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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>To obtain the fps for a video stream, I’ve been using the following code:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>if (pFormatCtx->streams[videoStream]->avg_frame_rate.num == 0)<o:p></o:p></p><p class=MsoNormal style='text-indent:.5in'>*frameRate = (float)av_q2d(pFormatCtx->streams[videoStream]->r_frame_rate);<o:p></o:p></p><p class=MsoNormal>else<o:p></o:p></p><p class=MsoNormal> *frameRate = (float)av_q2d(pFormatCtx->streams[videoStream]->avg_frame_rate);<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>And then while reading the video, to determine the PTS for a frame, the following code:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>if (decoder_reorder_pts == -1) {<o:p></o:p></p><p class=MsoNormal> *pts = av_frame_get_best_effort_timestamp(pFrame);<o:p></o:p></p><p class=MsoNormal>} else if (decoder_reorder_pts) {<o:p></o:p></p><p class=MsoNormal> *pts = pFrame->pkt_pts;<o:p></o:p></p><p class=MsoNormal>} else {<o:p></o:p></p><p class=MsoNormal> *pts = pFrame->pkt_dts;<o:p></o:p></p><p class=MsoNormal>}<o:p></o:p></p><p class=MsoNormal>if (*pts == AV_NOPTS_VALUE) {<o:p></o:p></p><p class=MsoNormal> *pts = 0;<o:p></o:p></p><p class=MsoNormal>}<o:p></o:p></p><p class=MsoNormal>*pts *= av_q2d(pFormatCtx->streams[videoStream]->time_base);<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>And this has worked fine with every video format that I analyze, except for asf files as recorded by Axis cameras, which have the wrong values for the frame rate, spec.,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>pFormatCtx->streams[videoStream]->r_frame_rate = 100<o:p></o:p></p><p class=MsoNormal>pFormatCtx->streams[videoStream]->avg_frame_rate = 0<o:p></o:p></p><p class=MsoNormal>pFormatCtx->streams[videoStream]->time_base = 1 / 1000 <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>whereas the file is actually recorded at 30 fps. <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>ffprobe also reports invalid values:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>r_frame_rate=100/1<o:p></o:p></p><p class=MsoNormal>avg_frame_rate=0/0<o:p></o:p></p><p class=MsoNormal>time_base=1/1000<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The “Windows Media ASF View 9 Series” tool reports the correct information as follows (in Extended Stream Properties):<o:p></o:p></p><p class=MsoNormal>Avg. Time / Frame 00:00.0333333<o:p></o:p></p><p class=MsoNormal>Avg. Frames / Second 30.00<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>VLC Media Player, Windows Media Player and ffplay play these asf files just fine; and yet, using the above code results in incorrect value for the time base used to determine the PTS of each frame. How can I get the correct values from the asf files using ffmpeg funtions?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal> Ron<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>