java.lang.NegativeArraySizeException

[jacksoftapp]

Hello, a java.lang.NegativeArraySizeException exception was reported. Can this be fixed? Thanks

[stanio]

Please don't post screenshots of error traces but the output text like:

% sh ./xbrz.sh 1_4.jpeg 4
Exception in thread "main" java.lang.NegativeArraySizeException: -1624375296
	at io.github.stanio.xbrz.awt.ImageData.<init>(ImageData.java:55)
	at io.github.stanio.xbrz.awt.AwtXbrz.scaleImage(AwtXbrz.java:55)
	at io.github.stanio.xbrz.awt.AwtXbrz.scaleImage(AwtXbrz.java:33)
	at io.github.stanio.xbrz.tool.ScalerTool$ScaledImageIterator.next(ScalerTool.java:129)
	at io.github.stanio.xbrz.tool.ScalerTool$ScaledImageIterator.next(ScalerTool.java:79)
	at io.github.stanio.xbrz.tool.ScalerTool.main(ScalerTool.java:61)

Could you specify the xbrz tool and java versions (java -version) you're using? Thank you.

Looking at the trace, it seems the input image is larger than what the tool could handle – what are the exact image dimensions (width and height)? More precisely, the result dimensions @4x the given input image are larger than what the tool could produce. I will improve the error reporting for the related cases in a future version of the tool, but it wouldn't make it process such images successfully.

Note, this tool is meant for processing relatively small pixel-art graphics and is not a general image scaling tool. Could you share your use case for scaling very large images with xBRZ?

[jacksoftapp]

The Test image size of 2608 x 4000 is 1.8M, and the file size after being enlarged by 4 times is 72M. Can you optimize the enlarged image in the later stage and make it smaller? thank you .

[stanio]

2608×4000 scaled by a factor of 4 would be 16 times the original size = 166,912,000 pixels – well within the limits. However, it doesn't match the observed exception: NegativeArraySizeException: -1624375296. The last number as unsigned long would be 2,670,592,000 – a "bit" over the maximum int value: 2,147,483,647.

It could be the source image is not decoded properly by the Java Image I/O library. If the test image is not private, could you share it here? You may also try saving it as PNG to use as a source for the xbrz tool.

[stanio]

... it doesn't match the observed exception: NegativeArraySizeException: -1624375296. The last number as unsigned long would be 2,670,592,000...

It does match:

 (2,608 × 4) × (4,000 × 4) = 10,432 × 16,000 = 166,912,000 pixels
(10,432 × 4) × (16,000 × 4) = 41,728 × 64,000 = 2,670,592,000 pixels

It looks like you're trying to scale a 10432×16000 (and not a 2608×4000) image by a factor of 4 which exceeds the implementation limits: target dimension of 41728×64000. For comparison – the maximum target image dimension is about 46000×46000:

sqrt(2,147,483,647) ≈ 46,340.95

Can you optimize the enlarged image in the later stage and make it smaller?

Not sure what you're up to, but xBRZ is not a compression algorithm. It is an upscaling algorithm originally meant for scaling up pixel-art graphics.