gistfile1.py

import random
import struct

def random_padded( blockSize, percent ):
    result = []

    numRandom = percent * blockSize / 100
    for x in xrange( numRandom ):
        result.append( random.randint( 0, 255 ) )
    
    for x in xrange( blockSize - numRandom ):
        result.append( 0 )

    return result

def random_reduced( blockSize, percent ):
    result = []
    
    maxVal = 255 * percent / 100
    for x in xrange( blockSize ):
        result.append( random.randint( 0, maxVal ) )

    return result

def random_repeated( blockSize, percent ):
    result = []
                
    if percent == 0:
        numCopies = blockSize - 1
    else:
        numCopies = 100.0 / percent - 1.0

    numCopies += 1

    intCopies = int( numCopies )
    fracCopies = numCopies - intCopies

    while len(result) < blockSize:
        val = random.randint( 0, 255 )
        result.append( val )
        for x in xrange( intCopies ):
            result.append( val )
        if ( random.uniform( 0.0, 1.0 ) < fracCopies ):
            result.append( val )

    return result[0:blockSize]

def writeArrayAsBlock( fileName, block ):
    f = open( fileName, "wb" )
    f.write( bytearray( block ) )
    f.close()

def main():
    for p in [0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100]:
        writeArrayAsBlock( "padded-%03d.block" % ( p ),
                           random_padded( 8192, p ) )
        writeArrayAsBlock( "reduced-%03d.block" % ( p ),
                           random_reduced( 8192, p ) )
        writeArrayAsBlock( "repeated-%03d.block" % ( p ),
                           random_repeated( 8192, p ) )

if __name__ == "__main__":
    main()