MAMEWorld Forums - The Loony Bin - Re: Free tool to split MP4 files

> > I'm going to have to check it out.
> >
> > The tool that I used has a weird side effect when splitting files. Sometimes, the
> > first few seconds of the split file has crazy colors like the palette is messed up
> or
> > something. I'm not sure what, exactly, is happening.
>
> There are certain frames where the whole picture is stored - called keyframes. The
> rest of the frames only store difference between the previous and the current frame.
> When you split a stream between two keyframes, the first frame is missing the
> previous frame to render correctly, thus the weird colours and stuff until the stream
> finds its first keyframe which renders correctly.
>
> Usually video editing programs have means to move between keyframes, or at least show
> that you're at one, so you can ensure that the first frame of your splitted vid is a
> keyframe.

If you are cutting the video between keyframes, it should be a fairly simple matter to roll back to the last keyframe and then construct a new keyframe (based on the data in all subsequent frames) and insert it into the current position - making the split frame a new key frame. It would mean that 2 keyframes are closer than normal together, but it should still play fine - and no ugly mess.

Moose