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using MediaBrowser.Common.Drawing;
using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
using System.IO;
namespace MediaBrowser.Api
{
public static class ImageProcessor
{
/// <summary>
/// Resizes an image from a source stream and saves the result to an output stream
/// </summary>
/// <param name="width">Use if a fixed width is required. Aspect ratio will be preserved.</param>
/// <param name="height">Use if a fixed height is required. Aspect ratio will be preserved.</param>
/// <param name="maxWidth">Use if a max width is required. Aspect ratio will be preserved.</param>
/// <param name="maxHeight">Use if a max height is required. Aspect ratio will be preserved.</param>
/// <param name="quality">Quality level, from 0-100. Currently only applies to JPG. The default value should suffice.</param>
public static void ProcessImage(Stream sourceImageStream, Stream toStream, int? width, int? height, int? maxWidth, int? maxHeight, int? quality)
{
Image originalImage = Image.FromStream(sourceImageStream);
Size newSize = DrawingUtils.Resize(originalImage.Size, width, height, maxWidth, maxHeight);
Bitmap thumbnail;
// Graphics.FromImage will throw an exception if the PixelFormat is Indexed, so we need to handle that here
if (originalImage.PixelFormat.HasFlag(PixelFormat.Indexed))
{
thumbnail = new Bitmap(originalImage, newSize.Width, newSize.Height);
}
else
{
thumbnail = new Bitmap(newSize.Width, newSize.Height, originalImage.PixelFormat);
}
thumbnail.SetResolution(originalImage.HorizontalResolution, originalImage.VerticalResolution);
Graphics 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(originalImage, 0, 0, newSize.Width, newSize.Height);
Write(originalImage, thumbnail, toStream, quality);
thumbnailGraph.Dispose();
thumbnail.Dispose();
originalImage.Dispose();
}
private static void Write(Image originalImage, Image newImage, 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(originalImage.RawFormat))
{
SaveJpeg(newImage, toStream, quality);
}
else if (ImageFormat.Png.Equals(originalImage.RawFormat))
{
newImage.Save(toStream, ImageFormat.Png);
}
else
{
newImage.Save(toStream, originalImage.RawFormat);
}
}
private static void SaveJpeg(Image newImage, Stream target, int? quality)
{
if (!quality.HasValue)
{
quality = 90;
}
using (var encoderParameters = new EncoderParameters(1))
{
encoderParameters.Param[0] = new EncoderParameter(Encoder.Quality, quality.Value);
newImage.Save(target, GetImageCodeInfo("image/jpeg"), encoderParameters);
}
}
private static ImageCodecInfo GetImageCodeInfo(string mimeType)
{
ImageCodecInfo[] info = ImageCodecInfo.GetImageEncoders();
for (int i = 0; i < info.Length; i++)
{
ImageCodecInfo ici = info[i];
if (ici.MimeType.Equals(mimeType, StringComparison.OrdinalIgnoreCase))
{
return ici;
}
}
return info[1];
}
}
}
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