Color Blindness Simulator (Image) Simulate how images appear to people with various types of color vision deficiency.

The tool works under the hood by utilizing the Canvas API to apply color transformation matrices to images on a per-pixel basis. It supports five distinct modes of color blindness simulation, each represented as a 3x3 matrix in the TYPES array. When an image is uploaded and a simulation type is selected, the corresponding matrix is applied to the RGB values of each pixel using the formula d[i] = Math.min(255, r * m[0] + g * m[1] + b * m[2]), where d represents the resulting pixel data, r, g, and b are the original red, green, and blue values, and m is the transformation matrix. The transformed pixel data is then written back to the canvas using putImageData.

The tool uses React hooks such as useState, useRef, and useCallback to manage state changes and optimize performance. For instance, when an image is uploaded, the handleFile function creates a URL object for the file using URL.createObjectURL, which is then stored in the component's state. The useEffect hook ensures that this URL object is revoked when the component unmounts or the image is changed, preventing memory leaks.

The simulation process involves extracting pixel data from the original image using getImageData, applying the transformation matrix to each pixel, and writing the resulting data back to a new canvas element. This new canvas element serves as a temporary buffer for the simulated image, which can then be displayed alongside the original or downloaded as a PNG file using the toDataURL method.

In terms of specific technologies used, the tool relies on React for building the user interface, TypeScript for type checking and code compilation, and the Canvas API for graphics rendering. The FileDropzone component handles file uploads, while the glass-button class is used for styling purposes. Overall, the tool's implementation involves a combination of image processing algorithms, browser APIs, and modern web development frameworks to provide an accurate simulation of color blindness effects on images.