Develop

examples-dotnet.sln

@@ -33,6 +33,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Examples.Concurrency.Tests"
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Examples.Xunit", "src\Examples.Xunit\Examples.Xunit.csproj", "{AF338717-EFC2-4DE9-8D7E-DD88F6C5C17E}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Examples.Graphics.Console", "src\Examples.Graphics.Console\Examples.Graphics.Console.csproj", "{83FE1916-A3C2-485F-A1DC-83C32F3CDD11}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -98,6 +100,10 @@ Global
 		{AF338717-EFC2-4DE9-8D7E-DD88F6C5C17E}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{AF338717-EFC2-4DE9-8D7E-DD88F6C5C17E}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{AF338717-EFC2-4DE9-8D7E-DD88F6C5C17E}.Release|Any CPU.Build.0 = Release|Any CPU
+		{83FE1916-A3C2-485F-A1DC-83C32F3CDD11}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{83FE1916-A3C2-485F-A1DC-83C32F3CDD11}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{83FE1916-A3C2-485F-A1DC-83C32F3CDD11}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{83FE1916-A3C2-485F-A1DC-83C32F3CDD11}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(NestedProjects) = preSolution
 		{CAE56FA8-47C5-4B1F-AB39-2F7D046A9021} = {016D6892-C42E-41BB-92C0-10AFDD607B64}
@@ -114,5 +120,6 @@ Global
 		{283EA675-8B59-4141-A7F3-90CFADAC33A8} = {016D6892-C42E-41BB-92C0-10AFDD607B64}
 		{6B2188FC-D14C-42D6-93A1-9CCB6FDFC104} = {016D6892-C42E-41BB-92C0-10AFDD607B64}
 		{AF338717-EFC2-4DE9-8D7E-DD88F6C5C17E} = {016D6892-C42E-41BB-92C0-10AFDD607B64}
+		{83FE1916-A3C2-485F-A1DC-83C32F3CDD11} = {016D6892-C42E-41BB-92C0-10AFDD607B64}
 	EndGlobalSection
 EndGlobal

src/Examples.Graphics.Console/Examples.Graphics.Console.csproj

@@ -0,0 +1,17 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net8.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <RootNamespace>Examples</RootNamespace>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="PDFiumSharpV2" Version="1.1.4" />
+    <PackageReference Include="SkiaSharp" Version="2.88.8" />
+    <PackageReference Include="SkiaSharp.NativeAssets.Linux" Version="2.88.8" />
+  </ItemGroup>
+
+</Project>

src/Examples.Graphics.Console/Graphics/ImageExtensions.cs

@@ -0,0 +1,27 @@
+namespace Examples.Graphics;
+
+public static class ImageExtensions
+{
+    public static string GetMimeType(this byte[] source)
+    {
+        var found = images.FirstOrDefault(x => source.Length > x.MagicNumber.Length
+                && x.MagicNumber.AsSpan().SequenceEqual(source.AsSpan()[..x.MagicNumber.Length])
+                );
+        if (found is not null)
+        {
+            return found.MimeType;
+        }
+
+        return "application/octet-stream";
+    }
+
+    private record Entry(string MimeType, byte[] MagicNumber);
+    private static readonly IEnumerable<Entry> images = [
+        new("image/jpeg", [0xff, 0xd8]),
+        new("image/png", [0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a]),
+        new("image/gif", [0x47, 0x49, 0x46, 0x38, 0x37, 0x61])
+
+    ];
+
+}
+

src/Examples.Graphics.Console/Graphics/PdfConvertor.cs

@@ -0,0 +1,84 @@
+using System.Runtime.InteropServices;
+using PDFiumSharp;
+using SkiaSharp;
+
+namespace Examples.Graphics;
+
+public class PdfConvertor
+{
+    private static readonly byte[] Header = [0x25, 0x50, 0x44, 0x46];
+
+    static PdfConvertor()
+    {
+        // ???
+
+        NativeLibrary.SetDllImportResolver(typeof(PDFium).Assembly, (name, assembly, searchPath) =>
+        {
+            IntPtr libHandle = IntPtr.Zero;
+
+            if (name == "pdfium_x64" && RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
+            {
+                if (!NativeLibrary.TryLoad("./runtimes/linux-x64/native/libpdfium.so",
+                    assembly,
+                    DllImportSearchPath.ApplicationDirectory,
+                    out libHandle))
+                {
+                    NativeLibrary.TryLoad("libpdfium.so",
+                     assembly,
+                     DllImportSearchPath.ApplicationDirectory,
+                     out libHandle);
+                }
+            }
+
+            return libHandle;
+        });
+    }
+
+
+    public static bool IsPdf(byte[] source)
+    {
+        return Header.AsSpan().SequenceEqual(source.AsSpan()[..Header.Length]);
+    }
+
+    public static ImageSource? ToPng(byte[] source)
+    {
+        if (!IsPdf(source)) { throw new ArgumentException($"{nameof(source)} is not PDF."); }
+
+        using var doc = new PdfDocument(source);
+        return ToImage(doc, SKEncodedImageFormat.Png);
+    }
+
+    public static ImageSource? ToJpeg(byte[] source, int quality)
+    {
+        if (!IsPdf(source)) { throw new ArgumentException($"{nameof(source)} is not PDF."); }
+
+        using var doc = new PdfDocument(source);
+        return ToImage(doc, SKEncodedImageFormat.Jpeg, quality);
+    }
+
+    public static ImageSource? ToImage(PdfDocument doc, SKEncodedImageFormat format, int quality = 100)
+    {
+        using var page = doc.Pages.FirstOrDefault();
+
+        var width = (int?)page?.Width ?? 640;
+        var height = (int?)page?.Height ?? 480;
+
+        using var bitmap = new PDFiumBitmap(width, height, hasAlpha: true);
+
+        bitmap.Fill(new PDFiumSharp.Types.FPDF_COLOR(255, 255, 255));
+        page?.Render(bitmap);
+
+        using var pixmap = new SKPixmap(
+            new(bitmap.Width, bitmap.Height, SKColorType.Bgra8888),
+            bitmap.Scan0,
+            bitmap.Stride);
+
+        using var encoded = pixmap.Encode(format, quality);
+
+        return new(encoded.ToArray(), pixmap.Width, pixmap.Height);
+    }
+
+    public record ImageSource(byte[] Data, double Width, double Height);
+
+
+}

src/Examples.Graphics.Console/Program.cs

@@ -0,0 +1,2 @@
+// See https://aka.ms/new-console-template for more information
+Console.WriteLine("Hello, World!");