[FFmpeg-cvslog] apedec: do not buffer decoded samples over AVPackets

Rafaël Carré git at videolan.org
Tue Jun 3 02:49:38 CEST 2014

ffmpeg | branch: release/0.10 | Rafaël Carré <funman at videolan.org> | Tue Aug 27 17:35:49 2013 +0200| [65c3593792a9702d9e4135bba46b1ca186afed6c] | committer: Reinhard Tartler

apedec: do not buffer decoded samples over AVPackets

Only consume an AVPacket when all the samples have been read.

When the rate of samples output is limited (by the default value
of max_samples), consuming the first packet immediately will cause
timing problems:

- The first packet with PTS 0 will output 4608 samples and be
consumed entirely
- The second packet with PTS 64 will output the remaining samples
(typically, a lot, that's why max_samples exist) until the decoded
samples of the first packet have been exhausted, at which point the
samples of the second packet will be decoded and output when
av_decode_frame is called with the next packet).

That means there's a PTS jump since the first packet is 'decoded'
immediately, which can be seen with avplay or mplayer: the timing
jumps immediately to 6.2s (which is the size of a packet).

Sample: http://streams.videolan.org/issues/6348/Goldwave-MAClib.ape

Bug-Debian: http://bugs.debian.org/744901
Signed-off-by: Justin Ruggles <justin.ruggles at gmail.com>
(cherry picked from commit 91d4cfb8127f1de6c4ad173a30fffe584700046d)
Signed-off-by: Reinhard Tartler <siretart at tauware.de>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=65c3593792a9702d9e4135bba46b1ca186afed6c

 libavcodec/apedec.c |    4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/libavcodec/apedec.c b/libavcodec/apedec.c
index 0abf05b..745b14c 100644
--- a/libavcodec/apedec.c
+++ b/libavcodec/apedec.c
@@ -822,7 +822,6 @@ static int ape_decode_frame(AVCodecContext *avctx, void *data,
     int16_t *samples;
     int i, ret;
     int blockstodecode;
-    int bytes_used = 0;
     /* this should never be negative, but bad things will happen if it is, so
        check it just to make sure. */
@@ -877,7 +876,6 @@ static int ape_decode_frame(AVCodecContext *avctx, void *data,
             return AVERROR_INVALIDDATA;
-        bytes_used = buf_size;
     if (!s->data) {
@@ -920,7 +918,7 @@ static int ape_decode_frame(AVCodecContext *avctx, void *data,
     *got_frame_ptr   = 1;
     *(AVFrame *)data = s->frame;
-    return bytes_used;
+    return (s->samples == 0) ? buf_size : 0;
 static void ape_flush(AVCodecContext *avctx)

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