Transcoding AVCHD Takes Forever

[Tim Lawrence]

Ok, So I have a new MBP (i7 8RAM) and I also have Neoscene as well as FCP7.

With everything I've read I was assuming AVCHD would transcode i a reasonable amount of time, however my current estimate is it takes 2 to 3 times longer than real time (30 minutes + to do a 10 minute clip. Am I missing a trick somewhere here???

[Ron Evans]

Not sure what your doing but on my PC, a Q9450, so not as fast as the i7, it takes just less than half realtime to convert using either Neoscene or to Canopus HQ fine. Most of the time for single track, I edit native files in Edius Pro 5.5 or Vegas Pro 9 only convert for multicam with multiple tracks as it makes it easier on the PC though most with i7's report multiple tracks native is OK.

Ron Evans

[Tim Lawrence]

Update:

Using FCP7 Log and Transfer takes less than real time.

Neoscene actually took close to 5 times real time (I'm talking 50 minutes for a 10 minute clip here).

I have an email in to Neoscene.

[Robert Turchick]

I tried neoscene too and was not happy with the time it took. Also, I didn't see a difference in quality. My 8-core Mac Pro does log & transfer at 1/3 real time. Too spoiled to change!

[Robert Young]

Transcoding from AVCHD to Cineform on my i7 system is very fast- probably 1/3 RT or less.
If the conversion is not pushing all 8 cores into the 90% range, then something fixable is slowing the process down.
One common bottleneck is the hard drive configuration:
1) In my case the AVCHD files are on a SATA drive and the converted Cineform files are written to a seperate RAID 0 drive.
2) If you tried to write the Cineform files back to the same SATA drive that the AVCHD is being read from, the entire conversion could be slowed down substantially. Even more so if you were reading and writing to a single USB external drive.
The worst ever was the time I was reading the AVCHD from the camera SD card and inadvertently writing the Cineform .avi back to the card instead of the RAID. That was maybe 10x RT, and the cores were at 30%.

[Robert Turchick]

interesting! I'll have to give that a second look then. I have the HD config you describe but typically transcode back to the same drive the AVCHD files are on. Once again though, never bogs in L&T doing this.

[Robert Young]

Originally Posted by Robert Turchick

interesting! I'll have to give that a second look then. I have the HD config you describe but typically transcode back to the same drive the AVCHD files are on. Once again though, never bogs in L&T doing this.

It may not be the HD config in your case, but definitely with an 8 core CPU & plenty of RAM, the performance of CF software conversion of AVCHD is expected to be on par with FCP & other pro level programs. If you are not getting that speed, there has to be a bottleneck somewhere in the system.
As mentioned earlier, a good clue is the level of CPU usage- if it's not running all cores pretty much flat out, there is most likely a dam somewhere downstream.

[Randy Painter]

If your not using a scratch disk, then that's your bottleneck. Reading and writing to the same disk will make it crawl. If you haven't purchased one yet, if you can afford it, get a SSD external drive. Or at least get a 7200 rpm hard disk for your external. Pretty sure your internal drive is 5400 rpm's unless you have a SSD drive.

[Tim Lawrence]

Indeed FCP has a scratch disk. All of my drives (internal and external) are 7200 RPM.

I do not see a scratch disk for Neoscene. How do I set it up? Or can I use the same one?

Also, does Neoscene only change CF files to 4:2:2 or does it also change the prores files it creates to 4:2:2?

Thanks,

TL

[Amos Kim]

Would the quality of media reader affect transcode time?

[Robert Young]

Originally Posted by Tim Lawrence

Indeed FCP has a scratch disk. All of my drives (internal and external) are 7200 RPM.

I do not see a scratch disk for Neoscene. How do I set it up? Or can I use the same one?

Also, does Neoscene only change CF files to 4:2:2 or does it also change the prores files it creates to 4:2:2?

Thanks,

TL

You don't need to set up a "scratch disk" per se. You just need to be reading from, and writing to different drives.
The Cineform files have the highest data rate by far- so you want to write them to your fastest drive. In your case maybe you could try putting your AVCHD files on the external drive, and writing the CF files to your internal SATA drive.
CF conversion produces a 4:2:2 Cineform .avi or .mov file.

Another issue: Someone mentioned that they did a CF conversion and the image quality "didn't look that much better"
The newly created CF clip is not going to look any different than the original clip.
The two principle benefits from working with CF are:
1) CFHD.avi (mov) is easier for your computer to work with for editing than AVCHD, etc.
2) After applying graphics, filters, color correction, effects, and then beating up on the codec even more by transcoding to DVD, Flash, Blu Ray, & etc., Cineform will give you the best final image quality because, unlike AVCHD, it is "lossless" throughout the editing process. That's where you will see the difference in image quality- on the final delivery product.
So, the ultimate purpose of CF is the preservation of the original image quality throughout the editing and final output process.

[Robert Young]

Originally Posted by Amos Kim

Would the quality of media reader affect transcode time?

IMO, not likely.
AVCHD files are small/low data rate (16-24 mbs), so the card reader is usually not an issue.
If you have any doubts about it, transfer the clips from the card to one of your HD & see if the conversion is any faster from there.

[Denny Lajeunesse]

Is indexing turned OFF? If it is on it will seriously hamper your HD and slow transcoding to a crawl.

[Tim Lawrence]

Hi Denny,

How can one tell if indexing is on?

Thanks,

TL

[Stu Holmes]

Originally Posted by Randy Painter

If your not using a scratch disk, then that's your bottleneck. Reading and writing to the same disk will make it crawl. If you haven't purchased one yet, if you can afford it, get a SSD external drive. Or at least get a 7200 rpm hard disk for your external. Pretty sure your internal drive is 5400 rpm's unless you have a SSD drive.

Interestng. OK here's a question : i've got a 5400rpm 500Gb internal drive on my laptop, and a 7200rpm 2Gb externakl drive. Up til now, i've had all editing projects 100% on the external 7200rpm drive. Media files, .veg file, renders too.

What does anyone think would be a more optimum setup? Have all files on the 7200rpm drive but render to the internal 5400rpm drive? I note the "reading and writing to the same drive will slow it to a crawl".

appreciate any comments on this stuff.

cheers