question about PNG image format the lossless data compression -

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if take simple bitmap ( image without compression ) , compress png format , extract original bitmap - same image ?

because first step of png compression pre-compression => filtering ( prediction current pixel according the pixel before ) on original bitmap - , mean after image not same if extract after compression.

png uses lossless compression, answer yes, same data after decompressing. filtering stuff not lose information, it’s preprocessing stage yield better compression ratios common sample patterns (like constant color lines or gradients).


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