Your IP : 216.73.216.86
export const sharpen = (
canvas: HTMLCanvasElement | OffscreenCanvas,
width: number,
height: number,
mixFactor: number,
): void => {
const context: CanvasRenderingContext2D = canvas.getContext('2d');
const weights: number[] = [0, -1, 0, -1, 5, -1, 0, -1, 0];
const katet: number = Math.round(Math.sqrt(weights.length));
const half: number = Math.trunc(katet * 0.5);
const destinationData: ImageData = context.createImageData(width, height);
const destinationBuffer: Uint8ClampedArray = destinationData.data;
const sourceBuffer: Uint8ClampedArray = context.getImageData(0, 0, width, height).data;
let y: number = height;
while (y--)
{
let x: number = width;
while (x--)
{
const sy: number = y;
const sx: number = x;
const dstOff: number = (y * width + x) * 4;
let red = 0;
let green = 0;
let blue = 0;
// let alpha = 0;
for (let cy = 0; cy < katet; cy++)
{
for (let cx = 0; cx < katet; cx++)
{
const scy: number = sy + cy - half;
const scx: number = sx + cx - half;
if (scy >= 0 && scy < height && scx >= 0 && scx < width)
{
const srcOff: number = (scy * width + scx) * 4;
const wt: number = weights[cy * katet + cx];
red += sourceBuffer[srcOff] * wt;
green += sourceBuffer[srcOff + 1] * wt;
blue += sourceBuffer[srcOff + 2] * wt;
// alpha += sourceBuffer[srcOff + 3] * wt;
}
}
}
destinationBuffer[dstOff] = red * mixFactor + sourceBuffer[dstOff] * (1 - mixFactor);
destinationBuffer[dstOff + 1] = green * mixFactor + sourceBuffer[dstOff + 1] * (1 - mixFactor);
destinationBuffer[dstOff + 2] = blue * mixFactor + sourceBuffer[dstOff + 2] * (1 - mixFactor);
destinationBuffer[dstOff + 3] = sourceBuffer[dstOff + 3];
}
}
context.putImageData(destinationData, 0, 0);
};
export const shouldSharpen = (imageData: CanvasImageSource, width: number, height: number): boolean => {
const scaleX: number = width / imageData.width;
const scaleY: number = height / imageData.height;
const scale: number = Math.min(scaleX, scaleY);
// if target scale is less than half
return scale < 0.5;
};