Adding transparent webp support

Former-commit-id: bde73846512628e8364d54420c2f1dac7af748e4

src/ImageProcessor.Web/NET45/HttpModules/ImageProcessingModule.cs

@@ -359,13 +359,14 @@ namespace ImageProcessor.Web.HttpModules
                 IPrincipal user = context.User ?? new GenericPrincipal(new GenericIdentity(string.Empty, string.Empty), new string[0]);
 
                 // Do we have permission to call UrlAuthorizationModule.CheckUrlAccessForPrincipal?
-                PermissionSet permission = new PermissionSet(PermissionState.None);
+                PermissionSet permission = new PermissionSet(PermissionState.Unrestricted);
                 permission.AddPermission(new AspNetHostingPermission(AspNetHostingPermissionLevel.Unrestricted));
                 bool hasPermission = permission.IsSubsetOf(AppDomain.CurrentDomain.PermissionSet);
                 
                 bool isAllowed = true;
 
-                // Run the rewritten path past the auth system again, using the result as the default "AllowAccess" value
+                // Run the rewritten path past the authorization system again.
+                // We can then use the result as the default "AllowAccess" value
                 if (hasPermission && !context.SkipAuthorization)
                 {
                     isAllowed = UrlAuthorizationModule.CheckUrlAccessForPrincipal(virtualCachedPath, user, "GET");

src/ImageProcessor/Imaging/Formats/WebPFormat.cs

@@ -13,6 +13,7 @@
 namespace ImageProcessor.Imaging.Formats
 {
     using System;
+    using System.Collections.Generic;
     using System.Diagnostics.CodeAnalysis;
     using System.Drawing;
     using System.Drawing.Imaging;
@@ -20,6 +21,8 @@ namespace ImageProcessor.Imaging.Formats
     using System.Runtime.InteropServices;
     using System.Text;
 
+    using ImageProcessor.Core.Common.Exceptions;
+
     /// <summary>
     /// Provides the necessary information to support webp images.
     /// Adapted from <see cref="http://groups.google.com/a/webmproject.org/forum/#!topic/webp-discuss/1coeidT0rQU"/>
@@ -72,6 +75,35 @@ namespace ImageProcessor.Imaging.Formats
             }
         }
 
+        /// <summary>
+        /// Applies the given processor the current image.
+        /// </summary>
+        /// <param name="processor">The processor delegate.</param>
+        /// <param name="factory">The <see cref="ImageFactory" />.</param>
+        public override void ApplyProcessor(Func<ImageFactory, Image> processor, ImageFactory factory)
+        {
+            base.ApplyProcessor(processor, factory);
+
+            // Set the property item information from any Exif metadata.
+            // We do this here so that they can be changed between processor methods.
+            if (factory.PreserveExifData)
+            {
+                foreach (KeyValuePair<int, PropertyItem> propertItem in factory.ExifPropertyItems)
+                {
+                    try
+                    {
+                        factory.Image.SetPropertyItem(propertItem.Value);
+                    }
+                    // ReSharper disable once EmptyGeneralCatchClause
+                    catch
+                    {
+                        // Do nothing. The image format does not handle EXIF data.
+                        // TODO: empty catch is fierce code smell.
+                    }
+                }
+            }
+        }
+
         /// <summary>
         /// Decodes the image to process.
         /// </summary>
@@ -151,49 +183,48 @@ namespace ImageProcessor.Imaging.Formats
             IntPtr ptrData = pinnedWebP.AddrOfPinnedObject();
             uint dataSize = (uint)webpData.Length;
 
-            int imgWidth;
-            int imgHeight;
+            int width;
+            int height;
 
-            if (WebPGetInfo(ptrData, dataSize, out imgWidth, out imgHeight) != 1)
+            if (WebPGetInfo(ptrData, dataSize, out width, out height) != 1)
             {
-                // TODO: Throw error?
-                return null;
+                throw new ImageFormatException("WebP image is corrupted.");
             }
 
             // Create a BitmapData and Lock all pixels to be written
-            Bitmap bmp = new Bitmap(imgWidth, imgHeight, PixelFormat.Format24bppRgb);
-            BitmapData bmpData = bmp.LockBits(new Rectangle(0, 0, bmp.Width, bmp.Height), ImageLockMode.WriteOnly, bmp.PixelFormat);
+            Bitmap bitmap = new Bitmap(width, height, PixelFormat.Format32bppArgb);
+            BitmapData bitmapData = bitmap.LockBits(new Rectangle(0, 0, bitmap.Width, bitmap.Height), ImageLockMode.WriteOnly, bitmap.PixelFormat);
 
             // Allocate memory for uncompress image
-            int outputBufferSize = bmpData.Stride * imgHeight;
+            int outputBufferSize = bitmapData.Stride * height;
             IntPtr outputBuffer = Marshal.AllocHGlobal(outputBufferSize);
 
             // Uncompress the image
-            outputBuffer = WebPDecodeBGRInto(ptrData, dataSize, outputBuffer, outputBufferSize, bmpData.Stride);
+            outputBuffer = WebPDecodeBGRAInto(ptrData, dataSize, outputBuffer, outputBufferSize, bitmapData.Stride);
 
             // Write image to bitmap using Marshal
             byte[] buffer = new byte[outputBufferSize];
             Marshal.Copy(outputBuffer, buffer, 0, outputBufferSize);
-            Marshal.Copy(buffer, 0, bmpData.Scan0, outputBufferSize);
+            Marshal.Copy(buffer, 0, bitmapData.Scan0, outputBufferSize);
 
             // Unlock the pixels
-            bmp.UnlockBits(bmpData);
+            bitmap.UnlockBits(bitmapData);
 
             // Free memory
             pinnedWebP.Free();
             Marshal.FreeHGlobal(outputBuffer);
 
-            return bmp;
+            return bitmap;
         }
 
         /// <summary>
-        /// Lossly encodes the image in bitmap.
+        /// Lossy encodes the image in bitmap.
         /// </summary>
         /// <param name="bitmap">
         /// Bitmap with the image
         /// </param>
         /// <param name="quality">
-        /// Quality. 0 = minimum ... 100 = maximimun quality
+        /// Quality. 0 = minimum ... 100 = maximum quality
         /// </param>
         /// <param name="webpData">
         /// The byte array containing the encoded image data.
@@ -207,9 +238,9 @@ namespace ImageProcessor.Imaging.Formats
 
             try
             {
-                BitmapData bmpData = bitmap.LockBits(new Rectangle(0, 0, bitmap.Width, bitmap.Height), ImageLockMode.ReadOnly, PixelFormat.Format24bppRgb);
+                BitmapData bmpData = bitmap.LockBits(new Rectangle(0, 0, bitmap.Width, bitmap.Height), ImageLockMode.ReadOnly, PixelFormat.Format32bppArgb);
                 IntPtr unmanagedData;
-                int size = WebPEncodeBGR(bmpData.Scan0, bitmap.Width, bitmap.Height, bmpData.Stride, quality, out unmanagedData);
+                int size = WebPEncodeBGRA(bmpData.Scan0, bitmap.Width, bitmap.Height, bmpData.Stride, quality, out unmanagedData);
 
                 // Copy image compress data to output array
                 webpData = new byte[size];
@@ -266,16 +297,16 @@ namespace ImageProcessor.Imaging.Formats
         /// Size of allocated buffer
         /// </param>
         /// <param name="outputStride">
-        /// Specifies the distance between scanlines
+        /// Specifies the distance between scan-lines
         /// </param>
         /// <returns>
         /// output_buffer if function succeeds; NULL otherwise
         /// </returns>
         [DllImport("libwebp.dll", CallingConvention = CallingConvention.Cdecl)]
-        private static extern IntPtr WebPDecodeBGRInto(IntPtr data, uint dataSize, IntPtr outputBuffer, int outputBufferSize, int outputStride);
+        private static extern IntPtr WebPDecodeBGRAInto(IntPtr data, uint dataSize, IntPtr outputBuffer, int outputBufferSize, int outputStride);
 
         /// <summary>
-        /// Lossless encoding images pointed to by *data in WebP format
+        /// Lossy encoding images pointed to by *data in WebP format
         /// </summary>
         /// <param name="rgb">
         /// Pointer to RGB image data
@@ -299,7 +330,7 @@ namespace ImageProcessor.Imaging.Formats
         /// Size of WebP Image
         /// </returns>
         [DllImport("libwebp.dll", CallingConvention = CallingConvention.Cdecl)]
-        private static extern int WebPEncodeBGR(IntPtr rgb, int width, int height, int stride, float qualityFactor, out IntPtr output);
+        private static extern int WebPEncodeBGRA(IntPtr rgb, int width, int height, int stride, float qualityFactor, out IntPtr output);
 
         /// <summary>
         /// Frees the unmanaged memory.

src/ImageProcessorConsole/Program.cs

@@ -10,8 +10,11 @@
 namespace ImageProcessorConsole
 {
     using System;
+    using System.Collections.Generic;
     using System.Drawing;
     using System.IO;
+    using System.Linq;
+
     using ImageProcessor;
     using ImageProcessor.Imaging.Formats;
 
@@ -37,8 +40,10 @@ namespace ImageProcessorConsole
                 di.Create();
             }
 
-            //FileInfo[] files = di.GetFiles("*.gif");
-            FileInfo[] files = di.GetFiles();
+            FileInfo[] files = di.GetFiles("*.jpg");
+            //FileInfo[] files = di.GetFiles();
+            //var files = GetFilesByExtensions(di, ".gif", ".webp");
+
 
             foreach (FileInfo fileInfo in files)
             {
@@ -47,20 +52,30 @@ namespace ImageProcessorConsole
                 // ImageProcessor
                 using (MemoryStream inStream = new MemoryStream(photoBytes))
                 {
-                    using (ImageFactory imageFactory = new ImageFactory())
+                    using (ImageFactory imageFactory = new ImageFactory(true))
                     {
                         Size size = new Size(200, 200);
 
                         // Load, resize, set the format and quality and save an image.
                         imageFactory.Load(inStream)
+                            .AutoRotate()
                             .Constrain(size)
-                            //.Format(new JpegFormat())
+                            .Format(new WebPFormat())
+                            .Quality(5)
                             // ReSharper disable once AssignNullToNotNullAttribute
-                            // .Save(Path.GetFullPath(Path.Combine(Path.GetDirectoryName(path), @"..\..\images\output", Path.GetFileNameWithoutExtension(fileInfo.Name) + ".jpg")));
-                            .Save(Path.GetFullPath(Path.Combine(Path.GetDirectoryName(path), @"..\..\images\output", fileInfo.Name)));
+                             .Save(Path.GetFullPath(Path.Combine(Path.GetDirectoryName(path), @"..\..\images\output", Path.GetFileNameWithoutExtension(fileInfo.Name) + ".webp")));
+                            //.Save(Path.GetFullPath(Path.Combine(Path.GetDirectoryName(path), @"..\..\images\output", fileInfo.Name)));
                     }
                 }
             }
         }
+
+        public static IEnumerable<FileInfo> GetFilesByExtensions(DirectoryInfo dir, params string[] extensions)
+        {
+            if (extensions == null)
+                throw new ArgumentNullException("extensions");
+            IEnumerable<FileInfo> files = dir.EnumerateFiles();
+            return files.Where(f => extensions.Contains(f.Extension, StringComparer.OrdinalIgnoreCase));
+        }
     }
 }

src/ImageProcessorConsole/images/input/circle.png

@@ -0,0 +1,3 @@
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+oid sha256:3df296a3fd58930899d308558b128db760879cb776afba8f2d6511aba3934dd0
+size 6957

src/ImageProcessorConsole/images/input/rotate.jpg.REMOVED.git-id

@@ -0,0 +1 @@
+406a6a7916628c0c0bea8243565a7162ebd5a505

src/ImageProcessorConsole/images/output/circle.webp

@@ -0,0 +1,3 @@
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+oid sha256:ac5bfc52fe066984db96d0b169a7fb7ebd76f3a1cf946ba02a167475377903c2
+size 1228

src/ImageProcessorConsole/images/output/rotate.webp

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:3543de5854cc0a8a95b5249548abc8150040542a127ac6d89eb6338b8dfa3a83
+size 1812