Sirv dynamic imaging URL API for on-the-fly image transformation. Use when building image URLs with Sirv CDN, resizing images via URL parameters, adding watermarks/text overlays, cropping, applying filters, format conversion (WebP, AVIF), or any Sirv URL-based image manipulation. Covers 100+ URL parameters for scaling, cropping, effects, text, watermarks, frames, and optimization.
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Transform images on-the-fly by adding URL parameters.
Base URL: https://yourcdn.sirv.com/path/image.jpg?{options}
| Option | Example | Description |
|---|---|---|
w | ?w=800 | Width (px or %) |
h | ?h=600 | Height (px or %) |
s | ?s=500 | Longest dimension |
thumbnail | ?thumbnail=200 | Square thumbnail |
scale.option | ?scale.option=fit | fit, fill, ignore, noup |
?w=800 # 800px wide
?w=50% # 50% of original width
?w=800&h=600 # Specific dimensions
?w=800&scale.option=fit # Fit within 800px (maintain aspect)
?w=800&scale.option=fill # Fill 800px (may crop)
| Option | Example | Description |
|---|---|---|
cw, ch | ?cw=500&ch=300 | Crop width/height |
cx, cy | ?cx=100&cy=50 | Crop start position |
crop.type | ?crop.type=face | Auto-crop: trim, poi, face |
?cw=500&ch=300&cx=100&cy=50 # Manual crop
?crop.type=face&w=400 # Face detection crop
?crop.type=trim # Trim whitespace
| Option | Example | Description |
|---|---|---|
format | ?format=webp | jpg, png, webp, avif, optimal |
q | ?q=85 | JPEG quality 0-100 |
webp-fallback | ?webp-fallback=jpg | Fallback for non-WebP browsers |
?format=webp&q=80 # WebP at 80% quality
?format=optimal # Auto-select best format
?format=avif # AVIF format
| Option | Range | Description |
|---|---|---|
blur | 0-100 | Gaussian blur |
sharpen | 0-100 | Sharpen |
brightness | -100 to 100 | Brightness |
contrast | -100 to 100 | Contrast |
saturation | -100 to 100 | Saturation |
grayscale | true/false | Black & white |
rotate | -180 to 180 | Rotation degrees |
colortone | preset name | sepia, warm, cold, sunset... |
?blur=10 # Light blur
?grayscale=true&contrast=20 # B&W with more contrast
?colortone=sepia # Sepia effect
?rotate=90 # Rotate 90 degrees
?text=Hello%20World
?text=Hello&text.size=30%&text.color=white&text.position=southeast
?text=©2024&text.font.family=Open%20Sans&text.opacity=50
?watermark=/logo.png
?watermark=/logo.png&watermark.position=southeast&watermark.opacity=50
?watermark=/logo.png&watermark.scale.width=20%
?canvas.width=1200&canvas.height=800&canvas.color=white
?frame.style=solid&frame.color=black&frame.width=10
<img
src="https://cdn.sirv.com/image.jpg?w=800"
srcset="
https://cdn.sirv.com/image.jpg?w=400 400w,
https://cdn.sirv.com/image.jpg?w=800 800w,
https://cdn.sirv.com/image.jpg?w=1200 1200w
"
sizes="(max-width: 600px) 100vw, 50vw"
alt="Description"
>
<picture>
<source srcset="https://cdn.sirv.com/image.jpg?format=avif" type="image/avif">
<source srcset="https://cdn.sirv.com/image.jpg?format=webp" type="image/webp">
<img src="https://cdn.sirv.com/image.jpg" alt="Description">
</picture>
?w=400&h=400&scale.option=fit&canvas.width=400&canvas.height=400&canvas.color=white
?watermark=/logo.png&watermark.position=southeast&watermark.opacity=30&dl
Save reusable option sets as JSON profiles in /Profiles/:
?profile=my-thumbnail
Profile example:
{
"image": {
"scale": {"width": 400},
"format": "webp",
"quality": 80
}
}