Please explain .mpeg .mpeg2 .m2v files

[mallen]

The more I try to read about this stuff the more I get confused. I am using a Videoh! PCI capture card. I didn't know it captures in Mpeg2. Someone here said it does and the description on this site says it does. But the box and manual say nothing about that. But here is my question. When I capture the file the extension is mpeg? If I right click on it the properties just say mpeg. Is this really a Mpeg2 file? Becuase when I export it from TMPGEnc it creates a m2v file and a wav file. Can someone explain this?

[redwudz]

Everything I see says it's a MPEG-2 capture. You can take the file and put it into AVIcodec or Gspot and it will tell you what it is.

M2V is the video portion of a MPEG-2 file and WAV is the audio portion, uncompressed. You usually convert the WAV to MPEG-1, layer 2 or AC3 audio which is much more compressed and saves space on a DVD for higher video quality. You should be able to put these two files into an authoring program like TMPGEnc DVD Author and it will convert both of the files into DVD compatible files to burn on a DVD burner.

There are plenty of guides to the left to give you the whole sequence from capture to DVD.

[daamon]

Hi mallen,

MPEG is a format.

When video is stored in MPEG format, it is compressed using an MPEG codec - compressor / decompressor. A codec is basically a set of rules on how to compress and decompress the appropriate file.

When compressing, a bitrate is used to dictate how much is kept, and how much is got rid of - the lower the bitrate, the less information is retained = higher compression (i.e. more information is "thrown away" away), resulting in a smaller (more compressed) file, but less quality coz there's less information.

VCD MPEG1 uses a low bitrate of 1,150kbps
SVCD MPEG2 uses higher bitrates - up to 2,600kbps.
DVD MPEG2 uses higher bitrates still - up to around 10,000kbps.

Calling it MPEG1 or MPEG2 etc. is just a way of identifying what type of MPEG it is, based on the specifications for each standard - see "What Is..." (links, top left of the page) for the full specs of each type.

Either way - all MPEGs can either be:

1. video + audio.mpg - Called a "System Stream"
2. video only.mpg - Called a "System Stream"
3. video only.m2v - Called an "Elementary Stream"

There may be others...

I won't go into the "audio only" files as I'm not totally sure of the extensions (.???), and they're not so relevant to your question.

An audio.wav file is uncompressed audio.

I hope that gives you some insight, and answers your question.