avisynth generate wrong audio pts

[chinshou]

I just found avisynth.c generate very large audio pts.

we can use ffplay to play following avs

a0=DirectShowSource?("1.avi")
v1=ImageSource?("1.jpg", start=0, end = 14900, fps=30).BilinearResize?(320,240)
video=FlipVertical?(v1)
audio=(a0)
AudioDubEx?(video,audio)

From the ffplay console log

18178.97 A-V:18166.132 s:0.0 aq= 314KB vq= 8552KB sq= 0B f=0/0 /0

I noticed that audio pts was very large than video pts.It seems we should remove following code from avisynth_read_packet function

pkt->pts = stream->read;<-------------remove this line

and correct pts should be

pkt->pts = avs->streams[stream_id].read / avs->streams[stream_id].chunck_samples;

static int avisynth_read_packet(AVFormatContext *s, AVPacket *pkt)
{
...

if (av_new_packet(pkt, stream->chunck_size))

return AVERROR(EIO);

pkt->stream_index = stream_id;
pkt->pts = avs->streams[stream_id].read / avs->streams[stream_id].chunck_samples;

res = AVIStreamRead(stream->handle, stream->read, stream->chunck_samples, pkt->data, stream->chunck_size, &read_size, NULL);

pkt->pts = stream->read;<-------------remove this line
pkt->size = read_size;

stream->read += stream->chunck_samples;

...
}

best regards
chinshou

[cehoyos]

Please produce your patch with "git diff libavformat/avisynth.c >patchavisynth.diff" and send the resulting file patchavisynth.diff to ffmpeg-devel (or attach it here).

[chinshou]

I have upload the patch, besides pts bug fix, this patch also fix the image displayed upside down bug .The upsidedown bug can be reproduced by following avs script

ImageSource?("Sample1.jpg", start=0, end = 40, fps=25)

[cehoyos]

The indentation looks wrong, if the setting of pts is really wrong (I don't know, but in your original report you suggest an alternative calculation), please remove the line (do not just outcomment it), and unfortunately, we absolutely require "one patch per issue", so please attach (or send to ffmpeg-devel) one patch for the original (pts) issue and one patch for upside-down.

[chinshou]

Replying to cehoyos:

The indentation looks wrong, if the setting of pts is really wrong (I don't know, but in your original report you suggest an alternative calculation), please remove the line (do not just outcomment it), and unfortunately, we absolutely require "one patch per issue", so please attach (or send to ffmpeg-devel) one patch for the original (pts) issue and one patch for upside-down.

I have split the fix to two patches, original avisynth calculate the pts two times, the finally calculation was wrong , so I only delete one line in the pts patch.

[michael]

Both patches applied
Thanks