How might I shrink mpg video files to save space?

[Florestan]

I have a rather large video collection and it takes up a TON of space. All the files are MPG and were transcoded as either MPEG TS or MPEG PS using the mp4v codec for video at 1024 kb/s and mpega for audio at 192 kb/s. I would like to save these video files as some other type of video file so that they take up less space, but I don't want noticeable compression - I tried transcoding them as mp4v and mp4a in an mp4 container, but the video appeared blocky, sort of like dithering in GIF images or TV image censoring, if that helps explain it. I know MPEG isn't the best choice here, though. I don't know much about the different types of files or containers or transcoding options available or how to use them.

Could someone suggest a way to shrink these files without noticeable loss of video/audio quality, and tell me how to do it?

[DJ]

MP4v should not be placed in a MPEG PS or TS container. Are you sure this is the format they are in?

Could someone suggest a way to shrink these files without noticeable loss of video/audio quality, and tell me how to do it?

This is the desire of most everyone. To be able to display a file that takes up very little space and have it playable on any size monitor without any artifacts. Lets make it stream-able too on any High speed network or modem over the Internet.

H.264 is the most likely to fill this bill, but it is one of the most difficult encoders to learn and there is not real good cross compatibility, it is not native to anything and the encoding times are twice as long as anything else.

[Florestan]

Oops. I read the default codec in the streaming menu instead of the one I actually used. I ctrl-i'd and it's with mpgv and a52 audio, but the bitrates are correct and the container is too. Sorry.

I realize everyone wants the perfect video format, but I'm just trying to find anything that's better than mpg, seeing as that's one of the largest types. I'm actually not concerned at all with cross-compatibility or streaming options, and it can be compressed some, I just don't want it compressed to YouTube proportions or it defeats the whole purpose of storing my videos myself. I'm willing to take on learning a difficult encoding procedure; I've been trying to learn more about VLC and how video files work. If H.264 is the best option, I'll go for it - can you suggest how I'd start learning this? Again, anything will do as long as it's at all better than mpg, so if there are other options, I'd be interested in them also.

Thanks for your reply.

[joseph5]

If H.264 is the best option, I'll go for it - can you suggest how I'd start learning this?

Try:
http://www.doom9.org
http://www.digital-digest.com
http://www.videohelp.com
There are many tutorials on those websites.

[Florestan]

Thanks joseph5! I've been looking, and it seems that while you use an asf container and h264 for video, there are various transcoding options for the audio. Is there any that anyone would recommend as best for this container? I ended up just playing with VLC for awhile until I got it to work, but there could be a better way.

Thanks for all the help. I know I'm asking for a bit of an ideal here.

[DJ]

Use the MP4 container and AAC (MP4a) for audio. This can be made to be QT compatible.

[Florestan]

Hmm... when using an asf container and asf encapsulation, it worked, but when you drag the marker around to move to a different part of the movie, it would invert the colors and go all blocky for just a sec - not that the video itself was corrupted, it just messed up a little bit right when you drag it.

Use the MP4 container and AAC (MP4a) for audio. This can be made to be QT compatible.

I tried the AAC audio with the MP4 container and it simply does not work. It seems like it's working when I pause it in the middle of saving and test the file, but if I let it do the entire file it stops right at the end, freezes, and then the file is unreadable by VLC (and QT). What encapsulation method is used for this? MP4 is what I did. Am I doing something wrong? I've been reading about this codec for the past couple days now and I haven't seen anything addressing this issue.

[DJ]

Sorry, I haven't experienced this issue. This is a standard combination and has always worked for me. Another standard combination is h.264 with ac3 (A/52) in a AVI container or in a Matroska (MKV) container. Unfortunately, VLC does not support these containers for transcoding.

[Florestan]

Well anyway, thanks for all your help. I'll keep playing around with it and see if I can figure it out. If I do, I'll post here again just for the records.