speed and bandwidth questions

[AndrewG]

Hi,

I have some questions about how much power and bandwidth is needed to play the reference .mov files.

If I'm playing the 0.5k reference .mov file, does it still pull the full 4k data over to system memory and then extract 0.5k using the CPU (resulting in 28MB/s bandwidth usage), or does it just pull over the parts it needs? I want to know where does it extract the 0.5k frame, on the CPU or does it just READ the required data straight out of the .r3d file at some offset (resulting in much less bandwidth usage).

Also, does the speed of decoding scale linearly with the size of the frame? So I could decode four 0.5k files in the same time as one 1k image?

Does anyone have any stats on how much CPU power it takes to decode a frame?

Thanks =)

 

[AndrewG]

anyone?

 

[Russell Fogle]

Watch the "Red Mythbusters" video on Red.com They show you some settings in this video for playback quality that allow you to playback 2K Proxie files in real time... if you have enough machine. I watched the video... Made my playback settings the same and it works...

Below is RED's published system requirements...

Recommended configurations for Final Cut Pro 6.0.3
Configuration #1: Intel MacPro or MacBookPro, Leopard (OS 10.5.2) with QuickTime 7.4.5
#2: Intel MacPro or MacBookPro, Tiger (OS 10.4.11) with QuickTime 7.4.5
* users with NVIDIA 7300 GT should update to Leopard
Minimum RAM for all configs: 1 G
Suggested RAM for Kona3 configs on Leopard: 2 GB*
* if experiencing performance issues. If not, AJA recommends 4 GB
RED recommends all users on Tiger or Leopard upgrade to QuickTime 7.4.5

 

[AndrewG]

Thanks for the reference Russel, that video is very useful!

What I'm looking for now is actual bandwidth numbers.. In megabits/bytes per second.

So we know that red raw is 28-38 MB/sec, but what about the QT reference videos?

 

[M Most]

Watch the "Red Mythbusters" video on Red.com They show you some settings in this video for playback quality that allow you to playback 2K Proxie files in real time... if you have enough machine.

I would note that "playback 2K proxies in real time" doesn't necessarily mean what one might think it means. What you can do is play back at that frame size, but with no debayer and at a reduced quality level. 2K real time playback at full quality still requires considerably more horsepower and at the moment can really only be done on a Scratch or ScratchCine system running on a Skulltrail based PC.