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<p>I had the same problem as you, but this worked for me: "<span style="color: rgb(33, 33, 33); font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 16px; background-color: rgb(255, 255, 255);">I tried sending a NULL packet and using avocdec_flush_buffers()
to flush out the decoded frame</span>"<br>
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<p>Even though it was functionally correct, that approach was too slow. If I remember correctly that was due to (re)initialization time for the decoder.<br>
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<p>However, I ended up moving all the decode to NVDEC directly anyway.<br>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> Libav-user <libav-user-bounces@ffmpeg.org> on behalf of rohit khali <khali.rohit@gmail.com><br>
<b>Sent:</b> Friday, November 6, 2020 12:43 AM<br>
<b>To:</b> This list is about using libavcodec, libavformat, libavutil, libavdevice and libavfilter.<br>
<b>Subject:</b> [EXTERNAL] [Libav-user] FFMPEG to decode I frames</font>
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<div dir="ltr">Hi,<br>
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<div>My application parses only I frames from H264 bit stream and hands it over to FFMPEG decoder.</div>
<div>Expectation was that FFMPEG decoder immediately output decoded frames since input is I frame. However, FFMPEG can't do this especially for cases where I frame is not an IDR.</div>
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<div>I tried sending a NULL packet and using avocdec_flush_buffers() to flush out the decoded frame but this logic doesn't seem to work for all cases, maybe again depending on DPB size or POC.</div>
<div>I was wondering if anyone else has used FFMPEG for such a use case earlier and what else I can use to immediately receive the I frames.</div>
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<div>Thanks,</div>
<div>Rohit Khali</div>
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