MPC-HC: Play at Exact Frame

[Jay123210599]

MPC-HC keeps going at keyframes even though fast seek is unchecked. What should I do to fix that?

[butterw]

re:"MPC-HC: Play at Exact Frame"
not a feature of directshow players.

MPC-HC is a direstshow based player. Seeking in directshow players is not guaranteed to be frame accurate. In practice seeking to a frame time is frame accurate for keyframes though.

[hello_hello]

I don't know why it's ignoring the fast seek setting, but if you know the number of the frame you're after, you should be able to navigate directly to it using the Navigate/GoTo menu.

Maybe disabling fast seeking is a little dependent on whether hardware decoding is used. I don't actually know, but I have MPC-HC running in Wine on Linux (just for fun) and enabling/disabling fast seeking works as expected. I tested it on AVC and HEVC video, both in an MKV container. In my case there's no hardware decoding or DirectShow involved.

[butterw]

Seeking is done using time internally. Using a frame number in the "Go to" entry is not more accurate than using a ms precision timestamp. This was confirmed by mpc-be dev.

[ChristianundCo]

Without avisynth script and frame indexing - no way!

[hello_hello]

Seeking is done using time internally. Using a frame number in the "Go to" entry is not more accurate than using a ms precision timestamp. This was confirmed by mpc-be dev.

All seeking is done by time as there's no such thing as frame numbers, only timestamps, at least as far as I know. Timecodes for the MKV container are generally rounded to whole milliseconds.

I can only relate my experience using MPC-HC with MKV sources and scripts, as it's what I mainly work with, but I've used the GoTo menu countless times to compare a frame in the original video with the output of an Avisynth script and found it to be fairly accurate. It's invariable off by a frame compared to Avisynth when opening a script, as Avisynth starts counting at zero, but other than that it always manages to land on the correct frame.

Admittedly when navigating towards the end of a long video it can sometimes be off by a frame, but only when opening a source file and not a script. I don't know why. At least entering the same frame number should return you to the same frame every time though.
Maybe being off by a frame towards the end of a long video has something to do with the frame the decoder decides to return, given it doesn't happen when viewing scripts. I'm not really sure. For the purpose of viewing a specific frame though, if it's simply a matter of adjusting the frame number by one, it does the job. It's definitely more accurate than trying to seek to a specific frame by clicking on the navigation bar.

Close to the beginning of a video. Script on top, source file on the bottom.



More than two hours into the video. Script on top, source file on bottom. Off by one frame for the source video, keeping in mind the MPC-HC and Avisynth frame numbers are always off by one due to Avisynth counting from zero.

[butterw]

All seeking is done by time as there's no such thing as frame numbers, only timestamps, at least as far as I know. Timecodes for the MKV container are generally rounded to whole milliseconds.

That's my understanding. The time for a given frame number is just estimated using the frame-rate.

And seeking with mpc-hc does typically work well, but you could still be off by a frame, maybe more in some cases and this isn't a bug. My advice with mpc-hc on windows would be to stick to keyframes when exact frames are required.