Convert

Change an image’s format. Transparency is flattened onto a background colour when the target format has no alpha channel.

Function

convert_image(input, &ConvertOptions) -> Vec<u8>

Language	Name
Rust	convert_image
JavaScript	convertImage
Python	convert_image
CLI	dusrelimage convert <input> --format webp -o out.webp

Options

Field	Type	Default	Meaning
format	ImageFormat	required	Jpeg, Png, WebP, Avif, Gif, Bmp.
quality	u8	80	Quality 1–100 for lossy targets.
background	Colour	white	Colour used to flatten transparency when the target has no alpha (JPEG, BMP).
progressive	bool	false	Progressive JPEG / interlaced PNG output.

Formats

	Decode (in)	Encode (out)
Supported	JPEG, PNG, WebP, GIF, BMP, TIFF	JPEG, PNG, WebP, AVIF, GIF, BMP
Not supported	HEIC, AVIF (input)	HEIC, TIFF

Examples

import { convertImage } from 'dusrelimage';

const webp = convertImage(input, { format: 'WebP', quality: 80 });
const jpg = convertImage(pngWithAlpha, { format: 'Jpeg', background: '#ffffff' });

from dusrelimage import convert_image

avif = convert_image(data, format="avif", quality=60)

dusrelimage convert photo.png --format webp --quality 80 -o photo.webp
dusrelimage convert logo.png --format jpeg --background "#000000" -o logo.jpg

v0.1.0 limits

AVIF is encode-only: AVIF input does not decode (UNSUPPORTED_FORMAT). AVIF encode is lossy-only / 8-bit (underlying crate limit). GIF encode is first-frame only for animated input — animation is dropped, not preserved. There is no HEIC support.

Errors

Code	When
INVALID_IMAGE	Input is not a decodable image.
UNSUPPORTED_FORMAT	Input format cannot be decoded, or the target cannot be encoded (e.g. HEIC).
INVALID_QUALITY	Quality outside 1–100.
IMAGE_TOO_LARGE	Over max_pixels (default 120,000,000).
EMPTY_INPUT	Empty input bytes.