MonoGame/MonoGame · error · InvalidOperationException

Unexpected intermediate format: {intermediateFormat}

Error message

Unexpected intermediate format: {intermediateFormat}

What it means

Thrown by GraphicsUtil's bitmap resize routine when the intermediate SurfaceFormat used for the resize does not match one of the three supported formats (Color, Rgba64, Vector4). The switch expression's default arm raises this InvalidOperationException with the offending format.

Source

Thrown at MonoGame.Framework.Content.Pipeline/Graphics/GraphicsUtil.cs:81

                {
                    var errorMsg = Marshal.PtrToStringUTF8(err);
                    throw new InvalidContentException($"Bitmap resize failed: {errorMsg}");
                }
            }
            finally
            {
                if (srcHandle.IsAllocated)
                    srcHandle.Free();
                if (dstHandle.IsAllocated)
                    dstHandle.Free();
            }

            src = intermediateFormat switch
            {
                SurfaceFormat.Color => new PixelBitmapContent<Color>(newWidth, newHeight),
                SurfaceFormat.Rgba64 => new PixelBitmapContent<Rgba64>(newWidth, newHeight),
                SurfaceFormat.Vector4 => new PixelBitmapContent<Vector4>(newWidth, newHeight),
                _ => throw new InvalidOperationException($"Unexpected intermediate format: {intermediateFormat}"),
            };
            src.SetPixelData(newBytes);

            // Convert back to source type if required
            if (format != intermediateFormat)
            {
                var s = (T)Activator.CreateInstance(bitmap.GetType(), [newWidth, newHeight])!;
                BitmapContent.Copy(src, s);
                src = s;
            }

            if (src is not T ret)
            {
                throw new Exception($"Invalid return type for bitmap, expected {typeof(T)}, got {src}");
            }

            return ret;
        }

View on GitHub (pinned to 1d71bbd0ff)

Solutions

1. Convert the bitmap to an uncompressed PixelBitmapContent<Color> before resizing.
2. Ensure the source TextureContent face is a supported uncompressed format.
3. Extend the switch (if you control the codebase) to handle the additional intermediate format.

Example fix

// before
GraphicsUtil.Resize(compressedTextureFace, newWidth, newHeight);

// after
content.ConvertBitmapType(typeof(PixelBitmapContent<Color>));
GraphicsUtil.Resize(content.Faces[0][0], newWidth, newHeight);

var allowed = new[] { SurfaceFormat.Color, SurfaceFormat.Rgba64, SurfaceFormat.Vector4 };
var fmt = bitmap is BitmapContent bc ? /* resolve format */ SurfaceFormat.Color : throw new InvalidOperationException();
if (!allowed.Contains(fmt))
    throw new InvalidOperationException($"Convert bitmap to an uncompressed Color/Rgba64/Vector4 format before resizing; got {fmt}.");

static bool IsResizableFormat(BitmapContent bitmap) =>
    bitmap is PixelBitmapContent<Color>
        or PixelBitmapContent<Rgba64>
        or PixelBitmapContent<Vector4>;

try { GraphicsUtil.Resize(bitmap, newWidth, newHeight); }
catch (InvalidOperationException ex) when (ex.Message.Contains("Unexpected intermediate format"))
{
    content.ConvertBitmapType(typeof(PixelBitmapContent<Color>));
    GraphicsUtil.Resize(content.Faces[0][0], newWidth, newHeight);
}

When it happens

Trigger: The bitmap being resized reports an intermediate format outside {SurfaceFormat.Color, SurfaceFormat.Rgba64, SurfaceFormat.Vector4}. This intermediate format is derived from the source bitmap type during the resize pipeline.

Common situations: Passing a compressed (DXT/BCx/PVRTC/ETC) or exotic (HalfVector4, NormalizedByte4, etc.) bitmap content directly into the resize utility without first decompressing/converting it; a custom BitmapContent subclass returning an unexpected SurfaceFormat.

Related errors

• Could not retrieve surface format of source bitmap
• Could not retrieve surface format of destination bitmap
• DxtBitmapContent cannot compress format=[{format}]
• Bitmap resize failed: {errorMsg}
• Invalid return type for bitmap, expected {typeof(T)}, got {s

AI-assisted analysis of MonoGame/MonoGame@1d71bbd0ff (2026-08-13). Data as JSON: /api/errors/1f4425c627f683f9. Report an issue: GitHub.