selecting color of background when converting from png to jpg

Converting a png with a transparent background to jpg will change that color to black by default. Is there anyway to change this color? I can’t see to find any API that can do this. It seems like .background would be a candidate but the documentation isn’t very clear on what it does.

[targos]

Hi, to do this you would need to convert the transparent pixels to white. Here is a way this can be done:

// Load the image.
const image = await Image.load('image.png');
// Get the alpha channel.
const alpha = image.getChannel(3);
// Create a binary mask on the transparent pixels (255 = opaque).
const mask = alpha.mask({ threshold: 254, invert: true });
// Paint the pixels from the mask in white.
image.paintMasks(mask, { color: 'white' });
// Save the image as jpg.
await image.save('image.jpg');

.background is another method that tries to remove the “noise” in the background of an image to enhance it for use in other algorithms.

[toyssamurai]

There’s a problem with this solution – the mask is binary and the anti-aliasing edges would be lost. Does anyone know of a way that can keep the anti-aliasing?