Workaround for missing PNG compression in SkiaSharp 3.x

sungaila · Sep 21, 2024 · 512c9f6 · 512c9f6
1 parent 5a59bee
commit 512c9f6
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Showing 10 changed files with 72 additions and 28 deletions.
diff --git a/src/PDFtoImage/Conversion.Base64.cs b/src/PDFtoImage/Conversion.Base64.cs
@@ -1,4 +1,5 @@
-using SkiaSharp;
+using PDFtoImage.Internals;
+using SkiaSharp;
 using System;
 using System.Collections.Generic;
 using System.Drawing;
@@ -294,7 +295,7 @@ internal static void SaveImpl(Stream imageStream, SKEncodedImageFormat format, s
                 throw new ArgumentNullException(nameof(imageStream));
 
             using var bitmap = ToImage(pdfAsBase64String, page, password, options);
-            bitmap.Encode(imageStream, format, 100);
+            bitmap.EncodeExt(imageStream, format, 100);
         }
 #endif
     }

diff --git a/src/PDFtoImage/Conversion.ByteArray.cs b/src/PDFtoImage/Conversion.ByteArray.cs
@@ -1,4 +1,5 @@
-using SkiaSharp;
+using PDFtoImage.Internals;
+using SkiaSharp;
 using System;
 using System.Collections.Generic;
 using System.Drawing;
@@ -324,7 +325,7 @@ internal static void SaveImpl(Stream imageStream, SKEncodedImageFormat format, b
                 throw new ArgumentNullException(nameof(imageStream));
 
             using var bitmap = ToImage(pdfAsByteArray, page, password, options);
-            bitmap.Encode(imageStream, format, 100);
+            bitmap.EncodeExt(imageStream, format, 100);
         }
 #endif
     }

diff --git a/src/PDFtoImage/Conversion.Deprecated.cs b/src/PDFtoImage/Conversion.Deprecated.cs
@@ -456,7 +456,7 @@ internal static void SaveImpl(string filename, SKEncodedImageFormat format, Stre
         internal static void SaveImpl(Stream stream, SKEncodedImageFormat format, Stream pdfStream, bool leaveOpen = false, string? password = null, int page = 0, RenderOptions options = default)
         {
             using var bitmap = ToImage(pdfStream, leaveOpen, password, page, options);
-            bitmap.Encode(stream, format, 100);
+            bitmap.EncodeExt(stream, format, 100);
         }
 
 #if NET6_0_OR_GREATER
@@ -480,7 +480,7 @@ internal static void SaveImpl(Stream imageStream, SKEncodedImageFormat format, b
                 throw new ArgumentNullException(nameof(imageStream));
 
             using var bitmap = ToImage(pdfAsByteArray, password, page, options);
-            bitmap.Encode(imageStream, format, 100);
+            bitmap.EncodeExt(imageStream, format, 100);
         }
 
 #if NET6_0_OR_GREATER
@@ -504,7 +504,7 @@ internal static void SaveImpl(Stream imageStream, SKEncodedImageFormat format, s
                 throw new ArgumentNullException(nameof(imageStream));
 
             using var bitmap = ToImage(pdfAsBase64String, password, page, options);
-            bitmap.Encode(imageStream, format, 100);
+            bitmap.EncodeExt(imageStream, format, 100);
         }
     }
 }
diff --git a/src/PDFtoImage/Conversion.Stream.cs b/src/PDFtoImage/Conversion.Stream.cs
@@ -355,7 +355,7 @@ internal static void SaveImpl(string filename, SKEncodedImageFormat format, Stre
         internal static void SaveImpl(Stream stream, SKEncodedImageFormat format, Stream pdfStream, Index page, bool leaveOpen = false, string? password = null, RenderOptions options = default)
         {
             using var bitmap = ToImage(pdfStream, page, leaveOpen, password, options);
-            bitmap.Encode(stream, format, 100);
+            bitmap.EncodeExt(stream, format, 100);
         }
 #endif
     }

diff --git a/src/PDFtoImage/Internals/SKBitmapExtensions.cs b/src/PDFtoImage/Internals/SKBitmapExtensions.cs
@@ -0,0 +1,28 @@
+using SkiaSharp;
+using System;
+using System.IO;
+
+namespace PDFtoImage.Internals
+{
+    internal static class SKBitmapExtensions
+    {
+        [Obsolete("This is a workaround for the missing PNG compression in SkiaSharp 3.x. Remove this once SkiaSharp is fixed.")]
+        public static bool EncodeExt(this SKBitmap bitmap, Stream dst, SKEncodedImageFormat format, int quality)
+        {
+            if (format == SKEncodedImageFormat.Png)
+            {
+                using var pixmap = new SKPixmap(bitmap.Info, bitmap.GetPixels());
+                using var data = pixmap.Encode(SKPngEncoderOptions.Default);
+
+                if (data == null)
+                    return false;
+
+                data.SaveTo(dst);
+
+                return true;
+            }
+
+            return bitmap.Encode(dst, format, quality);
+        }
+    }
+}
diff --git a/src/PDFtoImage/PDFtoImage.csproj b/src/PDFtoImage/PDFtoImage.csproj
@@ -105,6 +105,16 @@
     <PackageReference Include="Sungaila.PDFium.BlazorWebAssembly" Version="131.0.6728" PrivateAssets="analyzers" />
   </ItemGroup>
 
+  <!-- allow Tests project to access internals -->
+  <ItemGroup>
+    <AssemblyAttribute Include="System.Runtime.CompilerServices.InternalsVisibleToAttribute">
+      <_Parameter1>PDFtoImage.Tests</_Parameter1>
+    </AssemblyAttribute>
+    <AssemblyAttribute Include="System.Runtime.CompilerServices.InternalsVisibleToAttribute">
+      <_Parameter1>PDFtoImage.WebConverter</_Parameter1>
+    </AssemblyAttribute>
+  </ItemGroup>
+
   <Import Project="PDFtoImage.PropertiesSigning.targets" />
   <Import Project="PDFtoImage.CodeSigning.targets" />
   <Import Project="PDFtoImage.PackageSigning.targets" />

diff --git a/src/Tests/AspectRatioTests.cs b/src/Tests/AspectRatioTests.cs
@@ -1,4 +1,5 @@
 using Microsoft.VisualStudio.TestTools.UnitTesting;
+using PDFtoImage.Internals;
 using PDFtoImage.Tests;
 using System.IO;
 using static PDFtoImage.Conversion;
@@ -352,7 +353,7 @@ public void IgnoreDpi(string fileName, int? width = null, int? height = null, bo
             {
                 using var outputStream = CreateOutputStream(expectedPath);
 
-                ToImage(inputStream, true, options: new(Dpi: i, Width: width, Height: height, WithAnnotations: true, WithFormFill: true, WithAspectRatio: withAspectRatio)).Encode(outputStream, SkiaSharp.SKEncodedImageFormat.Jpeg, 100);
+                ToImage(inputStream, true, options: new(Dpi: i, Width: width, Height: height, WithAnnotations: true, WithFormFill: true, WithAspectRatio: withAspectRatio)).EncodeExt(outputStream, SkiaSharp.SKEncodedImageFormat.Jpeg, 100);
                 CompareStreams(expectedPath, outputStream);
             }
         }
@@ -375,8 +376,8 @@ public void IgnoreAspectRatio(string fileName, int width, int height)
             using var outputStream1 = CreateOutputStream(expectedPath);
             using var outputStream2 = CreateOutputStream(expectedPath);
 
-            ToImage(inputStream, true, options: new(Width: width, Height: height, WithAnnotations: true, WithFormFill: true, WithAspectRatio: false)).Encode(outputStream1, SkiaSharp.SKEncodedImageFormat.Jpeg, 100);
-            ToImage(inputStream, true, options: new(Width: width, Height: height, WithAnnotations: true, WithFormFill: true, WithAspectRatio: true)).Encode(outputStream2, SkiaSharp.SKEncodedImageFormat.Jpeg, 100);
+            ToImage(inputStream, true, options: new(Width: width, Height: height, WithAnnotations: true, WithFormFill: true, WithAspectRatio: false)).EncodeExt(outputStream1, SkiaSharp.SKEncodedImageFormat.Jpeg, 100);
+            ToImage(inputStream, true, options: new(Width: width, Height: height, WithAnnotations: true, WithFormFill: true, WithAspectRatio: true)).EncodeExt(outputStream2, SkiaSharp.SKEncodedImageFormat.Jpeg, 100);
 
             CompareStreams(expectedPath, outputStream1);
             CompareStreams(expectedPath, outputStream2);
@@ -400,8 +401,8 @@ public void IgnoreAspectRatioWithDpi(string fileName, int dpi)
             using var outputStream1 = CreateOutputStream(expectedPath);
             using var outputStream2 = CreateOutputStream(expectedPath);
 
-            ToImage(inputStream, true, options: new(Dpi: dpi, WithAnnotations: true, WithFormFill: true, WithAspectRatio: false)).Encode(outputStream1, SkiaSharp.SKEncodedImageFormat.Jpeg, 100);
-            ToImage(inputStream, true, options: new(Dpi: dpi, WithAnnotations: true, WithFormFill: true, WithAspectRatio: true)).Encode(outputStream2, SkiaSharp.SKEncodedImageFormat.Jpeg, 100);
+            ToImage(inputStream, true, options: new(Dpi: dpi, WithAnnotations: true, WithFormFill: true, WithAspectRatio: false)).EncodeExt(outputStream1, SkiaSharp.SKEncodedImageFormat.Jpeg, 100);
+            ToImage(inputStream, true, options: new(Dpi: dpi, WithAnnotations: true, WithFormFill: true, WithAspectRatio: true)).EncodeExt(outputStream2, SkiaSharp.SKEncodedImageFormat.Jpeg, 100);
 
             CompareStreams(expectedPath, outputStream1);
             CompareStreams(expectedPath, outputStream2);

diff --git a/src/Tests/BatchingTests.cs b/src/Tests/BatchingTests.cs
@@ -1,4 +1,5 @@
 using Microsoft.VisualStudio.TestTools.UnitTesting;
+using PDFtoImage.Internals;
 using PDFtoImage.Tests;
 using SkiaSharp;
 using System;
@@ -62,7 +63,7 @@ public void ToImagesWithSelectionOdd()
             {
                 var expectedPath = Path.Combine("..", "Assets", "Expected", GetPlatformAsString(), $"Wikimedia_Commons_web_{selection[i]}.png");
                 using var outputStream = CreateOutputStream(expectedPath);
-                bitmap.Encode(outputStream, SKEncodedImageFormat.Png, 100);
+                bitmap.EncodeExt(outputStream, SKEncodedImageFormat.Png, 100);
 
                 CompareStreams(expectedPath, outputStream);
                 i++;
@@ -150,7 +151,7 @@ public void ToImagesWithRangeAll()
             {
                 var expectedPath = Path.Combine("..", "Assets", "Expected", GetPlatformAsString(), $"Wikimedia_Commons_web_{i}.png");
                 using var outputStream = CreateOutputStream(expectedPath);
-                bitmap.Encode(outputStream, SKEncodedImageFormat.Png, 100);
+                bitmap.EncodeExt(outputStream, SKEncodedImageFormat.Png, 100);
 
                 CompareStreams(expectedPath, outputStream);
                 i++;
@@ -170,7 +171,7 @@ public void ToImagesWithRangeSecondHalf()
             {
                 var expectedPath = Path.Combine("..", "Assets", "Expected", GetPlatformAsString(), $"Wikimedia_Commons_web_{i}.png");
                 using var outputStream = CreateOutputStream(expectedPath);
-                bitmap.Encode(outputStream, SKEncodedImageFormat.Png, 100);
+                bitmap.EncodeExt(outputStream, SKEncodedImageFormat.Png, 100);
 
                 CompareStreams(expectedPath, outputStream);
                 i++;
@@ -190,7 +191,7 @@ public void ToImagesWithSelectionEven()
             {
                 var expectedPath = Path.Combine("..", "Assets", "Expected", GetPlatformAsString(), $"Wikimedia_Commons_web_{selection[i]}.png");
                 using var outputStream = CreateOutputStream(expectedPath);
-                bitmap.Encode(outputStream, SKEncodedImageFormat.Png, 100);
+                bitmap.EncodeExt(outputStream, SKEncodedImageFormat.Png, 100);
 
                 CompareStreams(expectedPath, outputStream);
                 i++;
@@ -210,7 +211,7 @@ public async Task ToImagesWithRangeAllAsync()
             {
                 var expectedPath = Path.Combine("..", "Assets", "Expected", GetPlatformAsString(), $"Wikimedia_Commons_web_{i}.png");
                 using var outputStream = CreateOutputStream(expectedPath);
-                bitmap.Encode(outputStream, SKEncodedImageFormat.Png, 100);
+                bitmap.EncodeExt(outputStream, SKEncodedImageFormat.Png, 100);
 
                 CompareStreams(expectedPath, outputStream);
                 i++;
@@ -230,7 +231,7 @@ public async Task ToImagesWithRangeSecondHalfAsync()
             {
                 var expectedPath = Path.Combine("..", "Assets", "Expected", GetPlatformAsString(), $"Wikimedia_Commons_web_{i}.png");
                 using var outputStream = CreateOutputStream(expectedPath);
-                bitmap.Encode(outputStream, SKEncodedImageFormat.Png, 100);
+                bitmap.EncodeExt(outputStream, SKEncodedImageFormat.Png, 100);
 
                 CompareStreams(expectedPath, outputStream);
                 i++;
@@ -250,7 +251,7 @@ public async Task ToImagesWithSelectionEvenAsync()
             {
                 var expectedPath = Path.Combine("..", "Assets", "Expected", GetPlatformAsString(), $"Wikimedia_Commons_web_{selection[i]}.png");
                 using var outputStream = CreateOutputStream(expectedPath);
-                bitmap.Encode(outputStream, SKEncodedImageFormat.Png, 100);
+                bitmap.EncodeExt(outputStream, SKEncodedImageFormat.Png, 100);
 
                 CompareStreams(expectedPath, outputStream);
                 i++;
@@ -270,7 +271,7 @@ public async Task ToImagesWithSelectionOddAsync()
             {
                 var expectedPath = Path.Combine("..", "Assets", "Expected", GetPlatformAsString(), $"Wikimedia_Commons_web_{selection[i]}.png");
                 using var outputStream = CreateOutputStream(expectedPath);
-                bitmap.Encode(outputStream, SKEncodedImageFormat.Png, 100);
+                bitmap.EncodeExt(outputStream, SKEncodedImageFormat.Png, 100);
 
                 CompareStreams(expectedPath, outputStream);
                 i++;

diff --git a/src/Tests/ComparisonTests.cs b/src/Tests/ComparisonTests.cs
@@ -1,4 +1,5 @@
 using Microsoft.VisualStudio.TestTools.UnitTesting;
+using PDFtoImage.Internals;
 using PDFtoImage.Tests;
 using SkiaSharp;
 using System;
@@ -82,7 +83,7 @@ public void SaveWebpPages(bool withAnnotations = false)
                 var expectedPath = Path.Combine("..", "Assets", "Expected", GetPlatformAsString(), $"Wikimedia_Commons_web_{page}{(withAnnotations ? "_ANNOT" : string.Empty)}.webp");
 
                 using var outputStream = CreateOutputStream(expectedPath);
-                image.Encode(outputStream, SKEncodedImageFormat.Webp, 100);
+                image.EncodeExt(outputStream, SKEncodedImageFormat.Webp, 100);
 
                 CompareStreams(expectedPath, outputStream);
 
@@ -105,7 +106,7 @@ public async Task SaveWebpPagesAsync(bool withAnnotations = false)
                 var expectedPath = Path.Combine("..", "Assets", "Expected", GetPlatformAsString(), $"Wikimedia_Commons_web_{page}{(withAnnotations ? "_ANNOT" : string.Empty)}.webp");
 
                 using var outputStream = CreateOutputStream(expectedPath);
-                image.Encode(outputStream, SKEncodedImageFormat.Webp, 100);
+                image.EncodeExt(outputStream, SKEncodedImageFormat.Webp, 100);
 
                 CompareStreams(expectedPath, outputStream);
 
@@ -181,7 +182,7 @@ public void SavePngPages(bool withAnnotations = false)
                 var expectedPath = Path.Combine("..", "Assets", "Expected", GetPlatformAsString(), $"Wikimedia_Commons_web_{page}{(withAnnotations ? "_ANNOT" : string.Empty)}.png");
 
                 using var outputStream = CreateOutputStream(expectedPath);
-                image.Encode(outputStream, SKEncodedImageFormat.Png, 100);
+                image.EncodeExt(outputStream, SKEncodedImageFormat.Png, 100);
 
                 CompareStreams(expectedPath, outputStream);
 
@@ -204,7 +205,7 @@ public async Task SavePngPagesAsync(bool withAnnotations = false)
                 var expectedPath = Path.Combine("..", "Assets", "Expected", GetPlatformAsString(), $"Wikimedia_Commons_web_{page}{(withAnnotations ? "_ANNOT" : string.Empty)}.png");
 
                 using var outputStream = CreateOutputStream(expectedPath);
-                image.Encode(outputStream, SKEncodedImageFormat.Png, 100);
+                image.EncodeExt(outputStream, SKEncodedImageFormat.Png, 100);
 
                 CompareStreams(expectedPath, outputStream);
 
@@ -280,7 +281,7 @@ public void SaveJpegPages(bool withAnnotations = false)
                 var expectedPath = Path.Combine("..", "Assets", "Expected", GetPlatformAsString(), $"Wikimedia_Commons_web_{page}{(withAnnotations ? "_ANNOT" : string.Empty)}.jpg");
 
                 using var outputStream = CreateOutputStream(expectedPath);
-                image.Encode(outputStream, SKEncodedImageFormat.Jpeg, 100);
+                image.EncodeExt(outputStream, SKEncodedImageFormat.Jpeg, 100);
 
                 CompareStreams(expectedPath, outputStream);
 
@@ -303,7 +304,7 @@ public async Task SaveJpegPagesAsync(bool withAnnotations = false)
                 var expectedPath = Path.Combine("..", "Assets", "Expected", GetPlatformAsString(), $"Wikimedia_Commons_web_{page}{(withAnnotations ? "_ANNOT" : string.Empty)}.jpg");
 
                 using var outputStream = CreateOutputStream(expectedPath);
-                image.Encode(outputStream, SKEncodedImageFormat.Jpeg, 100);
+                image.EncodeExt(outputStream, SKEncodedImageFormat.Jpeg, 100);
 
                 CompareStreams(expectedPath, outputStream);
 

diff --git a/src/WebConverter/Pages/Index.razor.cs b/src/WebConverter/Pages/Index.razor.cs
@@ -1,6 +1,7 @@
 using Microsoft.AspNetCore.Components.Forms;
 using Microsoft.Extensions.Logging;
 using Microsoft.JSInterop;
+using PDFtoImage.Internals;
 using PDFtoImage.WebConverter.Models;
 using SkiaSharp;
 using System;
@@ -182,7 +183,7 @@ await Task.Factory.StartNew(() =>
                             DpiRelativeToBounds: Model.DpiRelativeToBounds
                         )
                     );
-                    encodeSuccess = bitmap!.Encode(Model.Output, Model.Format, Model.Quality);
+                    encodeSuccess = bitmap!.EncodeExt(Model.Output, Model.Format, Model.Quality);
                 }, TaskCreationOptions.LongRunning);
 
                 if (!encodeSuccess)