Initialize pixel type info from decoder.

Author: JimBobSquarePants

src/ImageSharp/Formats/Bmp/BmpDecoderCore.cs

@@ -208,7 +208,7 @@ public Image<TPixel> Decode<TPixel>(BufferedReadStream stream, CancellationToken
     public ImageInfo Identify(BufferedReadStream stream, CancellationToken cancellationToken)
     {
         this.ReadImageHeaders(stream, out _, out _);
-        return new ImageInfo(new PixelTypeInfo(this.infoHeader.BitsPerPixel), new(this.infoHeader.Width, this.infoHeader.Height), this.metadata);
+        return new ImageInfo(new(this.infoHeader.Width, this.infoHeader.Height), this.metadata);
     }
 
     /// <summary>

src/ImageSharp/Formats/Gif/GifDecoderCore.cs

@@ -249,7 +249,6 @@ public ImageInfo Identify(BufferedReadStream stream, CancellationToken cancellat
         }
 
         return new ImageInfo(
-            new PixelTypeInfo(this.logicalScreenDescriptor.BitsPerPixel),
             new(this.logicalScreenDescriptor.Width, this.logicalScreenDescriptor.Height),
             this.metadata,
             framesMetadata);

src/ImageSharp/Formats/ImageDecoder.cs

@@ -307,6 +307,7 @@ internal void SetDecoderFormat(Configuration configuration, ImageInfo info)
         if (configuration.ImageFormatsManager.TryFindFormatByDecoder(this, out IImageFormat? format))
         {
             info.Metadata.DecodedImageFormat = format;
+            info.PixelType = info.Metadata.GetDecodedPixelTypeInfo();
 
             foreach (ImageFrameMetadata frame in info.FrameMetadataCollection)
             {

src/ImageSharp/Formats/Jpeg/JpegDecoderCore.cs

@@ -226,7 +226,7 @@ public ImageInfo Identify(BufferedReadStream stream, CancellationToken cancellat
         this.InitDerivedMetadataProperties();
 
         Size pixelSize = this.Frame.PixelSize;
-        return new ImageInfo(new PixelTypeInfo(this.Frame.BitsPerPixel), new(pixelSize.Width, pixelSize.Height), this.Metadata);
+        return new ImageInfo(new(pixelSize.Width, pixelSize.Height), this.Metadata);
     }
 
     /// <summary>

src/ImageSharp/Formats/Pbm/PbmDecoderCore.cs

@@ -69,7 +69,7 @@ public Image<TPixel> Decode<TPixel>(BufferedReadStream stream, CancellationToken
     {
         this.ProcessHeader(stream);
 
-        var image = new Image<TPixel>(this.configuration, this.pixelSize.Width, this.pixelSize.Height, this.metadata);
+        Image<TPixel> image = new(this.configuration, this.pixelSize.Width, this.pixelSize.Height, this.metadata);
 
         Buffer2D<TPixel> pixels = image.GetRootFramePixelBuffer();
 
@@ -86,17 +86,17 @@ public Image<TPixel> Decode<TPixel>(BufferedReadStream stream, CancellationToken
     public ImageInfo Identify(BufferedReadStream stream, CancellationToken cancellationToken)
     {
         this.ProcessHeader(stream);
-
-        // BlackAndWhite pixels are encoded into a byte.
-        int bitsPerPixel = this.componentType == PbmComponentType.Short ? 16 : 8;
-        return new ImageInfo(new PixelTypeInfo(bitsPerPixel), new(this.pixelSize.Width, this.pixelSize.Height), this.metadata);
+        return new ImageInfo(
+            new(this.pixelSize.Width, this.pixelSize.Height),
+            this.metadata);
     }
 
     /// <summary>
     /// Processes the ppm header.
     /// </summary>
     /// <param name="stream">The input stream.</param>
     /// <exception cref="InvalidImageContentException">An EOF marker has been read before the image has been decoded.</exception>
+    [MemberNotNull(nameof(metadata))]
     private void ProcessHeader(BufferedReadStream stream)
     {
         Span<byte> buffer = stackalloc byte[2];

src/ImageSharp/Formats/Pbm/PbmMetadata.cs

@@ -97,20 +97,20 @@ public PixelTypeInfo GetPixelTypeInfo()
                 colorType = PixelColorType.Binary;
                 info = PixelComponentInfo.Create(1, bpp, 1);
                 break;
-            case PbmColorType.Grayscale:
-                bpp = 8;
-                colorType = PixelColorType.Luminance;
-                info = PixelComponentInfo.Create(1, bpp, 8);
-                break;
             case PbmColorType.Rgb:
-                bpp = 24;
+                bpp = this.ComponentType == PbmComponentType.Short ? 48 : 24;
                 colorType = PixelColorType.RGB;
-                info = PixelComponentInfo.Create(3, bpp, 8, 8, 8);
+                info = this.ComponentType == PbmComponentType.Short
+                    ? PixelComponentInfo.Create(3, bpp, 16, 16, 16)
+                    : PixelComponentInfo.Create(3, bpp, 8, 8, 8);
                 break;
+            case PbmColorType.Grayscale:
             default:
-                bpp = 8;
+                bpp = this.ComponentType == PbmComponentType.Short ? 16 : 8;
                 colorType = PixelColorType.Luminance;
-                info = PixelComponentInfo.Create(1, bpp, 8);
+                info = this.ComponentType == PbmComponentType.Short
+                    ? PixelComponentInfo.Create(1, bpp, bpp)
+                    : PixelComponentInfo.Create(1, bpp, bpp);
                 break;
         }
 

src/ImageSharp/Formats/Png/PngDecoderCore.cs

@@ -515,7 +515,7 @@ public ImageInfo Identify(BufferedReadStream stream, CancellationToken cancellat
             // Both PLTE and tRNS chunks, if present, have been read at this point as per spec.
             AssignColorPalette(this.palette, this.paletteAlpha, pngMetadata);
 
-            return new ImageInfo(new PixelTypeInfo(this.CalculateBitsPerPixel()), new(this.header.Width, this.header.Height), metadata);
+            return new ImageInfo(new(this.header.Width, this.header.Height), metadata);
         }
         finally
         {
@@ -680,29 +680,6 @@ private void InitializeFrame<TPixel>(
         this.scanline = this.configuration.MemoryAllocator.Allocate<byte>(this.bytesPerScanline, AllocationOptions.Clean);
     }
 
-    /// <summary>
-    /// Calculates the correct number of bits per pixel for the given color type.
-    /// </summary>
-    /// <returns>The <see cref="int"/></returns>
-    private int CalculateBitsPerPixel()
-    {
-        switch (this.pngColorType)
-        {
-            case PngColorType.Grayscale:
-            case PngColorType.Palette:
-                return this.header.BitDepth;
-            case PngColorType.GrayscaleWithAlpha:
-                return this.header.BitDepth * 2;
-            case PngColorType.Rgb:
-                return this.header.BitDepth * 3;
-            case PngColorType.RgbWithAlpha:
-                return this.header.BitDepth * 4;
-            default:
-                PngThrowHelper.ThrowNotSupportedColor();
-                return -1;
-        }
-    }
-
     /// <summary>
     /// Calculates the correct number of bytes per pixel for the given color type.
     /// </summary>

src/ImageSharp/Formats/Png/PngMetadata.cs

@@ -176,9 +176,9 @@ public PixelTypeInfo GetPixelTypeInfo()
                 break;
 
             case PngColorType.Grayscale:
-                bpp = 8;
+                bpp = (int)this.BitDepth;
                 colorType = PixelColorType.Luminance;
-                info = PixelComponentInfo.Create(1, bpp, 8);
+                info = PixelComponentInfo.Create(1, bpp, bpp);
                 break;
 
             case PngColorType.GrayscaleWithAlpha:
@@ -200,15 +200,15 @@ public PixelTypeInfo GetPixelTypeInfo()
             case PngColorType.Rgb:
                 if (this.BitDepth == PngBitDepth.Bit16)
                 {
-                    bpp = 24;
+                    bpp = 48;
                     colorType = PixelColorType.RGB;
-                    info = PixelComponentInfo.Create(3, bpp, 8, 8, 8);
+                    info = PixelComponentInfo.Create(3, bpp, 16, 16, 16);
                     break;
                 }
 
-                bpp = 48;
+                bpp = 24;
                 colorType = PixelColorType.RGB;
-                info = PixelComponentInfo.Create(3, bpp, 16, 16, 16);
+                info = PixelComponentInfo.Create(3, bpp, 8, 8, 8);
                 break;
 
             case PngColorType.RgbWithAlpha:

src/ImageSharp/Formats/Qoi/QoiDecoderCore.cs

@@ -73,7 +73,7 @@ public ImageInfo Identify(BufferedReadStream stream, CancellationToken cancellat
         qoiMetadata.Channels = this.header.Channels;
         qoiMetadata.ColorSpace = this.header.ColorSpace;
 
-        return new ImageInfo(pixelType, size, metadata);
+        return new ImageInfo(size, metadata);
     }
 
     /// <summary>

src/ImageSharp/Formats/Tga/TgaDecoderCore.cs

@@ -646,7 +646,6 @@ public ImageInfo Identify(BufferedReadStream stream, CancellationToken cancellat
     {
         this.ReadFileHeader(stream);
         return new ImageInfo(
-            new PixelTypeInfo(this.fileHeader.PixelDepth),
             new(this.fileHeader.Width, this.fileHeader.Height),
             this.metadata);
     }