Currently I am using this command to extract the images:
ffmpeg -i input.mp4 output_%03d.jpeg
But how can I improve the JPEG image quality?
This question is related to
video
ffmpeg
graphics
computer-vision
Output the images in a lossless format such as PNG:
ffmpeg.exe -i 10fps.h264 -r 10 -f image2 10fps.h264_%03d.png
Edit/Update: Not quite sure why I originally gave a strange filename example (with a possibly made-up extension).
I have since found that
-vsync 0
is simpler than-r 10
because it avoids needing to know the frame rate.This is something like what I currently use:
mkdir stills ffmpeg -i my-film.mp4 -vsync 0 -f image2 stills/my-film-%06d.png
To extract only the key frames (which are likely to be of higher quality post-edit):
ffmpeg -skip_frame nokey -i my-film.mp4 -vsync 0 -f image2 stills/my-film-%06d.png
Then use another program (where you can more precisely specify quality, subsampling and DCT method – e.g. GIMP) to convert the PNGs you want to JPEG.
It is possible to obtain slightly sharper images in JPEG format this way than is possible with -qmin 1 -q:v 1
and outputting as JPEG directly from ffmpeg
.
Source: Stackoverflow.com