Jp2ksaveStream throws an error: Is Jpeg 2000 not fully implemented?

[michael-scott-phoseon]

We have images in a pyramidal tiff file that are of 81920 x 98304, so using JpegsaveStream won't work, as it has a 65500 x 65500 size limit. So we are trying to use Jp2ksaveSteam instead. However, it throws this error:

      NetVips.VipsException: 'no such operation jp2ksave_target VipsOperation: class "jp2ksave_target" not found

Does libvips and / or NetVips not support Jpeg 2000? We are trying to insert a libvips Image into a WPF Window, so are trying to move the stream into a BitmapSource. But I am even willing to place it into a Windows Forms Bitmap. Here is the method I'm using:

    private static BitmapImage NetVipsToImageSource(NetVips.Image img)
    {
        using (MemoryStream memory = new MemoryStream())
        {
            img.Jp2ksaveStream(memory);
            //img.JpegsaveStream(memory);
            //img.WriteToStream(memory, ".jpg");
            memory.Position = 0;
            BitmapImage bitmapImage = new BitmapImage();
            bitmapImage.BeginInit();
            bitmapImage.StreamSource = memory;
            bitmapImage.CacheOption = BitmapCacheOption.OnLoad;
            bitmapImage.EndInit();

            return bitmapImage;
        }
    }

Am I doing something wrong? Is Jpeg 2000 not supported? Is there another way to do this?

Michael

[kleisauke]

See #142 (comment) for the reason why saving to JPEG 2000 isn't supported by default.

You could use the NetVips.Extensions NuGet package for converting a GDI+ bitmap to NetVips and vice versa (with the ToBitmap() and ToVips() functions). It should be faster than encoding/decoding the image to a JPEG (or PNG, TIFF, etc.) memory stream. Note that the conversion to a WPF image isn't supported by this package (see #81).

[michael-scott-phoseon]

Kleis, I’ve installed NetVips.Extensions, and will look into .ToBitmap. However, I now have 3 NuGet packages installed: NetVips 2.0.1 : .NET bindings for libvips (though I suspect this may be a 32bit version of NetVips.Native.winx64 so may not need it, but am unsure) NetVips.Extensions 2.0.0: a set if extension methods and helpers for NetVips (heard a rumor that it contains a .ToBitmap method which may solve one of my other problems) NetVips.Native.win-64 8.11.4 (I suspect this replaces the need for NetVips 2.0.1) Is NetVips 2.0.1 necessary if I also have NetVips.Native.win-64 8.11.4 also installed? Or the other way around? And if I have one (or both) of these installed, do I *also* have libvips installed now? Or is that an entirely separate installation? Michael From: Kleis Auke Wolthuizen ***@***.***> Sent: Saturday, October 9, 2021 4:38 AM To: kleisauke/net-vips ***@***.***> Cc: Michael Scott ***@***.***>; Author ***@***.***> Subject: Re: [kleisauke/net-vips] Jp2ksaveStream throws an error: Is Jpeg 2000 not fully implemented? (#147) See #142 (comment)<#142 (comment)> for the reason why saving to JPEG 2000 isn't supported by default. You could use the NetVips.Extensions<https://www.nuget.org/packages/NetVips.Extensions> NuGet package for converting a GDI+ bitmap to NetVips and vice versa (with the ToBitmap() and ToVips() functions). It should be faster than encoding/decoding the image to a JPEG (or PNG, TIFF, etc.) memory stream. Note that the conversion to a WPF image isn't supported by this package (see #81<#81>). — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub<#147 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/ARZ2TV46MD3SGPPNZFE5BGLUGASSTANCNFSM5FUVE2TQ>. Triage notifications on the go with GitHub Mobile for iOS<https://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675> or Android<https://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub>. NOTICE: This communication may contain privileged or other confidential information. If you have received it in error, please advise the sender by reply email and immediately delete the message and any attachments without copying or disclosing the contents. Thank you.

[michael-scott-phoseon]

Sadly, ToBitmap isn't working. The method is failing on this line in your code:

 Bitmap bitmap = new Bitmap(src.Width, src.Height, format);

Which is equivalent to

 Bitmap bitmap = new Bitmap(28672, 28672, PixelFormat.Format24bppRgb);

This line fails because the image is too big.

So unless you guys have another idea, I'm looking into how I can load each individual tile on a Page instead of the entire page in a pyramidal file structure. Do you have any examples of that, instead of loading each page at once?

[kleisauke]

I'm not sure if there is a workaround for this GDI+ limitation other than avoiding System.Drawing or cropping and stitching the image (as John said in libvips/libvips#2478 (reply in thread)).

[kleisauke]

I hope this information helped. Please feel free to re-open if questions remain.