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View Full Version : Not getting realtime transcodes on batch export



Michael Totten
11-08-2009, 07:49 AM
I just installed the rocket recently, so maybe I'm overlooking something obvious here.

I spent the better part of yesterday grading/transcoding in rocketCine-x... I did three batch exports (anywhere from 50-125 clips at a time).

Export Presets:
1920X1080 23.98
Apple ProRes HQ

It's hard to say exactly how slow it's going but I would say it's taking roughly twice as long (perhaps more). Could it be that the R3D's files and the export folder are on different external FW800 Drives? I would think those drives could handle this kind of bandwidth and the Mac bus should be ok, no ?

thanks. Any insight would be appreciated.

Mike Prevette
11-08-2009, 08:02 AM
Well ProRes and the Quicktime overhead slow it down a bit. The way I understand it RedRocket just does the debayer, then the CPU does any format encoding that needs to happen (alla turn raw rgb info into prores) Try encoding to tiffs or DPX's and It'll be a little bit faster.

But the real slow down is going to be those firewire 800 drives. On some macs if 2 fw800 drives are on the same bus it divides the bandwidth of the port in half, to basically FW400 speeds. Try writing to an internal drive or RAID.

Michael Totten
11-08-2009, 08:06 AM
Well ProRes and the Quicktime overhead slow it down a bit. The way I understand it RedRocket just does the debayer, then the CPU does any format encoding that needs to happen (alla turn raw rgb info into prores) Try encoding to tiffs or DPX's and It'll be a little bit faster.

But the real slow down is going to be those firewire 800 drives. On some macs if 2 fw800 drives are on the same bus it divides the bandwidth of the port in half, to basically FW400 speeds. Try writing to an internal drive or RAID.

I may be wrong but I'm pretty sure that Jim mentioned the rocket was doing realtime encode to Apple Pro-ResHQ (can anyone verify this) ?

Mike I'm going to do a test to a few different drives. I'm sure the FW800 bottleneck on the same bus is part of the equation... but I'm really hoping once I remedy that I can expect realtime encodes to pro-res.

Kaku Ito
11-08-2009, 08:56 AM
Codec like ProRes requires some CPU power to compress, so I'd say it takes little longer than realtime. With fast enough storage then DPX will render realtime, maybe uncompress QT would be not so slow neither.

Gabriele Turchi
11-08-2009, 09:01 AM
Guys does anyone have a number of fps encoding ProRes HD aon the latest MacPro?...

I actually asked several times in severals thread but nobody that have the rocket seems answer...

so how many FPS encoding ProRes HQ 23.98 on a dual cpu latest macpro???

if there is no fps speed render info in redcinex ,please try a 3 minute clip and see how it takes...
Thanks a lot



g

Michael Totten
11-08-2009, 10:33 AM
Guys does anyone have a number of fps encoding ProRes HD aon the latest MacPro?...

I actually asked several times in severals thread but nobody that have the rocket seems answer...

so how many FPS encoding ProRes HQ 23.98 on a dual cpu latest macpro???

if there is no fps speed render info in redcinex ,please try a 3 minute clip and see how it takes...
Thanks a lot



g

I have the latest 2.26 MacPro with a 4870 ATI graphics card & 16GB RAM. I'll try and do a test later this afternoon. I'm wondering if those Intel X-25 raided solid state drives would speed things up ? anyone have them installed in their system?

MichaelP
11-08-2009, 11:15 AM
I can't speak for actual transcode rates, but on the same system, same drives, same files, transcoding to Apple ProRes is about 50% slower than Avid DNxHD when using the REDROCKET. I am sure the efficiency of encode times is a factor relatively speaking. In all cases, the hard drives will be a bottleneck. I am using a 16TB RAID 0.

Michael

Gabriele Turchi
11-08-2009, 11:23 AM
Guys if you use 1 drive to read the r3d and 1 drive to write it's enough...
R3d it's 36MB/sec and prores less than that...
A normal hard drive sustain 50/MBsec...
Use a raid it's always suggested but not essential..

G

Frank Cueto
11-08-2009, 11:55 AM
Would going to ProRes NON-HQ be faster than with HQ? Does resolution make it slower, or the burn-ins? How about including audio?

I have to start transcoding about 4-6 hours of material per day soon.....

Frank Cueto
11-27-2009, 08:22 PM
*BUMP*

Uli Plank
11-28-2009, 01:05 AM
No difference in CPU load between HQ or SQ, but burn-ins slow it down a bit. If it's for offline, give DVCPro HD a try.