asc-screenshot-resize

$2b

Common current device-type anchors:

• IPHONE_65 for the common 6.5-inch iPhone screenshot set.

• IPAD_PRO_3GEN_129 for the common 12.9/13-inch iPad screenshot set.

Run asc screenshots sizes --all when targeting other display types such as 6.9-inch iPhone, Apple TV, Mac, Vision Pro, iMessage, or Watch.

Workflow

1. Sanitize filenames

macOS screenshots can contain hidden Unicode spaces that make tools fail with "not a valid file". Sanitize before batch work:

python3 -c "

import os

for f in os.listdir('.'):

    clean = f.replace('\u202f', ' ')

    if f != clean:

        os.rename(f, clean)

        print(f'Renamed: {clean}')

"

2. Inspect dimensions and metadata

sips -g pixelWidth -g pixelHeight screenshot.png

sips -g hasAlpha -g space screenshot.png

App Store Connect rejects screenshots with alpha transparency. Strip alpha by round-tripping through JPEG:

sips -s format jpeg input.png --out /tmp/asc-screenshot-no-alpha.jpg

sips -s format png /tmp/asc-screenshot-no-alpha.jpg --out output.png

rm /tmp/asc-screenshot-no-alpha.jpg

Batch-strip alpha from PNGs:

for f in *.png; do

  if sips -g hasAlpha "$f" | grep -q "yes"; then

    sips -s format jpeg "$f" --out /tmp/asc-screenshot-no-alpha.jpg

    sips -s format png /tmp/asc-screenshot-no-alpha.jpg --out "$f"

    rm /tmp/asc-screenshot-no-alpha.jpg

    echo "Stripped alpha: $f"

  fi

done

3. Resize only after choosing a target from asc

Pick a width and height from asc screenshots sizes --all. sips -z takes height first, then width:

# Example: portrait IPHONE_65 1284 x 2778

sips -z 2778 1284 input.png --out output.png

Batch resize to a chosen target:

mkdir -p resized

for f in *.png; do

  sips -z 2778 1284 "$f" --out "resized/$f"

done

4. Validate outputs with asc

sips -g pixelWidth -g pixelHeight -g hasAlpha resized/*.png

asc screenshots validate --path "./resized" --device-type "IPHONE_65" --output table

5. Upload only after validation

asc screenshots upload --version-localization "LOC_ID" --path "./resized" --device-type "IPHONE_65" --dry-run --output table

asc screenshots upload --version-localization "LOC_ID" --path "./resized" --device-type "IPHONE_65"

Guardrails

• Treat asc screenshots sizes --all as authoritative; Apple size requirements change.

• Do not stretch screenshots across incompatible aspect ratios unless the user accepts the visual tradeoff.

• Always output to a separate file or directory to preserve originals.

• Screenshots must be PNG or JPEG and must not include alpha transparency.

• Convert Display P3 or other color spaces to sRGB when needed:

sips -m "/System/Library/ColorSync/Profiles/sRGB IEC61966-2.1.icc" input.png --out output.png

• Prefer asc screenshots validate over visual inspection before upload.