Status: 

Vuo version: 

OS version: 

  • OS X 10.9

How severely does this bug affect you?: 

●●●○ — It prevents me from completing a specific task with Vuo.

Steps causing the bug to occur: 

  1. Generate a prores 4444 12 bit video file
  2. Video output information of Decode Movie Image & Play Movie show 8 bit not 12 bit or 16 bit

Screenshots: 

Comments

I noticed this became a

alexmitchellmus's picture
Submitted by

I noticed this became a problem for me when using feedback image with 4444 prores with alpha channel. The 8 bit values caused banding within the feedback image (even when feedback is set to 16 bit). The content that is 4444 prores was captured at 10bit with a shogun recorder out of a GH4 (so it is real 10 bit at least). I can post an example soon.

I also completed a test with greyscale gradient generator within Vuo with feedback and there wasn't any banding.

UPDATE: After more research the banding may not be due to 8 bit Video file playback. I will investigate further.

It would be good if the decode movie nodes could have an 8 or 16 bit toggle.

Yeah, we do plan to provide

jstrecker's picture
Submitted by

Yeah, we do plan to provide an option to switch between 8 or 16 bpc — or "automatic", the default.

In preliminary testing (thanks for the link to documentation you emailed), AVFoundation was only able to provide the 16bpc image on CPU, not as an OpenGL texture, so we expect 8bpc to have noticeably better performance/framerates. The toggle would allow the composition author to choose their quality/performance tradeoff.

@Azy @Jaymie for highspeed

alexmitchellmus's picture
Submitted by

Azy @jaymie for highspeed video decoding HAP codec is really the only way to do that currently. Prores isn't really designed for realtime video systems.

Azy if you want HAP check out my FR.

HAP also allows alpha channel as well, and the video data is decoded completely on the GPU! :-)