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fixed mpeg2 non intra dequant - fixed MPEG1 and 2 matrix parsing

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Originally committed as revision 76 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Fabrice Bellard 2001-08-12 00:52:01 +00:00
parent d753173a55
commit 25ed7f9235
1 changed files with 33 additions and 11 deletions
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44
libavcodec/mpeg12.c
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@ -554,6 +554,7 @@ static int mpeg_decode_mb(MpegEncContext *s,
s->mv_dir = MV_DIR_FORWARD;
s->mv[0][0][0] = s->mv[0][0][1] = 0;
s->last_mv[0][0][0] = s->last_mv[0][0][1] = 0;
s->last_mv[0][1][0] = s->last_mv[0][1][1] = 0;
} else {
/* if B type, reuse previous vectors and directions */
s->mv[0][0][0] = s->last_mv[0][0][0];
@ -981,7 +982,13 @@ static int mpeg2_decode_block_non_intra(MpegEncContext *s,
add_coef:
j = scan_table[i];
dprintf("%d: run=%d level=%d\n", n, run, level);
level = ((level * 2 + 1) * s->qscale * matrix[j]) / 32;
/* XXX: optimize */
if (level > 0) {
level = ((level * 2 + 1) * s->qscale * matrix[j]) >> 5;
} else {
level = ((-level * 2 + 1) * s->qscale * matrix[j]) >> 5;
level = -level;
}
/* XXX: is it really necessary to saturate since the encoder
knows whats going on ? */
mismatch ^= level;
@ -1029,7 +1036,7 @@ static int mpeg2_decode_block_intra(MpegEncContext *s,
matrix = s->intra_matrix;
else
matrix = s->chroma_intra_matrix;
/* now quantify & encode AC coefs */
for(;;) {
code = get_vlc(&s->gb, &rl->vlc);
@ -1183,10 +1190,12 @@ static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
{
int i, v, j;
dprintf("matrix extension\n");
if (get_bits1(&s->gb)) {
for(i=0;i<64;i++) {
v = get_bits(&s->gb, 8);
j = block_permute_op(i);
j = zigzag_direct[i];
s->intra_matrix[j] = v;
s->chroma_intra_matrix[j] = v;
}
@ -1194,7 +1203,7 @@ static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
if (get_bits1(&s->gb)) {
for(i=0;i<64;i++) {
v = get_bits(&s->gb, 8);
j = block_permute_op(i);
j = zigzag_direct[i];
s->non_intra_matrix[j] = v;
s->chroma_non_intra_matrix[j] = v;
}
@ -1202,14 +1211,14 @@ static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
if (get_bits1(&s->gb)) {
for(i=0;i<64;i++) {
v = get_bits(&s->gb, 8);
j = block_permute_op(i);
j = zigzag_direct[i];
s->chroma_intra_matrix[j] = v;
}
}
if (get_bits1(&s->gb)) {
for(i=0;i<64;i++) {
v = get_bits(&s->gb, 8);
j = block_permute_op(i);
j = zigzag_direct[i];
s->chroma_non_intra_matrix[j] = v;
}
}
@ -1234,10 +1243,11 @@ static void mpeg_decode_picture_coding_extension(MpegEncContext *s)
s->chroma_420_type = get_bits1(&s->gb);
s->progressive_frame = get_bits1(&s->gb);
/* composite display not parsed */
dprintf("dc_preci=%d\n", s->intra_dc_precision);
dprintf("pict_structure=%d\n", s->picture_structure);
dprintf("intra_dc_precion=%d\n", s->intra_dc_precision);
dprintf("picture_structure=%d\n", s->picture_structure);
dprintf("conceal=%d\n", s->concealment_motion_vectors);
dprintf("intrafmt=%d\n", s->intra_vlc_format);
dprintf("intra_vlc_format=%d\n", s->intra_vlc_format);
dprintf("alternate_scan=%d\n", s->alternate_scan);
dprintf("frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
}
@ -1402,10 +1412,16 @@ static int mpeg1_decode_sequence(AVCodecContext *avctx,
if (get_bits1(&s->gb)) {
for(i=0;i<64;i++) {
v = get_bits(&s->gb, 8);
j = block_permute_op(i);
j = zigzag_direct[i];
s->intra_matrix[j] = v;
s->chroma_intra_matrix[j] = v;
}
#ifdef DEBUG
dprintf("intra matrix present\n");
for(i=0;i<64;i++)
dprintf(" %d", s->intra_matrix[zigzag_direct[i]]);
printf("\n");
#endif
} else {
for(i=0;i<64;i++) {
v = default_intra_matrix[i];
@ -1416,10 +1432,16 @@ static int mpeg1_decode_sequence(AVCodecContext *avctx,
if (get_bits1(&s->gb)) {
for(i=0;i<64;i++) {
v = get_bits(&s->gb, 8);
j = block_permute_op(i);
j = zigzag_direct[i];
s->non_intra_matrix[j] = v;
s->chroma_non_intra_matrix[j] = v;
}
#ifdef DEBUG
dprintf("non intra matrix present\n");
for(i=0;i<64;i++)
dprintf(" %d", s->non_intra_matrix[zigzag_direct[i]]);
printf("\n");
#endif
} else {
for(i=0;i<64;i++) {
v = default_non_intra_matrix[i];