I'm not getting the advertised 24Mbps out of my Canon HFS10

[Larry Horwitz]

As my earlier post in this thread indicated, I am pretty certain that Apple does not yet handle the 24 Mbit/sec rate in AVCHD. Very few video editing program do.

The camera is NOT at fault in my opinion.

Larry

[Larry Horwitz]

To confirm my original theory, I invite you to download a brief 24 Mbit/sec sample .mts file at the link below.

I am guessing you will have the very same experience with this Canon 24 Mb/s file as you do from your own camcorder.

Larry

http://av.watch.impress.co.jp/docs/20080723/ezsm021.mts

[Predrag Vasic]

When you "transfer" video from AVCHD into FCP, you are converting that video from AVCHD to Apple ProRes 422 codec. In other words, the video files you get in FCP are not the original AVCHD files; they are in entirely different codec, and different size.

The only way to find out the actual bitrate of an AVCHD file is to open the original file in VLC (VideoLan player) and look at "Media Information". There you can easily see the exact bitrate of the video.

AVCHD is extremely difficult to work with on all but fastest computers. Some of the Windows PCs may have a slight advantage to the comparable Mac in that they may offload some of the heavy decoding to the display card hardware. Either way, it is much easier to edit AVCHD by not editing it directly; instead, transcoding to something larger, but less compressed and easier to work with (ProRes in FCP, AIC in FCE/iMovie, or perhaps Cineform on Windows).

On a Mac, the only software package that allows you to edit AVCHD files directly is Premiere. It is an unpleasant experience when doing it directly to the AVCHD.

In Windows world, there are about half a dozen major packages that can edit AVCHD directly (Sony Vegas, Premiere Elements, Pinnacle Studio, etc). The experience is still very unpleasant. Transcoding is still the best way.

So, try it with VLC and check the itrate there. It should be 24Mbps or close.

[Larry Horwitz]

Originally Posted by Predrag Vasic

In Windows world, there are about half a dozen major packages that can edit AVCHD directly (Sony Vegas, Premiere Elements, Pinnacle Studio, etc). The experience is still very unpleasant. Transcoding is still the best way.

I really don't agree. I've been editing h.264 and similarly comppressed formats for years, including AVCHD which I started using in 2006. While I will readily admit that it WAS "very unpleasent" years ago, the introduction of quadcore machines a few years ago made a huge difference.

I very strongly dislike the wasted time and quality loss which transcoding requires, and much prefer to use software which natively handles AVCHD very well.

Personally I prefer Cyberlink Power Director 8 Ultimate and VideoReDoTVSuite (h.264 version) for doing cut editing, as well as other software for quick AVCHD processing.

AVCHD disks made on the Mac look noticeably softer than the Windows equivalents owing to the transcoding and down-rezing I have encountered, and take much more time to create.

Larry

[Tom Gull]

I agree with you, Larry. Having the requisite QuadCore and Vista 64 with 6GB of memory, I never transcode to edit. I start with AVCHD files and I end up with AVCHD files. If I want to post to YouTube after editing, I'll still create an AVCHD file and then convert it to MPEG-4 HD for the upload. But I figure all of this is somewhat like taking the same JPEG and editing it over and over again. Each re-encoding will cause some quality degradation, so doing really serious ones or doing them repeatedly isn't a good idea with lossy compression. Of course, I'm assuming each frame isn't stored and edited individually and we ARE talking about lossy compression... ???

[Larry Horwitz]

Tom,
Just as you predicted, h.264 is especially lossy, and this is, in fact, the feature which allows it to compress to a far greater extent that any of the other codecs. AVCHD files are nominally less than half the size of mpeg2 files for the same perceived quality.

The penalty for transcoding and recompression becomes greater with h.264 as compared to, let's say, mpeg2, and thus I am especially opposed to transcoding to another format.

Given the low cost of quadcore hardware today (a complete system for well below $1000) and the recent introduction of 6 core CPUs which will further drive the price of quadcores down, I can see no good reason to recommend video editing on a dual core or single core machine, except for the rare situation where a low cost laptop is required. For that situation, I would readily admit that AVCHD editing might be "Very unpleasant" unless first transcoded. Even in this case, I would hate to have to wait for the transcodes to and from mpeg2. They would take 10 or 20 times real time based on my experiences.

Larry

[Paulo Teixeira]

Just about every single user that have tried Edius Neo 2 Booster are very impressed with the native AVCHD editing. They've hit a home run with that software.

[Ron Evans]

The same technology will come to Edius Pro with the upgrade to version 5.5 around NAB time.

Ron Evans

[Evan C. King]

Originally Posted by Craig Terott

Going alone with your theory. I would expect to see 21Mbps or 22.5, or even 19Mbps. I could except that. But when a camera is rated for 24Mbps I doubt it would vary by that much. I've never seen anything above 14.3? And shooting a busy scene? Don't think so.

Once it hits iMovie it becomes AIC (Apple Intermediate Codec) so the usual AVCHD bit rates won't apply. The rate will now be based on AIC's rates. Also make sure you're looking at 14.3Mbs(megabits) and not 14.3MBs(megabyes) with what I know about AIC it's probably MB you're actually looking at which is higher, which is why the footage grows in size once you import.

[Paul Rosco]

Prores on Final Cut should be able to handle your 24 bit avchd files without noticable reduction of quality. It is considered lossless or near lossless by many of it's users.