diff options
| author | Kostya Shishkov <kostya.shishkov@gmail.com> | 2013-05-31 21:09:27 +0200 |
|---|---|---|
| committer | Kostya Shishkov <kostya.shishkov@gmail.com> | 2013-06-01 06:36:47 +0200 |
| commit | 33f64fd5d588a82b8bae1b1b5ea627c0c80b01d6 (patch) | |
| tree | 2e2b426d18fc9044805b0fcc05b70239b17e6854 | |
| parent | 60f09c04d80a31126f7eeaa669280887c5f4bc71 (diff) | |
| download | ffmpeg-33f64fd5d588a82b8bae1b1b5ea627c0c80b01d6.tar.gz | |
indeo4: expand allowed quantiser range
Indeo 4 has quantiser range 0-31 instead of 0-23 for Indeo 5, and clipping
quantiser leads to incorrect quantisation and DC prediction on low-quality
videos.
This fixes bug 259.
| -rw-r--r-- | libavcodec/ivi_common.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/libavcodec/ivi_common.c b/libavcodec/ivi_common.c index f11b7292ef..f7e241bf91 100644 --- a/libavcodec/ivi_common.c +++ b/libavcodec/ivi_common.c @@ -418,7 +418,11 @@ static int ivi_decode_blocks(GetBitContext *gb, IVIBandDesc *band, IVITile *tile cbp = mb->cbp; buf_offs = mb->buf_offs; - quant = av_clip(band->glob_quant + mb->q_delta, 0, 23); + quant = band->glob_quant + mb->q_delta; + if (avctx->codec_id == AV_CODEC_ID_INDEO4) + quant = av_clip(quant, 0, 31); + else + quant = av_clip(quant, 0, 23); base_tab = is_intra ? band->intra_base : band->inter_base; scale_tab = is_intra ? band->intra_scale : band->inter_scale; |