Suggestion: IDR frames

Begonnen von sillyphilly, Mai 06, 2018, 19:50:21

« vorheriges - nächstes »

sillyphilly

What would be usefull is the ability to cut in at IDR frames. Seeing what frames are IDR frames in the cutting window would be nice as well. ffprobe has the ability to display IDR(key_frame=1) so I would assume it wouldn't be too hard for an editor that scans packets.

Mam

actually, what you ask for already exists  8)

look at the screenshot, the two buttons make the program search for the next/last IDR Frame. the little "I" in the marked box signals that you are just now "standing" on an I Frame.
In the options you can select if you want the cutting point automatically adjusted ahead or behind the current I Frame.


sillyphilly

#2
That's not neccessarily IDR frames. If you cut at an I-frame and you get pixelation in the output video then the frame was probably not an IDR frame. TV transmissions in some countries don't even use them, using SEI recovery points to facilitate random access. In the MPEG-2 SD world you would close the GOP at cut-in but you don't do that for h264, rather you cut-in at IDR frames or re-encode the video if it referes to before the cut-in.

Edit: Indexing your files in DGIndexNV will yield the frame-type of each frames. In the resulting .dgi gile it tells you the byte offset(I think) of IDR frames amongst others. The file is sorted by frame number so it's quite easy to see which I-frames are IDR frames.


www.cypheros.de