Speeding Up Bitlevel Noodling

Howdy!

I'm a NodeBox noob. For fun, I'm trying to recreate Jared Tarbell's substrate processing sketch in NodeBox. Using the CoreImage module, the code transliteration is pretty straightforward. However, the result is painfully slow.

My guess, as suggested by the CoreImage docs, is that layer.set_pixel is pretty slow. Are there any suggestions for batching up a bunch of bit manipulations and blasting them to a layer all at once? Or alternative, faster ways to do bit level manipulations in NodeBox? I know this isn't supposed to be NodeBox's forte', but I'm hoping there's a common technique that I'm missing.

Thanks in advance!

This is the fastest way that I know of (thanks to Duane Bailey's post). It uses a Numeric array to store pixel values between 0 and 255, and NSBitmapImageRep to create a TIFF byte string which you can then pass to the image() command:

from AppKit import NSBitmapImageRep, NSDeviceRGBColorSpace
from Numeric import array
 
width, height = 400, 400
 
pixels = array([0] * width * height * 4, typecode='c')
for i in range(len(pixels)/4):
    pixels[i*4+0] = random(255) # R
    pixels[i*4+1] = random(255) # G
    pixels[i*4+2] = random(255) # B
    pixels[i*4+3] = 255         # A
    
pixels = (pixels, None, None, None, None)
img = NSBitmapImageRep.alloc().initWithBitmapDataPlanes_pixelsWide_pixelsHigh_bitsPerSample_samplesPerPixel_hasAlpha_isPlanar_colorSpaceName_bytesPerRow_bitsPerPixel_(
    pixels, width, height, 8, 4, True, False, NSDeviceRGBColorSpace, width * 4, 32
)
 
bytes = img.TIFFRepresentation()
image(None, 0, 0, data=bytes)