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| author | Michael Niedermayer <michael@niedermayer.cc> | 2022-05-03 18:30:59 +0200 |
|---|---|---|
| committer | Michael Niedermayer <michael@niedermayer.cc> | 2022-07-07 21:52:52 +0200 |
| commit | 08e82e5b572b440f4faf160d2eac923ca47a59f8 (patch) | |
| tree | 90982d829f61e95655469c04f8edb0b457adf7cc | |
| parent | 5c2fa59f3272360e7df7b69fce722ac06017e371 (diff) | |
| download | ffmpeg-08e82e5b572b440f4faf160d2eac923ca47a59f8.tar.gz | |
avcodec/smacker: Optimize constant 16bit audio output
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Reviewed-by: Tomas Härdin <tjoppen@acc.umu.se>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
| -rw-r--r-- | libavcodec/smacker.c | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/libavcodec/smacker.c b/libavcodec/smacker.c index 179c70f1ee..5d94a54179 100644 --- a/libavcodec/smacker.c +++ b/libavcodec/smacker.c @@ -601,7 +601,7 @@ static int smka_decode_frame(AVCodecContext *avctx, AVFrame *frame, int i, res, ret; int unp_size; int bits, stereo; - unsigned pred[2], val; + unsigned pred[2], val, val2; if (buf_size <= 4) { av_log(avctx, AV_LOG_ERROR, "packet is too small\n"); @@ -672,7 +672,11 @@ static int smka_decode_frame(AVCodecContext *avctx, AVFrame *frame, pred[i] = av_bswap16(get_bits(&gb, 16)); for(i = 0; i <= stereo; i++) *samples++ = pred[i]; - for(; i < unp_size / 2; i++) { + unp_size /= 2; + + if (vlc[0 ].table || vlc[ 1].table || + vlc[2*stereo].table || vlc[2*stereo+1].table) { + for(; i < unp_size ; i++) { unsigned idx = 2 * (i & stereo); if (get_bits_left(&gb) < 0) { ret = AVERROR_INVALIDDATA; @@ -691,6 +695,22 @@ static int smka_decode_frame(AVCodecContext *avctx, AVFrame *frame, pred[idx / 2] += val; *samples++ = pred[idx / 2]; } + } else if (stereo) { + val = 256*values[1] + values[0]; + val2 = 256*values[3] + values[2]; + for(; i < unp_size; i+=2) { + pred[0] += val; + pred[1] += val2; + *samples++ = pred[0]; + *samples++ = pred[1]; + } + } else { + val = 256*values[1] + values[0]; + for(; i < unp_size; i++) { + pred[0] += val; + *samples++ = pred[0]; + } + } } else { //8-bit data for(i = stereo; i >= 0; i--) pred[i] = get_bits(&gb, 8); |