h261 decoder by (Maarten Daniels <maarten.daniels at student dot luc dot ac dot be>)

Originally committed as revision 3176 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/Makefile

@@ -55,7 +55,7 @@ ASM_OBJS=
 
 # codecs which are patented in some non free countries like the us
 ifeq ($(CONFIG_RISKY),yes)
-OBJS+= h263.o msmpeg4.o h263dec.o svq1.o rv10.o wmadec.o indeo3.o
+OBJS+= h263.o h261.o msmpeg4.o h263dec.o svq1.o rv10.o wmadec.o indeo3.o
 endif
 
 ifeq ($(HAVE_XVMC_ACCEL),yes)

libavcodec/allcodecs.c

@@ -84,6 +84,7 @@ void avcodec_register_all(void)
 #ifdef CONFIG_DECODERS
 #ifdef CONFIG_RISKY
     register_avcodec(&h263_decoder);
+    register_avcodec(&h261_decoder);
     register_avcodec(&mpeg4_decoder);
     register_avcodec(&msmpeg4v1_decoder);
     register_avcodec(&msmpeg4v2_decoder);
@@ -213,6 +214,7 @@ PCM_CODEC(CODEC_ID_ADPCM_EA, adpcm_g726);
     /* parsers */ 
     av_register_codec_parser(&mpegvideo_parser);
     av_register_codec_parser(&mpeg4video_parser);
+    av_register_codec_parser(&h261_parser);
     av_register_codec_parser(&h263_parser);
     av_register_codec_parser(&h264_parser);
 

libavcodec/avcodec.h

@@ -34,6 +34,7 @@ enum CodecID {
     CODEC_ID_MPEG1VIDEO,
     CODEC_ID_MPEG2VIDEO, /* prefered ID for MPEG Video 1 or 2 decoding */
     CODEC_ID_MPEG2VIDEO_XVMC,
+    CODEC_ID_H261,
     CODEC_ID_H263,
     CODEC_ID_RV10,
     CODEC_ID_RV20,
@@ -1724,6 +1725,7 @@ extern AVCodec zlib_encoder;
 extern AVCodec svq1_encoder;
 
 extern AVCodec h263_decoder;
+extern AVCodec h261_decoder;
 extern AVCodec mpeg4_decoder;
 extern AVCodec msmpeg4v1_decoder;
 extern AVCodec msmpeg4v2_decoder;
@@ -2124,6 +2126,7 @@ void av_parser_close(AVCodecParserContext *s);
 
 extern AVCodecParser mpegvideo_parser;
 extern AVCodecParser mpeg4video_parser;
+extern AVCodecParser h261_parser;
 extern AVCodecParser h263_parser;
 extern AVCodecParser h264_parser;
 extern AVCodecParser mpegaudio_parser;

libavcodec/dsputil.c

@@ -2360,6 +2360,36 @@ static void h263_h_loop_filter_c(uint8_t *src, int stride, int qscale){
     }
 }
 
+static void h261_v_loop_filter_c(uint8_t *dest,uint8_t *src, int stride){
+    int i,j,xy,yz;
+    int res;
+    for(i=0; i<8; i++){
+        for(j=1; j<7; j++){
+            xy = j * stride + i;
+            yz = j * 8 + i;
+            res = (int)src[yz-1*8] + ((int)(src[yz+0*8]) * 2) + (int)src[yz+1*8];
+            res +=2;
+            res >>=2;
+            dest[xy] = (uint8_t)res;
+        }
+    }
+}
+
+static void h261_h_loop_filter_c(uint8_t *dest,uint8_t *src, int stride){
+    int i,j,xy,yz;
+    int res;    
+    for(i=1; i<7; i++){
+        for(j=0; j<8; j++){
+            xy = j * stride + i;
+            yz = j * 8 + i;
+            res = (int)src[yz-1] + ((int)(src[yz]) *2) + (int)src[yz+1];
+            res+=2;
+            res>>=2;
+            dest[xy] = (uint8_t)res;
+        }
+    }
+}
+
 static inline int pix_abs16_c(void *v, uint8_t *pix1, uint8_t *pix2, int line_size, int h)
 {
     int s, i;
@@ -3295,6 +3325,9 @@ void dsputil_init(DSPContext* c, AVCodecContext *avctx)
     c->h263_h_loop_filter= h263_h_loop_filter_c;
     c->h263_v_loop_filter= h263_v_loop_filter_c;
     
+    c->h261_h_loop_filter= h261_h_loop_filter_c;
+    c->h261_v_loop_filter= h261_v_loop_filter_c;
+    
     c->try_8x8basis= try_8x8basis_c;
     c->add_8x8basis= add_8x8basis_c;
 

libavcodec/dsputil.h

@@ -261,6 +261,9 @@ typedef struct DSPContext {
     void (*h263_v_loop_filter)(uint8_t *src, int stride, int qscale);
     void (*h263_h_loop_filter)(uint8_t *src, int stride, int qscale);
 
+    void (*h261_v_loop_filter)(uint8_t *dest,uint8_t *src, int stride);
+    void (*h261_h_loop_filter)(uint8_t *dest,uint8_t *src, int stride);
+
     /* (I)DCT */
     void (*fdct)(DCTELEM *block/* align 16*/);
     void (*fdct248)(DCTELEM *block/* align 16*/);

libavcodec/h261data.h

+/**
+ * @file h261data.h
+ * H.261 tables.
+ */
+#define MB_TYPE_H261_FIL 0x800000
+
+// H.261 VLC table for macroblock addressing
+const uint8_t h261_mba_code[34] = {
+     1,  3,  2,  3,
+     2,  3,  2,  7,
+     6, 11, 10,  9,
+     8,  7,  6, 23,
+    22, 21, 20, 19,
+    18, 35, 34, 33,
+    32, 31, 30, 29,
+    28, 27, 26, 25,
+    24,
+    15             //(MBA stuffing)
+};
+
+const uint8_t h261_mba_bits[34] = {
+     1,  3,  3,  4,
+     4,  5,  5,  7,
+     7,  8,  8,  8,
+     8,  8,  8, 10,
+    10, 10, 10, 10,
+    10, 11, 11, 11,
+    11, 11, 11, 11,
+    11, 11, 11, 11,
+    11,
+    11            //(MBA stuffing)
+};
+
+//H.261 VLC table for macroblock type
+const uint8_t h261_mtype_code[10] = {
+    1,  1,  1,  1,
+    1,  1,  1,  1,
+    1,  1
+};
+
+const uint8_t h261_mtype_bits[10] = {
+    4,  7,  1,  5,
+    9,  8, 10,  3,
+    2,  6
+};
+
+static const int h261_mtype_map[10]= {
+        MB_TYPE_INTRA4x4,
+        MB_TYPE_INTRA4x4  |  MB_TYPE_QUANT,
+                                               MB_TYPE_CBP,
+                             MB_TYPE_QUANT  |  MB_TYPE_CBP,
+                                                               MB_TYPE_16x16,
+                                               MB_TYPE_CBP  |  MB_TYPE_16x16,
+                             MB_TYPE_QUANT  |  MB_TYPE_CBP  |  MB_TYPE_16x16,
+                                                               MB_TYPE_16x16  |  MB_TYPE_H261_FIL,
+                                               MB_TYPE_CBP  |  MB_TYPE_16x16  |  MB_TYPE_H261_FIL,
+                             MB_TYPE_QUANT  |  MB_TYPE_CBP  |  MB_TYPE_16x16  |  MB_TYPE_H261_FIL
+};
+
+//H.261 VLC table for motion vectors
+const uint8_t h261_mv_tab[17][2] = {
+    {1,1}, {1,2}, {1,3}, {1,4}, {3,6}, {5,7}, {4,7}, {3,7},
+    {11,9}, {10,9}, {9,9}, {17,10}, {16,10}, {15,10}, {14,10}, {13,10}, {12,10}
+};
+
+static const int mvmap[17] =
+{
+    0, -1, -2, -3, -4, -5, -6, -7, -8, -9, -10, -11, -12, -13, -14, -15, 16
+};
+
+//H.261 VLC table for coded block pattern
+const uint8_t h261_cbp_tab[63][2] =
+{
+    {11,5}, {9,5}, {13,6}, {13,4}, {23,7}, {19,7}, {31,8}, {12,4},
+    {22,7}, {18,7}, {30,8}, {19,5}, {27,8}, {23,8}, {19,8}, {11,4},
+    {21,7}, {17,7}, {29,8}, {17,5}, {25,8}, {21,8}, {17,8}, {15,6},
+    {15,8}, {13,8}, {3,9}, {15,5}, {11,8}, {7,8}, {7,9}, {10,4},
+    {20,7}, {16,7}, {28,8}, {14,6}, {14,8}, {12,8}, {2,9}, {16,5},
+    {24,8}, {20,8}, {16,8}, {14,5}, {10,8}, {6,8}, {6,9}, {18,5},
+    {26,8}, {22,8}, {18,8}, {13,5}, {9,8}, {5,8}, {5,9}, {12,5},
+    {8,8}, {4,8}, {4,9}, {7,3}, {10,5}, {8,5}, {12,6}
+};
+
+//H.261 VLC table for transform coefficients
+const uint16_t h261_tcoeff_vlc[65][2] = {
+{ 0x2, 2 }, { 0x3, 2 },{ 0x4, 4 },{ 0x5, 5 },
+{ 0x6, 7 },{ 0x26, 8 },{ 0x21, 8 },{ 0xa, 10 },
+{ 0x1d, 12 },{ 0x18, 12 },{ 0x13, 12 },{ 0x10 , 12 },
+{ 0x1a, 13},{ 0x19, 13 }, { 0x18, 13 }, { 0x17, 13 },
+{ 0x3, 3 }, { 0x6, 6 }, { 0x25 , 8 }, { 0xc, 10 },
+{ 0x1b, 12 }, { 0x16, 13 }, { 0x15, 13 }, { 0x5, 4},
+{ 0x4, 7}, { 0xb, 10 }, { 0x14, 12 }, { 0x14, 13 },
+{ 0x7, 5 }, { 0x24, 8 }, { 0x1c, 12 }, { 0x13, 13 },
+{ 0x6, 5 }, { 0xf, 10 }, { 0x12, 12}, { 0x7, 6},
+{ 0x9 , 10 }, { 0x12, 13 }, { 0x5, 6 }, { 0x1e, 12 },
+{ 0x4, 6 }, { 0x15, 12 }, { 0x7, 7 }, { 0x11, 12},
+{ 0x5, 7 }, { 0x11, 13 }, { 0x27, 8 }, { 0x10, 13 },
+{ 0x23, 8 }, { 0x22, 8 }, { 0x20, 8 }, { 0xe , 10 },
+{ 0xd, 10 }, { 0x8, 10 },{ 0x1f, 12 }, { 0x1a, 12 },
+{ 0x19, 12 }, { 0x17, 12 }, { 0x16, 12}, { 0x1f, 13},
+{ 0x1e, 13 }, { 0x1d, 13 }, { 0x1c, 13}, { 0x1b, 13},
+{ 0x1, 6 }                                             //escape
+};
+
+const int8_t h261_tcoeff_level[64] = {
+    0,  1,  2,  3,  4,  5,  6,  7,
+    8,  9, 10, 11, 12, 13, 14, 15,
+    1,  2,  3,  4,  5,  6,  7,  1,
+    2,  3,  4,  5,  1,  2,  3,  4,
+    1,  2,  3,  1,  2,  3,  1,  2,
+    1,  2,  1,  2,  1,  2,  1,  2,
+    1,  1,  1,  1,  1,  1,  1,  1,
+    1,  1,  1,  1,  1,  1,  1,  1
+};
+
+const int8_t h261_tcoeff_run[64] = {
+    0,
+    0,  0,  0,  0,  0,  0,  0,  0,
+    0,  0,  0,  0,  0,  0,  0,  1,
+    1,  1,  1,  1,  1,  1,  2,  2,
+    2,  2,  2,  3,  3,  3,  3,  4,
+    4,  4,  5,  5,  5,  6,  6,  7,
+    7,  8,  8,  9,  9, 10, 10, 11,
+   12, 13, 14, 15, 16, 17, 18, 19,
+   20, 21, 22, 23, 24, 25, 26
+};
+
+static RLTable h261_rl_tcoeff = {
+    64,
+    64,
+    h261_tcoeff_vlc,
+    h261_tcoeff_run,
+    h261_tcoeff_level,
+};

libavcodec/mpegvideo.c

@@ -53,6 +53,10 @@ static void dct_unquantize_h263_intra_c(MpegEncContext *s,
                                   DCTELEM *block, int n, int qscale);
 static void dct_unquantize_h263_inter_c(MpegEncContext *s, 
                                   DCTELEM *block, int n, int qscale);
+static void dct_unquantize_h261_intra_c(MpegEncContext *s, 
+                                  DCTELEM *block, int n, int qscale);
+static void dct_unquantize_h261_inter_c(MpegEncContext *s, 
+                                  DCTELEM *block, int n, int qscale);
 static void draw_edges_c(uint8_t *buf, int wrap, int width, int height, int w);
 #ifdef CONFIG_ENCODERS
 static int dct_quantize_c(MpegEncContext *s, DCTELEM *block, int n, int qscale, int *overflow);
@@ -215,6 +219,8 @@ int DCT_common_init(MpegEncContext *s)
 {
     s->dct_unquantize_h263_intra = dct_unquantize_h263_intra_c;
     s->dct_unquantize_h263_inter = dct_unquantize_h263_inter_c;
+    s->dct_unquantize_h261_intra = dct_unquantize_h261_intra_c;
+    s->dct_unquantize_h261_inter = dct_unquantize_h261_inter_c;
     s->dct_unquantize_mpeg1_intra = dct_unquantize_mpeg1_intra_c;
     s->dct_unquantize_mpeg1_inter = dct_unquantize_mpeg1_inter_c;
     s->dct_unquantize_mpeg2_intra = dct_unquantize_mpeg2_intra_c;
@@ -1454,6 +1460,9 @@ alloc:
     }else if(s->out_format == FMT_H263){
         s->dct_unquantize_intra = s->dct_unquantize_h263_intra;
         s->dct_unquantize_inter = s->dct_unquantize_h263_inter;
+    }else if(s->out_format == FMT_H261){
+        s->dct_unquantize_intra = s->dct_unquantize_h261_intra;
+        s->dct_unquantize_inter = s->dct_unquantize_h261_inter;
     }else{
         s->dct_unquantize_intra = s->dct_unquantize_mpeg1_intra;
         s->dct_unquantize_inter = s->dct_unquantize_mpeg1_inter;
@@ -2494,6 +2503,12 @@ if(s->quarter_sample)
             uvsrc_x = src_x>>1;
             uvsrc_y = src_y>>1;
         }
+    }else if(s->out_format == FMT_H261){//even chroma mv's are full pel in H261
+        mx = motion_x / 4;
+        my = motion_y / 4;
+        uvdxy = 0;
+        uvsrc_x = s->mb_x*8 + mx;
+        uvsrc_y = s->mb_y*8 + my;
     } else {
         mx = motion_x / 2;
         my = motion_y / 2;
@@ -5782,6 +5797,59 @@ static void dct_unquantize_h263_inter_c(MpegEncContext *s,
     }
 }
 
+static void dct_unquantize_h261_intra_c(MpegEncContext *s, 
+                                  DCTELEM *block, int n, int qscale)
+{
+    int i, level, odd;
+    int nCoeffs;
+    
+    assert(s->block_last_index[n]>=0);
+    
+    if (n < 4) 
+        block[0] = block[0] * s->y_dc_scale;
+    else
+        block[0] = block[0] * s->c_dc_scale;
+    odd = qscale & 0x1;
+    nCoeffs= s->inter_scantable.raster_end[ s->block_last_index[n] ];
+
+    for(i=1; i<=nCoeffs; i++){
+        level = block[i];
+        if (level){
+            if (level < 0){
+                level = qscale * ((level << 1) - 1) + (~odd);
+            }else{
+                level = qscale * ((level << 1) + 1) - (~odd);
+            }
+        }
+        block[i] = level;
+    }
+}
+
+static void dct_unquantize_h261_inter_c(MpegEncContext *s, 
+                                  DCTELEM *block, int n, int qscale)
+{
+    int i, level, odd;
+    int nCoeffs;
+    
+    assert(s->block_last_index[n]>=0);
+    
+    odd = qscale & 0x1;
+    
+    nCoeffs= s->inter_scantable.raster_end[ s->block_last_index[n] ];
+
+    for(i=0; i<=nCoeffs; i++){
+        level = block[i];
+        if (level){
+            if (level < 0){
+                level = qscale * ((level << 1) - 1) + (~odd);
+            }else{
+                level = qscale * ((level << 1) + 1) - (~odd);
+            }
+        }
+        block[i] = level;
+    }
+}
+
 static const AVOption mpeg4_options[] =
 {
     AVOPTION_CODEC_INT("bitrate", "desired video bitrate", bit_rate, 4, 240000000, 800000),

libavcodec/mpegvideo.h

@@ -32,6 +32,7 @@
 
 enum OutputFormat {
     FMT_MPEG1,
+    FMT_H261,
     FMT_H263,
     FMT_MJPEG, 
     FMT_H264,
@@ -703,6 +704,10 @@ typedef struct MpegEncContext {
                            DCTELEM *block/*align 16*/, int n, int qscale);
     void (*dct_unquantize_h263_inter)(struct MpegEncContext *s, 
                            DCTELEM *block/*align 16*/, int n, int qscale);
+    void (*dct_unquantize_h261_intra)(struct MpegEncContext *s, 
+                           DCTELEM *block/*align 16*/, int n, int qscale);
+    void (*dct_unquantize_h261_inter)(struct MpegEncContext *s, 
+                           DCTELEM *block/*align 16*/, int n, int qscale);
     void (*dct_unquantize_intra)(struct MpegEncContext *s, // unquantizer to use (mpeg4 can use both)
                            DCTELEM *block/*align 16*/, int n, int qscale);
     void (*dct_unquantize_inter)(struct MpegEncContext *s, // unquantizer to use (mpeg4 can use both)

libavformat/raw.c

@@ -259,6 +259,21 @@ static int h263_probe(AVProbeData *p)
     return 0;
 }
 
+static int h261_probe(AVProbeData *p)
+{
+    int code;
+    const uint8_t *d;
+
+    if (p->buf_size < 6)
+        return 0;
+    d = p->buf;
+    code = (d[0] << 12) | (d[1] << 4) | (d[2] >> 4);
+    if (code == 0x10) {
+        return 50;
+    }
+    return 0;
+}
+
 AVInputFormat ac3_iformat = {
     "ac3",
     "raw ac3",
@@ -285,6 +300,18 @@ AVOutputFormat ac3_oformat = {
 };
 #endif //CONFIG_ENCODERS
 
+AVInputFormat h261_iformat = {
+    "h261",
+    "raw h261",
+    0,
+    h261_probe,
+    video_read_header,
+    raw_read_partial_packet,
+    raw_read_close,
+    .extensions = "h261",
+    .value = CODEC_ID_H261,
+};
+
 AVInputFormat h263_iformat = {
     "h263",
     "raw h263",
@@ -586,6 +613,8 @@ int raw_init(void)
     av_register_input_format(&ac3_iformat);
     av_register_output_format(&ac3_oformat);
 
+    av_register_input_format(&h261_iformat);
+
     av_register_input_format(&h263_iformat);
     av_register_output_format(&h263_oformat);