Skip to content

Screenshots: bring iOS 27's 16-bit P3 screenshots down to 8 bits #284

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
renrenmimi merged 1 commit into from
Oct 2, 2026
Merged

Screenshots: bring iOS 27's 16-bit P3 screenshots down to 8 bits #284

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
20 changes: 13 additions & 7 deletions ios-native/scripts/device-screenshot.sh
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -54,14 +54,20 @@ fi

xcrun devicectl device capture screenshot --device "$UDID" --destination "$OUT" >/dev/null

# Device screenshots are 16-bit and the pixel reader needs 8. sips refuses the
# conversion on a file that is already 8-bit, which is a success for our
# purposes, so its exit code is not a failure here.
DEPTH=$(sips -g bitsPerSample "$OUT" 2>/dev/null | awk -F': ' '/bitsPerSample/ {print $2}')
if [ "${DEPTH:-16}" != "8" ]; then
sips -s format png --setProperty bitsPerSample 8 "$OUT" --out "$OUT" >/dev/null 2>&1 || {
# Device screenshots are 16-bit and the pixel reader needs 8. On an iOS 27
# screenshot (16-bit Display P3), `sips --setProperty bitsPerSample 8` writes
# nothing and still exits 0, so sips's exit code says nothing either way.
# Matching the image to its own colour profile writes it at 8 bits without
# changing its colours; the depth is read back to know whether that worked.
depth() { sips -g bitsPerSample "$1" 2>/dev/null | awk -F': ' '/bitsPerSample/ {print $2}'; }
if [ "$(depth "$OUT")" != "8" ]; then
PROFILE=$(sips -g profile "$OUT" 2>/dev/null | awk -F': ' '/profile/ {print $2}')
ICC="/System/Library/ColorSync/Profiles/${PROFILE}.icc"
[ -n "$PROFILE" ] && [ -f "$ICC" ] || ICC="/System/Library/ColorSync/Profiles/Display P3.icc"
sips --matchTo "$ICC" "$OUT" --out "$OUT" >/dev/null 2>&1 || true
if [ "$(depth "$OUT")" != "8" ]; then
echo "Could not reduce $OUT to 8-bit; sample-pixels.py will say so." >&2
}
fi
fi

echo "wrote $OUT"
Expand Down
Loading