Use -qscale:v
to control quality
Use -qscale:v
(or the alias -q:v
) as an output option.
- Normal range for JPEG is 2-31 with 31 being the worst quality.
- The scale is linear with double the qscale being roughly half the bitrate.
- Recommend trying values of 2-5.
- You can use a value of 1 but you must add the
-qmin 1
output option (because the default is-qmin 2
).
To output a series of images:
ffmpeg -i input.mp4 -qscale:v 2 output_%03d.jpg
See the image muxer documentation for more options involving image outputs.
To output a single image at ~60 seconds duration:
ffmpeg -ss 60 -i input.mp4 -qscale:v 4 -frames:v 1 output.jpg
To continuously overwrite/update/save to a single image
Use -update 1
image muxer option. Example for once per second from a live streaming input:
ffmpeg -i rtmp://input.foo -q:v 4 -r 1 -update 1 output.jpg