ICO: Writing using default compression (uncompressed) creates inverted colors

[muyitimha]

<dependency>
	<groupId>com.twelvemonkeys.imageio</groupId>
	<artifactId>imageio-bmp</artifactId>
	<version>3.12.0</version>
</dependency> 

This is the bmp plugin for the Twelve monkeys introduced in the project.

private String transfer(
	String source,
	String destination,
	String format
) {
	try {
		BufferedImage image = ImageIO.read(new File(source));
		boolean success = ImageIO.write(image, format, new File(destination));
		if (success==false) {
			return "Failed";
		}else {
			return null;
		}
	} catch (Exception e) {
		log.error("",e);
		return "Exception";
	}
} 

This is my transfer method.

Hi, haraldk.
ImageIO.getReaderFileSuffixes() and ImageIO.getWriterFileSuffixes(), both printed out ico. When I used the transfer method to transfer jpeg image to ico image, ImageIO.write(image, format, new File(destination)) returnd false.
Would you tell me how to transfer jpeg image to ico image?

[haraldk]

Hi again,

Keep in mind that the ICO format is not a general purpose image format, it's for icons only. Thus, not a lot of effort has been put into making it support all kinds of input, as the format itself supports only a limited set of image types and sizes. There is work in progress to expand the types of images supported, but currently only TYPE_4BYTE_ABGR is supported. Any other type must be converted to this type.

Also, the max value of any dimension for an ICO is 256. Anything larger cannot be written as the format does not support it. Finally, for best compatibility, the icons should be square, and only dimensions that are multiples of 2, typically 16, 24, 32, 48 or 256 should be used.

PS: I have updated the Wiki page with this information.

[muyitimha]

I modified the code according to your prompt:

private String transfer(
	String source,
	String destination
) {
	// Create input stream (in try-with-resource block to avoid leaks)
	try (
		ImageInputStream input = ImageIO.createImageInputStream(new File(source));
		ImageOutputStream output = ImageIO.createImageOutputStream(new File(destination))
	) {
		// Get the reader
		Iterator<ImageReader> readers = ImageIO.getImageReaders(input);

		if (!readers.hasNext()) {
			throw new IllegalArgumentException("No reader for: " + "jpeg");
		}

		ImageReader reader = readers.next();
		reader.setInput(input);
		BufferedImage image = reader.read(0);
		
		//try to change the type
		BufferedImage type4ByteABGR = ImageUtil.toBuffered(image, BufferedImage.TYPE_4BYTE_ABGR);
		
		// Get the writer
		Iterator<ImageWriter> writers = ImageIO.getImageWritersByFormatName("ico");

		if (!writers.hasNext()) {
			throw new IllegalArgumentException("No writer for: " + "ico");
		}
		
		ImageWriter writer = writers.next();
		writer.setOutput(output);

		// Optionally, provide thumbnails and image/stream metadata
//			        writer.write(..., new IIOImage(..., image, ...), param);
		writer.write(type4ByteABGR);
		
		reader.dispose();
		writer.dispose();
	} catch (Exception e) {
		log.error("",e);
		return "exception";
	} finally {
		
	}
	
	return null;
}

I used a 256256 jpeg as sorce and got a 256256 ico, but the color of the ico is different from the color of the jpeg. I tried to use ImageUtil.toBuffered(image, BufferedImage.TYPE_4BYTE_ABGR) to change the type of ico, but maybe it did not work. How do I generate TYPE_4BYTE_ABGR ico?

[haraldk]

In what way was the colors "different"? Please include the source JPEG and output ICO for reference.

It does seem to work fine for me.

I used the sample code from ICOImageWriter (just added the TYPE_4BYTE_ABGR conversion in case the input wasn't already the correct format):

    if (!pngCompression) {
        image.setRenderedImage(ImageUtil.toBuffered(image.getRenderedImage(), BufferedImage.TYPE_4BYTE_ABGR));
    }
    writer.writeToSequence(image, param);

PS: Please use proper markdown to get correct code formatting (I fixed it for you above) to make the code readable.

[muyitimha]

Sorry, I didn't format the code.

This is the source JPEG.

This is a PNG image that looks exactly like the output ICO. Since the ICO doesn't allow uploads, I uploaded PNG.

And then I changed the code to this:

private String transfer(
	String source,
	String destination
) {
	// Create input stream (in try-with-resource block to avoid leaks)
	try (
		ImageInputStream input = ImageIO.createImageInputStream(new File(source));
		ImageOutputStream output = ImageIO.createImageOutputStream(new File(destination))
	) {
	    // Get the reader
	    Iterator<ImageReader> readers = ImageIO.getImageReaders(input);

	    if (!readers.hasNext()) {
	        throw new IllegalArgumentException("No reader for: " + "jpeg");
	    }

	    ImageReader reader = readers.next();
            reader.setInput(input);
            BufferedImage image = reader.read(0);
        
            //BufferedImage type4ByteABGR = ImageUtil.toBuffered(image, BufferedImage.TYPE_4BYTE_ABGR);
        
            IIOImage iIOImage = new IIOImage(image, null, null);
            iIOImage.setRenderedImage(ImageUtil.toBuffered(iIOImage.getRenderedImage(), BufferedImage.TYPE_4BYTE_ABGR));
	    
	    // Get the writer
	    Iterator<ImageWriter> writers = ImageIO.getImageWritersByFormatName("ico");

	    if (!writers.hasNext()) {
	        throw new IllegalArgumentException("No writer for: " + "ico");
	    }
	    
	    ImageWriter writer = writers.next();
	    writer.setOutput(output);
	    writer.write(iIOImage);
	    
	    reader.dispose();
	    writer.dispose();
	} catch (Exception e) {
		log.error("",e);
	} finally {
		
	}
	
	return null;
}

The output ICO is still the same, with the wrong color. Please help me see how I can get the right color ICO.

[haraldk]

Thanks! I can reproduce now, I get the same ICO as you with the inverted colors (seems like the red and blue channel is swapped).

I was testing with a work in progress version of the same code, and it doesn't have the issue, so I think we can fix this. But the bug is there in 3.12 and it will take some time to sort.

In the meantime, you should be able to work around the issue by using an ImageWriteParam with compression set to PNG:

    ImageWriteParam param = icoWriter.getDefaultWriteParam();
    param.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);
    param.setCompressionType("BI_PNG"); // Allowed values for ICO are "BI_RGB" (default) and "BI_PNG"
                // (and "BI_RLE8"and "BI_RLE4", however the RLE compressions are only for indexed color model
                //  and currently not supported)

    // ...

    icoWriter.write(null, iioImage, param);

Sorry about the inconvenience...

[muyitimha]

I should be the one to say thank you. I can generate the correct ICO now.

param.setCompressionType("BI_PNG"); Does this line of code make the ICO image actually contain a png image?

[haraldk]

param.setCompressionType("BI_PNG"); Does this line of code make the ICO image actually contain a png image?

Yes, it does. The ICO format just becomes a container format, the actual image data is in PNG format.

This is common for many file formats. Apple's ICNS icon file format does the same, they allow PNG and JP2K (JPEG 2000) compressed icons in addition to their old proprietary image format.

[muyitimha]

Thanks, it seems to have met my needs.

Before I output this ICO picture with a wrong color, what kind of picture does it actually contain, is it also PNG?

[haraldk]

No, the default way to store ICO using our writer uses the "internal" ICO format. This is basically the same as BMP (or DIB, for device independent bitmap), see Wikipedia.

[muyitimha]

Thanks, Haraldk, you've been a big help. Now I can generate good ICO image.