Can't output png

Agachee

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Jul 4, 2024, 8:03:55 AMJul 4

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I am trying to merge 2 images (tif and exr) and output them as png with the ImageWriter node, but I get an error. It creates the file on the disk but it's corrupted and empty. It worked fine before with exr + exr / hdr + exr, I think it might be the tif format that's doing something here (maybe I'm wrong). I can output them as jpg tho. Any ideas what to do?

ERROR [Errors Occurred During Dispatch] Gaffer.ProcessException: Process_LgtTex.ConvertPNG.task : Could not open "/library/lgt/lgtTex/lgtTex00072/preview/00072_preview.01.png", error = PNG write error: profile 'Embedded Profile': 1h: too short
PNG write error: No IDATs written into file
Could not set PNG iCCP chunk

John Haddon

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Jul 4, 2024, 11:41:28 AMJul 4

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Sounds like a bug, either in Gaffer's ImageWriter or in the underlying libraries (OIIO/PNG). Best thing to do would be to find a way we can reproduce it at our end. Can you share the images with us?

Cheers...

John

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Agachee

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Jul 8, 2024, 7:45:25 PMJul 8

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Hey John, I couldn't upload it here for some reason it said the message was too long... But I managed to send it directly to you (I think). Can you confirm?

John Haddon

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Jul 9, 2024, 5:58:58 AMJul 9

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On Tue, Jul 9, 2024 at 12:45 AM Agachee <angel...@gmail.com> wrote:

Hey John, I couldn't upload it here for some reason it said the message was too long... But I managed to send it directly to you (I think). Can you confirm?

Yes, I have received the test data thanks. It turns out this was actually a bug in the ImageReader - it was corrupting the ICCProfile metadata on loading, causing the ImageWriter to fail when trying to write that data to PNG. I've fixed it here :

https://github.com/ImageEngine/cortex/pull/1425

In the meantime, you should be able to work around the problem using the DeleteImageMetadata node to delete the ICCProfile metadata before writing the image.