Screenshots with Core Media Player/Ffdshow

[Starman*]

I've started to use the Core player/ffdshow for mkv videos. It works fine for general playback. I want to capture screenshots which I've set up in ffdshow in the "Grab" section. That works if I press the "Grab now" button. I cannot get it to work with the hotkey that I activated in the "Keys.." section. That's G, presumably with some combo of Ctrl and Alt. G is not used in the Core player hotkeys so there is no apparent conflict there.

In addition to the above problem, is there a guide to ffdshow anywhere? Many of the parameters have descriptions that are quite meaningless unless you wrote the software.

[Starman*]

I found one other query on the Net similar to my problem but with no resolution other than unhelpful suggestions to try something else. I may have resolved my problems by trial and error. My comments below are supposition as to what cured the problem, not fact.

1. I had installed ffdshow on 2 pcs by different means, Sourceforge and CCCP codec. They seem to have installed it in different places on the pcs with differing behaviours. The Sourceforge install came with Help files.

2. The CCCP codec install seemed to link mkv files with ffdshow so that Core Media Player used ffdshow when it ran them. Perhaps that could be done with appropriate settings not using CCCP. I then used CCCP on both pcs.

3. I added ffdshow video decoder in CMP / Preferences / Directshow Summoner. I don't know whether this made a difference.

4. Once the hot key Ctrl+Alt+G was working I found it only (apparently) worked if the video was running. If you tried it on a freeze-frame, nothing seemed to happen. However as soon as you restarted the video, the capture appeared. If you hit capture say 5 times on the freeze-frame, it would capture the current and next 4 frames when the video restarted.

I'm still experimenting with the cumbersome capture and shuttle controls. There do not seem to be any players that can reliably shuttle a single frame forward and backward with mkv files (or avi for that matter). With the video I'm using, CMP will only increment 4 frames at a time in either direction, and that requires 4 arrow key presses.