ImageResizer Overflow error on large images begin scaled down

Question

Using version 4.2.5

I have an app that allows the user to upload a PDF, which then gets rasterized to an image stream (using HiQPDF) and I then use ImageResizer to scale it down.

In cases where the PDF has a very large print size, the resulting image that is rasterized is very large (30,000 px x 75,000 px) and as a result the Image.Build() is failing with the below error.

HiQPDF doesn't have any sort of size scaling options during rasterization, so I'm a bit stuck. Any ideas on if there is a way to get around this error?

Overflow error.

Stacktrace:

at System.Drawing.Graphics.CheckErrorStatus(Int32 status)
   at System.Drawing.Graphics.DrawImage(Image image, PointF[] destPoints, RectangleF srcRect, GraphicsUnit srcUnit, ImageAttributes imageAttr, DrawImageAbort callback, Int32 callbackData)
   at System.Drawing.Graphics.DrawImage(Image image, PointF[] destPoints, RectangleF srcRect, GraphicsUnit srcUnit, ImageAttributes imageAttr)
   at ImageResizer.ImageBuilder.InternalGraphicsDrawImage(ImageState state, Bitmap dest, Bitmap source, PointF[] targetArea, RectangleF sourceArea, Single[][] colorMatrix)
   at ImageResizer.ImageBuilder.RenderImage(ImageState s)
   at ImageResizer.ImageBuilder.Render(ImageState s)
   at ImageResizer.ImageBuilder.Process(ImageState s)
   at ImageResizer.ImageBuilder.BuildJobBitmapToBitmap(ImageJob job, Bitmap source, Boolean transparencySupported)
   at ImageResizer.ImageBuilder.BuildJobBitmapToStream(ImageJob job, Bitmap source, Stream dest)
   at ImageResizer.ImageBuilder.BuildJob(ImageJob job)
   at ImageResizer.ImageBuilder.BuildInternal(ImageJob job)
   at ImageResizer.ImageBuilder.BuildInQueue(ImageJob job, Boolean useSemaphore, Int32 maxQueuingMilliseconds, CancellationToken cancel)
   at ImageResizer.ImageBuilder.Build(ImageJob job)

Relevant Code:

string strInstructions = $"maxwidth={maxWidthPixels};maxheight={maxHeightPixels};format=jpg;mode=max;";
strInstructions += "quality=" + ImageSaveQuality + ";";

using (var updatedImageFileStream = new MemoryStream())
{
    ImageJob imageJob = new ImageJob(origFileStream, updatedImageFileStream,
        new Instructions(strInstructions)
    );
    imageJob.Build();

Answer 1

You may have hit the upper limit for a System.Drawing based system.

I would suggest using the ImageResizer replacement Imageflow.NET instead. It should also produce files with better compression.

string strInstructions = $"maxwidth={maxWidthPixels};maxheight={maxHeightPixels};format=jpg;mode=max;";
strInstructions += "quality=" + ImageSaveQuality + ";";
    
using var buildJob = new ImageJob();
var jobResult = await buildJob.BuildCommandString(
            new StreamSource(originalStream, true),
            new StreamDestination(destStream, true), strInstructions)
        .SetSecurityOptions(new SecurityOptions()
            .SetMaxDecodeSize(new FrameSizeLimit(80000, 80000, 80000))
            .SetMaxEncodeSize(new FrameSizeLimit(80000, 80000, 80000))
            .SetMaxFrameSize(new FrameSizeLimit(80000, 80000, 80000)))
        .Finish()
        .InProcessAsync();