-vframes option
Output a single frame from the video into an image file:ffmpeg -i input.flv -ss 00:00:14.435 -vframes 1 out.png
This example will seek to the position of 0h:0m:14sec:435msec and output one frame (-vframes 1) from that position into a PNG file.fps video filter
Output one image every second, named out1.png, out2.png, out3.png, etc.ffmpeg -i input.flv -vf fps=1 out%d.png
Output one image every minute, named img001.jpg, img002.jpg, img003.jpg, etc. The %03d dictates that the ordinal number of each output image will be formatted using 3 digits.ffmpeg -i myvideo.avi -vf fps=1/60 img%03d.jpg
Output one image every ten minutes:ffmpeg -i test.flv -vf fps=1/600 thumb%04d.bmp
select video filter
Output one image for every I-frame:ffmpeg -i input.flv -vf "select='eq(pict_type,PICT_TYPE_I)'" -vsync vfr thumb%04d.png
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FFmpeg can capture images from videos that can be used as thumbnails to represent the video. Most common ways of doing that are captured in the FFmpeg Wiki.
But, I don't want to pick random frames at some intervals. I found some options using filters on FFmpeg to capture scene changes:
The filter
thumbnail tries to find the most representative frames in the video:
and the following command selects only frames that have more than 40% of changes compared to previous (and so probably are scene changes) and generates a sequence of 5 PNGs.
Info credit for the above commands to Fabio Sonnati. The second one seemed better as I could get n images and pick the best. I tried it and it generated the same image 5 times.
Some more investigation led me to:
-vsync vfr ensures that you get different images. This still always picks the first frame of the video, in most cases the first frame is credits/logo and not meaningful, so I added a -ss 3 to discard first 3 seconds of the video.
My final command looks like this:
This was the best I could do. I have noticed that since I pick only 5 videos , all of them are mostly from beginning of the video and may miss out on important scenes that occur later in the video
I would like to pick your brains for any other better options.
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