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April 29, 2024 11:41
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Rotate base64 image (Javascript)
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function rotate(srcBase64, degrees, callback) { | |
const canvas = document.createElement('canvas'); | |
const ctx = canvas.getContext('2d'); | |
const image = new Image(); | |
image.onload = function () { | |
canvas.width = degrees % 180 === 0 ? image.width : image.height; | |
canvas.height = degrees % 180 === 0 ? image.height : image.width; | |
ctx.translate(canvas.width / 2, canvas.height / 2); | |
ctx.rotate(degrees * Math.PI / 180); | |
ctx.drawImage(image, image.width / -2, image.height / -2); | |
callback(canvas.toDataURL()); | |
}; | |
image.src = srcBase64; | |
} | |
// Usage: | |
const img = document.getElementById('image'); | |
rotate(img.attributes.src.value, 90, function(resultBase64) { | |
img.setAttribute('src', resultBase64); | |
}); |
thank you.
Thank you for this 👍
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Thank you!
I just needed these 2 lines:
canvas.width = degrees % 180 === 0 ? image.width : image.height;
canvas.height = degrees % 180 === 0 ? image.height : image.width;