diff options
| author | Martin Storsjö <martin@martin.st> | 2014-06-06 12:03:09 +0300 |
|---|---|---|
| committer | Michael Niedermayer <michaelni@gmx.at> | 2014-06-06 17:08:21 +0200 |
| commit | fa8f060b75bf9074792a0f9ff4ed002652ef62b8 (patch) | |
| tree | 886251304a86ddecc841d56a0bf02022104fee1e | |
| parent | fb7646d92cba547b88ce82bfcc093eb57caf1dde (diff) | |
| download | ffmpeg-fa8f060b75bf9074792a0f9ff4ed002652ef62b8.tar.gz | |
adpcm: Write the proper predictor in trellis mode in IMA QT
The actual predictor value, set by the trellis code, never
was written back into the variable that was written into
the block header. This was accidentally removed in b304244b.
This significantly improves the audio quality of the trellis
case, which was plain broken since b304244b.
Encoding IMA QT with trellis still actually gives a slightly
worse quality than without trellis, since the trellis encoder
doesn't use the exact same way of rounding as in
adpcm_ima_qt_compress_sample and adpcm_ima_qt_expand_nibble.
Fixes part of Ticket3701
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
| -rw-r--r-- | libavcodec/adpcmenc.c | 1 | ||||
| -rw-r--r-- | tests/ref/acodec/adpcm-ima_qt-trellis | 6 |
2 files changed, 4 insertions, 3 deletions
diff --git a/libavcodec/adpcmenc.c b/libavcodec/adpcmenc.c index bfcce328ef..da149a3962 100644 --- a/libavcodec/adpcmenc.c +++ b/libavcodec/adpcmenc.c @@ -553,6 +553,7 @@ static int adpcm_encode_frame(AVCodecContext *avctx, AVPacket *avpkt, 64, 1); for (i = 0; i < 64; i++) put_bits(&pb, 4, buf[i ^ 1]); + status->prev_sample = status->predictor; } else { for (i = 0; i < 64; i += 2) { int t1, t2; diff --git a/tests/ref/acodec/adpcm-ima_qt-trellis b/tests/ref/acodec/adpcm-ima_qt-trellis index 796273ab2f..0a09965e1e 100644 --- a/tests/ref/acodec/adpcm-ima_qt-trellis +++ b/tests/ref/acodec/adpcm-ima_qt-trellis @@ -1,4 +1,4 @@ -9adceae86367ee131ca18f3fdf867d87 *tests/data/fate/acodec-adpcm-ima_qt-trellis.aiff +15f895c2e7119714f94333e3214d8426 *tests/data/fate/acodec-adpcm-ima_qt-trellis.aiff 281252 tests/data/fate/acodec-adpcm-ima_qt-trellis.aiff -3f53c10d523f26093103b058baada98c *tests/data/fate/acodec-adpcm-ima_qt-trellis.out.wav -stddev: 862.02 PSNR: 37.62 MAXDIFF:23859 bytes: 1058400/ 1058560 +593d68369c87d4e3b7323b1bea3e9315 *tests/data/fate/acodec-adpcm-ima_qt-trellis.out.wav +stddev: 716.74 PSNR: 39.22 MAXDIFF:29633 bytes: 1058400/ 1058560 |