinfo->err->trace_level == 0) {
+    fprintf(stderr, "\r                \r");
+    fflush(stderr);
+  }
+}
+
+#endif
+
+
+/*
+ * Case-insensitive matching of possibly-abbreviated keyword switches.
+ * keyword is the constant keyword (must be lower case already),
+ * minchars is length of minimum legal abbreviation.
+ */
+
+GLOBAL(boolean)
+keymatch (char * arg, const char * keyword, int minchars)
+{
+  register int ca, ck;
+  register int nmatched = 0;
+
+  while ((ca = *arg++) != '\0') {
+    if ((ck = *keyword++) == '\0')
+      return FALSE;		/* arg longer than keyword, no good */
+    if (isupper(ca))		/* force arg to lcase (assume ck is already) */
+      ca = tolower(ca);
+    if (ca != ck)
+      return FALSE;		/* no good */
+    nmatched++;			/* count matched characters */
+  }
+  /* reached end of argument; fail if it's too short for unique abbrev */
+  if (nmatched < minchars)
+    return FALSE;
+  return TRUE;			/* A-OK */
+}
+
+
+/*
+ * Routines to establish binary I/O mode for stdin and stdout.
+ * Non-Unix systems often require some hacking to get out of text mode.
+ */
+
+GLOBAL(FILE *)
+read_stdin (void)
+{
+  FILE * input_file = stdin;
+
+#ifdef USE_SETMODE		/* need to hack file mode? */
+  setmode(fileno(stdin), O_BINARY);
+#endif
+#ifdef USE_FDOPEN		/* need to re-open in binary mode? */
+  if ((input_file = fdopen(fileno(stdin), READ_BINARY)) == NULL) {
+    fprintf(stderr, "Cannot reopen stdin\n");
+    exit(EXIT_FAILURE);
+  }
+#endif
+  return input_file;
+}
+
+
+GLOBAL(FILE *)
+write_stdout (void)
+{
+  FILE * output_file = stdout;
+
+#ifdef USE_SETMODE		/* need to hack file mode? */
+  setmode(fileno(stdout), O_BINARY);
+#endif
+#ifdef USE_FDOPEN		/* need to re-open in binary mode? */
+  if ((output_file = fdopen(fileno(stdout), WRITE_BINARY)) == NULL) {
+    fprintf(stderr, "Cannot reopen stdout\n");
+    exit(EXIT_FAILURE);
+  }
+#endif
+  return output_file;
+}

rtgui/common/jpeg/cdjpeg.h

+/*
+ * cdjpeg.h
+ *
+ * Copyright (C) 1994-1997, Thomas G. Lane.
+ * This file is part of the Independent JPEG Group's software.
+ * For conditions of distribution and use, see the accompanying README file.
+ *
+ * This file contains common declarations for the sample applications
+ * cjpeg and djpeg.  It is NOT used by the core JPEG library.
+ */
+
+#define JPEG_CJPEG_DJPEG	/* define proper options in jconfig.h */
+#define JPEG_INTERNAL_OPTIONS	/* cjpeg.c,djpeg.c need to see xxx_SUPPORTED */
+#include "jinclude.h"
+#include "jpeglib.h"
+#include "jerror.h"		/* get library error codes too */
+#include "cderror.h"		/* get application-specific error codes */
+
+
+/*
+ * Object interface for cjpeg's source file decoding modules
+ */
+
+typedef struct cjpeg_source_struct * cjpeg_source_ptr;
+
+struct cjpeg_source_struct {
+  JMETHOD(void, start_input, (j_compress_ptr cinfo,
+			      cjpeg_source_ptr sinfo));
+  JMETHOD(JDIMENSION, get_pixel_rows, (j_compress_ptr cinfo,
+				       cjpeg_source_ptr sinfo));
+  JMETHOD(void, finish_input, (j_compress_ptr cinfo,
+			       cjpeg_source_ptr sinfo));
+
+  FILE *input_file;
+
+  JSAMPARRAY buffer;
+  JDIMENSION buffer_height;
+};
+
+
+/*
+ * Object interface for djpeg's output file encoding modules
+ */
+
+typedef struct djpeg_dest_struct * djpeg_dest_ptr;
+
+struct djpeg_dest_struct {
+  /* start_output is called after jpeg_start_decompress finishes.
+   * The color map will be ready at this time, if one is needed.
+   */
+  JMETHOD(void, start_output, (j_decompress_ptr cinfo,
+			       djpeg_dest_ptr dinfo));
+  /* Emit the specified number of pixel rows from the buffer. */
+  JMETHOD(void, put_pixel_rows, (j_decompress_ptr cinfo,
+				 djpeg_dest_ptr dinfo,
+				 JDIMENSION rows_supplied));
+  /* Finish up at the end of the image. */
+  JMETHOD(void, finish_output, (j_decompress_ptr cinfo,
+				djpeg_dest_ptr dinfo));
+
+  /* Target file spec; filled in by djpeg.c after object is created. */
+  FILE * output_file;
+
+  /* Output pixel-row buffer.  Created by module init or start_output.
+   * Width is cinfo->output_width * cinfo->output_components;
+   * height is buffer_height.
+   */
+  JSAMPARRAY buffer;
+  JDIMENSION buffer_height;
+};
+
+
+/*
+ * cjpeg/djpeg may need to perform extra passes to convert to or from
+ * the source/destination file format.  The JPEG library does not know
+ * about these passes, but we'd like them to be counted by the progress
+ * monitor.  We use an expanded progress monitor object to hold the
+ * additional pass count.
+ */
+
+struct cdjpeg_progress_mgr {
+  struct jpeg_progress_mgr pub;	/* fields known to JPEG library */
+  int completed_extra_passes;	/* extra passes completed */
+  int total_extra_passes;	/* total extra */
+  /* last printed percentage stored here to avoid multiple printouts */
+  int percent_done;
+};
+
+typedef struct cdjpeg_progress_mgr * cd_progress_ptr;
+
+
+/* Short forms of external names for systems with brain-damaged linkers. */
+
+#ifdef NEED_SHORT_EXTERNAL_NAMES
+#define jinit_read_bmp		jIRdBMP
+#define jinit_write_bmp		jIWrBMP
+#define jinit_read_gif		jIRdGIF
+#define jinit_write_gif		jIWrGIF
+#define jinit_read_ppm		jIRdPPM
+#define jinit_write_ppm		jIWrPPM
+#define jinit_read_rle		jIRdRLE
+#define jinit_write_rle		jIWrRLE
+#define jinit_read_targa	jIRdTarga
+#define jinit_write_targa	jIWrTarga
+#define read_quant_tables	RdQTables
+#define read_scan_script	RdScnScript
+#define set_quality_ratings     SetQRates
+#define set_quant_slots		SetQSlots
+#define set_sample_factors	SetSFacts
+#define read_color_map		RdCMap
+#define enable_signal_catcher	EnSigCatcher
+#define start_progress_monitor	StProgMon
+#define end_progress_monitor	EnProgMon
+#define read_stdin		RdStdin
+#define write_stdout		WrStdout
+#endif /* NEED_SHORT_EXTERNAL_NAMES */
+
+/* Module selection routines for I/O modules. */
+
+EXTERN(cjpeg_source_ptr) jinit_read_bmp JPP((j_compress_ptr cinfo));
+EXTERN(djpeg_dest_ptr) jinit_write_bmp JPP((j_decompress_ptr cinfo,
+					    boolean is_os2));
+EXTERN(cjpeg_source_ptr) jinit_read_gif JPP((j_compress_ptr cinfo));
+EXTERN(djpeg_dest_ptr) jinit_write_gif JPP((j_decompress_ptr cinfo));
+EXTERN(cjpeg_source_ptr) jinit_read_ppm JPP((j_compress_ptr cinfo));
+EXTERN(djpeg_dest_ptr) jinit_write_ppm JPP((j_decompress_ptr cinfo));
+EXTERN(cjpeg_source_ptr) jinit_read_rle JPP((j_compress_ptr cinfo));
+EXTERN(djpeg_dest_ptr) jinit_write_rle JPP((j_decompress_ptr cinfo));
+EXTERN(cjpeg_source_ptr) jinit_read_targa JPP((j_compress_ptr cinfo));
+EXTERN(djpeg_dest_ptr) jinit_write_targa JPP((j_decompress_ptr cinfo));
+
+/* cjpeg support routines (in rdswitch.c) */
+
+EXTERN(boolean) read_quant_tables JPP((j_compress_ptr cinfo, char * filename,
+				       boolean force_baseline));
+EXTERN(boolean) read_scan_script JPP((j_compress_ptr cinfo, char * filename));
+EXTERN(boolean) set_quality_ratings JPP((j_compress_ptr cinfo, char *arg,
+					 boolean force_baseline));
+EXTERN(boolean) set_quant_slots JPP((j_compress_ptr cinfo, char *arg));
+EXTERN(boolean) set_sample_factors JPP((j_compress_ptr cinfo, char *arg));
+
+/* djpeg support routines (in rdcolmap.c) */
+
+EXTERN(void) read_color_map JPP((j_decompress_ptr cinfo, FILE * infile));
+
+/* common support routines (in cdjpeg.c) */
+
+EXTERN(void) enable_signal_catcher JPP((j_common_ptr cinfo));
+EXTERN(void) start_progress_monitor JPP((j_common_ptr cinfo,
+					 cd_progress_ptr progress));
+EXTERN(void) end_progress_monitor JPP((j_common_ptr cinfo));
+EXTERN(boolean) keymatch JPP((char * arg, const char * keyword, int minchars));
+EXTERN(FILE *) read_stdin JPP((void));
+EXTERN(FILE *) write_stdout JPP((void));
+
+/* miscellaneous useful macros */
+
+#ifdef DONT_USE_B_MODE		/* define mode parameters for fopen() */
+#define READ_BINARY	"r"
+#define WRITE_BINARY	"w"
+#else
+#ifdef VMS			/* VMS is very nonstandard */
+#define READ_BINARY	"rb", "ctx=stm"
+#define WRITE_BINARY	"wb", "ctx=stm"
+#else				/* standard ANSI-compliant case */
+#define READ_BINARY	"rb"
+#define WRITE_BINARY	"wb"
+#endif
+#endif
+
+#ifndef EXIT_FAILURE		/* define exit() codes if not provided */
+#define EXIT_FAILURE  1
+#endif
+#ifndef EXIT_SUCCESS
+#ifdef VMS
+#define EXIT_SUCCESS  1		/* VMS is very nonstandard */
+#else
+#define EXIT_SUCCESS  0
+#endif
+#endif
+#ifndef EXIT_WARNING
+#ifdef VMS
+#define EXIT_WARNING  1		/* VMS is very nonstandard */
+#else
+#define EXIT_WARNING  2
+#endif
+#endif

rtgui/common/jpeg/change.log

+CHANGE LOG for Independent JPEG Group's JPEG software
+
+
+Version 7  27-Jun-2009
+----------------------
+
+New scaled DCTs implemented.
+djpeg now supports scalings N/8 with all N from 1 to 16.
+cjpeg now supports scalings 8/N with all N from 1 to 16.
+Scaled DCTs with size larger than 8 are now also used for resolving the
+common 2x2 chroma subsampling case without additional spatial resampling.
+Separate spatial resampling for those kind of files is now only necessary
+for N>8 scaling cases.
+Furthermore, separate scaled DCT functions are provided for direct resolving
+of the common asymmetric subsampling cases (2x1 and 1x2) without additional
+spatial resampling.
+
+cjpeg -quality option has been extended for support of separate quality
+settings for luminance and chrominance (or in general, for every provided
+quantization table slot).
+New API function jpeg_default_qtables() and q_scale_factor array in library.
+
+Added -nosmooth option to cjpeg, complementary to djpeg.
+New variable "do_fancy_downsampling" in library, complement to fancy
+upsampling.  Fancy upsampling now uses direct DCT scaling with sizes
+larger than 8.  The old method is not reversible and has been removed.
+
+Support arithmetic entropy encoding and decoding.
+Added files jaricom.c, jcarith.c, jdarith.c.
+
+Straighten the file structure:
+Removed files jidctred.c, jcphuff.c, jchuff.h, jdphuff.c, jdhuff.h.
+
+jpegtran has a new "lossless" cropping feature.
+
+Implement -perfect option in jpegtran, new API function
+jtransform_perfect_transform() in transupp. (DP 204_perfect.dpatch)
+
+Better error messages for jpegtran fopen failure.
+(DP 203_jpegtran_errmsg.dpatch)
+
+Fix byte order issue with 16bit PPM/PGM files in rdppm.c/wrppm.c:
+according to Netpbm, the de facto standard implementation of the PNM formats,
+the most significant byte is first. (DP 203_rdppm.dpatch)
+
+Add -raw option to rdjpgcom not to mangle the output.
+(DP 205_rdjpgcom_raw.dpatch)
+
+Make rdjpgcom locale aware. (DP 201_rdjpgcom_locale.dpatch)
+
+Add extern "C" to jpeglib.h.
+This avoids the need to put extern "C" { ... } around #include "jpeglib.h"
+in your C++ application.  Defining the symbol DONT_USE_EXTERN_C in the
+configuration prevents this. (DP 202_jpeglib.h_c++.dpatch)
+
+
+Version 6b  27-Mar-1998
+-----------------------
+
+jpegtran has new features for lossless image transformations (rotation
+and flipping) as well as "lossless" reduction to grayscale.
+
+jpegtran now copies comments by default; it has a -copy switch to enable
+copying all APPn blocks as well, or to suppress comments.  (Formerly it
+always suppressed comments and APPn blocks.)  jpegtran now also preserves
+JFIF version and resolution information.
+
+New decompressor library feature: COM and APPn markers found in the input
+file can be saved in memory for later use by the application.  (Before,
+you had to code this up yourself with a custom marker processor.)
+
+There is an unused field "void * client_data" now in compress and decompress
+parameter structs; this may be useful in some applications.
+
+JFIF version number information is now saved by the decoder and accepted by
+the encoder.  jpegtran uses this to copy the source file's version number,
+to ensure "jpegtran -copy all" won't create bogus files that contain JFXX
+extensions but claim to be version 1.01.  Applications that generate their
+own JFXX extension markers also (finally) have a supported way to cause the
+encoder to emit JFIF version number 1.02.
+
+djpeg's trace mode reports JFIF 1.02 thumbnail images as such, rather
+than as unknown APP0 markers.
+
+In -verbose mode, djpeg and rdjpgcom will try to print the contents of
+APP12 markers as text.  Some digital cameras store useful text information
+in APP12 markers.
+
+Handling of truncated data streams is more robust: blocks beyond the one in
+which the error occurs will be output as uniform gray, or left unchanged
+if decoding a progressive JPEG.  The appearance no longer depends on the
+Huffman tables being used.
+
+Huffman tables are checked for validity much more carefully than before.
+
+To avoid the Unisys LZW patent, djpeg's GIF output capability has been
+changed to produce "uncompressed GIFs", and cjpeg's GIF input capability
+has been removed altogether.  We're not happy about it either, but there
+seems to be no good alternative.
+
+The configure script now supports building libjpeg as a shared library
+on many flavors of Unix (all the ones that GNU libtool knows how to
+build shared libraries for).  Use "./configure --enable-shared" to
+try this out.
+
+New jconfig file and makefiles for Microsoft Visual C++ and Developer Studio.
+Also, a jconfig file and a build script for Metrowerks CodeWarrior
+on Apple Macintosh.  makefile.dj has been updated for DJGPP v2, and there
+are miscellaneous other minor improvements in the makefiles.
+
+jmemmac.c now knows how to create temporary files following Mac System 7
+conventions.
+
+djpeg's -map switch is now able to read raw-format PPM files reliably.
+
+cjpeg -progressive -restart no longer generates any unnecessary DRI markers.
+
+Multiple calls to jpeg_simple_progression for a single JPEG object
+no longer leak memory.
+
+
+Version 6a  7-Feb-96
+--------------------
+
+Library initialization sequence modified to detect version mismatches
+and struct field packing mismatches between library and calling application.
+This change requires applications to be recompiled, but does not require
+any application source code change.
+
+All routine declarations changed to the style "GLOBAL(type) name ...",
+that is, GLOBAL, LOCAL, METHODDEF, EXTERN are now macros taking the
+routine's return type as an argument.  This makes it possible to add
+Microsoft-style linkage keywords to all the routines by changing just
+these macros.  Note that any application code that was using these macros
+will have to be changed.
+
+DCT coefficient quantization tables are now stored in normal array order
+rather than zigzag order.  Application code that calls jpeg_add_quant_table,
+or otherwise manipulates quantization tables directly, will need to be
+changed.  If you need to make such code work with either older or newer
+versions of the library, a test like "#if JPEG_LIB_VERSION >= 61" is
+recommended.
+
+djpeg's trace capability now dumps DQT tables in natural order, not zigzag
+order.  This allows the trace output to be made into a "-qtables" file
+more easily.
+
+New system-dependent memory manager module for use on Apple Macintosh.
+
+Fix bug in cjpeg's -smooth option: last one or two scanlines would be
+duplicates of the prior line unless the image height mod 16 was 1 or 2.
+
+Repair minor problems in VMS, BCC, MC6 makefiles.
+
+New configure script based on latest GNU Autoconf.
+
+Correct the list of include files needed by MetroWerks C for ccommand().
+
+Numerous small documentation updates.
+
+
+Version 6  2-Aug-95
+-------------------
+
+Progressive JPEG support: library can read and write full progressive JPEG
+files.  A "buffered image" mode supports incremental decoding for on-the-fly
+display of progressive images.  Simply recompiling an existing IJG-v5-based
+decoder with v6 should allow it to read progressive files, though of course
+without any special progressive display.
+
+New "jpegtran" application performs lossless transcoding between different
+JPEG formats; primarily, it can be used to convert baseline to progressive
+JPEG and vice versa.  In support of jpegtran, the library now allows lossless
+reading and writing of JPEG files as DCT coefficient arrays.  This ability
+may be of use in other applications.
+
+Notes for programmers:
+* We changed jpeg_start_decompress() to be able to suspend; this makes all
+decoding modes available to suspending-input applications.  However,
+existing applications that use suspending input will need to be changed
+to check the return value from jpeg_start_decompress().  You don't need to
+do anything if you don't use a suspending data source.
+* We changed the interface to the virtual array routines: access_virt_array
+routines now take a count of the number of rows to access this time.  The
+last parameter to request_virt_array routines is now interpreted as the
+maximum number of rows that may be accessed at once, but not necessarily
+the height of every access.
+
+
+Version 5b  15-Mar-95
+---------------------
+
+Correct bugs with grayscale images having v_samp_factor > 1.
+
+jpeg_write_raw_data() now supports output suspension.
+
+Correct bugs in "configure" script for case of compiling in
+a directory other than the one containing the source files.
+
+Repair bug in jquant1.c: sometimes didn't use as many colors as it could.
+
+Borland C makefile and jconfig file work under either MS-DOS or OS/2.
+
+Miscellaneous improvements to documentation.
+
+
+Version 5a  7-Dec-94
+--------------------
+
+Changed color conversion roundoff behavior so that grayscale values are
+represented exactly.  (This causes test image files to change.)
+
+Make ordered dither use 16x16 instead of 4x4 pattern for a small quality
+improvement.
+
+New configure script based on latest GNU Autoconf.
+Fix configure script to handle CFLAGS correctly.
+Rename *.auto files to *.cfg, so that configure script still works if
+file names have been truncated for DOS.
+
+Fix bug in rdbmp.c: didn't allow for extra data between header and image.
+
+Modify rdppm.c/wrppm.c to handle 2-byte raw PPM/PGM formats for 12-bit data.
+
+Fix several bugs in rdrle.c.
+
+NEED_SHORT_EXTERNAL_NAMES option was broken.
+
+Revise jerror.h/jerror.c for more flexibility in message table.
+
+Repair oversight in jmemname.c NO_MKTEMP case: file could be there
+but unreadable.
+
+
+Version 5  24-Sep-94
+--------------------
+
+Version 5 represents a nearly complete redesign and rewrite of the IJG
+software.  Major user-visible changes include:
+  * Automatic configuration simplifies installation for most Unix systems.
+  * A range of speed vs. image quality tradeoffs are supported.
+    This includes resizing of an image during decompression: scaling down
+    by a factor of 1/2, 1/4, or 1/8 is handled very efficiently.
+  * New programs rdjpgcom and wrjpgcom allow insertion and extraction
+    of text comments in a JPEG file.
+
+The application programmer's interface to the library has changed completely.
+Notable improvements include:
+  * We have eliminated the use of callback routines for handling the
+    uncompressed image data.  The application now sees the library as a
+    set of routines that it calls to read or write image data on a
+    scanline-by-scanline basis.
+  * The application image data is represented in a conventional interleaved-
+    pixel format, rather than as a separate array for each color channel.
+    This can save a copying step in many programs.
+  * The handling of compressed data has been cleaned up: the application can
+    supply routines to source or sink the compressed data.  It is possible to
+    suspend processing on source/sink buffer overrun, although this is not
+    supported in all operating modes.
+  * All static state has been eliminated from the library, so that multiple
+    instances of compression or decompression can be active concurrently.
+  * JPEG abbreviated datastream formats are supported, ie, quantization and
+    Huffman tables can be stored separately from the image data.
+  * And not only that, but the documentation of the library has improved
+    considerably!
+
+
+The last widely used release before the version 5 rewrite was version 4A of
+18-Feb-93.  Change logs before that point have been discarded, since they
+are not of much interest after the rewrite.

rtgui/common/jpeg/cjpeg.1

+.TH CJPEG 1 "10 June 2009"
+.SH NAME
+cjpeg \- compress an image file to a JPEG file
+.SH SYNOPSIS
+.B cjpeg
+[
+.I options
+]
+[
+.I filename
+]
+.LP
+.SH DESCRIPTION
+.LP
+.B cjpeg
+compresses the named image file, or the standard input if no file is
+named, and produces a JPEG/JFIF file on the standard output.
+The currently supported input file formats are: PPM (PBMPLUS color
+format), PGM (PBMPLUS gray-scale format), BMP, Targa, and RLE (Utah Raster
+Toolkit format).  (RLE is supported only if the URT library is available.)
+.SH OPTIONS
+All switch names may be abbreviated; for example,
+.B \-grayscale
+may be written
+.B \-gray
+or
+.BR \-gr .
+Most of the "basic" switches can be abbreviated to as little as one letter.
+Upper and lower case are equivalent (thus
+.B \-BMP
+is the same as
+.BR \-bmp ).
+British spellings are also accepted (e.g.,
+.BR \-greyscale ),
+though for brevity these are not mentioned below.
+.PP
+The basic switches are:
+.TP
+.BI \-quality " N[,...]"
+Scale quantization tables to adjust image quality.  Quality is 0 (worst) to
+100 (best); default is 75.  (See below for more info.)
+.TP
+.B \-grayscale
+Create monochrome JPEG file from color input.  Be sure to use this switch when
+compressing a grayscale BMP file, because
+.B cjpeg
+isn't bright enough to notice whether a BMP file uses only shades of gray.
+By saying
+.BR \-grayscale ,
+you'll get a smaller JPEG file that takes less time to process.
+.TP
+.B \-optimize
+Perform optimization of entropy encoding parameters.  Without this, default
+encoding parameters are used.
+.B \-optimize
+usually makes the JPEG file a little smaller, but
+.B cjpeg
+runs somewhat slower and needs much more memory.  Image quality and speed of
+decompression are unaffected by
+.BR \-optimize .
+.TP
+.B \-progressive
+Create progressive JPEG file (see below).
+.TP
+.BI \-scale " M/N"
+Scale the output image by a factor M/N.  Currently supported scale factors are
+8/N with all N from 1 to 16.
+.TP
+.B \-targa
+Input file is Targa format.  Targa files that contain an "identification"
+field will not be automatically recognized by
+.BR cjpeg ;
+for such files you must specify
+.B \-targa
+to make
+.B cjpeg
+treat the input as Targa format.
+For most Targa files, you won't need this switch.
+.PP
+The
+.B \-quality
+switch lets you trade off compressed file size against quality of the
+reconstructed image: the higher the quality setting, the larger the JPEG file,
+and the closer the output image will be to the original input.  Normally you
+want to use the lowest quality setting (smallest file) that decompresses into
+something visually indistinguishable from the original image.  For this
+purpose the quality setting should be between 50 and 95; the default of 75 is
+often about right.  If you see defects at
+.B \-quality
+75, then go up 5 or 10 counts at a time until you are happy with the output
+image.  (The optimal setting will vary from one image to another.)
+.PP
+.B \-quality
+100 will generate a quantization table of all 1's, minimizing loss in the
+quantization step (but there is still information loss in subsampling, as well
+as roundoff error).  This setting is mainly of interest for experimental
+purposes.  Quality values above about 95 are
+.B not
+recommended for normal use; the compressed file size goes up dramatically for
+hardly any gain in output image quality.
+.PP
+In the other direction, quality values below 50 will produce very small files
+of low image quality.  Settings around 5 to 10 might be useful in preparing an
+index of a large image library, for example.  Try
+.B \-quality
+2 (or so) for some amusing Cubist effects.  (Note: quality
+values below about 25 generate 2-byte quantization tables, which are
+considered optional in the JPEG standard.
+.B cjpeg
+emits a warning message when you give such a quality value, because some
+other JPEG programs may be unable to decode the resulting file.  Use
+.B \-baseline
+if you need to ensure compatibility at low quality values.)
+.PP
+The
+.B \-quality
+option has been extended in IJG version 7 for support of separate quality
+settings for luminance and chrominance (or in general, for every provided
+quantization table slot).  This feature is useful for high-quality
+applications which cannot accept the damage of color data by coarse
+subsampling settings.  You can now easily reduce the color data amount more
+smoothly with finer control without separate subsampling.  The resulting file
+is fully compliant with standard JPEG decoders.
+Note that the
+.B \-quality
+ratings refer to the quantization table slots, and that the last value is
+replicated if there are more q-table slots than parameters.  The default
+q-table slots are 0 for luminance and 1 for chrominance with default tables as
+given in the JPEG standard.  This is compatible with the old behaviour in case
+that only one parameter is given, which is then used for both luminance and
+chrominance (slots 0 and 1).  More or custom quantization tables can be set
+with
+.B \-qtables
+and assigned to components with
+.B \-qslots
+parameter (see the "wizard" switches below).
+.B Caution:
+You must explicitely add
+.BI \-sample " 1x1"
+for efficient separate color
+quality selection, since the default value used by library is 2x2!
+.PP
+The
+.B \-progressive
+switch creates a "progressive JPEG" file.  In this type of JPEG file, the data
+is stored in multiple scans of increasing quality.  If the file is being
+transmitted over a slow communications link, the decoder can use the first
+scan to display a low-quality image very quickly, and can then improve the
+display with each subsequent scan.  The final image is exactly equivalent to a
+standard JPEG file of the same quality setting, and the total file size is
+about the same --- often a little smaller.
+.PP
+Switches for advanced users:
+.TP
+.B \-dct int
+Use integer DCT method (default).
+.TP
+.B \-dct fast
+Use fast integer DCT (less accurate).
+.TP
+.B \-dct float
+Use floating-point DCT method.
+The float method is very slightly more accurate than the int method, but is
+much slower unless your machine has very fast floating-point hardware.  Also
+note that results of the floating-point method may vary slightly across
+machines, while the integer methods should give the same results everywhere.
+The fast integer method is much less accurate than the other two.
+.TP
+.B \-nosmooth
+Don't use high-quality downsampling.
+.TP
+.BI \-restart " N"
+Emit a JPEG restart marker every N MCU rows, or every N MCU blocks if "B" is
+attached to the number.
+.B \-restart 0
+(the default) means no restart markers.
+.TP
+.BI \-smooth " N"
+Smooth the input image to eliminate dithering noise.  N, ranging from 1 to
+100, indicates the strength of smoothing.  0 (the default) means no smoothing.
+.TP
+.BI \-maxmemory " N"
+Set limit for amount of memory to use in processing large images.  Value is
+in thousands of bytes, or millions of bytes if "M" is attached to the
+number.  For example,
+.B \-max 4m
+selects 4000000 bytes.  If more space is needed, temporary files will be used.
+.TP
+.BI \-outfile " name"
+Send output image to the named file, not to standard output.
+.TP
+.B \-verbose
+Enable debug printout.  More
+.BR \-v 's
+give more output.  Also, version information is printed at startup.
+.TP
+.B \-debug
+Same as
+.BR \-verbose .
+.PP
+The
+.B \-restart
+option inserts extra markers that allow a JPEG decoder to resynchronize after
+a transmission error.  Without restart markers, any damage to a compressed
+file will usually ruin the image from the point of the error to the end of the
+image; with restart markers, the damage is usually confined to the portion of
+the image up to the next restart marker.  Of course, the restart markers
+occupy extra space.  We recommend
+.B \-restart 1
+for images that will be transmitted across unreliable networks such as Usenet.
+.PP
+The
+.B \-smooth
+option filters the input to eliminate fine-scale noise.  This is often useful
+when converting dithered images to JPEG: a moderate smoothing factor of 10 to
+50 gets rid of dithering patterns in the input file, resulting in a smaller
+JPEG file and a better-looking image.  Too large a smoothing factor will
+visibly blur the image, however.
+.PP
+Switches for wizards:
+.TP
+.B \-arithmetic
+Use arithmetic coding.
+.B Caution:
+arithmetic coded JPEG is not yet widely implemented, so many decoders will be
+unable to view an arithmetic coded JPEG file at all.
+.TP
+.B \-baseline
+Force baseline-compatible quantization tables to be generated.  This clamps
+quantization values to 8 bits even at low quality settings.  (This switch is
+poorly named, since it does not ensure that the output is actually baseline
+JPEG.  For example, you can use
+.B \-baseline
+and
+.B \-progressive
+together.)
+.TP
+.BI \-qtables " file"
+Use the quantization tables given in the specified text file.
+.TP
+.BI \-qslots " N[,...]"
+Select which quantization table to use for each color component.
+.TP
+.BI \-sample " HxV[,...]"
+Set JPEG sampling factors for each color component.
+.TP
+.BI \-scans " file"
+Use the scan script given in the specified text file.
+.PP
+The "wizard" switches are intended for experimentation with JPEG.  If you
+don't know what you are doing, \fBdon't use them\fR.  These switches are
+documented further in the file wizard.txt.
+.SH EXAMPLES
+.LP
+This example compresses the PPM file foo.ppm with a quality factor of
+60 and saves the output as foo.jpg:
+.IP
+.B cjpeg \-quality
+.I 60 foo.ppm
+.B >
+.I foo.jpg
+.SH HINTS
+Color GIF files are not the ideal input for JPEG; JPEG is really intended for
+compressing full-color (24-bit) images.  In particular, don't try to convert
+cartoons, line drawings, and other images that have only a few distinct
+colors.  GIF works great on these, JPEG does not.  If you want to convert a
+GIF to JPEG, you should experiment with
+.BR cjpeg 's
+.B \-quality
+and
+.B \-smooth
+options to get a satisfactory conversion.
+.B \-smooth 10
+or so is often helpful.
+.PP
+Avoid running an image through a series of JPEG compression/decompression
+cycles.  Image quality loss will accumulate; after ten or so cycles the image
+may be noticeably worse than it was after one cycle.  It's best to use a
+lossless format while manipulating an image, then convert to JPEG format when
+you are ready to file the image away.
+.PP
+The
+.B \-optimize
+option to
+.B cjpeg
+is worth using when you are making a "final" version for posting or archiving.
+It's also a win when you are using low quality settings to make very small
+JPEG files; the percentage improvement is often a lot more than it is on
+larger files.  (At present,
+.B \-optimize
+mode is always selected when generating progressive JPEG files.)
+.SH ENVIRONMENT
+.TP
+.B JPEGMEM
+If this environment variable is set, its value is the default memory limit.
+The value is specified as described for the
+.B \-maxmemory
+switch.
+.B JPEGMEM
+overrides the default value specified when the program was compiled, and
+itself is overridden by an explicit
+.BR \-maxmemory .
+.SH SEE ALSO
+.BR djpeg (1),
+.BR jpegtran (1),
+.BR rdjpgcom (1),
+.BR wrjpgcom (1)
+.br
+.BR ppm (5),
+.BR pgm (5)
+.br
+Wallace, Gregory K.  "The JPEG Still Picture Compression Standard",
+Communications of the ACM, April 1991 (vol. 34, no. 4), pp. 30-44.
+.SH AUTHOR
+Independent JPEG Group
+.SH BUGS
+GIF input files are no longer supported, to avoid the Unisys LZW patent.
+(Conversion of GIF files to JPEG is usually a bad idea anyway.)
+.PP
+Not all variants of BMP and Targa file formats are supported.
+.PP
+The
+.B \-targa
+switch is not a bug, it's a feature.  (It would be a bug if the Targa format
+designers had not been clueless.)
\ No newline at end of file

rtgui/common/jpeg/ckconfig.c

+/*
+ * ckconfig.c
+ *
+ * Copyright (C) 1991-1994, Thomas G. Lane.
+ * This file is part of the Independent JPEG Group's software.
+ * For conditions of distribution and use, see the accompanying README file.
+ */
+
+/*
+ * This program is intended to help you determine how to configure the JPEG
+ * software for installation on a particular system.  The idea is to try to
+ * compile and execute this program.  If your compiler fails to compile the
+ * program, make changes as indicated in the comments below.  Once you can
+ * compile the program, run it, and it will produce a "jconfig.h" file for
+ * your system.
+ *
+ * As a general rule, each time you try to compile this program,
+ * pay attention only to the *first* error message you get from the compiler.
+ * Many C compilers will issue lots of spurious error messages once they
+ * have gotten confused.  Go to the line indicated in the first error message,
+ * and read the comments preceding that line to see what to change.
+ *
+ * Almost all of the edits you may need to make to this program consist of
+ * changing a line that reads "#define SOME_SYMBOL" to "#undef SOME_SYMBOL",
+ * or vice versa.  This is called defining or undefining that symbol.
+ */
+
+
+/* First we must see if your system has the include files we need.
+ * We start out with the assumption that your system has all the ANSI-standard
+ * include files.  If you get any error trying to include one of these files,
+ * undefine the corresponding HAVE_xxx symbol.
+ */
+
+#define HAVE_STDDEF_H		/* replace 'define' by 'undef' if error here */
+#ifdef HAVE_STDDEF_H		/* next line will be skipped if you undef... */
+#include <stddef.h>
+#endif
+
+#define HAVE_STDLIB_H		/* same thing for stdlib.h */
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+
+#include <stdio.h>		/* If you ain't got this, you ain't got C. */
+
+/* We have to see if your string functions are defined by
+ * strings.h (old BSD convention) or string.h (everybody else).
+ * We try the non-BSD convention first; define NEED_BSD_STRINGS
+ * if the compiler says it can't find string.h.
+ */
+
+#undef NEED_BSD_STRINGS
+
+#ifdef NEED_BSD_STRINGS
+#include <strings.h>
+#else
+#include <string.h>
+#endif
+
+/* On some systems (especially older Unix machines), type size_t is
+ * defined only in the include file <sys/types.h>.  If you get a failure
+ * on the size_t test below, try defining NEED_SYS_TYPES_H.
+ */
+
+#undef NEED_SYS_TYPES_H		/* start by assuming we don't need it */
+#ifdef NEED_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+
+
+/* Usually type size_t is defined in one of the include files we've included
+ * above.  If not, you'll get an error on the "typedef size_t my_size_t;" line.
+ * In that case, first try defining NEED_SYS_TYPES_H just above.
+ * If that doesn't work, you'll have to search through your system library
+ * to figure out which include file defines "size_t".  Look for a line that
+ * says "typedef something-or-other size_t;".  Then, change the line below
+ * that says "#include <someincludefile.h>" to instead include the file
+ * you found size_t in, and define NEED_SPECIAL_INCLUDE.  If you can't find
+ * type size_t anywhere, try replacing "#include <someincludefile.h>" with
+ * "typedef unsigned int size_t;".
+ */
+
+#undef NEED_SPECIAL_INCLUDE	/* assume we DON'T need it, for starters */
+
+#ifdef NEED_SPECIAL_INCLUDE
+#include <someincludefile.h>
+#endif
+
+typedef size_t my_size_t;	/* The payoff: do we have size_t now? */
+
+
+/* The next question is whether your compiler supports ANSI-style function
+ * prototypes.  You need to know this in order to choose between using
+ * makefile.ansi and using makefile.unix.
+ * The #define line below is set to assume you have ANSI function prototypes.
+ * If you get an error in this group of lines, undefine HAVE_PROTOTYPES.
+ */
+
+#define HAVE_PROTOTYPES
+
+#ifdef HAVE_PROTOTYPES
+int testfunction (int arg1, int * arg2); /* check prototypes */
+
+struct methods_struct {		/* check method-pointer declarations */
+  int (*error_exit) (char *msgtext);
+  int (*trace_message) (char *msgtext);
+  int (*another_method) (void);
+};
+
+int testfunction (int arg1, int * arg2) /* check definitions */
+{
+  return arg2[arg1];
+}
+
+int test2function (void)	/* check void arg list */
+{
+  return 0;
+}
+#endif
+
+
+/* Now we want to find out if your compiler knows what "unsigned char" means.
+ * If you get an error on the "unsigned char un_char;" line,
+ * then undefine HAVE_UNSIGNED_CHAR.
+ */
+
+#define HAVE_UNSIGNED_CHAR
+
+#ifdef HAVE_UNSIGNED_CHAR
+unsigned char un_char;
+#endif
+
+
+/* Now we want to find out if your compiler knows what "unsigned short" means.
+ * If you get an error on the "unsigned short un_short;" line,
+ * then undefine HAVE_UNSIGNED_SHORT.
+ */
+
+#define HAVE_UNSIGNED_SHORT
+
+#ifdef HAVE_UNSIGNED_SHORT
+unsigned short un_short;
+#endif
+
+
+/* Now we want to find out if your compiler understands type "void".
+ * If you get an error anywhere in here, undefine HAVE_VOID.
+ */
+
+#define HAVE_VOID
+
+#ifdef HAVE_VOID
+/* Caution: a C++ compiler will insist on complete prototypes */
+typedef void * void_ptr;	/* check void * */
+#ifdef HAVE_PROTOTYPES		/* check ptr to function returning void */
+typedef void (*void_func) (int a, int b);
+#else
+typedef void (*void_func) ();
+#endif
+
+#ifdef HAVE_PROTOTYPES		/* check void function result */
+void test3function (void_ptr arg1, void_func arg2)
+#else
+void test3function (arg1, arg2)
+     void_ptr arg1;
+     void_func arg2;
+#endif
+{
+  char * locptr = (char *) arg1; /* check casting to and from void * */
+  arg1 = (void *) locptr;
+  (*arg2) (1, 2);		/* check call of fcn returning void */
+}
+#endif
+
+
+/* Now we want to find out if your compiler knows what "const" means.
+ * If you get an error here, undefine HAVE_CONST.
+ */
+
+#define HAVE_CONST
+
+#ifdef HAVE_CONST
+static const int carray[3] = {1, 2, 3};
+
+#ifdef HAVE_PROTOTYPES
+int test4function (const int arg1)
+#else
+int test4function (arg1)
+     const int arg1;
+#endif
+{
+  return carray[arg1];
+}
+#endif
+
+
+/* If you get an error or warning about this structure definition,
+ * define INCOMPLETE_TYPES_BROKEN.
+ */
+
+#undef INCOMPLETE_TYPES_BROKEN
+
+#ifndef INCOMPLETE_TYPES_BROKEN
+typedef struct undefined_structure * undef_struct_ptr;
+#endif
+
+
+/* If you get an error about duplicate names,
+ * define NEED_SHORT_EXTERNAL_NAMES.
+ */
+
+#undef NEED_SHORT_EXTERNAL_NAMES
+
+#ifndef NEED_SHORT_EXTERNAL_NAMES
+
+int possibly_duplicate_function ()
+{
+  return 0;
+}
+
+int possibly_dupli_function ()
+{
+  return 1;
+}
+
+#endif
+
+
+
+/************************************************************************
+ *  OK, that's it.  You should not have to change anything beyond this
+ *  point in order to compile and execute this program.  (You might get
+ *  some warnings, but you can ignore them.)
+ *  When you run the program, it will make a couple more tests that it
+ *  can do automatically, and then it will create jconfig.h and print out
+ *  any additional suggestions it has.
+ ************************************************************************
+ */
+
+
+#ifdef HAVE_PROTOTYPES
+int is_char_signed (int arg)
+#else
+int is_char_signed (arg)
+     int arg;
+#endif
+{
+  if (arg == 189) {		/* expected result for unsigned char */
+    return 0;			/* type char is unsigned */
+  }
+  else if (arg != -67) {	/* expected result for signed char */
+    printf("Hmm, it seems 'char' is not eight bits wide on your machine.\n");
+    printf("I fear the JPEG software will not work at all.\n\n");
+  }
+  return 1;			/* assume char is signed otherwise */
+}
+
+
+#ifdef HAVE_PROTOTYPES
+int is_shifting_signed (long arg)
+#else
+int is_shifting_signed (arg)
+     long arg;
+#endif
+/* See whether right-shift on a long is signed or not. */
+{
+  long res = arg >> 4;
+
+  if (res == -0x7F7E80CL) {	/* expected result for signed shift */
+    return 1;			/* right shift is signed */
+  }
+  /* see if unsigned-shift hack will fix it. */
+  /* we can't just test exact value since it depends on width of long... */
+  res |= (~0L) << (32-4);
+  if (res == -0x7F7E80CL) {	/* expected result now? */
+    return 0;			/* right shift is unsigned */
+  }
+  printf("Right shift isn't acting as I expect it to.\n");
+  printf("I fear the JPEG software will not work at all.\n\n");
+  return 0;			/* try it with unsigned anyway */
+}
+
+
+#ifdef HAVE_PROTOTYPES
+int main (int argc, char ** argv)
+#else
+int main (argc, argv)
+     int argc;
+     char ** argv;
+#endif
+{
+  char signed_char_check = (char) (-67);
+  FILE *outfile;
+
+  /* Attempt to write jconfig.h */
+  if ((outfile = fopen("jconfig.h", "w")) == NULL) {
+    printf("Failed to write jconfig.h\n");
+    return 1;
+  }
+
+  /* Write out all the info */
+  fprintf(outfile, "/* jconfig.h --- generated by ckconfig.c */\n");
+  fprintf(outfile, "/* see jconfig.txt for explanations */\n\n");
+#ifdef HAVE_PROTOTYPES
+  fprintf(outfile, "#define HAVE_PROTOTYPES\n");
+#else
+  fprintf(outfile, "#undef HAVE_PROTOTYPES\n");
+#endif
+#ifdef HAVE_UNSIGNED_CHAR
+  fprintf(outfile, "#define HAVE_UNSIGNED_CHAR\n");
+#else
+  fprintf(outfile, "#undef HAVE_UNSIGNED_CHAR\n");
+#endif
+#ifdef HAVE_UNSIGNED_SHORT
+  fprintf(outfile, "#define HAVE_UNSIGNED_SHORT\n");
+#else
+  fprintf(outfile, "#undef HAVE_UNSIGNED_SHORT\n");
+#endif
+#ifdef HAVE_VOID
+  fprintf(outfile, "/* #define void char */\n");
+#else
+  fprintf(outfile, "#define void char\n");
+#endif
+#ifdef HAVE_CONST
+  fprintf(outfile, "/* #define const */\n");
+#else
+  fprintf(outfile, "#define const\n");
+#endif
+  if (is_char_signed((int) signed_char_check))
+    fprintf(outfile, "#undef CHAR_IS_UNSIGNED\n");
+  else
+    fprintf(outfile, "#define CHAR_IS_UNSIGNED\n");
+#ifdef HAVE_STDDEF_H
+  fprintf(outfile, "#define HAVE_STDDEF_H\n");
+#else
+  fprintf(outfile, "#undef HAVE_STDDEF_H\n");
+#endif
+#ifdef HAVE_STDLIB_H
+  fprintf(outfile, "#define HAVE_STDLIB_H\n");
+#else
+  fprintf(outfile, "#undef HAVE_STDLIB_H\n");
+#endif
+#ifdef NEED_BSD_STRINGS
+  fprintf(outfile, "#define NEED_BSD_STRINGS\n");
+#else
+  fprintf(outfile, "#undef NEED_BSD_STRINGS\n");
+#endif
+#ifdef NEED_SYS_TYPES_H
+  fprintf(outfile, "#define NEED_SYS_TYPES_H\n");
+#else
+  fprintf(outfile, "#undef NEED_SYS_TYPES_H\n");
+#endif
+  fprintf(outfile, "#undef NEED_FAR_POINTERS\n");
+#ifdef NEED_SHORT_EXTERNAL_NAMES
+  fprintf(outfile, "#define NEED_SHORT_EXTERNAL_NAMES\n");
+#else
+  fprintf(outfile, "#undef NEED_SHORT_EXTERNAL_NAMES\n");
+#endif
+#ifdef INCOMPLETE_TYPES_BROKEN
+  fprintf(outfile, "#define INCOMPLETE_TYPES_BROKEN\n");
+#else
+  fprintf(outfile, "#undef INCOMPLETE_TYPES_BROKEN\n");
+#endif
+  fprintf(outfile, "\n#ifdef JPEG_INTERNALS\n\n");
+  if (is_shifting_signed(-0x7F7E80B1L))
+    fprintf(outfile, "#undef RIGHT_SHIFT_IS_UNSIGNED\n");
+  else
+    fprintf(outfile, "#define RIGHT_SHIFT_IS_UNSIGNED\n");
+  fprintf(outfile, "\n#endif /* JPEG_INTERNALS */\n");
+  fprintf(outfile, "\n#ifdef JPEG_CJPEG_DJPEG\n\n");
+  fprintf(outfile, "#define BMP_SUPPORTED		/* BMP image file format */\n");
+  fprintf(outfile, "#define GIF_SUPPORTED		/* GIF image file format */\n");
+  fprintf(outfile, "#define PPM_SUPPORTED		/* PBMPLUS PPM/PGM image file format */\n");
+  fprintf(outfile, "#undef RLE_SUPPORTED		/* Utah RLE image file format */\n");
+  fprintf(outfile, "#define TARGA_SUPPORTED		/* Targa image file format */\n\n");
+  fprintf(outfile, "#undef TWO_FILE_COMMANDLINE	/* You may need this on non-Unix systems */\n");
+  fprintf(outfile, "#undef NEED_SIGNAL_CATCHER	/* Define this if you use jmemname.c */\n");
+  fprintf(outfile, "#undef DONT_USE_B_MODE\n");
+  fprintf(outfile, "/* #define PROGRESS_REPORT */	/* optional */\n");
+  fprintf(outfile, "\n#endif /* JPEG_CJPEG_DJPEG */\n");
+
+  /* Close the jconfig.h file */
+  fclose(outfile);
+
+  /* User report */
+  printf("Configuration check for Independent JPEG Group's software done.\n");
+  printf("\nI have written the jconfig.h file for you.\n\n");
+#ifdef HAVE_PROTOTYPES
+  printf("You should use makefile.ansi as the starting point for your Makefile.\n");
+#else
+  printf("You should use makefile.unix as the starting point for your Makefile.\n");
+#endif
+
+#ifdef NEED_SPECIAL_INCLUDE
+  printf("\nYou'll need to change jconfig.h to include the system include file\n");
+  printf("that you found type size_t in, or add a direct definition of type\n");
+  printf("size_t if that's what you used.  Just add it to the end.\n");
+#endif
+
+  return 0;
+}

rtgui/common/jpeg/jcinit.c

+/*
+ * jcinit.c
+ *
+ * Copyright (C) 1991-1997, Thomas G. Lane.
+ * This file is part of the Independent JPEG Group's software.
+ * For conditions of distribution and use, see the accompanying README file.
+ *
+ * This file contains initialization logic for the JPEG compressor.
+ * This routine is in charge of selecting the modules to be executed and
+ * making an initialization call to each one.
+ *
+ * Logically, this code belongs in jcmaster.c.  It's split out because
+ * linking this routine implies linking the entire compression library.
+ * For a transcoding-only application, we want to be able to use jcmaster.c
+ * without linking in the whole library.
+ */
+
+#define JPEG_INTERNALS
+#include "jinclude.h"
+#include "jpeglib.h"
+
+
+/*
+ * Master selection of compression modules.
+ * This is done once at the start of processing an image.  We determine
+ * which modules will be used and give them appropriate initialization calls.
+ */
+
+GLOBAL(void)
+jinit_compress_master (j_compress_ptr cinfo)
+{
+  /* Initialize master control (includes parameter checking/processing) */
+  jinit_c_master_control(cinfo, FALSE /* full compression */);
+
+  /* Preprocessing */
+  if (! cinfo->raw_data_in) {
+    jinit_color_converter(cinfo);
+    jinit_downsampler(cinfo);
+    jinit_c_prep_controller(cinfo, FALSE /* never need full buffer here */);
+  }
+  /* Forward DCT */
+  jinit_forward_dct(cinfo);
+  /* Entropy encoding: either Huffman or arithmetic coding. */
+  if (cinfo->arith_code)
+    jinit_arith_encoder(cinfo);
+  else {
+    jinit_huff_encoder(cinfo);
+  }
+
+  /* Need a full-image coefficient buffer in any multi-pass mode. */
+  jinit_c_coef_controller(cinfo,
+		(boolean) (cinfo->num_scans > 1 || cinfo->optimize_coding));
+  jinit_c_main_controller(cinfo, FALSE /* never need full buffer here */);
+
+  jinit_marker_writer(cinfo);
+
+  /* We can now tell the memory manager to allocate virtual arrays. */
+  (*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo);
+
+  /* Write the datastream header (SOI) immediately.
+   * Frame and scan headers are postponed till later.
+   * This lets application insert special markers after the SOI.
+   */
+  (*cinfo->marker->write_file_header) (cinfo);
+}