# ICO→PNG original sample study

Original experiment date: 2026-10-25. CC0 synthetic artwork. No third-party logos.
1. Open https://filepetal.com/ico-to-png/ . Select multi-size.ico and the image number listed in verification.json. Convert and save the offered PNG. Repeat for each image and the other source ICOs.
2. Inspect the downloaded picture, native dimensions and transparent regions. No enlargement or background removal is performed. The two same-size entries contain different artwork.
3. Read verification.json for exact input/output bytes, dimensions, SHA-256, selected image number, alpha values and independent Pillow comparison. The six diagnostic inputs should show an error and no stale/partial download.
4. Run `python inspect-downloads.py` to check these saved reference files (requires Pillow). Run generate-fixtures.py in an empty folder to regenerate the inputs. Pillow versions may change compressed bytes. Reference hashes identify exact recorded downloads, not a universal encoding guarantee.

Scope: one desktop in-app browser and original synthetic files. Partly transparent colors may be rounded by browser canvas processing. No all-format color fidelity, physical-phone, Windows shell, competitor conversion or batch support claimed. The live converter handles one selected contained image at a time.