Direct-copy Frame-level MPEG-2 Video Editing

[opieant]

I know that applications such as MPEG-VCR, VideoReDo, and TMPGEnc MPEG Editor exist to do frame-level editing of MPEG-2 PS/TS files by re-encoding only around the cut points. However, I'm considering an alternative method to what these programs use since they're all rather buggy. MPEG-VCR misplaces timestamps, randomly destroys A/V sync, and re-encodes poorly. VideoReDo is somewhat slow and randomly trashes video it's supposed to be copying directly. TMPGEnc sometimes misplaces/miscalculates timestamps, always poorly estimates output file sizes, and sometimes produces files with inconsistent A/V sync).

My idea is to fiddle with the MPEG-2 data so that frame-level editing can be done without re-encoding. The most important thing that would be needed is a way to slightly alter the video data so that the player decodes every picture in the first sequence that it normally would, but only presents pictures starting from the start point selected by the user. At the end of the selection, the sequence could be cut off after all pictures necessary to decode and present the final desired picture have appeared in the data.

So, I'm wondering if anybody here knows if there is a way to selectively disable presentation of pictures (while allowing decoding) using some kind of trickery. It doesn't seem to be a normal capability built into the MPEG-2 spec, but I could certainly be mistaken.

Thanks ahead for any help or info. :)

Greg