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Set missing LICENSE header to white balance process

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Igor Zinken
2026-08-01 12:59:51 +02:00
parent a5bd3fb7a5
commit 2844addf48
1 changed files with 29 additions and 9 deletions
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38
src/rendering/filters/white-balance.ts
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@@ -1,33 +1,53 @@
/**
* The MIT License (MIT)
*
* Igor Zinken 2026 - https://www.igorski.nl
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of
* this software and associated documentation files (the "Software"), to deal in
* the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
* the Software, and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
* FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
export const applyWhiteBalance = ( pixels: Uint8ClampedArray ): void => {
const totalPixels = pixels.length / 4;
let totalR = 0, totalG = 0, totalB = 0;
// Step 1: Calculate the sum of all RGB values
// calculate the sum of all RGB values
for ( let i = 0, len = pixels.length; i < len; i += 4) {
totalR += pixels[ i ];
totalG += pixels[ i + 1 ];
totalB += pixels[ i + 2 ];
}
// Step 2: Find the average value for each channel
// find the average value for each channel
const avgR = totalR / totalPixels;
const avgG = totalG / totalPixels;
const avgB = totalB / totalPixels;
// Step 3: Calculate the overall average brightness
// calculate the overall average brightness
const avgGray = ( avgR + avgG + avgB ) / 3;
// Step 4: Calculate scaling factors for each channel
// apply scaling factors per channel
const scaleR = avgGray / avgR;
const scaleG = avgGray / avgG;
const scaleB = avgGray / avgB;
// Step 5: Apply the scaling factors to every pixel
for ( let i = 0, len = pixels.length; i < len; i += 4 ) {
pixels[i] = Math.min(255, pixels[i] * scaleR); // New Red
pixels[i + 1] = Math.min(255, pixels[i + 1] * scaleG); // New Green
pixels[i + 2] = Math.min(255, pixels[i + 2] * scaleB); // New Blue
// data[i+3] is Alpha (transparency), leave it unchanged
pixels[ i ] = Math.min( 255, pixels[ i ] * scaleR );
pixels[ i + 1 ] = Math.min( 255, pixels[ i + 1 ] * scaleG );
pixels[ i + 2 ] = Math.min( 255, pixels[ i + 2 ] * scaleB );
}
};