size reduction images

scripts/README_IMAGE_COMPRESSION.md

@@ -30,7 +30,8 @@ pictures/
 
 ### Performance Benefits
 - **60-80% smaller file sizes** for layout browsing
-- **Faster page loads** with compressed images
+- **Additional 75% size reduction** from 50% resize for preview images
+- **Faster page loads** with compressed and resized images
 - **Full quality** maintained for detailed viewing
 - **Progressive enhancement** with WebP support detection
 
@@ -47,12 +48,14 @@ Run the provided script to convert all existing images:
 For individual files:
 
 ```bash
-cwebp -q 75 -m 6 pictures/1771-42-166.jpg -o pictures/1771-42-166-preview.webp
+# The script automatically calculates 50% dimensions
+cwebp -q 75 -m 6 -resize 1200 800 pictures/1771-42-166.jpg -o pictures/1771-42-166-preview.webp
 ```
 
 ### Quality Settings
 - **Quality**: 75% (good balance for text-heavy images)
 - **Compression**: Level 6 (maximum compression)
+- **Resize**: 50% (reduces file size by ~75% additionally)
 - **Format**: WebP (excellent text preservation)
 
 ## Browser Support
@@ -72,11 +75,11 @@ cwebp -q 75 -m 6 pictures/1771-42-166.jpg -o pictures/1771-42-166-preview.webp
 
 Typical compression results for newspaper images:
 
-| Image Type | Original JPEG | WebP Preview | Savings |
-|------------|---------------|--------------|---------|
-| Text page  | 800 KB        | 320 KB       | 60%     |
-| Mixed page | 1.2 MB        | 480 KB       | 60%     |
-| Image page | 1.5 MB        | 750 KB       | 50%     |
+| Image Type | Original JPEG | WebP Preview (50% + compression) | Total Savings |
+|------------|---------------|----------------------------------|---------------|
+| Text page  | 800 KB        | 80 KB                           | 90%           |
+| Mixed page | 1.2 MB        | 120 KB                          | 90%           |
+| Image page | 1.5 MB        | 190 KB                          | 87%           |
 
 ## Development Notes
 

scripts/generate_webp_originals.sh

@@ -2,6 +2,7 @@
 
 # Script to generate high-quality WebP versions of original JPEG files
 # These will be used for the single page viewer (enlarged view)
+# Overwrites existing WebP files for fresh conversion
 # Usage: ./scripts/generate_webp_originals.sh
 
 # Colors for output
@@ -56,10 +57,9 @@ process_file() {
     name_no_ext="${filename%.*}"
     webp_file="$dir/${name_no_ext}.webp"
 
-    # Skip if WebP original already exists and is newer than source
-    if [ -f "$webp_file" ] && [ "$webp_file" -nt "$jpg_file" ]; then
-        echo -e "${YELLOW}Skipping $jpg_file (WebP exists and is newer)${NC}"
-        return 0
+    # Check if WebP original already exists
+    if [ -f "$webp_file" ]; then
+        echo -e "${YELLOW}Overriding existing WebP: $webp_file${NC}"
     fi
 
     # Convert to high-quality WebP

scripts/generate_webp_previews.sh

@@ -1,6 +1,7 @@
 #!/bin/bash
 
 # Script to generate WebP preview images from existing JPEG files
+# Resizes images to 50% and applies high compression for fast layout loading
 # Usage: ./scripts/generate_webp_previews.sh
 
 # Colors for output
@@ -23,6 +24,15 @@ if ! command -v cwebp &> /dev/null; then
     exit 1
 fi
 
+# Check if ImageMagick identify is installed (for resizing)
+if ! command -v identify &> /dev/null; then
+    echo -e "${YELLOW}Warning: ImageMagick identify not found. Resizing will be skipped.${NC}"
+    echo "  Ubuntu/Debian: sudo apt-get install imagemagick"
+    echo "  macOS: brew install imagemagick"
+    echo "  CentOS/RHEL: sudo yum install ImageMagick"
+    echo ""
+fi
+
 # Check if pictures directory exists
 if [ ! -d "$PICTURES_DIR" ]; then
     echo -e "${RED}Error: Pictures directory '$PICTURES_DIR' not found${NC}"
@@ -32,6 +42,7 @@ fi
 echo -e "${GREEN}Generating WebP preview images...${NC}"
 echo "Quality: $QUALITY%"
 echo "Compression: $COMPRESSION"
+echo "Resize: 50% (for faster loading)"
 echo ""
 
 # Counters
@@ -54,16 +65,28 @@ process_file() {
     name_no_ext="${filename%.*}"
     webp_file="$dir/${name_no_ext}-preview.webp"
 
-    # Skip if WebP preview already exists and is newer than source
-    if [ -f "$webp_file" ] && [ "$webp_file" -nt "$jpg_file" ]; then
-        echo -e "${YELLOW}Skipping $jpg_file (preview exists and is newer)${NC}"
-        return 0
+    # Check if WebP preview already exists
+    if [ -f "$webp_file" ]; then
+        echo -e "${YELLOW}Overriding existing preview: $webp_file${NC}"
+    fi
+
+    # Get image dimensions and calculate 50%
+    dimensions=$(identify -ping -format "%w %h" "$jpg_file" 2>/dev/null)
+    if [ $? -eq 0 ] && [ -n "$dimensions" ]; then
+        width=$(echo $dimensions | cut -d' ' -f1)
+        height=$(echo $dimensions | cut -d' ' -f2)
+        new_width=$((width / 2))
+        new_height=$((height / 2))
+        resize_params="-resize $new_width $new_height"
+        echo "Processing: $jpg_file -> $webp_file (${width}x${height} → ${new_width}x${new_height})"
+    else
+        # Fallback: no resizing if we can't get dimensions
+        resize_params=""
+        echo "Processing: $jpg_file -> $webp_file (no resize - couldn't get dimensions)"
     fi
 
     # Convert to WebP
-    echo "Processing: $jpg_file -> $webp_file"
-
-    if cwebp -q "$QUALITY" -m "$COMPRESSION" "$jpg_file" -o "$webp_file" 2>/dev/null; then
+    if cwebp -q "$QUALITY" -m "$COMPRESSION" $resize_params "$jpg_file" -o "$webp_file" 2>/dev/null; then
         # Check file sizes
         jpg_size=$(stat -f%z "$jpg_file" 2>/dev/null || stat -c%s "$jpg_file" 2>/dev/null)
         webp_size=$(stat -f%z "$webp_file" 2>/dev/null || stat -c%s "$webp_file" 2>/dev/null)