size reduction images

This commit is contained in:
Simon Martens
2025-09-29 23:30:34 +02:00
parent 269d635f1d
commit 9a856527cc
5 changed files with 96 additions and 66 deletions

View File

@@ -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

View File

@@ -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

View File

@@ -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)

View File

@@ -546,8 +546,8 @@ class W extends HTMLElement {
if (!o && !r) {
const c = n.querySelector("div:first-child");
if (c) {
const u = c.getBoundingClientRect(), d = u.top >= 0, h = u.bottom <= window.innerHeight;
d && h && (l = !0);
const u = c.getBoundingClientRect(), d = u.top >= 0, p = u.bottom <= window.innerHeight;
d && p && (l = !0);
}
}
l && e.push(s);
@@ -564,8 +564,8 @@ class W extends HTMLElement {
const n = document.getElementById("scrollspy-nav"), s = n.getBoundingClientRect();
let o = 1 / 0, r = -1 / 0;
t.forEach((c) => {
const u = c.getBoundingClientRect(), d = u.top - s.top + n.scrollTop, h = d + u.height;
o = Math.min(o, d), r = Math.max(r, h);
const u = c.getBoundingClientRect(), d = u.top - s.top + n.scrollTop, p = d + u.height;
o = Math.min(o, d), r = Math.max(r, p);
});
let l = r - o;
i.style.top = `${o}px`, i.style.height = `${l}px`, i.style.opacity = "1", setTimeout(() => this.ensureMarkerVisibility(), 100);
@@ -603,7 +603,7 @@ class W extends HTMLElement {
document.documentElement.offsetHeight
), s = window.innerHeight, o = n - s, r = o > 0 ? window.scrollY / o : 0, l = t.clientHeight, u = t.scrollHeight - l;
if (u > 0) {
const d = r * u, h = i.getBoundingClientRect(), g = t.getBoundingClientRect(), p = h.top - g.top + t.scrollTop, f = l / 2, m = p - f, w = 0.7, b = w * d + (1 - w) * m, x = Math.max(0, Math.min(u, b)), E = t.scrollTop;
const d = r * u, p = i.getBoundingClientRect(), g = t.getBoundingClientRect(), h = p.top - g.top + t.scrollTop, f = l / 2, m = h - f, w = 0.7, b = w * d + (1 - w) * m, x = Math.max(0, Math.min(u, b)), E = t.scrollTop;
Math.abs(x - E) > 10 && t.scrollTo({
top: x,
behavior: "smooth"
@@ -820,17 +820,17 @@ class Y extends HTMLElement {
}, c = [];
this.places.forEach((u) => {
if (u.lat && u.lng) {
const d = parseFloat(u.lat), h = parseFloat(u.lng), g = l(d, h);
const d = parseFloat(u.lat), p = parseFloat(u.lng), g = l(d, p);
if (g.x >= 0 && g.x <= 100 && g.y >= 0 && g.y <= 100) {
c.push(g);
const p = document.createElementNS("http://www.w3.org/2000/svg", "circle");
p.setAttribute("cx", g.x.toString()), p.setAttribute("cy", g.y.toString()), p.setAttribute("r", "0.4"), p.setAttribute("fill", "white"), p.setAttribute("opacity", "0.7"), p.setAttribute("filter", "drop-shadow(0 0.05 0.08 rgba(0,0,0,0.15))"), p.style.cursor = "pointer", p.style.pointerEvents = "all", p.style.transition = "r 0.3s ease, fill 0.3s ease, stroke 0.3s ease, opacity 0.3s ease", p.addEventListener("mouseenter", () => {
p.getAttribute("fill") === "white" && (p.setAttribute("r", "0.6"), p.setAttribute("fill", "#f87171"), p.setAttribute("opacity", "1"));
}), p.addEventListener("mouseleave", () => {
p.getAttribute("fill") === "#f87171" && (p.setAttribute("r", "0.4"), p.setAttribute("fill", "white"), p.setAttribute("opacity", "0.7"));
const h = document.createElementNS("http://www.w3.org/2000/svg", "circle");
h.setAttribute("cx", g.x.toString()), h.setAttribute("cy", g.y.toString()), h.setAttribute("r", "0.4"), h.setAttribute("fill", "white"), h.setAttribute("opacity", "0.7"), h.setAttribute("filter", "drop-shadow(0 0.05 0.08 rgba(0,0,0,0.15))"), h.style.cursor = "pointer", h.style.pointerEvents = "all", h.style.transition = "r 0.3s ease, fill 0.3s ease, stroke 0.3s ease, opacity 0.3s ease", h.addEventListener("mouseenter", () => {
h.getAttribute("fill") === "white" && (h.setAttribute("r", "0.6"), h.setAttribute("fill", "#f87171"), h.setAttribute("opacity", "1"));
}), h.addEventListener("mouseleave", () => {
h.getAttribute("fill") === "#f87171" && (h.setAttribute("r", "0.4"), h.setAttribute("fill", "white"), h.setAttribute("opacity", "0.7"));
});
const f = `${u.name}${u.toponymName && u.toponymName !== u.name ? ` (${u.toponymName})` : ""}`;
p.dataset.placeId = u.id, p.dataset.tooltipText = f, p.addEventListener("mouseenter", (m) => this.showTooltip(m)), p.addEventListener("mouseleave", () => this.hideTooltip()), p.addEventListener("mousemove", (m) => this.updateTooltipPosition(m)), p.addEventListener("click", (m) => this.scrollToPlace(m)), e.appendChild(p), this.mapPoints.set(u.id, p);
h.dataset.placeId = u.id, h.dataset.tooltipText = f, h.addEventListener("mouseenter", (m) => this.showTooltip(m)), h.addEventListener("mouseleave", () => this.hideTooltip()), h.addEventListener("mousemove", (m) => this.updateTooltipPosition(m)), h.addEventListener("click", (m) => this.scrollToPlace(m)), e.appendChild(h), this.mapPoints.set(u.id, h);
}
}
}), c.length > 0 && this.autoZoomToPoints(c);
@@ -841,7 +841,7 @@ class Y extends HTMLElement {
e.forEach((v) => {
v.x < t && (t = v.x), v.x > i && (i = v.x), v.y < n && (n = v.y), v.y > s && (s = v.y);
});
const o = 0.06, r = i - t, l = s - n, c = r * o, u = l * o, d = Math.max(0, t - c), h = Math.min(100, i + c), g = Math.max(0, n - u), p = Math.min(100, s + u), f = h - d, m = p - g, w = 5 / 7, b = f / m;
const o = 0.06, r = i - t, l = s - n, c = r * o, u = l * o, d = Math.max(0, t - c), p = Math.min(100, i + c), g = Math.max(0, n - u), h = Math.min(100, s + u), f = p - d, m = h - g, w = 5 / 7, b = f / m;
let x = { x: d, y: g, width: f, height: m };
if (b > w) {
const v = f / w;
@@ -990,9 +990,9 @@ class Z extends HTMLElement {
if (!this.place || !this.place.lat || !this.place.lng || !this.pointsContainer)
return;
const e = { xmin: 2555e3, ymin: 135e4, xmax: 7405e3, ymax: 55e5 }, t = { lon: 10, lat: 52 }, i = (r, l) => {
const h = t.lon * Math.PI / 180, g = t.lat * Math.PI / 180, p = l * Math.PI / 180, f = r * Math.PI / 180, m = Math.sqrt(
2 / (1 + Math.sin(g) * Math.sin(f) + Math.cos(g) * Math.cos(f) * Math.cos(p - h))
), w = 6371e3 * m * Math.cos(f) * Math.sin(p - h), b = 6371e3 * m * (Math.cos(g) * Math.sin(f) - Math.sin(g) * Math.cos(f) * Math.cos(p - h)), x = w + 4321e3, E = b + 321e4, S = e.xmax - e.xmin, C = e.ymax - e.ymin, k = (x - e.xmin) / S * 100, L = (e.ymax - E) / C * 100;
const p = t.lon * Math.PI / 180, g = t.lat * Math.PI / 180, h = l * Math.PI / 180, f = r * Math.PI / 180, m = Math.sqrt(
2 / (1 + Math.sin(g) * Math.sin(f) + Math.cos(g) * Math.cos(f) * Math.cos(h - p))
), w = 6371e3 * m * Math.cos(f) * Math.sin(h - p), b = 6371e3 * m * (Math.cos(g) * Math.sin(f) - Math.sin(g) * Math.cos(f) * Math.cos(h - p)), x = w + 4321e3, E = b + 321e4, S = e.xmax - e.xmin, C = e.ymax - e.ymin, k = (x - e.xmin) / S * 100, L = (e.ymax - E) / C * 100;
return { x: k, y: L };
}, n = parseFloat(this.place.lat), s = parseFloat(this.place.lng), o = i(n, s);
if (o.x >= 0 && o.x <= 100 && o.y >= 0 && o.y <= 100) {
@@ -1004,10 +1004,10 @@ class Z extends HTMLElement {
u.setAttribute("offset", "0%"), u.setAttribute("stop-color", "#f56565");
const d = document.createElementNS("http://www.w3.org/2000/svg", "stop");
d.setAttribute("offset", "100%"), d.setAttribute("stop-color", "#e53e3e"), c.appendChild(u), c.appendChild(d), l.appendChild(c), r.appendChild(l), this.pointsContainer.appendChild(r);
const h = document.createElementNS("http://www.w3.org/2000/svg", "circle");
h.setAttribute("cx", o.x.toString()), h.setAttribute("cy", o.y.toString()), h.setAttribute("r", "0.8"), h.setAttribute("fill", "#dc2626"), h.setAttribute("stroke", "#b91c1c"), h.setAttribute("stroke-width", "0.05"), h.setAttribute("filter", "drop-shadow(0 0.05 0.1 rgba(0,0,0,0.2))"), h.style.cursor = "pointer", h.style.pointerEvents = "all", h.style.transition = "r 0.3s ease, fill 0.3s ease, stroke 0.3s ease, opacity 0.3s ease";
const p = document.createElementNS("http://www.w3.org/2000/svg", "circle");
p.setAttribute("cx", o.x.toString()), p.setAttribute("cy", o.y.toString()), p.setAttribute("r", "0.8"), p.setAttribute("fill", "#dc2626"), p.setAttribute("stroke", "#b91c1c"), p.setAttribute("stroke-width", "0.05"), p.setAttribute("filter", "drop-shadow(0 0.05 0.1 rgba(0,0,0,0.2))"), p.style.cursor = "pointer", p.style.pointerEvents = "all", p.style.transition = "r 0.3s ease, fill 0.3s ease, stroke 0.3s ease, opacity 0.3s ease";
const g = `${this.place.name}${this.place.toponymName && this.place.toponymName !== this.place.name ? ` (${this.place.toponymName})` : ""}`;
h.dataset.tooltipText = g, h.addEventListener("mouseenter", (p) => this.showTooltip(p)), h.addEventListener("mouseleave", () => this.hideTooltip()), h.addEventListener("mousemove", (p) => this.updateTooltipPosition(p)), r.appendChild(h), this.autoZoomToPoint(o);
p.dataset.tooltipText = g, p.addEventListener("mouseenter", (h) => this.showTooltip(h)), p.addEventListener("mouseleave", () => this.hideTooltip()), p.addEventListener("mousemove", (h) => this.updateTooltipPosition(h)), r.appendChild(p), this.autoZoomToPoint(o);
}
}
autoZoomToPoint(e) {
@@ -1022,16 +1022,16 @@ class Z extends HTMLElement {
d.x = i - (b - r) / 2, d.width = b;
}
d.x < 0 && (d.width += d.x, d.x = 0), d.y < 0 && (d.height += d.y, d.y = 0), d.x + d.width > 100 && (d.width = 100 - d.x), d.y + d.height > 100 && (d.height = 100 - d.y);
const h = 30;
if (d.width < h) {
const b = (h - d.width) / 2;
d.x = Math.max(0, d.x - b), d.width = Math.min(h, 100 - d.x);
const p = 30;
if (d.width < p) {
const b = (p - d.width) / 2;
d.x = Math.max(0, d.x - b), d.width = Math.min(p, 100 - d.x);
}
if (d.height < h) {
const b = (h - d.height) / 2;
d.y = Math.max(0, d.y - b), d.height = Math.min(h, 100 - d.y);
if (d.height < p) {
const b = (p - d.height) / 2;
d.y = Math.max(0, d.y - b), d.height = Math.min(p, 100 - d.y);
}
const g = 100 / d.width, p = -d.x, f = -d.y, m = `scale(${g}) translate(${p}%, ${f}%)`, w = this.querySelector(".transform-wrapper");
const g = 100 / d.width, h = -d.x, f = -d.y, m = `scale(${g}) translate(${h}%, ${f}%)`, w = this.querySelector(".transform-wrapper");
w && (w.style.transform = m);
}
showTooltip(e) {
@@ -1244,17 +1244,17 @@ class J extends HTMLElement {
show(e, t, i, n = !1, s = 0, o = null, r = null, l = null) {
const c = this.querySelector("#single-page-image"), u = this.querySelector("#page-number"), d = this.querySelector("#page-icon");
this.querySelector("#page-indicator"), c.src = e, c.alt = t, this.currentPageNumber = i, this.currentIsBeilage = n, this.currentPartNumber = o;
let h;
let p;
if (l)
h = l;
p = l;
else {
const p = this.getIssueContext(i);
h = p ? `${p}, ${i}` : `${i}`;
const h = this.getIssueContext(i);
p = h ? `${h}, ${i}` : `${i}`;
}
if (u.innerHTML = h, s && i === s) {
if (u.innerHTML = p, s && i === s) {
u.style.position = "relative";
const p = u.querySelector(".target-page-dot");
p && p.remove();
const h = u.querySelector(".target-page-dot");
h && h.remove();
const f = document.createElement("span");
f.className = "target-page-dot absolute -top-1 -right-1 w-3 h-3 bg-red-500 rounded-full z-10", f.title = "verlinkte Seite", u.appendChild(f);
}
@@ -1386,13 +1386,14 @@ class J extends HTMLElement {
o = i.getAttribute("data-page-icon-type"), i.querySelector(".part-number") && (o = "part-number");
const c = i.querySelector(".page-indicator");
if (c) {
const u = c.cloneNode(!0);
u.querySelectorAll("i").forEach((g) => g.remove()), u.querySelectorAll(
const d = c.cloneNode(!0);
d.querySelectorAll("i").forEach((h) => h.remove()), d.querySelectorAll(
'[class*="target-page-dot"], .target-page-indicator'
).forEach((g) => g.remove()), r = u.textContent.trim();
).forEach((h) => h.remove()), r = d.textContent.trim();
}
const u = n.getAttribute("data-full-image") || n.src;
this.show(
n.src,
u,
n.alt,
e,
this.currentIsBeilage,
@@ -1446,9 +1447,9 @@ class J extends HTMLElement {
const u = c.textContent.trim(), d = u.match(/(\d{1,2}\.\d{1,2}\.\d{4}\s+Nr\.\s+\d+)/);
if (d)
return d[1];
const h = u.match(/(\d{4})\s+Nr\.\s+(\d+)/);
if (h)
return `${h[1]} Nr. ${h[2]}`;
const p = u.match(/(\d{4})\s+Nr\.\s+(\d+)/);
if (p)
return `${p[1]} Nr. ${p[2]}`;
}
}
const l = document.title.match(/(\d{4}).*Nr\.\s*(\d+)/);
@@ -1662,7 +1663,7 @@ class Q extends HTMLElement {
}
const o = t.getBoundingClientRect(), r = e.getBoundingClientRect();
if (!(r.top >= o.top && r.bottom <= o.bottom)) {
const c = t.scrollTop, u = r.top - o.top + c, d = o.height, h = r.height, g = u - (d - h) / 2;
const c = t.scrollTop, u = r.top - o.top + c, d = o.height, p = r.height, g = u - (d - p) / 2;
t.scrollTo({
top: Math.max(0, g),
behavior: "smooth"
@@ -1756,9 +1757,9 @@ function te(a, e, t, i = null) {
let l = null, c = null;
if (r) {
l = r.getAttribute("data-page-icon-type"), r.querySelector(".part-number") && (l = "part-number");
const h = r.querySelector(".page-indicator");
if (h) {
const g = h.cloneNode(!0);
const p = r.querySelector(".page-indicator");
if (p) {
const g = p.cloneNode(!0);
g.querySelectorAll("i").forEach((m) => m.remove()), g.querySelectorAll('[class*="target-page-dot"], .target-page-indicator').forEach((m) => m.remove()), c = g.textContent.trim();
}
}
@@ -2044,8 +2045,8 @@ function N() {
else {
const l = a.match(/^\/(\d{4})\/(\d+)(?:\/(\d+))?$/), c = o.match(/^\/(\d{4})\/(\d+)$/);
if (l && c) {
const [, u, d, h] = l, [, g, p] = c;
u === g && d === p && (r = !0);
const [, u, d, p] = l, [, g, h] = c;
u === g && d === h && (r = !0);
}
}
r ? (s.classList.add("text-red-700", "pointer-events-none"), s.setAttribute("aria-current", "page")) : (s.classList.remove("text-red-700", "pointer-events-none"), s.removeAttribute("aria-current"));

View File

@@ -527,9 +527,12 @@ export class SinglePageViewer extends HTMLElement {
extractedHeading = indicatorClone.textContent.trim();
}
// Use full-quality image for single page viewer (not the preview src)
const fullImageSrc = imgElement.getAttribute('data-full-image') || imgElement.src;
// Update the current view with the new page
this.show(
imgElement.src,
fullImageSrc,
imgElement.alt,
pageNumber,
this.currentIsBeilage,