Improved FromBuffer() to accept Memory<byte> for better memory manage…

…ment (#316)

* Transformed FromBuffer() to FromMemory() for better memory management

* Kept FromBuffer naming + fixed a test

Whisper.net.Demo/Program.cs

@@ -9,7 +9,6 @@ await Parser.Default.ParseArguments<Options>(args)
     .WithParsedAsync(Demo);
 
 async Task Demo(Options opt)
-
 {
     if (!File.Exists(opt.ModelName))
     {

Whisper.net/Internals/ModelLoader/WhisperProcessorModelBufferLoader.cs → Whisper.net/Internals/ModelLoader/WhisperProcessorModelMemoryLoader.cs

@@ -1,41 +1,41 @@
 // Licensed under the MIT license: https://opensource.org/licenses/MIT
 
+using System.Buffers;
 using System.Runtime.InteropServices;
 using Whisper.net.Internals.Native;
 using Whisper.net.Native;
 
 namespace Whisper.net.Internals.ModelLoader;
 
-internal class WhisperProcessorModelBufferLoader : IWhisperProcessorModelLoader
+internal class WhisperProcessorModelMemoryLoader : IWhisperProcessorModelLoader
 {
-    private readonly GCHandle pinnedBuffer;
+    private readonly MemoryHandle pinnedMemory;
     private readonly WhisperAheads aHeads;
     private readonly GCHandle? aheadsHandle;
     private readonly UIntPtr bufferLength;
 
     private readonly WhisperFactoryOptions options;
 
-    public WhisperProcessorModelBufferLoader(byte[] buffer, WhisperFactoryOptions options)
+    public WhisperProcessorModelMemoryLoader(Memory<byte> buffer, WhisperFactoryOptions options)
     {
         this.options = options;
-
-        pinnedBuffer = GCHandle.Alloc(buffer, GCHandleType.Pinned);
+        pinnedMemory = buffer.Pin();
         aHeads = ModelLoaderUtils.GetWhisperAlignmentHeads(options.CustomAlignmentHeads, out aheadsHandle);
         bufferLength = new UIntPtr((uint)buffer.Length);
     }
 
     public void Dispose()
     {
-        pinnedBuffer.Free();
+        pinnedMemory.Dispose();
         if (aheadsHandle.HasValue)
         {
             aheadsHandle.Value.Free();
         }
     }
 
-    public IntPtr LoadNativeContext(INativeWhisper nativeWhisper)
+    public unsafe IntPtr LoadNativeContext(INativeWhisper nativeWhisper)
     {
-        return nativeWhisper.Whisper_Init_From_Buffer_With_Params_No_State(pinnedBuffer.AddrOfPinnedObject(), bufferLength,
+        return nativeWhisper.Whisper_Init_From_Buffer_With_Params_No_State((IntPtr)pinnedMemory.Pointer, bufferLength,
             new WhisperContextParams()
             {
                 UseGpu = options.UseGpu.AsByte(),

Whisper.net/WhisperFactory.cs

@@ -116,30 +116,30 @@ public static WhisperFactory FromPath(string path, WhisperFactoryOptions options
     }
 
     /// <summary>
-    /// Creates a factory that uses the ggml model from a buffer in order to create <seealso cref="WhisperProcessorBuilder"/>.
+    /// Creates a factory that uses the ggml model from a buffer in memory in order to create <seealso cref="WhisperProcessorBuilder"/>.
     /// </summary>
-    /// <param name="buffer">The buffer with the model.</param>
+    /// <param name="memory">The memory buffer with the model.</param>
     /// <returns>An instance to the same builder.</returns>
     /// <remarks>
     /// If you don't know where to find a ggml model, you can use <seealso cref="Ggml.WhisperGgmlDownloader"/> which is downloading a model from huggingface.co.
     /// </remarks>
-    public static WhisperFactory FromBuffer(byte[] buffer)
+    public static WhisperFactory FromBuffer(Memory<byte> memory)
     {
-        return FromBuffer(buffer, WhisperFactoryOptions.Default);
+        return FromBuffer(memory, WhisperFactoryOptions.Default);
     }
 
     /// <summary>
-    /// Creates a factory that uses the ggml model from a buffer in order to create <seealso cref="WhisperProcessorBuilder"/>.
+    /// Creates a factory that uses the ggml model from a buffer in memory in order to create <seealso cref="WhisperProcessorBuilder"/>.
     /// </summary>
-    /// <param name="buffer">The buffer with the model.</param>
+    /// <param name="memory">The memory buffer with the model.</param>
     /// <param name="options">Thhe options for the factory and the loading of the model.</param>
     /// <returns>An instance to the same builder.</returns>
     /// <remarks>
     /// If you don't know where to find a ggml model, you can use <seealso cref="Ggml.WhisperGgmlDownloader"/> which is downloading a model from huggingface.co.
     /// </remarks>
-    public static WhisperFactory FromBuffer(byte[] buffer, WhisperFactoryOptions options)
+    public static WhisperFactory FromBuffer(Memory<byte> memory, WhisperFactoryOptions options)
     {
-        return new WhisperFactory(new WhisperProcessorModelBufferLoader(buffer, options), options.DelayInitialization);
+        return new WhisperFactory(new WhisperProcessorModelMemoryLoader(memory, options), options.DelayInitialization);
     }
 
     /// <summary>

tests/Whisper.net.Maui.Tests/MainPage.xaml.cs

@@ -24,7 +24,7 @@ private async void ContentPage_Loaded(object sender, EventArgs e)
             await mauiStream.CopyToAsync(audioFileStream);
             audioFileStream.Seek(0, SeekOrigin.Begin);
 
-            using var whisperFactory = WhisperFactory.FromBuffer(memoryStream.ToArray());
+            using var whisperFactory = WhisperFactory.FromBuffer(memoryStream.GetBuffer().AsMemory(0, (int)memoryStream.Length));
             var whisperBuilder = whisperFactory.CreateBuilder();
             using var whisperProcessor = whisperBuilder.Build();
             LblResult.Text = string.Empty;

tests/Whisper.net.Tests/FactoryTests.cs

@@ -70,10 +70,10 @@ public void CreateBuilder_WithFileModel_ShouldReturnBuilder()
     }
 
     [Fact]
-    public void CreateBuilder_WithBufferedModel_ShouldReturnBuilder()
+    public void CreateBuilder_WithMemoryModel_ShouldReturnBuilder()
     {
-        var buffer = File.ReadAllBytes(model.ModelFile);
-        using var factory = WhisperFactory.FromBuffer(buffer);
+        var memoryBuffer = File.ReadAllBytes(model.ModelFile);
+        using var factory = WhisperFactory.FromBuffer(memoryBuffer);
         var builder = factory.CreateBuilder();
         builder.Should().NotBeNull();
     }