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Workflows
Coding workflows · PNG Paeth prediction
03
A concrete starting point
Choose the PNG Paeth predictor from left, above and upper-left byte values. Test tied distances and channel extremes, favoring left then above on ties and rejecting non-byte integers or Boolean inputs.
Define the change
Describe the input, expected output and boundaries that must stay intact.
Inspect the work
Review the proposed edits and any commands before relying on their result.
Check the outcome
Compare actual behavior with the expected result. If a check fails, investigate it before applying more changes.
PNG Paeth prediction
A concrete starting point
def paeth(left, above, upper_left):
if any(type(v) is not int or not 0 <= v <= 255
for v in (left, above, upper_left)):
raise ValueError("byte integers required")
p = left + above - upper_left
dl, da, dc = abs(p-left), abs(p-above), abs(p-upper_left)
if dl <= da and dl <= dc: return left
if da <= dc: return above
return upper_leftThe example is a starting point for a real project, not a claim that generated code is already tested. Adjust paths, dependencies and expected behavior to match your application.