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View Full Version : What's The Difference Between A Format And A Codec?????


Sawbones
19th September 2005, 22:37
I had done a bunch of conversions between formats for years, but only recently started doing some serious work with movies and video files......

I had thought that if you converted to the avi format, you would automatically use an avi codec, and so on....

About 2 months ago, I realized that I could convert from let's say an mpeg to an avi using the huffy codec, and other variations as well.....

Now I'm all confused....

Can anybody explain this in somewhat simple terms???

Guest
19th September 2005, 23:24
Let's say you want to get from point A to B. The mode of transport is your format: car, plane, or ship. If your format is car, you have different car makes to choose; that is your codec: Chevy, Dodge, Yugo.

AVI is what we call a container format. You can put various compression types inside. Each compression type has a corresponding codec.

Sawbones
20th September 2005, 00:21
Let's say you want to get from point A to B. The mode of transport is your format: car, plane, or ship. If your format is car, you have different car makes to choose; that is your codec: Chevy, Dodge, Yugo.

AVI is what we call a container format. You can put various compression types inside. Each compression type has a corresponding codec.


Thanks...

That was perfect....

So would the codec be responsible for any quality degredation in the conversion, or would that be the format....

Or both??

Guest
20th September 2005, 00:26
The codec.

But if you choose a format that is limited to crappy codecs...

Sawbones
20th September 2005, 00:45
The codec.

But if you choose a format that is limited to crappy codecs...


Understood....

I'm more concerned with the picture slowing down or stuttering, and blockiness...

Otherwise, I'm OK with tv quality....

Gonna try the huffy again tough and play with that a bit....

I had some great times with the alparysoft codec.....

Knocked my file sizes down to half in lossless mode.....

But I couldn't play them on anything....

Guest
20th September 2005, 01:34
You have to understand the different types of codecs and what they are good for. Not all are good for distribution and playing.

For example, HUFYUV is lossless; it will not degrade the video. But its compression ratio is low. It is used as an intermediate compression and for capturing video.

AlparySoft Lossless also will not degrade the video but it is slow, so may not play smoothly on some machines.

You can also use uncompressed RGB in a container. That is usually very hard to play smoothly because the data rate is so high.

A good codec for general purpose final production, and thus for distribution and playing, is XviD.

Actually, "format" is a bit ambiguous. You might call Xvid a format. It's better to refer to "containers" and "codecs" to avoid confusion. AVI is a container (so is Matroska, etc.). HUFYUV is a codec, i.e., a type of video compression/decompression. Don't forget that the container has to hold the audio as well, which is usually also compressed.

Sawbones
20th September 2005, 01:51
You have to understand the different types of codecs and what they are good for. Not all are good for distribution and playing.

For example, HUFYUV is lossless; it will not degrade the video. But its compression ratio is low. It is used as an intermediate compression and for capturing video.

AlparySoft Lossless also will not degrade the video but it is slow, so may not play smoothly on some machines.

You can also use uncompressed RGB in a container. That is usually very hard to play smoothly because the data rate is so high.

A good codec for general purpose final production, and thus for distribution and playing, is XviD.

Actually, "format" is a bit ambiguous. You might call Xvid a format. It's better to refer to "containers" and "codecs" to avoid confusion. AVI is a container (so is Matroska, etc.). HUFYUV is a codec, i.e., a type of video compression/decompression. Don't forget that the container has to hold the audio as well, which is usually also compressed.


Cool...

Thanks for all the info....

mg262
20th September 2005, 11:54
I had some great times with the alparysoft codec.....Watch it with that one. I ran a comparison of lossless codecs some time back, and the alparysoft "lossless" codec turned out not to be lossless after all. The bug may have been fixed by now but it's worth checking (by compressing/decompressing and comparing with the original) before using it for any real task.

Sawbones
3rd October 2005, 23:26
Watch it with that one. I ran a comparison of lossless codecs some time back, and the alparysoft "lossless" codec turned out not to be lossless after all. The bug may have been fixed by now but it's worth checking (by compressing/decompressing and comparing with the original) before using it for any real task.

Thanks for the heads up...

I've been playing with formats and codecs and everything else related to try to find something I can be happy with.....

I have one file that I use as a test file, but I need to be sure, as you mentioned , that I got what I want before I go and do my whole collection....

CWR03
4th October 2005, 07:41
Depending on your collection, you should be aware that you may run into formats that require different encoding methods. An example would be video that's been telecined.

Sawbones
5th October 2005, 00:55
Depending on your collection, you should be aware that you may run into formats that require different encoding methods. An example would be video that's been telecined.


Yeah, I sorta planned on that.....

(Translation: I've been putting off that possibility for as long as I can) :D


I don't think I'm gonna have too much of a problem though.....

I ripped my dvd collection onto my hard drive using the one big file rip, as opposed to the files being broken up like they are on a dvd normally.....

And I'm only going to view them on my computer, (tv broadcast quality), anyway.

I don't plan on ever buying a standalone player as long as I have a dvd drive.....

I've seen digital tv and hd-tv, and quite frankly, I'm not impressed.....

Nor am I impressed with surround sound and all that other junk...

I am very easy to please....

I'm just happy watching tv quality movies with basic stereo sound on my 17 inch monitor....

And with those factors in mind, I could reduce the video and audio to that basic level, and it should yeild a much smaller overall file size...

Unfortunately, most of the conversion programs are designed for the output that will be playable on standalone players, but I'm trying to work around that....

If I ever do get that big screen hd-tv, or standalone player, I always have my original dvds to work with, which I keep safely archived....

I though about blu-ray for archiving the video files in full size as data files, but the information on whether the internet hookup is required for all uses is vauge at best, so I'm gonna wait on that.....

Also, required internet hookup is the reason why Windows XP will be the last Microcrap product I ever will buy.....

CWR03
5th October 2005, 01:28
I only mentioned being aware of needing different techniques so you wouldn't do one encode and like it, then queue up 50 more and find a lot didn't work properly. In almost all cases, a batch of movies will come out great with all the same settings, as long as the aspect ratio is correct. I've only run into problems with some TV series.

A good HD signal can make a world of difference in the picture quality - I've seen Discovery HD on a 62" Panasonic plasma, and it was like looking through a window (with one eye closed, since there's no depth). A DVD on the same screen looks like crap.

I've moved to larger file sizes while backing up my DVD's - I'll make a 2-hour movie half-DVD size, keeping AC3 audio, and there's virtually no loss of quality. I'm with you, as long as I have a PC running with DVD-ROM drives, I see no reason to own a standalone player. (I have one PC connected to my TV and the PC's networked, so I can watch any file on any computer anywhere.)

Both AutoGK and Gordian Knot have the ability of standalone support, but neither is specifically geared toward that end.

Microsoft will send you updates via mail, and will allow you to validate the product by phone or fax. It's much easier to do it via internet connection, but it's not necessary.

Sawbones
5th October 2005, 02:40
I only mentioned being aware of needing different techniques so you wouldn't do one encode and like it, then queue up 50 more and find a lot didn't work properly. In almost all cases, a batch of movies will come out great with all the same settings, as long as the aspect ratio is correct. I've only run into problems with some TV series.

A good HD signal can make a world of difference in the picture quality - I've seen Discovery HD on a 62" Panasonic plasma, and it was like looking through a window (with one eye closed, since there's no depth). A DVD on the same screen looks like crap.

I've moved to larger file sizes while backing up my DVD's - I'll make a 2-hour movie half-DVD size, keeping AC3 audio, and there's virtually no loss of quality. I'm with you, as long as I have a PC running with DVD-ROM drives, I see no reason to own a standalone player. (I have one PC connected to my TV and the PC's networked, so I can watch any file on any computer anywhere.)

Both AutoGK and Gordian Knot have the ability of standalone support, but neither is specifically geared toward that end.

Microsoft will send you updates via mail, and will allow you to validate the product by phone or fax. It's much easier to do it via internet connection, but it's not necessary.


Nice to see somebody out there that's as easy to please as me...

:D


The reason I brought Microsoft up is because they claim that you will not be able to view any content on you pc via thier next operating system unless it is digitally signed and can be verified by internet connection....

No ticky, no shirty....

I don't like the idea that I am required to hook up to the internet just to watch a movie that I purchased on my own PC......

But the larger issue is that I have over 1 terabyte of video and audio content that is completely legal, not copyrighted, and I guarentee has no digital signatures.....

This is in the form of free music, home movies, both 8mm transfers and newer camcorder stuff, non copyrighted images, and of course, free porn.....

When I called Microcrap to find out if I would be able to play this stuff on their new OS the only answer they had was to refer me to the press releases on thier website.....

Which is a nice way of telling me to screw myself......

And knowing how little billy gates just loves to see what he can get away with next, I wouldn't put it past him.....

I also called over 5 dozen hardware manufacturers to see who was actually putting this "DRM" stuff into their hardware, and about 40% said yes, 40% said they are not allowed to talk about it, and the rest simply said, no comment and hung up on me....

But asking about all this stuff, I figured out how to make the whole drm issue go away.....

Just don't buy vista....

No amount of hardware is going to anything but sit there without the software to back it up.......

:D :D

P.S. - If you bought your PC prior to January of 2004 or thereabouts, chances are that you have little to no DRM built into the hardware.....

So if you install vista on that machine, it will lock you out of your content because your hardware is not DRM compliant.....

Cheers......

Caroliano
5th October 2005, 13:28
I would call .avi an container, that join audio, video, subs, tags, etc together and organize it. There may be an limit of types of audio and video and other things that you can store in an container. Like, you can't put Vorbis sound in an .avi (well, there are is a bad way to do that, but shoud not be considered). You can see an better descripition in Matroska's Page (www.matroska.org), that is another container.

Format for me is more related to an standart, like windows media or MPEG 4 for example. The codec is the one that compress the audio and video. They can obedey an standart, as Xvid and Divx are MPEG 4 codecs and LAME, Xing, Fhg are all MP3 encoders, or create their own standart, like Vp7, Vorbis, Dirac, etc.