Editing compressed H.264 video

[photoguy123]

Hi all,

Is this possible in AVISynth? (or any tool you know)

1) To join together clips of h.264 compressed video without decompressing?

2) To replace the aac audio track in a container with h.264 video, without decompressing anything?

It seems (1) is theoretically possible based on research I've googled, but I'm trying to find out if it's just theoretically possible, or if there is a real way to do it.

Thanks for any feedback, LTG

[Blue_MiSfit]

Avisynth doesn't operate directly on compressed video.

What you need is a tool that can handle advanced muxing operations.

Now as to your specific questions:
1) Joining clips requires that both clips be VERY similar. I.E. same resolution, settings etc... Bitrate need not be the same IIRC. I've never done this, but it should be possible.

2) This should be very easy to do with MKVToolnix (if you're using the MKV container) or YAMB if you're using the MP4 container.

~MiSfit

[photoguy123]

Thanks Blue.

That gives me a couple places to start.

Regards,
LTG

[Sagekilla]

Well, for #2 if you're using mkv files you can use mkvtoolnix to simply open up the container and remux the file (as a new file) with the new audio track. If it's a .mp4 file, YAMB will do fine for this as well. Otherwise if it's an avi you can use VirtualDubMod.

[photoguy123]

Thanks Sage, I wish I were using mkv but since I need iPhone support i'm forced to use mp4.

But from my reading so far it looks like YAMB/Mp4box is able to do both (1) and (2) with h.264.

where would the world be without open source? :)

[Sagekilla]

Thanks Sage, I wish I were using mkv but since I need iPhone support i'm forced to use mp4.

But from my reading so far it looks like YAMB/Mp4box is able to do both (1) and (2) with h.264.

where would the world be without open source? :)

Probably stuck using WMV..