-----Original Message Starts----- From: [email protected] [mailto:[email protected]] On Behalf Of Prageeth Sent: Wednesday, September 29, 2010 5:58 PM To: [email protected] Subject: [libav-user] Help with av_find_stream_info()
Hi All, I am using the ffmpeg libraries to demux the audio/video streams from a DTV TS stream. I pipe the TS packets obtained from hardware to the program, call av_find_stream_info() and later check codec_type of the stream to find audio/video streams. The method works and I am able to later decode the frames thus obtained. The issue I face is that a lot of time is spent inside av_find_stream_info(), more than 1minute, as in attached logs. The call seems to need much TS data to complete processing. With some debugging, it was found that av_read_packet () inside av_read_frame_internal() does most of processing. Can somebody suggest possible solutions? Is it somehow possible to optimize av_find_stream_info() for my scenario? Any help appreciated. Thanks & Regards, Prageeth [Wed Sep 29 16:46:53.062 2010]demux:av_find_input_format start [Wed Sep 29 16:46:53.062 2010]demux:av_find_input_format end [Wed Sep 29 16:46:53.062 2010]demux:av_open_input_file start [Wed Sep 29 16:47:23.203 2010]raw_packet_buffer_remaining_size=2500000 [Wed Sep 29 16:47:23.234 2010]demux:av_open_input_file end [Wed Sep 29 16:47:23.234 2010]demux:av_find_stream_info start [Wed Sep 29 16:48:04.796 2010][aac @ 0x9b9d00]channel element 3.3 is not allocated [Wed Sep 29 16:48:34.953 2010][NULL @ 0x9bb390]non-existing PPS referenced [Wed Sep 29 16:48:34.953 2010][h264 @ 0x9bb390]non-existing PPS 1 referenced [Wed Sep 29 16:48:34.953 2010][h264 @ 0x9bb390]decode_slice_header error [Wed Sep 29 16:48:34.953 2010][h264 @ 0x9bb390]no frame! [Wed Sep 29 16:48:34.953 2010][h264 @ 0x9bb390]non-existing PPS referenced [Wed Sep 29 16:48:34.953 2010][h264 @ 0x9bb390]non-existing PPS 1 referenced [Wed Sep 29 16:48:34.953 2010][h264 @ 0x9bb390]decode_slice_header error [Wed Sep 29 16:48:34.953 2010][h264 @ 0x9bb390]no frame! <snipped similar messages> [Wed Sep 29 16:48:35.312 2010] max_analyze_duration reached [Wed Sep 29 16:48:35.312 2010] [mpegts @ 0x9ae140]Estimating duration from bitrate, this may be inaccu [Wed Sep 29 16:48:35.312 2010] demux:av_find_stream_info end [Wed Sep 29 16:48:35.312 2010] Input #0, mpegts, from '(null)': [Wed Sep 29 16:48:35.312 2010] Duration: N/A, start: 21621.585433, bitrate: 50 kb/s <snipped> [Wed Sep 29 16:48:35.328 2010] No Program [Wed Sep 29 16:48:35.328 2010] Stream #0.0[0x883]: Audio: aac, 48000 Hz, mono, s16, 50 kb/s [Wed Sep 29 16:48:35.328 2010] Stream #0.1[0x887]: Data: 0x0000 [Wed Sep 29 16:48:35.328 2010] Stream #0.2[0x881]: Video: h264, yuv420p, 320x180, 11.44 fps, 14.99 [Wed Sep 29 16:48:35.328 2010] tbr, 90k tbn, 14.99 tbc -----Original Message Ends----- Hi All, On further debugging, it looks like probing for AAC consumes most time/data. Any suggestions on how to speed this up? Thanks & Regards, Prageeth _______________________________________________ libav-user mailing list [email protected] https://lists.mplayerhq.hu/mailman/listinfo/libav-user
