Question 1

What is color quantization?

Accepted Answer

Color quantization is the process of reducing the number of distinct colors in an image to a specified number N while minimizing visual quality loss. It is used in GIF compression (256 colors max), indexed color palettes, printing with limited inks, and extracting dominant colors for design. Common algorithms include median cut, k-means clustering, and octree quantization.

Question 2

What is the median cut algorithm?

Accepted Answer

Median cut divides the color space into buckets by recursively splitting the longest dimension of each bucket at its median value. Starting with all colors in one bucket, it splits into 2, then 4, 8... until N buckets are reached. Each bucket's representative color is the average of all colors in it. This produces a balanced palette distributed across the actual colors in the image.

Question 3

How many colors should I use for quantization?

Accepted Answer

The optimal number depends on the image and use case. 2-8 colors: bold graphic look, useful for logos and icons. 8-16 colors: stylized illustration look. 16-32 colors: natural-looking reduction for photographic content. For web palettes, 6-12 colors is a common design starting point. Experiment with different values to find the best balance for your specific image.

Question 4

Can I use quantized colors for web design?

Accepted Answer

Absolutely! Color quantization is an excellent way to extract a cohesive color palette from an image. Upload a brand photo, product image, or inspiration photo and extract 5-8 dominant colors to use as your color palette. This ensures harmony between images and design elements. The extracted hex codes can be directly used in CSS.

Question 5

What image formats work with this tool?

Accepted Answer

This tool works with any image format supported by the browser's Canvas API, including JPEG, PNG, WebP, GIF, BMP, and AVIF. Very large images are automatically scaled down for processing efficiency. The color analysis is performed on a reduced version of the image, then the palette is displayed at full quality. Transparent pixels (alpha < 128) are excluded from the analysis.

画像カラー量子化

よくある質問

Comments & Feedback