Raster Graphics
Raster Graphics (Bitmap Image)
A type of digital image composed of a rectangular grid of individually colored pixels, where the image's quality and detail are determined by the total number of pixels and color depth.
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Raster images store color values for each pixel in a grid. Common formats include JPEG (lossy, 8-bit), PNG (lossless, 8/16-bit, alpha), WebP (lossy/lossless, alpha), AVIF (AV1-based, superior compression), TIFF (versatile, used in print/science), and BMP (uncompressed). Color depth determines the number of possible colors per pixel: 8-bit (256 colors), 24-bit (16.7M colors), and 32-bit (24-bit + 8-bit alpha). Raster images cannot be scaled up without quality loss, unlike vector graphics which store mathematical shape descriptions.
ไพ
```javascript
// Raster Graphics: processing with Canvas API
const canvas = document.createElement('canvas');
const ctx = canvas.getContext('2d');
ctx.drawImage(sourceImage, 0, 0);
const imageData = ctx.getImageData(0, 0, canvas.width, canvas.height);
// Process pixels in imageData.data (RGBA array)
```