HD Syphon stream

[colinyell]

Hi,

I have recently bought a copy of mad mapper because of its ability to accept a syphon input from quartz composer. However on testing recently I have found that if I try to play a HD video on a billboard in quartz and syphon it to mad mapper the video instantly becomes choppy and unusable.

Before I activate the syphon input the video is fine and smooth but as soon as I send through a 1920 x 1080 image the problems start.

Any ideas how I can improve the quality?

I’m using a brand new 8 core mac pro with two ATI 5770 graphics cards and I have even tried playing the video from a ram disk.

I have tried building an app so I’m not even running quartz composer and I still get the same issues any help would be greatly appreciated.

Cheers,

Colin

[vade]

HD video playback is totally doable. However, there are a few things you need to ensure you do in Quartz Composer (if you want to use that) for HD playback via Syphon.

#1) With the Apple Movie Importer patch, ensure you use Asynchronous mode (select the Movie Importer patch in the editor, hit Apple – 2, to get to settings, and enable the check box).

That ensures that the Movie playback is buffered and reads ahead of time, rather than “just in time”.

#2) What codec are you using? What frame rate movie?

#3) Are you using the QC Syphon Server (Public release 2) with the Image Input , or are you capturing the scene?

#4) Are you running Quartz Composer editor in 32, or 64 bit mode? Due to some nuances in Quicktime, 32 bit mode will be faster for movie playback and VRam usage. To do this get info on the Quartz Composer.app, and select “Open in 32 bit”.

Let us know.

[vade]

Oh. Wait.

You are using *TWO* GPUs eh?

Do you have QC rendering in 1, and the other running Mad Mapper?

Try using two displays on a single GPU. You will avoid expensive read back from one GPU to the other.

[colinyell]

Thanks Vade,

What you are saying makes a lot of sense. I will give it a try tomorrow and let you know.

Cheers,

Colin

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