user11310: According to https://github.com/mpv-player/mpv/issues/4019 backward stepping for example with H264 codec is slow compared to forward stepping. Other codecs, for example mjpeg works a bit better.
For which other codecs/codec settings backward stepping is fast?

user3908: As @Mulvya says it depends greatly on the GOP size, but you can insure that stepping is easy at the expense of file size, by using an 'all-I' codec like Motion JPEG. In such codecs every frame appears whole and entire so there is no dependence on previous or subsequent frames.

11310: <p>According to <a href="https://github.com/mpv-player/mpv/issues/4019" rel="nofollow noreferrer">https://github.com/mpv-player/mpv/issues/4019</a> backward stepping for example with H264 codec is slow compared to forward stepping. Other codecs, for example mjpeg works a bit better.</p>

<p>For which other codecs/codec settings backward stepping is fast?</p>
 3908: <p>As @Mulvya says it depends greatly on the GOP size, but you can insure that stepping is easy at the expense of file size, by using an '<strong>all-I</strong>' codec like Motion JPEG. In such codecs every frame appears whole and entire so there is no dependence on previous or subsequent frames.</p>
