Seeing I Frames with Sony Vegas Platinum?

[HoosierGuy]

I'm reading a new book I recently bought - How Video Works. I really needed a primer on the basics of video and this book is a decent primer.

Anyway, yesterday I read about Mpeg compression and how I frames and P and B frames work. I can't say I completely understand the process but now know about
this.

Is there any way in Sony Vegas Studio to find these I frames and P and B frames? Can these P and B frames even be shown in editing programs?

Thanks

[jagabo]

VirtualDub and VirtualDubMod will show you whether each frame is an I, B, or P frame (in the status bar at the bottom of the window, where it shows the frame number, etc.). Any MPEG decoder knows what type of frame each frame is or else it wouldn't be able to decompress the video. But that information may not be passed to the editor itself, and even if it is, the editor may not present that information to the user.

[HoosierGuy]

Thanks. I don't really have a need to see the information. I just read about it in a book and was wondering if it's important to see and know about when editing in programs like my Sony Vegas Studio.

[jagabo]

About the only time you really need to know the frame type, is when working with non-reencoding editors that only allow cuts on I frames -- Mpeg2Cut2 for example. They will usually only show you the I frames anyway. "Smart" editors will only reencode cut GOPs. Dumb editors will reencode the entire video if you make any changes, even removing one frame from the very end.

You may need to verify the GOP size on occasion. For example, DVD players have limits on the number of frames in a GOP. GSpot can show you the max GOP length.