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--></style></head><body lang=EN-GB link=blue vlink="#954F72"><div class=WordSection1><p class=MsoNormal><b>From: </b><a href="mailto:subrata@ambient.ai">Subrata Goswami</a><br><b>Sent: </b>20 February 2019 22:08<br><b>To: </b><a href="mailto:libav-user@ffmpeg.org">libav-user@ffmpeg.org</a><br><b>Subject: </b>[Libav-user] Strange memory leak and fragmentation</p><p class=MsoNormal><o:p> </o:p></p><div><div><div><p class=MsoNormal>Have couple of simple questions on the following few lines of code. </p><div><p class=MsoNormal><o:p> </o:p></p></div><div><div><p class=MsoNormal><span style='font-family:"Courier New"'> AVFrame *frame = av_frame_alloc();</span></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> AVPacket packet;</span></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> while(av_read_frame(ictx, &packet)>=0) {</span></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> if(packet.stream_index==video_stream) {</span></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> avcodec_send_packet(octx, &packet);</span></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> if(avcodec_receive_frame(octx, frame)==0) {</span></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> }</span></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> }</span></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> }</span></p></div></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>1. The above leaks memory, but the following piece of code does not. </p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><div><p class=MsoNormal><span style='font-family:"Courier New"'> AVFrame *frame = av_frame_alloc();</span></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> AVPacket *packet=av_packet_alloc();</span></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> while(av_read_frame(ictx, packet)>=0) {</span></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> if(packet->stream_index==video_stream) {</span></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> avcodec_send_packet(octx, packet);</span></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> if(avcodec_receive_frame(octx, frame)==0) {</span></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> }</span></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> }</span></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> av_packet_free(&packet);</span></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> packet=av_packet_alloc();</span></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'> }</span></p></div></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>2. Is there any way to reuse the packet structure, else rapid free and alloc probably leads to memory fragmentation. </p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Would appreciate any insight, comment, advice. Thanks . </p></div><div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>You need to use av_packet_unref(&packet); so that the library can free the packet struct after you are done with it. </p><p class=MsoNormal>https://ffmpeg.org/doxygen/4.0/group__lavc__packet.html#ga63d5a489b419bd5d45cfd09091cbcbc2</p></div></div></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>