forensicsProeasy
Блендер (Blender)
bug-makers
Task: a palette PNG that file(1) reports as valid but Pillow refuses to open with 'broken data stream'. Solution: identify that the IDAT chunks were shuffled, brute-force the permutation by anchoring the chunk that starts with the zlib header (78 da), validate via exact decompressed length, manually de-filter scanlines, and decode the recovered QR code.
$ ls tags/ techniques/
png_chunk_analysisidat_chunk_reorderingzlib_stream_reconstructionzlib_header_identificationmanual_png_defilteringqr_code_decoding
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