Do not encode WEBP images exceeding max dimensions

Author: JimBobSquarePants

src/ImageSharp/Formats/Jpeg/JpegEncoderCore.cs

@@ -58,7 +58,7 @@ public void Encode<TPixel>(Image<TPixel> image, Stream stream, CancellationToken
         Guard.NotNull(image, nameof(image));
         Guard.NotNull(stream, nameof(stream));
 
-        if (image.Width >= JpegConstants.MaxLength || image.Height >= JpegConstants.MaxLength)
+        if (image.Width > JpegConstants.MaxLength || image.Height > JpegConstants.MaxLength)
         {
             JpegThrowHelper.ThrowDimensionsTooLarge(image.Width, image.Height);
         }

src/ImageSharp/Formats/Webp/Lossless/Vp8LEncoder.cs

@@ -371,9 +371,6 @@ public int EncodeAlphaImageData<TPixel>(Buffer2DRegion<TPixel> frame, IMemoryOwn
     /// <param name="inputImgHeight">The input image height.</param>
     private void WriteImageSize(int inputImgWidth, int inputImgHeight)
     {
-        Guard.MustBeLessThan(inputImgWidth, WebpConstants.MaxDimension, nameof(inputImgWidth));
-        Guard.MustBeLessThan(inputImgHeight, WebpConstants.MaxDimension, nameof(inputImgHeight));
-
         uint width = (uint)inputImgWidth - 1;
         uint height = (uint)inputImgHeight - 1;
 

src/ImageSharp/Formats/Webp/WebpEncoderCore.cs

@@ -132,6 +132,11 @@ public void Encode<TPixel>(Image<TPixel> image, Stream stream, CancellationToken
         Guard.NotNull(image, nameof(image));
         Guard.NotNull(stream, nameof(stream));
 
+        if (image.Width > WebpConstants.MaxDimension || image.Height > WebpConstants.MaxDimension)
+        {
+            WebpThrowHelper.ThrowDimensionsTooLarge(image.Width, image.Height);
+        }
+
         bool lossless;
         if (this.fileFormat is not null)
         {

src/ImageSharp/Formats/Webp/WebpThrowHelper.cs

@@ -18,4 +18,7 @@ internal static class WebpThrowHelper
 
     [DoesNotReturn]
     public static void ThrowInvalidImageDimensions(string errorMessage) => throw new InvalidImageContentException(errorMessage);
+
+    [DoesNotReturn]
+    public static void ThrowDimensionsTooLarge(int width, int height) => throw new ImageFormatException($"Image is too large to encode at {width}x{height} for WEBP format.");
 }