SkiaSharp based TIFf to PDF poc

Author: seeste

GithubActionsHelloWorld/GithubActionsHelloWorld.csproj

@@ -20,8 +20,9 @@
 	</PropertyGroup>
 
 	<ItemGroup>
+		<PackageReference Include="BitMiracle.LibTiff.NET" Version="2.4.649" />
 		<PackageReference Include="PdfSharpCore" Version="1.3.40" />
-		<PackageReference Include="SixLabors.ImageSharp" Version="2.1.3" />
+		<PackageReference Include="SkiaSharp" Version="2.88.2" />
 	</ItemGroup>
 
 </Project>

GithubActionsHelloWorld/Program.cs

@@ -1,9 +1,12 @@
-using PdfSharpCore.Drawing;
+using BitMiracle.LibTiff.Classic;
+using PdfSharpCore.Drawing;
 using PdfSharpCore.Fonts;
 using PdfSharpCore.Pdf;
 using PdfSharpCore.Utils;
-using SixLabors.ImageSharp;
+using SkiaSharp;
+using System.Collections.Generic;
 using System.IO;
+using System.Runtime.InteropServices;
 using System.Threading.Tasks;
 
 namespace GithubActionsHelloWorld
@@ -15,17 +18,22 @@ public static async Task Main(string[] args)
             GlobalFontSettings.FontResolver = new FontResolver();
 
             var document = new PdfDocument();
+            var fileStream = File.OpenRead(args[0]); ;
 
-            using (var tiff = Image.Load(args[0]))
+            var pageImages = tiffToBitmap(args[0]);
+            for (int pageIndex = 0; pageIndex < pageImages.Count; pageIndex++)
 
-                for (var pageIndex = 0; pageIndex < tiff.Frames.Count; pageIndex++)
-                {
-                    var pageImage = await ConvertToXImageAsync(tiff.Frames.CloneFrame(pageIndex));
-                    var pageWithImage = new PdfPage();
-                    document.Pages.Add(pageWithImage);
-                    var xgr = XGraphics.FromPdfPage(document.Pages[pageIndex]);
-                    xgr.DrawImage(pageImage, 0, 0);
-                }
+            {
+                var pageWithImage = new PdfPage();
+                document.Pages.Add(pageWithImage);
+                var xgr = XGraphics.FromPdfPage(document.Pages[pageIndex]);
+
+                //    var memorystream = new MemoryStream(pageImage.Bytes);
+                //memorystream.Position = 0;
+                //var xImage = XImage.FromStream(() => memorystream);
+                var xImage = XImage.FromStream(() => File.OpenRead(pageImages[pageIndex]));
+                xgr.DrawImage(xImage, 0, 0);
+            }
 
             var page = document.AddPage();
             var gfx = XGraphics.FromPdfPage(page);
@@ -40,13 +48,109 @@ public static async Task Main(string[] args)
             document.Save("helloworld.pdf");
         }
 
-        private static async Task<XImage> ConvertToXImageAsync(Image imageFrame)
+        private static List<string> tiffToBitmap(string fileName)
+        {
+            var tempPaths = new List<string>();
+
+            using var tiff = Tiff.Open(fileName, "r");
+
+            var numberIfTiffPages = getNumberofTiffPages(tiff);
+
+            for (short i = 0; i < numberIfTiffPages; i++)
+            {
+                tiff.SetDirectory(i);
+
+                // read the dimensions
+                var width = tiff.GetField(TiffTag.IMAGEWIDTH)[0].ToInt();
+                var height = tiff.GetField(TiffTag.IMAGELENGTH)[0].ToInt();
+
+                // create the bitmap
+                var bitmap = new SKBitmap();
+                var info = new SKImageInfo(width, height);
+
+                // create the buffer that will hold the pixels
+                var raster = new int[width * height];
+
+                // get a pointer to the buffer, and give it to the bitmap
+                var ptr = GCHandle.Alloc(raster, GCHandleType.Pinned);
+                bitmap.InstallPixels(info, ptr.AddrOfPinnedObject(), info.RowBytes, null, (addr, ctx) => ptr.Free(), null);
+
+                // read the image into the memory buffer
+                if (!tiff.ReadRGBAImageOriented(width, height, raster, Orientation.TOPLEFT))
+                {
+                    // not a valid TIF image.
+                    return null;
+                }
+
+                // swap the red and blue because SkiaSharp may differ from the tiff
+                if (SKImageInfo.PlatformColorType == SKColorType.Bgra8888)
+                {
+                    SKSwizzle.SwapRedBlue(ptr.AddrOfPinnedObject(), raster.Length);
+                }
+
+                var encodedData = bitmap.Encode(SKEncodedImageFormat.Png, 100);
+
+                var tempPath = Path.Combine(Path.GetTempFileName() + ".png");
+                using var bitmapImageStream = File.Open(tempPath, FileMode.Create, FileAccess.Write, FileShare.None);
+                encodedData.SaveTo(bitmapImageStream);
+                tempPaths.Add(tempPath);
+            }
+            return tempPaths;
+        }
+
+        public static int getNumberofTiffPages(Tiff image)
+        {
+            int pageCount = 0;
+            do
+            {
+                ++pageCount;
+            } while (image.ReadDirectory());
+
+            return pageCount;
+        }
+
+        public static SKBitmap OpenTiff(Stream tiffStream)
         {
-            using var memoryStream = new MemoryStream();
-            await imageFrame.SaveAsPngAsync(memoryStream);
-            memoryStream.Position = 0;
-            var image = XImage.FromStream(() => memoryStream);
-            return image;
+            // https://stackoverflow.com/questions/50312937/skiasharp-tiff-support
+
+            tiffStream.Position = 0;
+            // open a TIFF stored in the stream
+            using (var tifImg = Tiff.ClientOpen("in-memory", "r", tiffStream, new TiffStream()))
+            {
+                tifImg.SetDirectory(1);
+
+                // read the dimensions
+                var width = tifImg.GetField(TiffTag.IMAGEWIDTH)[0].ToInt();
+                var height = tifImg.GetField(TiffTag.IMAGELENGTH)[0].ToInt();
+
+                // create the bitmap
+                var bitmap = new SKBitmap();
+                var info = new SKImageInfo(width, height);
+
+                // create the buffer that will hold the pixels
+                var raster = new int[width * height];
+
+                // get a pointer to the buffer, and give it to the bitmap
+                var ptr = GCHandle.Alloc(raster, GCHandleType.Pinned);
+                bitmap.InstallPixels(info, ptr.AddrOfPinnedObject(), info.RowBytes, null, (addr, ctx) => ptr.Free(), null);
+
+                // read the image into the memory buffer
+                if (!tifImg.ReadRGBAImageOriented(width, height, raster, Orientation.TOPLEFT, true))
+                {
+                    // not a valid TIF image.
+                    return null;
+                }
+
+                // swap the red and blue because SkiaSharp may differ from the tiff
+                if (SKImageInfo.PlatformColorType == SKColorType.Bgra8888)
+                {
+                    SKSwizzle.SwapRedBlue(ptr.AddrOfPinnedObject(), raster.Length);
+                }
+
+                File.WriteAllBytes("test.bmp", bitmap.Bytes);
+
+                return bitmap;
+            }
         }
     }
 }