mpeg4?

aznfs · Post by **aznfs** » Sun Jul 18, 2004 10:05 pm

sysKin wrote:Perhaps I'll explain?

MPEG4 is a multimedia standard, more formally known as ISO-14496.

It consists of several parts, such as:
- ISO-14496-1, known as "MPEG-4 Systems", describes lots of things, like mp4 container.

- ISO-14496-2, known as "MPEG-4 Visual", describes a video compression standard - the one implemented by divx 4,5, xvid, 3vix, nerodigital, etc.

- ISO-14496-3, known as "MPEG-4 Audio", describes AAC audio compression.

I hope that helps,
Radek

i well explained

Maver · Post by **Maver** » Sun Jul 18, 2004 10:35 pm

so it was orginaly made by apple and theres differn't morphs of it like divx and xvid... dvds are mpeg2 right? why not mpeg4? and can my dvd player play mpeg4? and if it can, can it also play like xvid? and if its a compression standard then how come i can't find it in my list of endcoding for avi (or can you not put mpeg4 in an avi container(unless its xvid ect)?)? lol

Kalium · Post by **Kalium** » Sun Jul 18, 2004 10:54 pm

Maver wrote:so it was orginaly made by apple and theres differn't morphs of it like divx and xvid... dvds are mpeg2 right? why not mpeg4? and can my dvd player play mpeg4? and if it can, can it also play like xvid? and if its a compression standard then how come i can't find it in my list of endcoding for avi (or can you not put mpeg4 in an avi container(unless its xvid ect)?)? lol

Let's take this bit by bit.

No, MPEG4 is not originally from Apple (AFAIK). It's an ISO standard. That means that for it to go into use one or more groups have to implement it.

Yes, DVDs are MPEG2. And no, I doubt it can handle MPEG4, although I've heard of some that can handle DivX.

As for why it's not in the encoding lost, well, XviD and DivX are two different implementations. They are not the same, so they show up as XviD and DivX, instead of MPEG4. Since MPEG4 can be both a container and a codec, it can be a stream inside an avi container.

There, I think I covered it all.

TaranT · Post by **TaranT** » Mon Jul 19, 2004 3:29 am

An MPEG4 FAQ (The MPEG Industry Forum)

Tab. · Post by **Tab.** » Mon Jul 19, 2004 5:03 am

.mp4 is the container or "systems" level of the MPEG-4 standard. The format itself is based heavily off Quicktime, which is where the idea that it was created by Apple comes from. It wasn't, but it was based off their work.

The DVD standard only defines MPEG-2 for video compression (and PCM, AC3, MP2 for audio), so no, DVD players cannot inherently play MPEG-4. However, a lot of current players do support MPEG-4 video in avi (and sadly, only a few... if any, in .mp4).

MPEG-4 part 2, Visual, defines the video compression technology that, if implemented correctly, can be decoded by any MPEG-4 compliant decoder. XviD and DivX 4.x-5.x are two implementations of this encoding technology. They also happen to use the VfW api for encoding, meaning they show up on the compression list in VirtualDub and their output can be stored in .avi. It's still MPEG-4 video, it just goes to show that the standard's compression format is independent of the container format. avi, however, isn't the greatest container for MPEG-4 and there are advantages to using the standardized container format. For these reasons, the full scope of MPEG-4 (video, audio, and systems) will be covered in detail in the EADFAG guide updates.

As a side clarification, referring to MPEG-4 video distinctly as XviD or DivX is akin to referring to MPEG-1 as TMPGenc or CCE. In reality, each is merely a different encoder for the same generic format.

Take a look here and here for more info.

Maver · Post by **Maver** » Mon Jul 19, 2004 10:02 am

wow thanks for all the info more then i was expecting! why don't people use divx or xvid insted of the core mpeg4?

Zarxrax · Post by **Zarxrax** » Mon Jul 19, 2004 10:04 am

Maver wrote:wow thanks for all the info more then i was expecting! why don't people use divx or xvid insted of the core mpeg4?

Divx and Xvid *ARE* Mpeg-4. There is no "core" mpeg-4.

Tab. · Post by **Tab.** » Mon Jul 19, 2004 10:28 am

Maver wrote:wow thanks for all the info more then i was expecting! why don't people use divx or xvid insted of the core mpeg4?

That question makes no sense whatsoever.

Zero · Post by **Zero** » Mon Jul 19, 2004 12:09 pm

Maver wrote:wow thanks for all the info more then i was expecting! why don't people use divx or xvid insted of the core mpeg4?

Simple. Makes plenty of sense. Codecs drain hardware because they must decode a video to play it. Not everyone packs l33t machines like some of us have (at one point I had a terrible machine that would barely play anything) and MPEG-4 is easier to decode and can be slightly better quality. (Think the difference between .jpg and .bmp)

-Zero

Tab. · Post by **Tab.** » Mon Jul 19, 2004 12:54 pm

...
Have you read any of this thread?