提交 d5272d32 编写于 作者: S Sean Barrett

renaming completed through png decoder

上级 7add5044
......@@ -1977,22 +1977,22 @@ static int stbi__jpeg_info(stbi__context *s, int *x, int *y, int *comp)
// - fast huffman
// fast-way is faster to check than jpeg huffman, but slow way is slower
#define ZFAST_BITS 9 // accelerate all cases in default tables
#define ZFAST_MASK ((1 << ZFAST_BITS) - 1)
#define STBI__ZFAST_BITS 9 // accelerate all cases in default tables
#define STBI__ZFAST_MASK ((1 << STBI__ZFAST_BITS) - 1)
// zlib-style huffman encoding
// (jpegs packs from left, zlib from right, so can't share code)
typedef struct
{
stbi__uint16 fast[1 << ZFAST_BITS];
stbi__uint16 fast[1 << STBI__ZFAST_BITS];
stbi__uint16 firstcode[16];
int maxcode[17];
stbi__uint16 firstsymbol[16];
stbi__uint8 size[288];
stbi__uint16 value[288];
} zhuffman;
} stbi__zhuffman;
stbi_inline static int bitreverse16(int n)
stbi_inline static int stbi__bitreverse16(int n)
{
n = ((n & 0xAAAA) >> 1) | ((n & 0x5555) << 1);
n = ((n & 0xCCCC) >> 2) | ((n & 0x3333) << 2);
......@@ -2001,15 +2001,15 @@ stbi_inline static int bitreverse16(int n)
return n;
}
stbi_inline static int bit_reverse(int v, int bits)
stbi_inline static int stbi__bit_reverse(int v, int bits)
{
assert(bits <= 16);
// to bit reverse n bits, reverse 16 and shift
// stbi__err.g. 11 bits, bit reverse and shift away 5
return bitreverse16(v) >> (16-bits);
return stbi__bitreverse16(v) >> (16-bits);
}
static int zbuild_huffman(zhuffman *z, stbi__uint8 *sizelist, int num)
static int stbi__zbuild_huffman(stbi__zhuffman *z, stbi__uint8 *sizelist, int num)
{
int i,k=0;
int code, next_code[16], sizes[17];
......@@ -2041,9 +2041,9 @@ static int zbuild_huffman(zhuffman *z, stbi__uint8 *sizelist, int num)
int c = next_code[s] - z->firstcode[s] + z->firstsymbol[s];
z->size[c] = (stbi__uint8)s;
z->value[c] = (stbi__uint16)i;
if (s <= ZFAST_BITS) {
int k = bit_reverse(next_code[s],s);
while (k < (1 << ZFAST_BITS)) {
if (s <= STBI__ZFAST_BITS) {
int k = stbi__bit_reverse(next_code[s],s);
while (k < (1 << STBI__ZFAST_BITS)) {
z->fast[k] = (stbi__uint16) c;
k += (1 << s);
}
......@@ -2071,39 +2071,39 @@ typedef struct
char *zout_end;
int z_expandable;
zhuffman z_length, z_distance;
} zbuf;
stbi__zhuffman z_length, z_distance;
} stbi__zbuf;
stbi_inline static int zget8(zbuf *z)
stbi_inline static int stbi__zget8(stbi__zbuf *z)
{
if (z->zbuffer >= z->zbuffer_end) return 0;
return *z->zbuffer++;
}
static void fill_bits(zbuf *z)
static void stbi__fill_bits(stbi__zbuf *z)
{
do {
assert(z->code_buffer < (1U << z->num_bits));
z->code_buffer |= zget8(z) << z->num_bits;
z->code_buffer |= stbi__zget8(z) << z->num_bits;
z->num_bits += 8;
} while (z->num_bits <= 24);
}
stbi_inline static unsigned int zreceive(zbuf *z, int n)
stbi_inline static unsigned int stbi__zreceive(stbi__zbuf *z, int n)
{
unsigned int k;
if (z->num_bits < n) fill_bits(z);
if (z->num_bits < n) stbi__fill_bits(z);
k = z->code_buffer & ((1 << n) - 1);
z->code_buffer >>= n;
z->num_bits -= n;
return k;
}
stbi_inline static int zhuffman_decode(zbuf *a, zhuffman *z)
stbi_inline static int stbi__zhuffman_decode(stbi__zbuf *a, stbi__zhuffman *z)
{
int b,s,k;
if (a->num_bits < 16) fill_bits(a);
b = z->fast[a->code_buffer & ZFAST_MASK];
if (a->num_bits < 16) stbi__fill_bits(a);
b = z->fast[a->code_buffer & STBI__ZFAST_MASK];
if (b < 0xffff) {
s = z->size[b];
a->code_buffer >>= s;
......@@ -2113,8 +2113,8 @@ stbi_inline static int zhuffman_decode(zbuf *a, zhuffman *z)
// not resolved by fast table, so compute it the slow way
// use jpeg approach, which requires MSbits at top
k = bit_reverse(a->code_buffer, 16);
for (s=ZFAST_BITS+1; ; ++s)
k = stbi__bit_reverse(a->code_buffer, 16);
for (s=STBI__ZFAST_BITS+1; ; ++s)
if (k < z->maxcode[s])
break;
if (s == 16) return -1; // invalid code!
......@@ -2126,7 +2126,7 @@ stbi_inline static int zhuffman_decode(zbuf *a, zhuffman *z)
return z->value[b];
}
static int expand(zbuf *z, int n) // need to make room for n bytes
static int stbi__zexpand(stbi__zbuf *z, int n) // need to make room for n bytes
{
char *q;
int cur, limit;
......@@ -2143,41 +2143,41 @@ static int expand(zbuf *z, int n) // need to make room for n bytes
return 1;
}
static int length_base[31] = {
static int stbi__zlength_base[31] = {
3,4,5,6,7,8,9,10,11,13,
15,17,19,23,27,31,35,43,51,59,
67,83,99,115,131,163,195,227,258,0,0 };
static int length_extra[31]=
static int stbi__zlength_extra[31]=
{ 0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0,0,0 };
static int dist_base[32] = { 1,2,3,4,5,7,9,13,17,25,33,49,65,97,129,193,
static int stbi__zdist_base[32] = { 1,2,3,4,5,7,9,13,17,25,33,49,65,97,129,193,
257,385,513,769,1025,1537,2049,3073,4097,6145,8193,12289,16385,24577,0,0};
static int dist_extra[32] =
static int stbi__zdist_extra[32] =
{ 0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13};
static int parse_huffman_block(zbuf *a)
static int stbi__parse_huffman_block(stbi__zbuf *a)
{
for(;;) {
int z = zhuffman_decode(a, &a->z_length);
int z = stbi__zhuffman_decode(a, &a->z_length);
if (z < 256) {
if (z < 0) return stbi__err("bad huffman code","Corrupt PNG"); // error in huffman codes
if (a->zout >= a->zout_end) if (!expand(a, 1)) return 0;
if (a->zout >= a->zout_end) if (!stbi__zexpand(a, 1)) return 0;
*a->zout++ = (char) z;
} else {
stbi__uint8 *p;
int len,dist;
if (z == 256) return 1;
z -= 257;
len = length_base[z];
if (length_extra[z]) len += zreceive(a, length_extra[z]);
z = zhuffman_decode(a, &a->z_distance);
len = stbi__zlength_base[z];
if (stbi__zlength_extra[z]) len += stbi__zreceive(a, stbi__zlength_extra[z]);
z = stbi__zhuffman_decode(a, &a->z_distance);
if (z < 0) return stbi__err("bad huffman code","Corrupt PNG");
dist = dist_base[z];
if (dist_extra[z]) dist += zreceive(a, dist_extra[z]);
dist = stbi__zdist_base[z];
if (stbi__zdist_extra[z]) dist += stbi__zreceive(a, stbi__zdist_extra[z]);
if (a->zout - a->zout_start < dist) return stbi__err("bad dist","Corrupt PNG");
if (a->zout + len > a->zout_end) if (!expand(a, len)) return 0;
if (a->zout + len > a->zout_end) if (!stbi__zexpand(a, len)) return 0;
p = (stbi__uint8 *) (a->zout - dist);
while (len--)
*a->zout++ = *p++;
......@@ -2185,58 +2185,58 @@ static int parse_huffman_block(zbuf *a)
}
}
static int compute_huffman_codes(zbuf *a)
static int stbi__compute_huffman_codes(stbi__zbuf *a)
{
static stbi__uint8 length_dezigzag[19] = { 16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15 };
zhuffman z_codelength;
stbi__zhuffman z_codelength;
stbi__uint8 lencodes[286+32+137];//padding for maximum single op
stbi__uint8 codelength_sizes[19];
int i,n;
int hlit = zreceive(a,5) + 257;
int hdist = zreceive(a,5) + 1;
int hclen = zreceive(a,4) + 4;
int hlit = stbi__zreceive(a,5) + 257;
int hdist = stbi__zreceive(a,5) + 1;
int hclen = stbi__zreceive(a,4) + 4;
memset(codelength_sizes, 0, sizeof(codelength_sizes));
for (i=0; i < hclen; ++i) {
int s = zreceive(a,3);
int s = stbi__zreceive(a,3);
codelength_sizes[length_dezigzag[i]] = (stbi__uint8) s;
}
if (!zbuild_huffman(&z_codelength, codelength_sizes, 19)) return 0;
if (!stbi__zbuild_huffman(&z_codelength, codelength_sizes, 19)) return 0;
n = 0;
while (n < hlit + hdist) {
int c = zhuffman_decode(a, &z_codelength);
int c = stbi__zhuffman_decode(a, &z_codelength);
assert(c >= 0 && c < 19);
if (c < 16)
lencodes[n++] = (stbi__uint8) c;
else if (c == 16) {
c = zreceive(a,2)+3;
c = stbi__zreceive(a,2)+3;
memset(lencodes+n, lencodes[n-1], c);
n += c;
} else if (c == 17) {
c = zreceive(a,3)+3;
c = stbi__zreceive(a,3)+3;
memset(lencodes+n, 0, c);
n += c;
} else {
assert(c == 18);
c = zreceive(a,7)+11;
c = stbi__zreceive(a,7)+11;
memset(lencodes+n, 0, c);
n += c;
}
}
if (n != hlit+hdist) return stbi__err("bad codelengths","Corrupt PNG");
if (!zbuild_huffman(&a->z_length, lencodes, hlit)) return 0;
if (!zbuild_huffman(&a->z_distance, lencodes+hlit, hdist)) return 0;
if (!stbi__zbuild_huffman(&a->z_length, lencodes, hlit)) return 0;
if (!stbi__zbuild_huffman(&a->z_distance, lencodes+hlit, hdist)) return 0;
return 1;
}
static int parse_uncompressed_block(zbuf *a)
static int stbi__parse_uncomperssed_block(stbi__zbuf *a)
{
stbi__uint8 header[4];
int len,nlen,k;
if (a->num_bits & 7)
zreceive(a, a->num_bits & 7); // discard
stbi__zreceive(a, a->num_bits & 7); // discard
// drain the bit-packed data into header
k = 0;
while (a->num_bits > 0) {
......@@ -2247,25 +2247,25 @@ static int parse_uncompressed_block(zbuf *a)
assert(a->num_bits == 0);
// now fill header the normal way
while (k < 4)
header[k++] = (stbi__uint8) zget8(a);
header[k++] = (stbi__uint8) stbi__zget8(a);
len = header[1] * 256 + header[0];
nlen = header[3] * 256 + header[2];
if (nlen != (len ^ 0xffff)) return stbi__err("zlib corrupt","Corrupt PNG");
if (a->zbuffer + len > a->zbuffer_end) return stbi__err("read past buffer","Corrupt PNG");
if (a->zout + len > a->zout_end)
if (!expand(a, len)) return 0;
if (!stbi__zexpand(a, len)) return 0;
memcpy(a->zout, a->zbuffer, len);
a->zbuffer += len;
a->zout += len;
return 1;
}
static int parse_zlib_header(zbuf *a)
static int stbi__parse_zlib_header(stbi__zbuf *a)
{
int cmf = zget8(a);
int cmf = stbi__zget8(a);
int cm = cmf & 15;
/* int cinfo = cmf >> 4; */
int flg = zget8(a);
int flg = stbi__zget8(a);
if ((cmf*256+flg) % 31 != 0) return stbi__err("bad zlib header","Corrupt PNG"); // zlib spec
if (flg & 32) return stbi__err("no preset dict","Corrupt PNG"); // preset dictionary not allowed in png
if (cm != 8) return stbi__err("bad compression","Corrupt PNG"); // DEFLATE required for png
......@@ -2274,65 +2274,65 @@ static int parse_zlib_header(zbuf *a)
}
// @TODO: should statically initialize these for optimal thread safety
static stbi__uint8 default_length[288], default_distance[32];
static void init_defaults(void)
static stbi__uint8 stbi__zdefault_length[288], stbi__zdefault_distance[32];
static void stbi__init_zdefaults(void)
{
int i; // use <= to match clearly with spec
for (i=0; i <= 143; ++i) default_length[i] = 8;
for ( ; i <= 255; ++i) default_length[i] = 9;
for ( ; i <= 279; ++i) default_length[i] = 7;
for ( ; i <= 287; ++i) default_length[i] = 8;
for (i=0; i <= 143; ++i) stbi__zdefault_length[i] = 8;
for ( ; i <= 255; ++i) stbi__zdefault_length[i] = 9;
for ( ; i <= 279; ++i) stbi__zdefault_length[i] = 7;
for ( ; i <= 287; ++i) stbi__zdefault_length[i] = 8;
for (i=0; i <= 31; ++i) default_distance[i] = 5;
for (i=0; i <= 31; ++i) stbi__zdefault_distance[i] = 5;
}
static int parse_zlib(zbuf *a, int parse_header)
static int stbi__parse_zlib(stbi__zbuf *a, int parse_header)
{
int final, type;
if (parse_header)
if (!parse_zlib_header(a)) return 0;
if (!stbi__parse_zlib_header(a)) return 0;
a->num_bits = 0;
a->code_buffer = 0;
do {
final = zreceive(a,1);
type = zreceive(a,2);
final = stbi__zreceive(a,1);
type = stbi__zreceive(a,2);
if (type == 0) {
if (!parse_uncompressed_block(a)) return 0;
if (!stbi__parse_uncomperssed_block(a)) return 0;
} else if (type == 3) {
return 0;
} else {
if (type == 1) {
// use fixed code lengths
if (!default_distance[31]) init_defaults();
if (!zbuild_huffman(&a->z_length , default_length , 288)) return 0;
if (!zbuild_huffman(&a->z_distance, default_distance, 32)) return 0;
if (!stbi__zdefault_distance[31]) stbi__init_zdefaults();
if (!stbi__zbuild_huffman(&a->z_length , stbi__zdefault_length , 288)) return 0;
if (!stbi__zbuild_huffman(&a->z_distance, stbi__zdefault_distance, 32)) return 0;
} else {
if (!compute_huffman_codes(a)) return 0;
if (!stbi__compute_huffman_codes(a)) return 0;
}
if (!parse_huffman_block(a)) return 0;
if (!stbi__parse_huffman_block(a)) return 0;
}
} while (!final);
return 1;
}
static int do_zlib(zbuf *a, char *obuf, int olen, int exp, int parse_header)
static int stbi__do_zlib(stbi__zbuf *a, char *obuf, int olen, int exp, int parse_header)
{
a->zout_start = obuf;
a->zout = obuf;
a->zout_end = obuf + olen;
a->z_expandable = exp;
return parse_zlib(a, parse_header);
return stbi__parse_zlib(a, parse_header);
}
STBIDEF char *stbi_zlib_decode_malloc_guesssize(const char *buffer, int len, int initial_size, int *outlen)
{
zbuf a;
stbi__zbuf a;
char *p = (char *) malloc(initial_size);
if (p == NULL) return NULL;
a.zbuffer = (stbi__uint8 *) buffer;
a.zbuffer_end = (stbi__uint8 *) buffer + len;
if (do_zlib(&a, p, initial_size, 1, 1)) {
if (stbi__do_zlib(&a, p, initial_size, 1, 1)) {
if (outlen) *outlen = (int) (a.zout - a.zout_start);
return a.zout_start;
} else {
......@@ -2348,12 +2348,12 @@ STBIDEF char *stbi_zlib_decode_malloc(char const *buffer, int len, int *outlen)
STBIDEF char *stbi_zlib_decode_malloc_guesssize_headerflag(const char *buffer, int len, int initial_size, int *outlen, int parse_header)
{
zbuf a;
stbi__zbuf a;
char *p = (char *) malloc(initial_size);
if (p == NULL) return NULL;
a.zbuffer = (stbi__uint8 *) buffer;
a.zbuffer_end = (stbi__uint8 *) buffer + len;
if (do_zlib(&a, p, initial_size, 1, parse_header)) {
if (stbi__do_zlib(&a, p, initial_size, 1, parse_header)) {
if (outlen) *outlen = (int) (a.zout - a.zout_start);
return a.zout_start;
} else {
......@@ -2364,10 +2364,10 @@ STBIDEF char *stbi_zlib_decode_malloc_guesssize_headerflag(const char *buffer, i
STBIDEF int stbi_zlib_decode_buffer(char *obuffer, int olen, char const *ibuffer, int ilen)
{
zbuf a;
stbi__zbuf a;
a.zbuffer = (stbi__uint8 *) ibuffer;
a.zbuffer_end = (stbi__uint8 *) ibuffer + ilen;
if (do_zlib(&a, obuffer, olen, 0, 1))
if (stbi__do_zlib(&a, obuffer, olen, 0, 1))
return (int) (a.zout - a.zout_start);
else
return -1;
......@@ -2375,12 +2375,12 @@ STBIDEF int stbi_zlib_decode_buffer(char *obuffer, int olen, char const *ibuffer
STBIDEF char *stbi_zlib_decode_noheader_malloc(char const *buffer, int len, int *outlen)
{
zbuf a;
stbi__zbuf a;
char *p = (char *) malloc(16384);
if (p == NULL) return NULL;
a.zbuffer = (stbi__uint8 *) buffer;
a.zbuffer_end = (stbi__uint8 *) buffer+len;
if (do_zlib(&a, p, 16384, 1, 0)) {
if (stbi__do_zlib(&a, p, 16384, 1, 0)) {
if (outlen) *outlen = (int) (a.zout - a.zout_start);
return a.zout_start;
} else {
......@@ -2391,10 +2391,10 @@ STBIDEF char *stbi_zlib_decode_noheader_malloc(char const *buffer, int len, int
STBIDEF int stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen)
{
zbuf a;
stbi__zbuf a;
a.zbuffer = (stbi__uint8 *) ibuffer;
a.zbuffer_end = (stbi__uint8 *) ibuffer + ilen;
if (do_zlib(&a, obuffer, olen, 0, 0))
if (stbi__do_zlib(&a, obuffer, olen, 0, 0))
return (int) (a.zout - a.zout_start);
else
return -1;
......@@ -2415,19 +2415,19 @@ typedef struct
{
stbi__uint32 length;
stbi__uint32 type;
} chunk;
} stbi__pngchunk;
#define PNG_TYPE(a,b,c,d) (((a) << 24) + ((b) << 16) + ((c) << 8) + (d))
static chunk get_chunk_header(stbi__context *s)
static stbi__pngchunk stbi__get_chunk_header(stbi__context *s)
{
chunk c;
stbi__pngchunk c;
c.length = stbi__get32be(s);
c.type = stbi__get32be(s);
return c;
}
static int check_png_header(stbi__context *s)
static int stbi__check_png_header(stbi__context *s)
{
static stbi__uint8 png_sig[8] = { 137,80,78,71,13,10,26,10 };
int i;
......@@ -2440,20 +2440,20 @@ typedef struct
{
stbi__context *s;
stbi__uint8 *idata, *expanded, *out;
} png;
} stbi__png;
enum {
F_none=0, F_sub=1, F_up=2, F_avg=3, F_paeth=4,
F_avg_first, F_paeth_first
STBI__F_none=0, STBI__F_sub=1, STBI__F_up=2, STBI__F_avg=3, STBI__F_paeth=4,
STBI__F_avg_first, STBI__F_paeth_first
};
static stbi__uint8 first_row_filter[5] =
{
F_none, F_sub, F_none, F_avg_first, F_paeth_first
STBI__F_none, STBI__F_sub, STBI__F_none, STBI__F_avg_first, STBI__F_paeth_first
};
static int paeth(int a, int b, int c)
static int stbi__paeth(int a, int b, int c)
{
int p = a + b - c;
int pa = abs(p-a);
......@@ -2465,7 +2465,7 @@ static int paeth(int a, int b, int c)
}
// create the png data from post-deflated data
static int create_png_image_raw(png *a, stbi__uint8 *raw, stbi__uint32 raw_len, int out_n, stbi__uint32 x, stbi__uint32 y)
static int stbi__create_png_image_raw(stbi__png *a, stbi__uint8 *raw, stbi__uint32 raw_len, int out_n, stbi__uint32 x, stbi__uint32 y)
{
stbi__context *s = a->s;
stbi__uint32 i,j,stride = x*out_n;
......@@ -2489,13 +2489,13 @@ static int create_png_image_raw(png *a, stbi__uint8 *raw, stbi__uint32 raw_len,
// handle first pixel explicitly
for (k=0; k < img_n; ++k) {
switch (filter) {
case F_none : cur[k] = raw[k]; break;
case F_sub : cur[k] = raw[k]; break;
case F_up : cur[k] = raw[k] + prior[k]; break;
case F_avg : cur[k] = raw[k] + (prior[k]>>1); break;
case F_paeth : cur[k] = (stbi__uint8) (raw[k] + paeth(0,prior[k],0)); break;
case F_avg_first : cur[k] = raw[k]; break;
case F_paeth_first: cur[k] = raw[k]; break;
case STBI__F_none : cur[k] = raw[k]; break;
case STBI__F_sub : cur[k] = raw[k]; break;
case STBI__F_up : cur[k] = raw[k] + prior[k]; break;
case STBI__F_avg : cur[k] = raw[k] + (prior[k]>>1); break;
case STBI__F_paeth : cur[k] = (stbi__uint8) (raw[k] + stbi__paeth(0,prior[k],0)); break;
case STBI__F_avg_first : cur[k] = raw[k]; break;
case STBI__F_paeth_first: cur[k] = raw[k]; break;
}
}
if (img_n != out_n) cur[img_n] = 255;
......@@ -2509,13 +2509,13 @@ static int create_png_image_raw(png *a, stbi__uint8 *raw, stbi__uint32 raw_len,
for (i=x-1; i >= 1; --i, raw+=img_n,cur+=img_n,prior+=img_n) \
for (k=0; k < img_n; ++k)
switch (filter) {
CASE(F_none) cur[k] = raw[k]; break;
CASE(F_sub) cur[k] = raw[k] + cur[k-img_n]; break;
CASE(F_up) cur[k] = raw[k] + prior[k]; break;
CASE(F_avg) cur[k] = raw[k] + ((prior[k] + cur[k-img_n])>>1); break;
CASE(F_paeth) cur[k] = (stbi__uint8) (raw[k] + paeth(cur[k-img_n],prior[k],prior[k-img_n])); break;
CASE(F_avg_first) cur[k] = raw[k] + (cur[k-img_n] >> 1); break;
CASE(F_paeth_first) cur[k] = (stbi__uint8) (raw[k] + paeth(cur[k-img_n],0,0)); break;
CASE(STBI__F_none) cur[k] = raw[k]; break;
CASE(STBI__F_sub) cur[k] = raw[k] + cur[k-img_n]; break;
CASE(STBI__F_up) cur[k] = raw[k] + prior[k]; break;
CASE(STBI__F_avg) cur[k] = raw[k] + ((prior[k] + cur[k-img_n])>>1); break;
CASE(STBI__F_paeth) cur[k] = (stbi__uint8) (raw[k] + stbi__paeth(cur[k-img_n],prior[k],prior[k-img_n])); break;
CASE(STBI__F_avg_first) cur[k] = raw[k] + (cur[k-img_n] >> 1); break;
CASE(STBI__F_paeth_first) cur[k] = (stbi__uint8) (raw[k] + stbi__paeth(cur[k-img_n],0,0)); break;
}
#undef CASE
} else {
......@@ -2525,13 +2525,13 @@ static int create_png_image_raw(png *a, stbi__uint8 *raw, stbi__uint32 raw_len,
for (i=x-1; i >= 1; --i, cur[img_n]=255,raw+=img_n,cur+=out_n,prior+=out_n) \
for (k=0; k < img_n; ++k)
switch (filter) {
CASE(F_none) cur[k] = raw[k]; break;
CASE(F_sub) cur[k] = raw[k] + cur[k-out_n]; break;
CASE(F_up) cur[k] = raw[k] + prior[k]; break;
CASE(F_avg) cur[k] = raw[k] + ((prior[k] + cur[k-out_n])>>1); break;
CASE(F_paeth) cur[k] = (stbi__uint8) (raw[k] + paeth(cur[k-out_n],prior[k],prior[k-out_n])); break;
CASE(F_avg_first) cur[k] = raw[k] + (cur[k-out_n] >> 1); break;
CASE(F_paeth_first) cur[k] = (stbi__uint8) (raw[k] + paeth(cur[k-out_n],0,0)); break;
CASE(STBI__F_none) cur[k] = raw[k]; break;
CASE(STBI__F_sub) cur[k] = raw[k] + cur[k-out_n]; break;
CASE(STBI__F_up) cur[k] = raw[k] + prior[k]; break;
CASE(STBI__F_avg) cur[k] = raw[k] + ((prior[k] + cur[k-out_n])>>1); break;
CASE(STBI__F_paeth) cur[k] = (stbi__uint8) (raw[k] + stbi__paeth(cur[k-out_n],prior[k],prior[k-out_n])); break;
CASE(STBI__F_avg_first) cur[k] = raw[k] + (cur[k-out_n] >> 1); break;
CASE(STBI__F_paeth_first) cur[k] = (stbi__uint8) (raw[k] + stbi__paeth(cur[k-out_n],0,0)); break;
}
#undef CASE
}
......@@ -2539,12 +2539,12 @@ static int create_png_image_raw(png *a, stbi__uint8 *raw, stbi__uint32 raw_len,
return 1;
}
static int create_png_image(png *a, stbi__uint8 *raw, stbi__uint32 raw_len, int out_n, int interlaced)
static int stbi__create_png_image(stbi__png *a, stbi__uint8 *raw, stbi__uint32 raw_len, int out_n, int interlaced)
{
stbi__uint8 *final;
int p;
if (!interlaced)
return create_png_image_raw(a, raw, raw_len, out_n, a->s->img_x, a->s->img_y);
return stbi__create_png_image_raw(a, raw, raw_len, out_n, a->s->img_x, a->s->img_y);
// de-interlacing
final = (stbi__uint8 *) malloc(a->s->img_x * a->s->img_y * out_n);
......@@ -2558,7 +2558,7 @@ static int create_png_image(png *a, stbi__uint8 *raw, stbi__uint32 raw_len, int
x = (a->s->img_x - xorig[p] + xspc[p]-1) / xspc[p];
y = (a->s->img_y - yorig[p] + yspc[p]-1) / yspc[p];
if (x && y) {
if (!create_png_image_raw(a, raw, raw_len, out_n, x, y)) {
if (!stbi__create_png_image_raw(a, raw, raw_len, out_n, x, y)) {
free(final);
return 0;
}
......@@ -2576,7 +2576,7 @@ static int create_png_image(png *a, stbi__uint8 *raw, stbi__uint32 raw_len, int
return 1;
}
static int compute_transparency(png *z, stbi__uint8 tc[3], int out_n)
static int stbi__compute_transparency(stbi__png *z, stbi__uint8 tc[3], int out_n)
{
stbi__context *s = z->s;
stbi__uint32 i, pixel_count = s->img_x * s->img_y;
......@@ -2601,7 +2601,7 @@ static int compute_transparency(png *z, stbi__uint8 tc[3], int out_n)
return 1;
}
static int expand_palette(png *a, stbi__uint8 *palette, int len, int pal_img_n)
static int stbi__expand_png_palette(stbi__png *a, stbi__uint8 *palette, int len, int pal_img_n)
{
stbi__uint32 i, pixel_count = a->s->img_x * a->s->img_y;
stbi__uint8 *p, *temp_out, *orig = a->out;
......@@ -2638,19 +2638,20 @@ static int expand_palette(png *a, stbi__uint8 *palette, int len, int pal_img_n)
return 1;
}
static int stbi_unpremultiply_on_load = 0;
static int stbi_de_iphone_flag = 0;
static int stbi__unpremultiply_on_load = 0;
static int stbi__de_iphone_flag = 0;
void stbi_set_unpremultiply_on_load(int flag_true_if_should_unpremultiply)
STBIDEF void stbi_set_unpremultiply_on_load(int flag_true_if_should_unpremultiply)
{
stbi_unpremultiply_on_load = flag_true_if_should_unpremultiply;
stbi__unpremultiply_on_load = flag_true_if_should_unpremultiply;
}
void stbi_convert_iphone_png_to_rgb(int flag_true_if_should_convert)
STBIDEF void stbi_convert_iphone_png_to_rgb(int flag_true_if_should_convert)
{
stbi_de_iphone_flag = flag_true_if_should_convert;
stbi__de_iphone_flag = flag_true_if_should_convert;
}
static void stbi_de_iphone(png *z)
static void stbi__de_iphone(stbi__png *z)
{
stbi__context *s = z->s;
stbi__uint32 i, pixel_count = s->img_x * s->img_y;
......@@ -2665,7 +2666,7 @@ static void stbi_de_iphone(png *z)
}
} else {
assert(s->img_out_n == 4);
if (stbi_unpremultiply_on_load) {
if (stbi__unpremultiply_on_load) {
// convert bgr to rgb and unpremultiply
for (i=0; i < pixel_count; ++i) {
stbi__uint8 a = p[3];
......@@ -2692,7 +2693,7 @@ static void stbi_de_iphone(png *z)
}
}
static int parse_png_file(png *z, int scan, int req_comp)
static int stbi__parse_png_file(stbi__png *z, int scan, int req_comp)
{
stbi__uint8 palette[1024], pal_img_n=0;
stbi__uint8 has_trans=0, tc[3];
......@@ -2704,15 +2705,15 @@ static int parse_png_file(png *z, int scan, int req_comp)
z->idata = NULL;
z->out = NULL;
if (!check_png_header(s)) return 0;
if (!stbi__check_png_header(s)) return 0;
if (scan == SCAN_type) return 1;
for (;;) {
chunk c = get_chunk_header(s);
stbi__pngchunk c = stbi__get_chunk_header(s);
switch (c.type) {
case PNG_TYPE('C','g','B','I'):
iphone = stbi_de_iphone_flag;
iphone = stbi__de_iphone_flag;
stbi__skip(s, c.length);
break;
case PNG_TYPE('I','H','D','R'): {
......@@ -2806,17 +2807,17 @@ static int parse_png_file(png *z, int scan, int req_comp)
s->img_out_n = s->img_n+1;
else
s->img_out_n = s->img_n;
if (!create_png_image(z, z->expanded, raw_len, s->img_out_n, interlace)) return 0;
if (!stbi__create_png_image(z, z->expanded, raw_len, s->img_out_n, interlace)) return 0;
if (has_trans)
if (!compute_transparency(z, tc, s->img_out_n)) return 0;
if (!stbi__compute_transparency(z, tc, s->img_out_n)) return 0;
if (iphone && s->img_out_n > 2)
stbi_de_iphone(z);
stbi__de_iphone(z);
if (pal_img_n) {
// pal_img_n == 3 or 4
s->img_n = pal_img_n; // record the actual colors we had
s->img_out_n = pal_img_n;
if (req_comp >= 3) s->img_out_n = req_comp;
if (!expand_palette(z, palette, pal_len, s->img_out_n))
if (!stbi__expand_png_palette(z, palette, pal_len, s->img_out_n))
return 0;
}
free(z->expanded); z->expanded = NULL;
......@@ -2829,27 +2830,27 @@ static int parse_png_file(png *z, int scan, int req_comp)
if ((c.type & (1 << 29)) == 0) {
#ifndef STBI_NO_FAILURE_STRINGS
// not threadsafe
static char invalid_chunk[] = "XXXX chunk not known";
static char invalid_chunk[] = "XXXX stbi__pngchunk not known";
invalid_chunk[0] = (stbi__uint8) (c.type >> 24);
invalid_chunk[1] = (stbi__uint8) (c.type >> 16);
invalid_chunk[2] = (stbi__uint8) (c.type >> 8);
invalid_chunk[3] = (stbi__uint8) (c.type >> 0);
#endif
return stbi__err(invalid_chunk, "PNG not supported: unknown chunk type");
return stbi__err(invalid_chunk, "PNG not supported: unknown stbi__pngchunk type");
}
stbi__skip(s, c.length);
break;
}
// end of chunk, read and stbi__skip CRC
// end of stbi__pngchunk, read and stbi__skip CRC
stbi__get32be(s);
}
}
static unsigned char *do_png(png *p, int *x, int *y, int *n, int req_comp)
static unsigned char *stbi__do_png(stbi__png *p, int *x, int *y, int *n, int req_comp)
{
unsigned char *result=NULL;
if (req_comp < 0 || req_comp > 4) return stbi__errpuc("bad req_comp", "Internal error");
if (parse_png_file(p, SCAN_load, req_comp)) {
if (stbi__parse_png_file(p, SCAN_load, req_comp)) {
result = p->out;
p->out = NULL;
if (req_comp && req_comp != p->s->img_out_n) {
......@@ -2870,22 +2871,22 @@ static unsigned char *do_png(png *p, int *x, int *y, int *n, int req_comp)
static unsigned char *stbi__png_load(stbi__context *s, int *x, int *y, int *comp, int req_comp)
{
png p;
stbi__png p;
p.s = s;
return do_png(&p, x,y,comp,req_comp);
return stbi__do_png(&p, x,y,comp,req_comp);
}
static int stbi__png_test(stbi__context *s)
{
int r;
r = check_png_header(s);
r = stbi__check_png_header(s);
stbi_rewind(s);
return r;
}
static int stbi_png_info_raw(png *p, int *x, int *y, int *comp)
static int stbi__png_info_raw(stbi__png *p, int *x, int *y, int *comp)
{
if (!parse_png_file(p, SCAN_header, 0)) {
if (!stbi__parse_png_file(p, SCAN_header, 0)) {
stbi_rewind( p->s );
return 0;
}
......@@ -2895,11 +2896,11 @@ static int stbi_png_info_raw(png *p, int *x, int *y, int *comp)
return 1;
}
static int stbi__png_info(stbi__context *s, int *x, int *y, int *comp)
static int stbi__png_info(stbi__context *s, int *x, int *y, int *comp)
{
png p;
stbi__png p;
p.s = s;
return stbi_png_info_raw(&p, x, y, comp);
return stbi__png_info_raw(&p, x, y, comp);
}
// Microsoft/Windows BMP image
......@@ -3330,7 +3331,7 @@ static stbi_uc *tga_load(stbi__context *s, int *x, int *y, int *comp, int req_co
// load the data
for (i=0; i < tga_width * tga_height; ++i)
{
// if I'm in RLE mode, do I need to get a RLE chunk?
// if I'm in RLE mode, do I need to get a RLE stbi__pngchunk?
if ( tga_is_RLE )
{
if ( RLE_count == 0 )
......
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