using System; using System.Drawing; using System.Drawing.Drawing2D; using System.Drawing.Imaging; using System.IO; using System.Linq; namespace MediaBrowser.Controller.Drawing { /// /// Class ImageExtensions /// public static class ImageExtensions { /// /// Saves the image. /// /// The output format. /// The image. /// To stream. /// The quality. public static void Save(this Image image, ImageFormat outputFormat, Stream toStream, int quality) { // Use special save methods for jpeg and png that will result in a much higher quality image // All other formats use the generic Image.Save if (ImageFormat.Jpeg.Equals(outputFormat)) { SaveAsJpeg(image, toStream, quality); } else if (ImageFormat.Png.Equals(outputFormat)) { image.Save(toStream, ImageFormat.Png); } else { image.Save(toStream, outputFormat); } } /// /// Saves the JPEG. /// /// The image. /// The target. /// The quality. public static void SaveAsJpeg(this Image image, Stream target, int quality) { using (var encoderParameters = new EncoderParameters(1)) { encoderParameters.Param[0] = new EncoderParameter(Encoder.Quality, quality); image.Save(target, GetImageCodecInfo("image/jpeg"), encoderParameters); } } private static readonly ImageCodecInfo[] Encoders = ImageCodecInfo.GetImageEncoders(); /// /// Gets the image codec info. /// /// Type of the MIME. /// ImageCodecInfo. private static ImageCodecInfo GetImageCodecInfo(string mimeType) { return Encoders.FirstOrDefault(i => i.MimeType.Equals(mimeType, StringComparison.OrdinalIgnoreCase)) ?? Encoders.FirstOrDefault(); } /// /// Determines whether [is pixel format supported by graphics object] [the specified format]. /// /// The format. /// true if [is pixel format supported by graphics object] [the specified format]; otherwise, false. public static bool IsPixelFormatSupportedByGraphicsObject(PixelFormat format) { // http://msdn.microsoft.com/en-us/library/system.drawing.graphics.fromimage.aspx if (format.HasFlag(PixelFormat.Indexed)) { return false; } if (format.HasFlag(PixelFormat.Undefined)) { return false; } if (format.HasFlag(PixelFormat.DontCare)) { return false; } if (format.HasFlag(PixelFormat.Format16bppArgb1555)) { return false; } if (format.HasFlag(PixelFormat.Format16bppGrayScale)) { return false; } return true; } /// /// Crops an image by removing whitespace and transparency from the edges /// /// The BMP. /// Bitmap. /// public static Bitmap CropWhitespace(this Bitmap bmp) { var width = bmp.Width; var height = bmp.Height; var topmost = 0; for (int row = 0; row < height; ++row) { if (IsAllWhiteRow(bmp, row, width)) topmost = row; else break; } int bottommost = 0; for (int row = height - 1; row >= 0; --row) { if (IsAllWhiteRow(bmp, row, width)) bottommost = row; else break; } int leftmost = 0, rightmost = 0; for (int col = 0; col < width; ++col) { if (IsAllWhiteColumn(bmp, col, height)) leftmost = col; else break; } for (int col = width - 1; col >= 0; --col) { if (IsAllWhiteColumn(bmp, col, height)) rightmost = col; else break; } if (rightmost == 0) rightmost = width; // As reached left if (bottommost == 0) bottommost = height; // As reached top. var croppedWidth = rightmost - leftmost; var croppedHeight = bottommost - topmost; if (croppedWidth == 0) // No border on left or right { leftmost = 0; croppedWidth = width; } if (croppedHeight == 0) // No border on top or bottom { topmost = 0; croppedHeight = height; } // Graphics.FromImage will throw an exception if the PixelFormat is Indexed, so we need to handle that here var thumbnail = bmp.PixelFormat.HasFlag(PixelFormat.Indexed) ? new Bitmap(croppedWidth, croppedHeight) : new Bitmap(croppedWidth, croppedHeight, bmp.PixelFormat); // Preserve the original resolution thumbnail.SetResolution(bmp.HorizontalResolution, bmp.VerticalResolution); using (var thumbnailGraph = Graphics.FromImage(thumbnail)) { thumbnailGraph.CompositingQuality = CompositingQuality.HighQuality; thumbnailGraph.SmoothingMode = SmoothingMode.HighQuality; thumbnailGraph.InterpolationMode = InterpolationMode.HighQualityBicubic; thumbnailGraph.PixelOffsetMode = PixelOffsetMode.HighQuality; thumbnailGraph.CompositingMode = CompositingMode.SourceOver; thumbnailGraph.DrawImage(bmp, new RectangleF(0, 0, croppedWidth, croppedHeight), new RectangleF(leftmost, topmost, croppedWidth, croppedHeight), GraphicsUnit.Pixel); } return thumbnail; } /// /// Determines whether or not a row of pixels is all whitespace /// /// The BMP. /// The row. /// The width. /// true if [is all white row] [the specified BMP]; otherwise, false. private static bool IsAllWhiteRow(Bitmap bmp, int row, int width) { for (var i = 0; i < width; ++i) { if (!IsWhiteSpace(bmp.GetPixel(i, row))) { return false; } } return true; } /// /// Determines whether or not a column of pixels is all whitespace /// /// The BMP. /// The col. /// The height. /// true if [is all white column] [the specified BMP]; otherwise, false. private static bool IsAllWhiteColumn(Bitmap bmp, int col, int height) { for (var i = 0; i < height; ++i) { if (!IsWhiteSpace(bmp.GetPixel(col, i))) { return false; } } return true; } /// /// Determines if a color is whitespace /// /// The color. /// true if [is white space] [the specified color]; otherwise, false. private static bool IsWhiteSpace(Color color) { return (color.R == 255 && color.G == 255 && color.B == 255) || color.A == 0; } } }