Imagesharp: "CRC Error. PNG Image chunk is corrupt!" when loading certain image

[devedse]

Prerequisites

• [X] I have written a descriptive issue title
• [X] I have verified that I am running the latest version of ImageSharp
• [X] I have verified if the problem exist in both DEBUG and RELEASE mode
• [X] I have searched open and closed issues to ensure it has not already been reported

Description

When loading the image below I run into an issue that ImageSharp says that the PNG Image chunk is corrupt.

versioning-1_1.zip

Steps to Reproduce

Simply load it using Image.Load();

// Loads the image
Image.Load(imagePath);

System Configuration

• ImageSharp version: 1.0.0-alpha9-00176
• Other ImageSharp packages and versions: -
• Environment (Operating system, version and so on): Windows 10
• .NET Framework version: .NET Core
• Additional information: -

[dlemstra]

I get the following error with ImageMagick:

identify: zTXt: CRC error 'versioning-1_1.png' @ warning/png.c/MagickPNGWarningHandler/1709.

Maybe this will help someone solve the issue. It looks like the image chunk is not corrupt.

[JimBobSquarePants]

What's that error telling me?

[dlemstra]

In ImageMagick we just report a warning when the CRC of the zTXt is incorrect. I just did a quick check of our decoder and we report corrupt Image Chunk for every chunk. I thought this was an exception for an invalid IDAT chunk. I wonder if we should only throw an exception when the CRC of a critical chunk is invalid? Maybe we could also include the name of the chunk in the exception?

[xakep139]

Is this issue related to #276?

[JimBobSquarePants]

Most likely. We should double check the PR against all given images in both issues

[devedse]

Ah, I apparently didn't look good enough in the open issues. My apologies.

[devedse]

Thanks for fixing all these issues so quickly guys :smile: