Greyscale ImageBuffer

M.Oostrik's picture

Hi All

I'm using the queue patch to create a video buffer. For most of my installations I use black and white (infrared) video from my flea2. The dimensions of the video are 1280x960 and it runs @ 30 fps.

When I use the image as is I can store up to 1000 images before strange things start to happen (flickering frame drops etc). I quess because most of the video Ram is used (?).

Because I use black and white video it din't seem logical to use the image as is in QC, because the image is RGBA (is this right?).

I started looking into alternatives and decided to try out the QC image to CV image (from Kineme CV) before the queue patch and CV to QC after. This resulted in a stunning amount of 20.000 images before QC fps start to fall under 30. Up to 35.000 (and counting while i write) images it runs @ 20 fps.

I got one problem here. The image turns from Black and White into Blue and White. I can solve this by inserting a Render in Image patch or an Image Resizer patch after the Video in patch or try to restore the black and white with a False Color patch. All these solutions bring down fps by around 30% .

2 concrete questions. is there a solution for the blue problem? anybody got suggestions for a different method of converting the images to greyscale?

I'll try the same patch on my Hackintosh with a GTS 250 graphics card when i find the max images on my MacPro with Ati Radeon X1900.

regards Matthias

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M.Oostrik's picture
Re: Greyscale ImageBuffer

after 40.000 images fps starts to fall to 15, but no irregularities

by the way the Color Coding of the Flea2 is set to Mono8

attached the composition i use for testing the buffer

Grayscale Buffer.qtz7.72 KB

M.Oostrik's picture
Re: Greyscale ImageBuffer

after 50.000 frames i started to mess around and the composition crashed. Looking at the Activity Monitor I started to wonder if the CV image is stored in the video RAM at all, because the Real Memory was rising slowly but steadily.

For that sake is the normal QC Image in the Queue object in the Video Ram? How can i check this?

M.Oostrik's picture
Re: Greyscale ImageBuffer

haha, back to square one

Doing some more testing I found out the all members of the queue show the same image. Changing the index results in a crash.

Back to my original question:

(How) can i create a grayscale image in QC?