unpack() exploration!

[Marlin Rowley]

All:

I've got a script that runs really slow because I'm reading from a stream a byte at a time:

// TERRIBLE
for y in range( height ):
        for color in range(4):
            for x in range( width ):
                    pixelComponent = fileIO.read(4)
                    buffer = unpack("!f",pixelComponent)  << unpacks ONE float, but we now can do something with that pixel component.


I can speed this up dramatically if I did this:

// MUCH FASTER
for y in range( height ):
    for color in range(4):
        pixelComponent = fileIO.read(4*width) <<<<<<<<<  GET a LOT more data from the stream into memory FIRST!!
        for x in range( width ):
           buffer = unpack( ?????? ) <<<< how do I get each float from the pixelComponent???


-M



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