[roman700]

Hi

What is the difference between MPEG2 and MPEG4?

Is it true that 2 is better than 4, that DVD camcorders record in MPEG2 and video that goes on memory cards is recorded in MPEG4 generally?

What other formats exist? What goes on miniDV tape?

Thanks a lot.

[vonhosen]

MPEG-4 is a newer more efficient codec than MPEG-2

It has more efficent compression meaning you can get as good (or maybe better) picture for less bitrate & so I wouldn't say MPEG-2 is better.

Both MPEG-2 & MPEG-4 can be used for Hi-Def but MPEG-4 is attractive to broadcaster's because of it's increased efficency freeing up bandwidth.

It is true that recording to memory disc on camcorders uses MPEG-4 (again because of better compression) although I never record to memory disc with a camcorder.

[MartinImber]

MiniDV has some basic compression, but I don't know what it is but DV is 1/5 the size of raw digital.

BUT HD DV uses MPEG2

[MarkE19]

A mini DV cam does 5:1 compression onboard the cam (hardware codec)before writing the file to tape. The file on the tape is AVI (audio video interleaved).

Also as Martin has said the new HD DV cams that are starting to become available use MPEG-2 compression onboard.

Standard prerecorded DVD's and those recorded on a DVD camcorder, PC or standalone DVD recorder are recorded with MPEG-2 compression.

MPEG-4 is the compression used for DIVX and web based video which is lower quality than MPEG-2. I'm not sure if it is capable of being better than MPEG-2, but doubt it.

Mark.

[Dutch]

MPEG4 AVC HP (Advanced Video Codec High Profile) is the codec used on HD DVD and Blu-ray, and will also be used for HD broadcasting next year. It is 2 or 3 times more efficient than MPEG2 with better PQ too.

Steve