Canon's new 50Mbps MPEG-2 Full HD (4:2:2) codec

[Monday Isa]

I hope my electricity doesn't go out here in Baltimore with the snow storm we are about to get. I'd love to be updated tonight on this new camera.

[Mark Fry]

Looks like another example of Canon video cameras moving up in the world. 50Mbps 4:2:2 is a similar step up from HDV, in terms of quality and complexity, as HDV was from DV. However, I fear that it may be above my budget and computer-power. Also, it makes the gap between the Vixia/HV40 and the "pro" line even bigger.

Is it too much to hope for a camera about the size of an XM1/VX2000 that squeezes the best resolution possible out of 20-25 Mbps codecs? I know Canon could do it, but I wonder if they think they can make money from such a camera?

[Tim Polster]

Hello Mark,

From my experience with the Nanoflash, 50mbps 4:2:2 is not a system strain at all, especially if it is full raster, (square pixles).

[Chris Hurd]

Will post photos from tonight as soon as I can, however there may be a bar or two in between me and the computer.

[Dom Stevenson]

Good for you Chris. So we may have to wait until Monday.

Looks like i'm going to have to get drunk all weekend.

[Mark Fry]

Have a great time tonight, Chris. If you get the chance, please ask them about my "HD-XM1" - Cheers!

[Robert M Wright]

Originally Posted by Mark Fry

Looks like another example of Canon video cameras moving up in the world. 50Mbps 4:2:2 is a similar step up from HDV, in terms of quality and complexity, as HDV was from DV. However, I fear that it may be above my budget and computer-power. Also, it makes the gap between the Vixia/HV40 and the "pro" line even bigger.

Is it too much to hope for a camera about the size of an XM1/VX2000 that squeezes the best resolution possible out of 20-25 Mbps codecs? I know Canon could do it, but I wonder if they think they can make money from such a camera?

A higher bitrate doesn't create more computations for the CPU (and HDDs can easily maintain thruput at way over 50Mbps). Editing the 50Mbps MPEG-2 out of this new Canon won't be any tougher for you than editing HDV out of an HV40.

As far as squeezing best image quality (assuming that's what you mean by resolution) out of a codec at 20-25Mbps, that would be AVCHD. No need to hope. Such cams already exist. Panasonic and now Sony make prosumer AVCHD cams that are similar in sizes to the XM1 and VX2000 (both in terms of chassis sizes and imaging chip sizes). The HMC150 doesn't shoot anything akin to "best resolution possible" (fairly low resolution imaging chips for an HD cam) but does shoot a very nice image otherwise. The HMC40 shoots a very high resolution image, and the new Sony AVCHD cams should as well. AVCHD is a lot tougher on CPUs, for editing purposes, though.

[David Heath]

Originally Posted by Mark Fry

50Mbps 4:2:2 is a similar step up from HDV, in terms of quality and complexity, as HDV was from DV. However, I fear that it may be above my budget and computer-power......

Is it too much to hope for a camera about the size of an XM1/VX2000 that squeezes the best resolution possible out of 20-25 Mbps codecs?

It's as Robert says - 50Mbs MPEG2 should cause far fewer computer issues than going to AVC-HD. That's as true in the camera as the NLE, AVC-HD requires far more power to code than MPEG2, certainly to do it well and get significant bitrate savings and here power can mean both in the computing sense and the no of watts.

At one time, a move to AVC-HD was seen as the only way to be able to get HDV or better quality onto solid state media that cost less than P2 or SxS. That was proved untrue firstly when SDHC cards were used in the EX, then the JVC cameras using SDHC natively for the 35Mbs codec. The only advantage of going to AVC-HD is that a lower bitrate will mean more recorded minutes per GB, but with the price of consumer memory what it is I don't think it's worth it. (At least at the prosumer level, consumer cameras are a different matter.) Unless the spec is rewritten and extended, there is no form of AVC-HD that will support 4:2:2.

What the marketing people will do is another thing again. They may only put the 50Mbs codec into the higher end models, but theoretically there is no reason why it shouldn't be fairly cheap to implement into fairly low end models.

[Robert M Wright]

We don't know what media Canon's cam will record onto yet. Hopefully it will be something standard (not proprietary, like P2 or SxS). Class-6 SDHC won't cut it for recording at 50Mbps though. My guess is that it will be SDXC that works okay with "class-10" SDHC cards (which are at least reasonably affordable nowadays - not several hundreds of dollars for just a 16GB card, like with P2).

[David Heath]

Originally Posted by Robert M Wright

Class-6 SDHC won't cut it for recording at 50Mbps though. My guess is that it will be SDXC that works okay with "class-10" SDHC cards......

Class 6 SDHC should record basic 50Mbs with few problems - issues may come if used for any overcranking, though. The limitations on the EX are more to do with the adaptor and interface than basic card speed, but even allowing for those it will still allow a limited degree of overcranking (so faster than 35Mbs recording). If used in a device specifically designed for it's use, class 6 SDHC should work fine. Maybe a recommendation of class 6 for normal speed, class 10 for overcrank?

My own preference would be for Compact Flash, and even a fairly basic form such as Sandisk Extreme III should work with full 60fps overcrank to 50Mbs. (2.5x speed, and hence datarate, so recording at 125Mbs.) See the recommendations from Convergent Design regarding CF with the nanoFlash - http://www.dvinfo.net/forum/converge...rd-matrix.html - they rate Extreme III at 180Mbs, which gives a nearly 50% safety margin, even for full overcrank.

But we'll soon see what it actually takes!

[Robert M Wright]

Class-6 is fine for recording at 35Mbps, but not at 50Mbps.

The core requirement for class-6 (SDHC cards) is the ability to sustain write speeds of 6MBs. 6MBs (six megabytes per second) is 48Mbps (forty eight megabits per second), which is not quite (by spec) assurance of reliable sustained writing at a speed of 50Mbps. If an SDHC card that precisely meets (without exceeding) the class-6 spec were used, there would be recording failures (with absolute certainty) trying to write to the card at 50Mbps.

Also, it's never good to cut really close to specs anyway. In otherwords, even if the camera recorded MPEG-2 at say 46Mbps, that would be uncomfortably close to the class-6 spec, and recording with borderline cards would assuredly be problematic (and a lot of class-6 SDHC cards out there are indeed borderline, or just plain do not quite cut it technically for meeting the spec).

That said, class-10 cards (while not officially an SDHC spec) should work fine, and are available nowadays.

[David Clark]

Originally Posted by Chris Hurd

Not sure when the official press release is going out, it's either tonight or first thing Monday morning, but I'll post it as soon as I receive it. Will post photos from tonight as soon as I can, however there may be a bar or two in between me and the computer.

Chris...We love ya man!!!!

[David Heath]

Originally Posted by Robert M Wright

The core requirement for class-6 (SDHC cards) is the ability to sustain write speeds of 6MBs. 6MBs (six megabytes per second) is 48Mbps (forty eight megabits per second), which is not quite (by spec) assurance of reliable sustained writing at a speed of 50Mbps. If an SDHC card that precisely meets (without exceeding) the class-6 spec were used, there would be recording failures ...........

Point taken, though my understanding of the class rating (unlike the older speed ratings) is that they represent absolute minimums which the product should reach, and not "typical" speeds. Hence the vast majority of class 6 should be better than that minimum, and well within spec for 50Mbs - which is what the results shown up in EX tests seem to indicate. But I suppose if I was selling the camera and was answerable .......... :-) So maybe class 10 it had better be......

I still favour Compact Flash. It's more rugged than SD, and the de facto standard for professional stills photographers. The smaller the device, the more suitable SDHC may be, but for a camera of this size that shouldn't be a problem, any more than it has been in most DSLRs.

[Chris Hurd]

This joint's jumpin'! Lots of people here. Some news: Canon USA says the press release for this camera will not be issued until NAB.

Also -- tune into http://www.supermeet.com/live for the realtime webcast (I think I got that URL right... no, I have not had any cocktails yet).

[Robert M Wright]

Originally Posted by Mike Dontigney

Maybe Raid 0 SDHC?

That would be a lot uglier to implement, than simply going with SDXC, and making sure to be compatible with SDHC (FAT 32) to assure that there is reasonably affordable media ("class-10" SDHC) that indeed works in the mean time, until SDXC cards are commonplace (which shouldn't be all that far in the future really).

A RAID approach to recording with flash memory would require more than simply sticking the card in a card reader (after recording with the camcorder), to copy the footage to computer (or edit directly from the card). It could be made to work, but there's really no reason to strap customers with that sort of hassle.