Cutting bytes of a .avi video file

driesguldolf · Post by **driesguldolf** » Mon 10 Sep, 2007 9:05 pm

Does anyone know a way to cut unwanted bytes of a video file? (Cutting out some video to make the file smaller?)

I have some vids but they're just over 700Mb wich means I can't get em on a CD

Post by **tr1p1ea** » Mon 10 Sep, 2007 9:15 pm

Download virtualdub from www.virtualdub.org

Open the file, move the slider to the start of the part you dont want, press HOME, move it to the end of the part you dont want, press END, then press DEL to remove the selection. Ensure that the video/audio is set to direct stream copy, file save as.

Post by **benryves** » Tue 11 Sep, 2007 11:33 am

I assumed that the question was more related to recompression, which VirtualDub can also do (set the compression parameters from the Video and Audio menus).

If I want to shrink a video to a particular size, I've found Movie Maker to be very useful (if you don't mind WMV).

Lossily recompressing an already lossily compressed source tends to look horrible, though.

Post by **tr1p1ea** » Tue 11 Sep, 2007 11:59 am

Well he did say 'cutting out' ... but yes, set video/audio to full processing mode, select your compression settings and wait an hour or so

.

Homestar · Post by **Homestar** » Wed 12 Sep, 2007 3:03 pm

Have you thought of putting it on a DVD?

Just changing the format will help you greatly, as .avi is one of the larger size files (as it has some more flexibility for video edititn). However, I think you're finished with the project and need to RENDER/Convert rather than "compress" per-se.

When you think of compression it tends to have the idea of lessening the quality to get a smaller file size, and even though rendering doesn't mean anything different (per-se) than compressing, it tends to not be associated with the loss of quality.

When I edit video, I normally leave it as .avi, as it holds the most quality, but stepping it down to .wmv, gives almost an un-noticable loss in quality* with about 3/4 of the memory
*depending on your settings

If you want to cut in in half, try rendering into MP4. This will lower the quality noticeably, but not as much as most web videos like YouTube.

Post by **benryves** » Wed 12 Sep, 2007 3:23 pm

Homestar wrote:Just changing the format will help you greatly, as .avi is one of the larger size files (as it has some more flexibility for video edititn).

AVI is just a container format. You can store MPEG-4 video and MP3 audio inside it quite merrily (much like WAV is a sort container based on RIFF, and can be uncompressed PCM or compressed MP3 data inside). You can store WMV compressed video inside an AVI (though, typically, you use ASF as the container).

Homestar · Post by **Homestar** » Wed 12 Sep, 2007 4:02 pm

yes, once just to experiment I rendered from .mp4 into .avi and the file size did grow. Nothing major, but noticeable, my main point is that most formats are smaller that .avi.

King Harold · Post by **King Harold** » Wed 12 Sep, 2007 4:26 pm

Is that not just because of the extra AVI header?
Seems to me that it won't really matter..

Post by **tr1p1ea** » Wed 12 Sep, 2007 5:31 pm

Homestar, like ben said, avi is not a 'format' its a container. You could recompress the audio/video inside it to a different format that would see a reduction.

driesguldolf · Post by **driesguldolf** » Wed 12 Sep, 2007 6:20 pm

Thanks for your comments, I'll try the link you gave me tr1p1ea and convert between some formats to see wich is most optimal to use.

Jim e · Post by **Jim e** » Wed 12 Sep, 2007 7:54 pm

No, Homestar is right. AVI is a very HACKED container, So codecs need to add a lot of crap to it to get stuff right. Matroska or Ogm might save on size, but only a small bit.

If you are only talking about KB, clipping the last few frames out would do it.

If it's only a couple MB, you could re-compress the audio to better a compression. Long videos with MP3 can be greatly reduced in size by switching to vorbis at a lower bitrate.

If it's several MB, the video would need to be re-compressed. Using H.264 codec would cut the size down greatly with out to much quality loss, though it takes a very long time to do.

driesguldolf · Post by **driesguldolf** » Wed 12 Sep, 2007 10:16 pm

I can cut over 2/28 of every movie (the credits), wich is about 50Mb.

And yeah, Homestar, the problem is that I have free CDs here (the ones my father bought

) and not much DVDs (which I bought myself)
Anyway a vid takes 2.5 Gb so I won't have much choice (And I really don't want to reduce the awesome quality

)

I'll try your suggestions Jim e

Post by **tr1p1ea** » Thu 13 Sep, 2007 7:54 am

Regardless of whether or not AVI's need extra codec info, implying that they are a video format is wrong.

And please dont talk about ripping specific DVD's on these boards (dont name them!).

Jim e · Post by **Jim e** » Thu 13 Sep, 2007 12:23 pm

tr1p1ea wrote:Regardless of whether or not AVI's need extra codec info, implying that they are a video format is wrong.

And please dont talk about ripping specific DVD's on these boards (dont name them!).

It is a format, that term is perfectly fine. However format is a very generic word, so most people use container. Even if the reason he was right was wrong, he's still right.

driesguldolf · Post by **driesguldolf** » Thu 13 Sep, 2007 12:26 pm

ah yeah, most of the vids (with .avi) extension are xvid/divx (whats the difference anyway) coded, of which is said that they're one of the best formats... I could have missed the point entirely though