Strip PNG metadata to ensure deterministic screenshot output#1
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EmilioBejasa wants to merge 1 commit intoscreenshotbot:mainfrom
Open
Strip PNG metadata to ensure deterministic screenshot output#1EmilioBejasa wants to merge 1 commit intoscreenshotbot:mainfrom
EmilioBejasa wants to merge 1 commit intoscreenshotbot:mainfrom
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Android's Bitmap.compress() adds metadata chunks (like tIME timestamps) to PNG files. This causes byte-level differences between otherwise identical screenshots, breaking hash-based comparison in Screenshotbot. This change adds a PngMetadataStripper utility that removes non-essential PNG chunks while preserving image data and essential color information. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
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Summary
PngMetadataStripperutility to remove non-essential PNG chunksAlbumImpl.writeBitmap()to strip metadata before savingProblem
Android's
Bitmap.compress()adds metadata chunks liketIME(timestamps) to PNG files. This causes byte-level differences between otherwise identical screenshots, which breaks hash-based comparison in Screenshotbot.When screenshots are visually identical but have different timestamps, Screenshotbot flags them as changed and requires manual approval.
Solution
Strip non-essential PNG chunks (tIME, tEXt, iTXt, etc.) while preserving essential image data (IHDR, IDAT, PLTE, IEND, etc.).
Test plan
🤖 Generated with Claude Code