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| author | Paul B Mahol <onemda@gmail.com> | 2012-11-07 03:22:27 +0000 |
|---|---|---|
| committer | Paul B Mahol <onemda@gmail.com> | 2012-11-07 13:03:50 +0000 |
| commit | 08101e62cbde7df9749e297e53915e58195bc1b3 (patch) | |
| tree | e89901013013bf617d39eab9f0b64df38758e895 /libavcodec/adpcm.c | |
| parent | a373f352728c5f56b6679ea8ab668d830811c324 (diff) | |
| download | ffmpeg-08101e62cbde7df9749e297e53915e58195bc1b3.tar.gz | |
adpcm: improve smjpeg decoding
Previous version had significant artifacts.
Signed-off-by: Paul B Mahol <onemda@gmail.com>
Diffstat (limited to 'libavcodec/adpcm.c')
| -rw-r--r-- | libavcodec/adpcm.c | 42 |
1 files changed, 22 insertions, 20 deletions
diff --git a/libavcodec/adpcm.c b/libavcodec/adpcm.c index 2dc3e6b50d..10da0062ed 100644 --- a/libavcodec/adpcm.c +++ b/libavcodec/adpcm.c @@ -1136,16 +1136,9 @@ static int adpcm_decode_frame(AVCodecContext *avctx, void *data, } break; case AV_CODEC_ID_ADPCM_IMA_AMV: - case AV_CODEC_ID_ADPCM_IMA_SMJPEG: - if (avctx->codec->id == AV_CODEC_ID_ADPCM_IMA_AMV) { - c->status[0].predictor = sign_extend(bytestream2_get_le16u(&gb), 16); - c->status[0].step_index = bytestream2_get_le16u(&gb); - bytestream2_skipu(&gb, 4); - } else { - c->status[0].predictor = sign_extend(bytestream2_get_be16u(&gb), 16); - c->status[0].step_index = bytestream2_get_byteu(&gb); - bytestream2_skipu(&gb, 1); - } + c->status[0].predictor = sign_extend(bytestream2_get_le16u(&gb), 16); + c->status[0].step_index = bytestream2_get_le16u(&gb); + bytestream2_skipu(&gb, 4); if (c->status[0].step_index > 88u) { av_log(avctx, AV_LOG_ERROR, "ERROR: step_index = %i\n", c->status[0].step_index); @@ -1153,18 +1146,27 @@ static int adpcm_decode_frame(AVCodecContext *avctx, void *data, } for (n = nb_samples >> (1 - st); n > 0; n--) { - int hi, lo, v = bytestream2_get_byteu(&gb); + int v = bytestream2_get_byteu(&gb); - if (avctx->codec->id == AV_CODEC_ID_ADPCM_IMA_AMV) { - hi = v & 0x0F; - lo = v >> 4; - } else { - lo = v & 0x0F; - hi = v >> 4; - } + *samples++ = adpcm_ima_expand_nibble(&c->status[0], v >> 4, 3); + *samples++ = adpcm_ima_expand_nibble(&c->status[0], v & 0xf, 3); + } + break; + case AV_CODEC_ID_ADPCM_IMA_SMJPEG: + c->status[0].predictor = sign_extend(bytestream2_get_be16u(&gb), 16); + c->status[0].step_index = bytestream2_get_byteu(&gb); + bytestream2_skipu(&gb, 1); + if (c->status[0].step_index > 88u) { + av_log(avctx, AV_LOG_ERROR, "ERROR: step_index = %i\n", + c->status[0].step_index); + return AVERROR_INVALIDDATA; + } + + for (n = nb_samples >> (1 - st); n > 0; n--) { + int v = bytestream2_get_byteu(&gb); - *samples++ = adpcm_ima_expand_nibble(&c->status[0], lo, 3); - *samples++ = adpcm_ima_expand_nibble(&c->status[0], hi, 3); + *samples++ = adpcm_ima_qt_expand_nibble(&c->status[0], v >> 4, 3); + *samples++ = adpcm_ima_qt_expand_nibble(&c->status[0], v & 0xf, 3); } break; case AV_CODEC_ID_ADPCM_CT: |