Silly question: is H264=MPEG4?

[MuzzleVelocity]

Ok, when I’m streaming from my USB webcam to a local file, I have options for the video Codec H-264 and also one called MPEG-4 (among others). H-264 works for me, but MPEG-4 doesn’t (Codec not found error).

But I thought they are the same thing. I am trying to educate myself on the distinction between containers and codecs, and for instance the wikipedia article on H264 says “The ITU-T H.264 standard and the ISO/IEC MPEG-4 AVC standard … are jointly maintained so that they have identical technical content.”

So why are there choices for both, and why does only work and the other doesn’t? Is the wiki article wrong, or is this maybe a bug in VLC?

Thanks in advance for any help, this is a great community, keep it up!

[Jean-Baptiste Kempf]

mp4v is Mpeg4 part 2
H264 is Mpeg4 part 10

[Lotesdelere]

What VLC is calling MPEG-4 is MPEG4-ASP from MPEG4 part 2 specs.
The most known implementations of MPEG4-ASP are Xvid and DivX. This is now a quite old format but it's still widely used and most, if not all, standalone players can decode videos using this format.

H.264 is now another name for MPEG4-AVC from MPEG4 part 10 specs.
It's one of the formats used for HD video and HD TV. It's much more efficient than MPEG4-ASP and will give a better image quaity at the same bitrate. The downside is that it needs much more CPU power for both encoding and decoding. Not to mention that the hardware compatibility is quite limited for now and some players (software as well as hardware) have strict limitations and can't decode videos which are exceeding these limits (e.g. resolution, bitrate, CABAC, B-frames).