Files
squoosh/codecs/mozjpeg_enc/example.html
Jake Archibald f396a5b784 MozJPEG chroma subsampling and quality (#235)
* Adding chroma subsampling for mozjpeg

* Adding separate chroma quality.

* Preact sometimes removes the inline styles, this fixes it.

* Simplifying chroma subsample

* Adding comments
2018-11-06 13:46:52 +00:00

49 lines
1.4 KiB
HTML

<!doctype html>
<script src='mozjpeg_enc.js'></script>
<script>
const module = mozjpeg_enc();
async function loadImage(src) {
// Load image
const img = document.createElement('img');
img.src = src;
await new Promise(resolve => img.onload = resolve);
// Make canvas same size as image
const canvas = document.createElement('canvas');
[canvas.width, canvas.height] = [img.width, img.height];
// Draw image onto canvas
const ctx = canvas.getContext('2d');
ctx.drawImage(img, 0, 0);
return ctx.getImageData(0, 0, img.width, img.height);
}
module.onRuntimeInitialized = async _ => {
console.log('Version:', module.version().toString(16));
const image = await loadImage('../example.png');
const result = module.encode(image.data, image.width, image.height, {
quality: 75,
baseline: false,
arithmetic: false,
progressive: true,
optimize_coding: true,
smoothing: 0,
color_space: 3,
quant_table: 3,
trellis_multipass: false,
trellis_opt_zero: false,
trellis_opt_table: false,
trellis_loops: 1,
auto_subsample: true,
chroma_subsample: 2,
separate_chroma_quality: false,
chroma_quality: 75,
});
const blob = new Blob([result], {type: 'image/jpeg'});
const blobURL = URL.createObjectURL(blob);
const img = document.createElement('img');
img.src = blobURL;
document.body.appendChild(img);
};
</script>