def normalizeWeights(pixelExpr): maxSum = max( sum(weights) for expr in pixelExpr for weights in expr ) return [ [ scaleWeights(weights, maxSum) for weights in expr ] for expr in pixelExpr ]
def convertExpr4to2(case, expr4):
weights2 = [0] * 4
for weights4 in expr4:
for neighbour, weight in enumerate(scaleWeights(weights4, 256)):
weights2[neighbour] += weight
weights2 = simplifyWeights(weights2)
if ((case >> 4) & 15) in (2, 6, 8, 12):
assert sorted(weights2) == [0, 2, 7, 23]
weightMap = { 0: 0, 2: 1, 7: 1, 23: 2 }
elif ((case >> 4) & 15) in (0, 1, 4, 5):
assert sorted(weights2) == [0, 3, 3, 10]
weightMap = { 0: 0, 3: 1, 10: 2 }
else:
weightMap = None
if weightMap:
weights2 = tuple(weightMap[weight] for weight in weights2)
return [weights2]
for qx in range(quadrantWidth)
]
for expr in [[expr[subPixel] for subPixel in quadrantMap]
for expr in pixelExpr]:
for weights in expr:
for neighbour in (2, 5, 6, 7, 8):
assert weights[neighbour] == 0, weights
return [[
extractTopLeftWeights(expr[subPixel]) for subPixel in quadrantMap
] for expr in pixelExpr]
def convertExpr4to2(case, expr4):
weights2 = [0] * 4
for weights4 in expr4:
for neighbour, weight in enumerate(scaleWeights(weights4, 256)):
weights2[neighbour] += weight
weights2 = simplifyWeights(weights2)
if ((case >> 4) & 15) in (2, 6, 8, 12):
assert sorted(weights2) == [0, 2, 7, 23]
weightMap = {0: 0, 2: 1, 7: 1, 23: 2}
elif ((case >> 4) & 15) in (0, 1, 4, 5):
assert sorted(weights2) == [0, 3, 3, 10]
weightMap = {0: 0, 3: 1, 10: 2}
else:
weightMap = None
if weightMap:
weights2 = tuple(weightMap[weight] for weight in weights2)
return [weights2]
