What exactly is AVCHD?

Question

Is it a codec? I don't think so; I believe it uses MPEG4/H.264 for video and AC3 for audio.

Is it a container format? Doesn't seem to make a huge amount of sense; there are enough out there already and it's likely that a suitable one already exists.

Is it simply a specification that specifies a particular combination of pre-existing technologies? But this would imply that AVCHD files could also be called something else, like "MPEG4 container with H264/AC3 inside".

So what exactly does AVCHD mean?

Answer 1

I think this image from Wikipedia says it best:

AVCHD is not a codec, but it is also not just a container.

Just like "every other" container, AVCHD features:

• Video streams
• Audio streams
• Subtitles

But in addition, for example:

• Playlists
• Menu presentation (like in a DVD)

Is it simply a specification that specifies a particular combination of pre-existing technologies?

Yes.

But this would imply that AVCHD files could also be called something else, like "MPEG4 container with H264/AC3 inside".

But who would like to call it that? Several other specifications take already existing specifications, remix them, and they aren't called "Open Source Container format for XYZ".

I think it's a "one format fits it all" mentality, which is why you'll find AVCHD on many consumer devices.

Answer 2

AVCHD is basically just a consumer name for H.264, which in turn is another name for the ISO standard MPEG-4, Layer 10. It is one of the most significant steps forward in video encoding in recent times.

To the very best of my knowledge, it is a codec since it is used to encode and decode video but it is also a specification.