is it possible to convert a video to set of images *while keeping them in high quality*?
I am currently using
ffmpeg for this but the quality of the images seem to be quite bad
You mean programatically? After Effects / Premiere can do this.
However, ffmpeg should be fine.
What are your settings? You can set the output quality with
-qscale:v 2 The range you can set is 2-31 I think while 31 is the worst quality.
There are also a lot of plugins for ffmpeg so you can output tiffs, of jpegls for lossless jpgs