[FFmpeg-user] Pull out 10 frames, one frame at a time for 10% of the video

[Варзанов Дмитрий]

Hello. My team

ffmpeg -i FILE -c:v libwebp -lavfi '[0:v]fps=1/".(300/10).",split=2[v0][v1];[v0]scale=1056:594,boxblur=luma_radius=min(h\,w)/20:luma_power=1:chroma_radius=min(cw\,ch)/20:chroma_power=1[bg];[v1]scale=-1:594[pic];[bg][pic]overlay=(W-w)/2:(H-h)/2' -vsync vfr -start_number 0 img%d.webp) > /dev/null 2>&1

The whole team is what it is, I have one simple but very important question for me.

The video duration is 300 seconds to pull 10 frames every 10% of the video duration. It is necessary to know in advance the duration that needs to be divided and get the time interval after which we pull out the frame.

fps=1/".(300/10)."

Is it possible to take a frame every 10% without setting the duration in advance?.. At the output, get 10 frames and do not execute the command in advance to get this very duration.

It turns out to be expensive, you first need to find out the duration of the video, only after that it is possible to pull out 10 frames, every 10%

I would really like to exclude 1 command, obviously not execute the command to find out the duration in seconds.