script to reduce the image size
This commit is contained in:
Ludger Sicking
parent
163f3585a9
commit
c2139730ae
|
|
@ -0,0 +1,213 @@
|
|||
#!/usr/bin/env bash
|
||||
# Resize/convert all png|PNG|jpeg|jpg|JPG images under content/ to .jpg,
|
||||
# long edge <= MAX_DIM px, file size <= MAX_BYTES, in place.
|
||||
# Exception: PNGs already under PNG_KEEP_MAX_DIM px and PNG_KEEP_MAX_BYTES
|
||||
# bytes are left as PNG, untouched.
|
||||
# Updates filename references in content/**/*.md when a file gets renamed.
|
||||
#
|
||||
# Usage: scripts/resize-and-convert-images.sh [content-dir] --apply
|
||||
# scripts/resize-and-convert-images.sh [content-dir] (dry run, default)
|
||||
#
|
||||
# SAFETY: this script defaults to a dry run and changes NOTHING unless you
|
||||
# pass --apply explicitly. Unknown arguments are a hard error, not silently
|
||||
# ignored, so a typo can never turn a dry run into a real run.
|
||||
set -uo pipefail
|
||||
|
||||
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
|
||||
CONTENT_DIR="$SCRIPT_DIR/../content"
|
||||
MAX_DIM=1600
|
||||
MAX_BYTES=307200 # 300 KiB
|
||||
PNG_KEEP_MAX_DIM=1600
|
||||
PNG_KEEP_MAX_BYTES=204800 # 200 KiB
|
||||
DRY_RUN=1
|
||||
CONTENT_DIR_SET=0
|
||||
|
||||
usage() {
|
||||
echo "Usage: $0 [content-dir] --apply" >&2
|
||||
echo " $0 [content-dir] # dry run (default, no changes written)" >&2
|
||||
}
|
||||
|
||||
for arg in "$@"; do
|
||||
case "$arg" in
|
||||
--apply) DRY_RUN=0 ;;
|
||||
--dry-run) DRY_RUN=1 ;;
|
||||
--help|-h) usage; exit 0 ;;
|
||||
-*)
|
||||
echo "Error: unknown option '$arg'" >&2
|
||||
usage
|
||||
exit 1
|
||||
;;
|
||||
*)
|
||||
if [ "$CONTENT_DIR_SET" -eq 1 ]; then
|
||||
echo "Error: unexpected extra argument '$arg'" >&2
|
||||
usage
|
||||
exit 1
|
||||
fi
|
||||
CONTENT_DIR="$arg"
|
||||
CONTENT_DIR_SET=1
|
||||
;;
|
||||
esac
|
||||
done
|
||||
|
||||
if ! command -v convert >/dev/null 2>&1; then
|
||||
echo "Error: ImageMagick 'convert' not found." >&2
|
||||
exit 1
|
||||
fi
|
||||
if ! command -v identify >/dev/null 2>&1; then
|
||||
echo "Error: ImageMagick 'identify' not found." >&2
|
||||
exit 1
|
||||
fi
|
||||
if [ ! -d "$CONTENT_DIR" ]; then
|
||||
echo "Error: content dir '$CONTENT_DIR' not found." >&2
|
||||
exit 1
|
||||
fi
|
||||
|
||||
converted=0
|
||||
renamed_only=0
|
||||
skipped_ok=0
|
||||
skipped_png_small=0
|
||||
skipped_collision=0
|
||||
still_too_big=0
|
||||
errors=0
|
||||
|
||||
mapfile -d '' files < <(find "$CONTENT_DIR" -type f \
|
||||
\( -name '*.png' -o -name '*.PNG' -o -name '*.jpeg' -o -name '*.jpg' -o -name '*.JPG' \) -print0 | sort -z)
|
||||
|
||||
total=${#files[@]}
|
||||
echo "Found $total image(s) under $CONTENT_DIR"
|
||||
[ "$DRY_RUN" -eq 1 ] && echo "(dry run — no files will be changed)"
|
||||
echo
|
||||
|
||||
update_refs() {
|
||||
# $1 old basename, $2 new basename, $3 directory to search (content root)
|
||||
local old="$1" new="$2" root="$3"
|
||||
grep -rlF -- "$old" "$root" --include='*.md' 2>/dev/null | while IFS= read -r mdfile; do
|
||||
OLD="$old" NEW="$new" perl -i -pe 's/\Q$ENV{OLD}\E/$ENV{NEW}/g' "$mdfile"
|
||||
echo " updated reference in $mdfile"
|
||||
done
|
||||
}
|
||||
|
||||
i=0
|
||||
for src in "${files[@]}"; do
|
||||
i=$((i+1))
|
||||
dir=$(dirname "$src")
|
||||
base=$(basename "$src")
|
||||
stem="${base%.*}"
|
||||
ext="${base##*.}"
|
||||
target="$dir/$stem.jpg"
|
||||
|
||||
printf '[%d/%d] %s\n' "$i" "$total" "$src"
|
||||
|
||||
fmt=""
|
||||
if [ "$ext" = "png" ] || [ "$ext" = "PNG" ]; then
|
||||
w=$(identify -format '%w' "$src" 2>/dev/null)
|
||||
h=$(identify -format '%h' "$src" 2>/dev/null)
|
||||
size=$(stat -c%s "$src")
|
||||
longedge=$(( w > h ? w : h ))
|
||||
if [ "$longedge" -lt "$PNG_KEEP_MAX_DIM" ] && [ "$size" -lt "$PNG_KEEP_MAX_BYTES" ]; then
|
||||
echo " small PNG (${w}x${h}, ${size} bytes) below keep-as-is threshold, leaving untouched"
|
||||
skipped_png_small=$((skipped_png_small+1))
|
||||
continue
|
||||
fi
|
||||
else
|
||||
fmt=$(identify -format '%m' "$src" 2>/dev/null | head -c4)
|
||||
fi
|
||||
|
||||
if [ "$fmt" = "JPEG" ]; then
|
||||
w=$(identify -format '%w' "$src" 2>/dev/null)
|
||||
h=$(identify -format '%h' "$src" 2>/dev/null)
|
||||
size=$(stat -c%s "$src")
|
||||
longedge=$(( w > h ? w : h ))
|
||||
if [ "$longedge" -le "$MAX_DIM" ] && [ "$size" -le "$MAX_BYTES" ]; then
|
||||
if [ "$target" = "$src" ]; then
|
||||
echo " already compliant, skipping"
|
||||
skipped_ok=$((skipped_ok+1))
|
||||
else
|
||||
if [ -e "$target" ]; then
|
||||
echo " COLLISION: target '$target' already exists — skipping, needs manual review" >&2
|
||||
skipped_collision=$((skipped_collision+1))
|
||||
elif [ "$DRY_RUN" -eq 1 ]; then
|
||||
echo " would rename (no re-encode needed) -> $target"
|
||||
else
|
||||
mv -f "$src" "$target"
|
||||
update_refs "$base" "$stem.jpg" "$CONTENT_DIR"
|
||||
renamed_only=$((renamed_only+1))
|
||||
echo " renamed (already compliant) -> $target"
|
||||
fi
|
||||
fi
|
||||
continue
|
||||
fi
|
||||
fi
|
||||
|
||||
if [ "$target" != "$src" ] && [ -e "$target" ]; then
|
||||
echo " COLLISION: target '$target' already exists — skipping, needs manual review" >&2
|
||||
skipped_collision=$((skipped_collision+1))
|
||||
continue
|
||||
fi
|
||||
|
||||
if [ "$DRY_RUN" -eq 1 ]; then
|
||||
echo " would convert -> $target"
|
||||
continue
|
||||
fi
|
||||
|
||||
tmp=$(mktemp --suffix=.jpg "${dir}/.rsz-XXXXXX")
|
||||
|
||||
quality=85
|
||||
dim=$MAX_DIM
|
||||
status=0
|
||||
while :; do
|
||||
if ! err=$(convert "$src" -auto-orient -background white -alpha remove -alpha off \
|
||||
-resize "${dim}x${dim}>" -strip -sampling-factor 4:2:0 -quality "$quality" "$tmp" 2>&1); then
|
||||
echo " ERROR converting $src: $err" >&2
|
||||
rm -f "$tmp"
|
||||
status=-1
|
||||
break
|
||||
fi
|
||||
size=$(stat -c%s "$tmp")
|
||||
if [ "$size" -le "$MAX_BYTES" ]; then
|
||||
status=1
|
||||
break
|
||||
fi
|
||||
if [ "$quality" -gt 40 ]; then
|
||||
quality=$((quality-5))
|
||||
continue
|
||||
fi
|
||||
if [ "$dim" -gt 800 ]; then
|
||||
dim=$((dim-160))
|
||||
quality=70
|
||||
continue
|
||||
fi
|
||||
status=2
|
||||
break
|
||||
done
|
||||
|
||||
if [ "$status" -eq -1 ]; then
|
||||
errors=$((errors+1))
|
||||
continue
|
||||
fi
|
||||
|
||||
if [ "$status" -eq 2 ]; then
|
||||
finalsize=$(stat -c%s "$tmp")
|
||||
echo " WARNING: could not get under $MAX_BYTES bytes (final ${finalsize} bytes, quality=$quality, dim=$dim)" >&2
|
||||
still_too_big=$((still_too_big+1))
|
||||
fi
|
||||
|
||||
mv -f "$tmp" "$target"
|
||||
converted=$((converted+1))
|
||||
echo " converted -> $target ($(stat -c%s "$target") bytes)"
|
||||
|
||||
if [ "$target" != "$src" ]; then
|
||||
rm -f "$src"
|
||||
update_refs "$base" "$stem.jpg" "$CONTENT_DIR"
|
||||
fi
|
||||
done
|
||||
|
||||
echo
|
||||
echo "Done."
|
||||
echo " converted (re-encoded): $converted"
|
||||
echo " renamed only (already compliant): $renamed_only"
|
||||
echo " already compliant, untouched: $skipped_ok"
|
||||
echo " small PNGs kept as-is: $skipped_png_small"
|
||||
echo " skipped due to name collision: $skipped_collision"
|
||||
echo " still over size limit after max compression: $still_too_big"
|
||||
echo " errors: $errors"
|
||||
Loading…
Reference in New Issue