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author | Vittorio Giovara <vittorio.giovara@gmail.com> | 2016-01-25 12:56:11 -0500 |
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committer | Diego Biurrun <diego@biurrun.de> | 2016-02-09 20:04:59 +0100 |
commit | 7c25ffe070c286874a8c3513f7504b90e1626b0c (patch) | |
tree | 8532cb662850f35681472362c3a1eab3fa597d77 /libavcodec/mpeg12dec.c | |
parent | 249827f736db4c94dfcb24a3883aa4c04f9b119b (diff) | |
download | ffmpeg-7c25ffe070c286874a8c3513f7504b90e1626b0c.tar.gz |
mpeg1: Make intra-block decoding independent of MpegEncContext
This allows untangling the eatqi decoder from the MPEG-1 decoder.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
Signed-off-by: Diego Biurrun <diego@biurrun.de>
Diffstat (limited to 'libavcodec/mpeg12dec.c')
-rw-r--r-- | libavcodec/mpeg12dec.c | 108 |
1 files changed, 13 insertions, 95 deletions
diff --git a/libavcodec/mpeg12dec.c b/libavcodec/mpeg12dec.c index 2a88756119..c1f35274cc 100644 --- a/libavcodec/mpeg12dec.c +++ b/libavcodec/mpeg12dec.c @@ -138,99 +138,6 @@ static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred) } \ } while (0) -static inline int mpeg1_decode_block_intra(MpegEncContext *s, - int16_t *block, int index) -{ - int dc, diff, i = 0, component; - RLTable *rl = &ff_rl_mpeg1; - uint8_t *const scantable = s->intra_scantable.permutated; - const uint16_t *quant_matrix = s->intra_matrix; - const int qscale = s->qscale; - - /* DC coefficient */ - component = index <= 3 ? 0 : index - 4 + 1; - - diff = decode_dc(&s->gb, component); - if (diff >= 0xffff) - return AVERROR_INVALIDDATA; - - dc = s->last_dc[component]; - dc += diff; - s->last_dc[component] = dc; - - block[0] = dc * quant_matrix[0]; - - { - OPEN_READER(re, &s->gb); - /* now quantify & encode AC coefficients */ - while (1) { - int level, run, j; - - UPDATE_CACHE(re, &s->gb); - GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], - TEX_VLC_BITS, 2, 0); - - if (level == 127) { - break; - } else if (level != 0) { - i += run; - if (i > MAX_INDEX) - break; - - j = scantable[i]; - level = (level * qscale * quant_matrix[j]) >> 4; - level = (level - 1) | 1; - level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - - SHOW_SBITS(re, &s->gb, 1); - LAST_SKIP_BITS(re, &s->gb, 1); - } else { - /* escape */ - run = SHOW_UBITS(re, &s->gb, 6) + 1; - LAST_SKIP_BITS(re, &s->gb, 6); - UPDATE_CACHE(re, &s->gb); - level = SHOW_SBITS(re, &s->gb, 8); - SKIP_BITS(re, &s->gb, 8); - - if (level == -128) { - level = SHOW_UBITS(re, &s->gb, 8) - 256; - LAST_SKIP_BITS(re, &s->gb, 8); - } else if (level == 0) { - level = SHOW_UBITS(re, &s->gb, 8); - LAST_SKIP_BITS(re, &s->gb, 8); - } - - i += run; - if (i > MAX_INDEX) - break; - - j = scantable[i]; - if (level < 0) { - level = -level; - level = (level * qscale * quant_matrix[j]) >> 4; - level = (level - 1) | 1; - level = -level; - } else { - level = (level * qscale * quant_matrix[j]) >> 4; - level = (level - 1) | 1; - } - } - - block[j] = level; - } - CLOSE_READER(re, &s->gb); - } - - check_scantable_index(s, i); - - s->block_last_index[index] = i; - return 0; -} - -int ff_mpeg1_decode_block_intra(MpegEncContext *s, int16_t *block, int index) -{ - return mpeg1_decode_block_intra(s, block, index); -} - static inline int mpeg1_decode_block_inter(MpegEncContext *s, int16_t *block, int n) { @@ -874,9 +781,20 @@ FF_ENABLE_DEPRECATION_WARNINGS return ret; } } else { - for (i = 0; i < 6; i++) - if ((ret = mpeg1_decode_block_intra(s, *s->pblocks[i], i)) < 0) + for (i = 0; i < 6; i++) { + ret = ff_mpeg1_decode_block_intra(&s->gb, + s->intra_matrix, + s->intra_scantable.permutated, + s->last_dc, *s->pblocks[i], + i, s->qscale); + if (ret < 0) { + av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", + s->mb_x, s->mb_y); return ret; + } + + s->block_last_index[i] = ret; + } } } else { if (mb_type & MB_TYPE_ZERO_MV) { |