I want to extract the video frames and get the PTS timestamp for each one of them. I have an input MPEG-2 TS file and I prefer to use some open source tool like ffmpeg or something similar. The problem is that when I am using -vf showinfo option it shows me a restamped PTS. This is the command I am using:

ffmpeg -hide_banner -i input.ts -vf showinfo -vsync 0 -start_number 0 fr%05d.jpg &> log.txt

So here my result is something similar to:

[Parsed_showinfo_0 @ 0x5629810a2000] n: 435 pts:1593000 pts_time:17.7    pos: 55729780 fmt:yuv420p sar:1/1 s:1920x1080 i:T iskey:0 type:B checksum:27AB3255 plane_checksum:[B27F2CE8 F1689963 59E56BFB] mean:[142 127 129] stdev:[36.5 2.8 4.1]
[Parsed_showinfo_0 @ 0x5629810a2000] n: 436 pts:1596600 pts_time:17.74   pos: 55690112 fmt:yuv420p sar:1/1 s:1920x1080 i:T iskey:0 type:B checksum:94AD9CBE plane_checksum:[FB0C9721 C477122C 2AA6F362] mean:[142 127 129] stdev:[36.5 2.8 4.1]

While when I execute the ffprobe command:

$ ffprobe -i input.ts -show_frames -select_streams v:0 -print_format flat | grep pkt_pts=

frames.frame.435.pkt_pts=4205067450
frames.frame.436.pkt_pts=4205071050

And I need to find out the pkt_pts timestamp on the extracted files possibly with only one command. On top of that, I was checking the SCTE-35 and there I had an offset with 150 frames between the insert intervals. For example according to the PKT_PTS the start and stop frames are 1650 and 2550 which are signaled over SCTE-35 but the actual frames are 1500 2400 when I look only on the extracted frames.

up vote 1 down vote accepted

FFmpeg will, by default, remove the starting offset. To preserve it, add -copyts.

The description of -vsync 0 isn't accurate and was written 8+ years ago: Each frame is passed with its timestamp from the demuxer to the muxer.. Video sync takes effect only once the frame has exited the decoder(+filtergraph) pipeline. But you should keep it to avoid dropping/duplicating frames.

  • yes, this works great, thanks for the hint! I just didn't understand whether I should use -vsync 0 or not in my command line. – Georgе Stoyanov Nov 8 at 18:32

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