Unknown Color Type

[polycatenane]

The image doesn't load if color type is not specified.

org.gnome.glycin.Error.LoadingError: glycin-loaders/glycin-image-rs/src/main.rs:346:54: The encoder or decoder for Tiff does not support the color type Unknown(32)

[fintelia]

The underlying tiff crate understands arbitrary color types, but the image crate only supports a specific list of them:

image/src/codecs/tiff.rs

Lines 74 to 106 in 1ed88e4

	let color_type = match tiff_color_type {
	tiff::ColorType::Gray(1) => ColorType::L8,
	tiff::ColorType::Gray(8) => ColorType::L8,
	tiff::ColorType::Gray(16) => ColorType::L16,
	tiff::ColorType::GrayA(8) => ColorType::La8,
	tiff::ColorType::GrayA(16) => ColorType::La16,
	tiff::ColorType::RGB(8) => ColorType::Rgb8,
	tiff::ColorType::RGB(16) => ColorType::Rgb16,
	tiff::ColorType::RGBA(8) => ColorType::Rgba8,
	tiff::ColorType::RGBA(16) => ColorType::Rgba16,
	tiff::ColorType::CMYK(8) => ColorType::Rgb8,
	tiff::ColorType::RGB(32) => ColorType::Rgb32F,
	tiff::ColorType::RGBA(32) => ColorType::Rgba32F,
	tiff::ColorType::Palette(n) | tiff::ColorType::Gray(n) => {
	return Err(err_unknown_color_type(n))
	}
	tiff::ColorType::GrayA(n) => return Err(err_unknown_color_type(n.saturating_mul(2))),
	tiff::ColorType::RGB(n) => return Err(err_unknown_color_type(n.saturating_mul(3))),
	tiff::ColorType::YCbCr(n) => return Err(err_unknown_color_type(n.saturating_mul(3))),
	tiff::ColorType::RGBA(n) | tiff::ColorType::CMYK(n) => {
	return Err(err_unknown_color_type(n.saturating_mul(4)))
	}
	tiff::ColorType::Multiband {
	bit_depth,
	num_samples,
	} => {
	return Err(err_unknown_color_type(
	bit_depth.saturating_mul(num_samples.min(255) as u8),
	))
	}
	_ => return Err(err_unknown_color_type(0)),
	};