Clear pixel buffers on decode.

src/ImageSharp/Formats/Jpeg/Components/Decoder/SpectralConverter{TPixel}.cs

@@ -201,7 +201,8 @@ internal class SpectralConverter<TPixel> : SpectralConverter, IDisposable
         this.pixelBuffer = allocator.Allocate2D<TPixel>(
             pixelSize.Width,
             pixelSize.Height,
-            this.Configuration.PreferContiguousImageBuffers);
+            this.Configuration.PreferContiguousImageBuffers,
+            AllocationOptions.Clean);
         this.paddedProxyPixelRow = allocator.Allocate<TPixel>(pixelSize.Width + 3);
 
         // Component processors from spectral to RGB

src/ImageSharp/Formats/Tga/TgaDecoderCore.cs

@@ -84,7 +84,7 @@ internal sealed class TgaDecoderCore : IImageDecoderInternals
                 throw new UnknownImageFormatException("Width or height cannot be 0");
             }
 
-            Image<TPixel> image = Image.CreateUninitialized<TPixel>(this.configuration, this.fileHeader.Width, this.fileHeader.Height, this.metadata);
+            Image<TPixel> image = new(this.configuration, this.fileHeader.Width, this.fileHeader.Height, this.metadata);
             Buffer2D<TPixel> pixels = image.GetRootFramePixelBuffer();
 
             if (this.fileHeader.ColorMapType == 1)