/// <summary> /// Encodes the image to the specified stream from the <see cref="ImageFrame{TPixel}"/>. /// </summary> /// <typeparam name="TPixel">The pixel format.</typeparam> /// <param name="image">The <see cref="ImageFrame{TPixel}"/> to encode from.</param> /// <param name="stream">The <see cref="Stream"/> to encode the image data to.</param> public void Encode <TPixel>(Image <TPixel> image, Stream stream) where TPixel : unmanaged, IPixel <TPixel> { Guard.NotNull(image, nameof(image)); Guard.NotNull(stream, nameof(stream)); this.configuration = image.GetConfiguration(); ImageMetadata metadata = image.Metadata; BmpMetadata bmpMetadata = metadata.GetBmpMetadata(); this.bitsPerPixel = this.bitsPerPixel ?? bmpMetadata.BitsPerPixel; short bpp = (short)this.bitsPerPixel; int bytesPerLine = 4 * (((image.Width * bpp) + 31) / 32); this.padding = bytesPerLine - (int)(image.Width * (bpp / 8F)); // Set Resolution. int hResolution = 0; int vResolution = 0; if (metadata.ResolutionUnits != PixelResolutionUnit.AspectRatio) { if (metadata.HorizontalResolution > 0 && metadata.VerticalResolution > 0) { switch (metadata.ResolutionUnits) { case PixelResolutionUnit.PixelsPerInch: hResolution = (int)Math.Round(UnitConverter.InchToMeter(metadata.HorizontalResolution)); vResolution = (int)Math.Round(UnitConverter.InchToMeter(metadata.VerticalResolution)); break; case PixelResolutionUnit.PixelsPerCentimeter: hResolution = (int)Math.Round(UnitConverter.CmToMeter(metadata.HorizontalResolution)); vResolution = (int)Math.Round(UnitConverter.CmToMeter(metadata.VerticalResolution)); break; case PixelResolutionUnit.PixelsPerMeter: hResolution = (int)Math.Round(metadata.HorizontalResolution); vResolution = (int)Math.Round(metadata.VerticalResolution); break; } } } int infoHeaderSize = this.writeV4Header ? BmpInfoHeader.SizeV4 : BmpInfoHeader.SizeV3; var infoHeader = new BmpInfoHeader( headerSize: infoHeaderSize, height: image.Height, width: image.Width, bitsPerPixel: bpp, planes: 1, imageSize: image.Height * bytesPerLine, clrUsed: 0, clrImportant: 0, xPelsPerMeter: hResolution, yPelsPerMeter: vResolution); if (this.writeV4Header && this.bitsPerPixel == BmpBitsPerPixel.Pixel32) { infoHeader.AlphaMask = Rgba32AlphaMask; infoHeader.RedMask = Rgba32RedMask; infoHeader.GreenMask = Rgba32GreenMask; infoHeader.BlueMask = Rgba32BlueMask; infoHeader.Compression = BmpCompression.BitFields; } int colorPaletteSize = this.bitsPerPixel == BmpBitsPerPixel.Pixel8 ? ColorPaletteSize8Bit : 0; var fileHeader = new BmpFileHeader( type: BmpConstants.TypeMarkers.Bitmap, fileSize: BmpFileHeader.Size + infoHeaderSize + infoHeader.ImageSize, reserved: 0, offset: BmpFileHeader.Size + infoHeaderSize + colorPaletteSize); Span <byte> buffer = stackalloc byte[infoHeaderSize]; fileHeader.WriteTo(buffer); stream.Write(buffer, 0, BmpFileHeader.Size); if (this.writeV4Header) { infoHeader.WriteV4Header(buffer); } else { infoHeader.WriteV3Header(buffer); } stream.Write(buffer, 0, infoHeaderSize); this.WriteImage(stream, image.Frames.RootFrame); stream.Flush(); }