What is Chroma Subsampling?

Chroma Subsampling — 4:2:0 vs 4:4:4 Color Resolution

Chroma subsampling reduces the color resolution of an image while preserving full brightness (luminance) detail. Human eyes are less sensitive to color changes than brightness changes, making this an efficient compression technique.

Détail technique

Expressed as ratios like 4:4:4 (no subsampling), 4:2:2 (half horizontal color resolution), and 4:2:0 (quarter color resolution). JPEG typically uses 4:2:0, reducing file size by 50% compared to 4:4:4.

Exemple

```javascript
// Image compression via Canvas
canvas.toBlob(
  blob => console.log(`Size: ${(blob.size/1024).toFixed(0)} KB`),
  'image/jpeg',
  0.8  // quality: 0.0 (smallest) to 1.0 (best)
);

// WebP output (25-34% smaller than JPEG)
canvas.toBlob(cb, 'image/webp', 0.8);
```

Formats associés

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Outils associés

C Compress Image R Resize Image C Crop Image R Rotate Image F Flip Image C Convert Image W Watermark Image S SVG to PNG I Image to Base64 R Round Corners A Add Border I Image Filters A Adjust Image B Blur Image S Sharpen Image M Make Square G Grayscale Image S Sepia Image P Pixelate Image S Strip Image Metadata

Termes associés

Alpha Channel Aspect Ratio AVIF Chromatic Aberration Color Grading (Image) Compression Artifact Dithering (Image) Image Histogram Image Registration Metadata Resolution Alpha Compositing Image Pyramid Rasterization Bit Depth Color Space Lossy Compression HDR Raster Graphics Vector Graphics Sprite Sheet Thumbnail WebP Crop Image Optimization Resize ICC Profile Image Interpolation Chroma Key Canvas Convolution DPI/PPI Gamma Histogram Noise Reduction (Image) Panorama Stitching Feature Matching Image Segmentation Object Detection Mipmap Morphological Operations Texture Atlas Gamut Mapping IPTC Tone Mapping Focus Stacking Vignetting XMP Batch Resize Content-Aware Fill Lossless Compression EXIF Color Profile DPI