Question about codec's

[carl606]

Hello there.
I am not sure if this is the right forum for this.
I have a question about codecs, i know .AVI , .MOV are containers for such codecs.

So is MPEG -1 , MPEG -2 , MPEG -4 , VORBIS, DIVX, are these the actual codecs inside these containers
And how do you know what a particular container uses what codec's......

Sorry if the question is a little vaigue , i am just a beginner on the suject.

[aedipuss]

you can use mediainfo or gspot on a video file to get the specifics of what it contains.

[porfitron]

From a DivX perspective, we like to see MPEG-4 ASP in .avi or .divx containers with MP3 audio, although AC3 audio can be played, too. Even though you can put just about anything in an .mkv container, we narrowed our presets to H.264 video (@L.4.0) with AAC audio, although MP3 and AC3 would be played, too - we call this HD format DivX Plus HD. The reason for our more strict presets is we want to make sure that DivX files can be played back on DivX Certified devices (HDTVs, mobile phones, DVD players...). All of our formats support multiple audio tracks and subtitles (e.g. SRT), and DivX Plus HD certified devices will be coming out soon (e.g. Philips Blu-ray players, Seagate HomeTheater+...), so they'll play all the flavors of .avi, .divx and .mkv I just mentioned.

[carl606]

you can use mediainfo or gspot on a video file to get the specifics of what it contains.

Thanks aedipuss.

So this statement is correct

I have a question about codecs, i know .AVI , .MOV are containers for such codecs.

So is MPEG -1 , MPEG -2 , MPEG -4 , VORBIS, DIVX, are these the actual codecs inside these containers
And how do you know what a particular container uses what codec's......

From a DivX perspective, we like to see MPEG-4 ASP in .avi or .divx containers with MP3 audio, although AC3 audio can be played, too. Even though you can put just about anything in an .mkv container, we narrowed our presets to H.264 video (@L.4.0) with AAC audio, although MP3 and AC3 would be played, too - we call this HD format DivX Plus HD. The reason for our more strict presets is we want to make sure that DivX files can be played back on DivX Certified devices (HDTVs, mobile phones, DVD players...). All of our formats support multiple audio tracks and subtitles (e.g. SRT), and DivX Plus HD certified devices will be coming out soon (e.g. Philips Blu-ray players, Seagate HomeTheater+...), so they'll play all the flavors of .avi, .divx and .mkv I just mentioned.

Hey thanks porfitron.

Just a little advanced for me just yet, understood the first bit ,but you lossed me after that

[aedipuss]

some videos are in containers, others not. an mpeg-2 can be in a vob or just an .mpg so it just depends on what the video is going to be used for and how the author made it.

your statement is close enough.

[carl606]

some videos are in containers, others not. an mpeg-2 can be in a vob or just an .mpg so it just depends on what the video is going to be used for and how the author made it.

your statement is close enough.

OK aedipuss. thanks for replying.
Just to clarify a little, there are no codec's in a video/audio/sound file,or the container, the codec's have to be installed on your system Via VLC media player or windows media player..etc, which use there own codec's.
Or in the case of "WMP" windows has the codec's. (hope that sounds right)

and to get any technical information i would either use any of these to programs

you can use mediainfo or gspot on a video file to get the specifics of what it contains

[Cornucopia]

To clarify:

1. A codec (coder+decoder or compressor/decompressor) is just a program/algorithm for squeezing and unsqueezing a stream/file of media. NOT THE MEDIA ITSELF.

2. The media ALMOST NEVER contains a copy of the codec, it's just the RESULT of the compression/coding.

3. To use the analogy of a ROPE, a container is the rope. Media streams are THREADS that comprise the rope and are woven (MUXED) into the rope.

4. To continue the analogy, THREADS can exist on their own (as RAW media streams), but in this state they can't do the same things as ROPE.

5. To continue the analogy, the ROPE itself (container) cannot exist without the THREADS (raw media) that it contains.

6. The codec must be correctly installed on every platform/device that you want to use that kind of media. (Since Windows usually comes pre-installed with WMP codecs, you usually already have them covered)

BTW, an ".MPG" IS a container. It's either an MPEG1 System stream, an MPEG2 Program stream, an MPEG2 Transport stream, or an MPEG4 stream. If it were a raw video stream, it would be "*.mpv", "*.m2v" or something similar.

Scott