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A few more data points:<o:p> </o:p></p>
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The issue is in the AAC stream. On the first file create by my program the PTS in the packets written with av_write_frame() are the same as what is in the container file (as per ffprobe) but in subsequent files a seeming random value (same value for the whole
file) is add to each PTS that is passed to av_write_frame() for that file.<o:p> </o:p></p>
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I hope this will make it clear to someone what I am doing wrong.<o:p> </o:p></p>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> william keeling<br>
<b>Sent:</b> Saturday, May 8, 2021 1:32 PM<br>
<b>To:</b> libav-user@ffmpeg.org <libav-user@ffmpeg.org><br>
<b>Subject:</b> Start time and duration questions</font>
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I have a program that iterative creates Flash container files with 2 streams (video h264 and audio AAC).<span style="">
</span>The format and codec contexts are allocated before and freed after each file.
<span style=""> </span>Calls are made to avformat_write_header() after contexts are allocated and to av_write_trailer() before contexts are freed.<span style="">
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I am using 1 for AVFormatContext.start_time_realtime (since 0 will get current system time).
<span style=""> </span>How do you start from 0 when muxing? </p>
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The other issue is first file shows the correct start time and duration when played thru VLC media player.<span style="">
</span>All subsequent files show a 0 start time, large duration and a black screen for a while; then the start time changes to a large start time that is correct run time below the duration and the video plays.
<span style=""> Any </span>ideas what I have done wrong that is causing the wrong start and duration time and the delay in video playing but only on subsequent files? </p>
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Thanks </p>
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