Image Effects
Apply creative effects to images including blur, pixelate, emboss & more. Transform ordinary photos into artistic visuals with one-click effects.
Upload an image to apply blur, sharpening, and other special effects.
About Image Effects
How to Use (30 seconds)
- 1.Upload your image using the file selector or drag-and-drop interface.
- 2.Adjust the Blur slider (0-100) to apply Gaussian blur with radius σ proportional to slider value.
- 3.Adjust the Sharpness slider (0-100) to apply unsharp masking with amount scaling.
- 4.Preview changes in real-time, then download the processed image in original format.
Technical Logic Behind Image Processing
Gaussian Blur Algorithm
Blur applies a Gaussian convolution kernel to each pixel, averaging neighboring pixels weighted by distance. The formula for a 2D Gaussian function is:
Where σ (sigma) is the standard deviation controlling blur radius. Our tool maps slider values linearly:
- Slider 0 → σ = 0 (no blur)
- Slider 50 → σ = 5 pixels
- Slider 100 → σ = 10 pixels (maximum blur)
Unsharp Masking for Sharpening
Sharpening uses unsharp masking (USM), a technique from analog photography. The process:
- Create a blurred copy of the original image (Gaussian blur with σ = 1)
- Subtract the blurred version from the original to create an edge mask
- Add the scaled mask back to the original image
Mathematical formula:
Amount scales from 0 (no sharpening) to 2.0 (maximum sharpening) based on slider position. Values above 1.5 may introduce haloing artifacts around high-contrast edges.
Understanding Your Results
Optimal Settings by Use Case
| Use Case | Blur Setting | Sharpness Setting | Purpose |
|---|---|---|---|
| Portrait Photography | 10-20 | 0-10 | Soften skin, reduce blemishes |
| Product Photography | 0 | 40-60 | Emphasize texture and detail |
| Background Separation | 60-100 | 0 | Create bokeh effect, isolate subject |
| Scanned Documents | 0 | 70-90 | Enhance text readability |
| Privacy/Anonymization | 80-100 | 0 | Obscure faces, license plates |
Quality Degradation Thresholds
Watch for these warning signs:
- Sharpness > 75: Haloing artifacts appear around edges (white/dark outlines)
- Blur > 50: Fine details become irrecoverable; avoid if re-editing later
- Combined extreme values: Blur + Sharpness both > 60 creates unnatural texture
Professional Techniques
💡 Pro Tip: Selective Sharpening Workflow
Professional photographers never sharpen entire images uniformly. Here's the technique most online tools won't tell you:
- Process twice: Export one version with sharpness at 50-60, another at 0
- Layer in external editor: Stack both versions in Photoshop/GIMP
- Mask strategically: Apply sharpness only to eyes, hair, and key details—leave smooth areas untouched
- Result: Natural-looking sharpness without over-processed skin or artifacts
💡 Pro Tip: Blur Radius and Image Resolution
The same slider value produces different visual results based on image resolution. For consistent blur across different images:
- 1080p images (1920×1080): Use slider values as-is
- 4K images (3840×2160): Double the slider value to match 1080p appearance
- 8K images (7680×4320): Quadruple the slider value
This is because σ (sigma) is measured in absolute pixels, not relative to image dimensions. A σ=5 blur on a 4K image appears half as strong as the same σ=5 on a 1080p image.
Technical Specifications
Processing Details
- •Color space: RGB processing with per-channel convolution (preserves color accuracy)
- •Kernel size: Automatically calculated as 6σ + 1 to ensure 99.7% Gaussian distribution capture
- •Edge handling: Reflect padding to avoid dark borders on blur operations
- •Bit depth preservation: Maintains original 8-bit or 16-bit depth (no quality loss from processing)
- •Performance: Client-side processing using WebGL acceleration (no server upload required)
Supported Formats
Input Formats
- • JPEG (.jpg, .jpeg)
- • PNG (.png)
- • WebP (.webp)
- • BMP (.bmp)
Output Formats
- • Matches input format
- • Original EXIF data preserved
- • Max file size: 50MB
- • Max resolution: 8192×8192px
Algorithm Comparison
Understanding alternatives helps you choose the right tool for your workflow:
| Method | Best For | Limitations |
|---|---|---|
| Gaussian Blur (This Tool) | Natural-looking blur, privacy masking, depth-of-field simulation | Uniform blur (no edge preservation) |
| Box Blur | Fast processing on mobile devices | Less smooth, visible artifacts |
| Bilateral Filter | Smoothing while preserving edges (portrait skin smoothing) | 10-20× slower than Gaussian |
| Unsharp Mask (This Tool) | General-purpose sharpening, text enhancement | Can amplify noise at high values |
| High Pass Filter | Extreme detail enhancement, texture emphasis | Requires manual layer blending |
Common Mistakes to Avoid
❌ Over-sharpening compressed JPEGs
Sharpening amplifies JPEG compression artifacts (8×8 pixel blocks). If your source image shows blocky patterns, reduce sharpness below 30 or convert to PNG before processing.
❌ Applying blur to remove background objects
Gaussian blur doesn't remove objects—it makes them semi-transparent. For actual background removal, use object detection tools with alpha masking instead.
❌ Sharpening already-sharp images
Images from modern cameras (post-2018) often have in-camera sharpening applied. Adding more creates unnatural crispness. Test at 20-30 first.
Technical References
- [1] Gonzalez, R. C., & Woods, R. E. (2018). Digital Image Processing (4th ed.). Pearson. Chapter 3: Image Enhancement in the Spatial Domain, pp. 127-156. (Gaussian blur mathematical foundation)
- [2] Polesel, A., Ramponi, G., & Mathews, V. J. (2000). Image enhancement via adaptive unsharp masking. IEEE Transactions on Image Processing, 9(3), 505-510. doi:10.1109/83.826787 (Unsharp masking algorithm standards)
This tool implements industry-standard algorithms as documented in peer-reviewed image processing literature. Processing occurs entirely client-side; no images are uploaded to servers.