H261 fixing and cleaning:

-corrected wrong value in mv data
 -set correct mb_type after adjusting index
 -don't use H263 loop filter when the loop filter flag is set but when
  using the H261 encoder
 -use the same unquantizer as H263 (which is optimized btw)
 -removed unused members in H261Context
patch by (Maarten Daniels <maarten.daniels >at< luc >dot< ac >dot< be>)

regression test checksum update by me

Originally committed as revision 3669 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/h261.c

@@ -53,8 +53,6 @@ typedef struct H261Context{
     int current_mv_x;
     int current_mv_y;
     int gob_number;
-    int bits_left; //8 - nr of bits left of the following frame in the last byte in this frame
-    int last_bits; //bits left of the following frame in the last byte in this frame
     int gob_start_code_skipped; // 1 if gob start code is already read before gob header is read
 }H261Context;
 
@@ -176,7 +174,7 @@ static void h261_encode_motion(H261Context * h, int val){
         put_bits(&s->pb,h261_mv_tab[code][1],h261_mv_tab[code][0]);
     } 
     else{
-        if(val > 16)
+        if(val > 15)
             val -=32;
         if(val < -16)
             val+=32;
@@ -847,24 +845,12 @@ static int h261_decode_gob(H261Context *h){
 }
 
 static int h261_find_frame_end(ParseContext *pc, AVCodecContext* avctx, const uint8_t *buf, int buf_size){
-    int vop_found, i, j, bits_left, last_bits;
+    int vop_found, i, j;
     uint32_t state;
 
-    H261Context *h = avctx->priv_data;
-
-    if(h){
-        bits_left = h->bits_left;
-        last_bits = h->last_bits;
-    }
-    else{
-        bits_left = 0;
-        last_bits = 0;
-    }
-
     vop_found= pc->frame_start_found;
     state= pc->state;
-    if(bits_left!=0 && !vop_found)
-        state = state << (8-bits_left) | last_bits;
+   
     i=0;
     if(!vop_found){
         for(i=0; i<buf_size; i++){

libavcodec/h261data.h

@@ -67,7 +67,7 @@ const uint8_t h261_mv_tab[17][2] = {
 
 static const int mvmap[17] =
 {
-    0, -1, -2, -3, -4, -5, -6, -7, -8, -9, -10, -11, -12, -13, -14, -15, 16
+    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

libavcodec/mpegvideo.c

@@ -53,10 +53,6 @@ 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);
@@ -219,8 +215,6 @@ 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;
@@ -1482,12 +1476,9 @@ alloc:
     if(s->mpeg_quant || s->codec_id == CODEC_ID_MPEG2VIDEO){
         s->dct_unquantize_intra = s->dct_unquantize_mpeg2_intra;
         s->dct_unquantize_inter = s->dct_unquantize_mpeg2_inter;
-    }else if(s->out_format == FMT_H263){
+    }else if(s->out_format == FMT_H263 || s->out_format == FMT_H261){
         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;
@@ -4517,6 +4508,7 @@ static int encode_thread(AVCodecContext *c, void *arg){
             if(s->codec_id == CODEC_ID_H261){
                 ff_h261_reorder_mb_index(s);
                 xy= s->mb_y*s->mb_stride + s->mb_x;
+                mb_type= s->mb_type[xy];
             }
 
             /* write gob / video packet header  */
@@ -4990,8 +4982,10 @@ static int encode_thread(AVCodecContext *c, void *arg){
                     s, s->new_picture    .data[2] + s->mb_x*8  + s->mb_y*s->uvlinesize*8,
                     s->dest[2], w>>1, h>>1, s->uvlinesize);
             }
-            if(s->loop_filter)
-                ff_h263_loop_filter(s);
+            if(s->loop_filter){
+                if(s->out_format == FMT_H263)
+                    ff_h263_loop_filter(s);
+            }
 //printf("MB %d %d bits\n", s->mb_x+s->mb_y*s->mb_stride, put_bits_count(&s->pb));
         }
     }
@@ -6250,59 +6244,6 @@ 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, even;
-    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;
-    even = (qscale & 1)^1;
-    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) + even;
-            }else{
-                level = qscale * ((level << 1) + 1) - even;
-            }
-        }
-        block[i] = level;
-    }
-}
-
-static void dct_unquantize_h261_inter_c(MpegEncContext *s, 
-                                  DCTELEM *block, int n, int qscale)
-{
-    int i, level, even;
-    int nCoeffs;
-    
-    assert(s->block_last_index[n]>=0);
-
-    even = (qscale & 1)^1;
-    
-    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) + even;
-            }else{
-                level = qscale * ((level << 1) + 1) - even;
-            }
-        }
-        block[i] = level;
-    }
-}
-
 static const AVOption mpeg4_options[] =
 {
     AVOPTION_CODEC_INT("bitrate", "desired video bitrate", bit_rate, 4, 240000000, 800000),

tests/ffmpeg.regression.ref

@@ -35,10 +35,10 @@ a5bd577163968edab00058f2c8d5efab *./data/a-wmv2.avi
 682132 ./data/a-wmv2.avi
 09253222ab4eb95628c931a86006a2b1 *./data/out.yuv
 stddev:  8.02 PSNR:30.04 bytes:7602176
-c12437d78325d6634ff77a49bf1869e8 *./data/a-h261.avi
-779222 ./data/a-h261.avi
-1dd0be7be463c1a338d1b848e926a0b8 *./data/out.yuv
-stddev:  9.17 PSNR:28.87 bytes:7602176
+bcf34887269746ac7973f88cde336609 *./data/a-h261.avi
+735098 ./data/a-h261.avi
+0a6e6dd4f09df9fe77ff29581c1a39c3 *./data/out.yuv
+stddev:  9.14 PSNR:28.90 bytes:7602176
 fa556e599181bf9328a811a1ce9aa022 *./data/a-h263.avi
 682226 ./data/a-h263.avi
 f2b7fcff9de17f5aecfeb1090fe1963b *./data/out.yuv

tests/rotozoom.regression.ref

@@ -35,10 +35,10 @@ stddev:  5.33 PSNR:33.58 bytes:7602176
 129214 ./data/a-wmv2.avi
 f80d2809e79af3ebcfe831deab9af03c *./data/out.yuv
 stddev:  5.33 PSNR:33.58 bytes:7602176
-41050f885f7ea9594643e5dbf8ea30da *./data/a-h261.avi
-193452 ./data/a-h261.avi
-c74fbf0b0faf1124e172413c059ab45a *./data/out.yuv
-stddev:  6.40 PSNR:31.99 bytes:7602176
+631f4daabb4f639e8dec18bbb58dae79 *./data/a-h261.avi
+191124 ./data/a-h261.avi
+452714d0883f555e831888de0be1fc49 *./data/out.yuv
+stddev:  6.39 PSNR:32.00 bytes:7602176
 ef053b1fec77a49eb8a27510b81e4041 *./data/a-h263.avi
 159596 ./data/a-h263.avi
 7ec66fb7dd4e5dddd3820c668d6636aa *./data/out.yuv