-
i-frame recognition
I need a CLI application that will analyze a video file and output the i-frame location as timecode or framenumber in text. I know its a long shot for ffmpeg to do something like this as ffmpeg is not made to analyze video, but its worth asking. Any suggestions?
Doug
-
3 Replies
-
[Doug Bay] “I know its a long shot for ffmpeg to do something like this”
Not at all!
FFprobe (which installs with newer FFmpeg builds) is your candidate.
$ ffprobe -show_frames input.mp4
This will print out various attributes for each frame.
What you are after is “coded_picture_number=” for the frame and “pict_type=” for frame type (I,P or B).I usually use grep to turn this into useful data without all of the other noise.
For your requirements:
$ ffprobe -show_frames input.mp4 2> /dev/null | grep ‘coded_picture_number|pict_type’It is important to note that the “coded_picture_number” starts logically at 0 so you may need to offset this by 1 depending on how you use the output.
Michael
-
I just realised my escape slash was removed by the text editor as an escape slash;-(
this:… grep ‘coded_picture_number|pict_type’
should read
grep ‘coded_picture_number\|pict_type’
Michael
-
There is also a filter that will give frame info.
ffplay input.mp4 -vf showinfo |& grep 'type:I'
Reply to this Discussion! Login or Sign Up