View Full Version : AVC Intra Question


David Ziegelheim
August 7th, 2006, 05:18 PM
If the AVC-Intra format processes 1080i60 4:2:2 10-bit info at 50Mb/sec vs DVCProHD recording 1080i60 4:2:2 8-bit at 100Mb/sec, and Panasonic has a version of DVCProHD that record 720p24 4:2:2 8-bit at 40Mb/sec, does that mean a 720p24 AVC-Intra might be 20Mb/sec? If so, does that mean it may be possible to record it to DV tape?

Greg Boston
August 7th, 2006, 05:25 PM
Dave,

AVC-Intra is not the same as AVCHD. We have to be careful about intermixing the two terms here cause it could create lots of confusion.

-gb-

Douglas Spotted Eagle
August 7th, 2006, 05:33 PM
It's already creating lots of confusion in a different thread, I hope we can find our way to creating a forum specifically for AVC-I in the event it becomes a reality at some point. Very frustrating to keep reading posts about the "potential of AVC-I" in a discussion of a consumer format.

David Ziegelheim
August 7th, 2006, 06:40 PM
AVCHD and AVC-Intra are just different versions of the same spec. There are 7 profiles and a whole bunch of levels. Isn't AVC-HD either the Baseline or Extended level? AVC-Intra is probably Hi422. Both are probably level 4.

Just different version of the same spec. The P2 AVC announcement seems to just talk about AVC vs DVCProHD with a doubling of storage.

I am very confused about the bit rates of the different levels, however 1280x720@60 doesn't exist until level 3.2. 1920x1088@30 until level 4.

Chris Hurd
August 8th, 2006, 01:37 AM
Until there's actual hardware, this is all just pointless measurbating... as counterproductive as it is vigorous.

Meanwhile for Spot: obviously we'll need to run a separate AVC-I board, when the time is right (that is, when some kind of AVC-I product gets announced).

David Ziegelheim
August 8th, 2006, 02:30 AM
I believe the chips and software exist. Well, HP/level 4 exists. The Hi422p standard was adopted 2 years ago; so hardware should exist. I think papers have been presented. The key may be what Barry Green said...AVC will replace all current recording formats in a very short time. A short enough time that it affects camera procurement planning.

Not counting processing speed issues, if Panasonic modifies its 720pN24 for the new format, will it be recordable on tape?

Chris Hurd
August 8th, 2006, 07:09 AM
So far all versions of AVC recording media are tapeless.

The AVC format specification calls for recording to hard drive, optical disc or flash memory. Not tape.

David Ziegelheim
August 8th, 2006, 04:55 PM
I didn't see media specified or referred to in any of the H.264 presentations...a lot of stuff on algorithms though. It is a sequential bit stream, it should store on any medIa capable of sequential storage at an adequate rate. It is also specified for over the wire transmission including video conferencing (replacing H.263) and video phones.

The thing that got me to start this thread was the possiblity of storing an H.264 version of Panasonics 720pN24 to standard, already in the camera, tape drive. That format is not in the standard though.

Jeffery Haas
June 18th, 2007, 11:50 AM
I imagine that Focus Enhancements will most likely try to offer support for the codec in a future upgrade.