From 3efc34565a58523299a32069186467972012b491 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Patrick=20Kr=C3=A4mer?= <patagonahn@gmail.com>
Date: Wed, 7 Jul 2021 20:16:14 +0200
Subject: [PATCH] Support cancellation token for cancelling FFMPEG processes

---
 FFMpegCore.Test/VideoTest.cs                 | 60 ++++++++++++++++++++
 FFMpegCore/FFMpeg/FFMpegArgumentProcessor.cs |  5 ++
 2 files changed, 65 insertions(+)

diff --git a/FFMpegCore.Test/VideoTest.cs b/FFMpegCore.Test/VideoTest.cs
index 149dabd..2831084 100644
--- a/FFMpegCore.Test/VideoTest.cs
+++ b/FFMpegCore.Test/VideoTest.cs
@@ -12,6 +12,7 @@
 using FFMpegCore.Arguments;
 using FFMpegCore.Exceptions;
 using FFMpegCore.Pipes;
+using System.Threading;
 
 namespace FFMpegCore.Test
 {
@@ -612,5 +613,64 @@ public async Task Video_Cancel_Async_With_Timeout()
             Assert.AreEqual("h264", outputInfo.PrimaryVideoStream.CodecName);
             Assert.AreEqual("aac", outputInfo.PrimaryAudioStream!.CodecName);
         }
+
+        [TestMethod, Timeout(10000)]
+        public async Task Video_Cancel_CancellationToken_Async()
+        {
+            var outputFile = new TemporaryFile("out.mp4");
+
+            var cts = new CancellationTokenSource();
+
+            var task = FFMpegArguments
+                .FromFileInput("testsrc2=size=320x240[out0]; sine[out1]", false, args => args
+                    .WithCustomArgument("-re")
+                    .ForceFormat("lavfi"))
+                .OutputToFile(outputFile, false, opt => opt
+                    .WithAudioCodec(AudioCodec.Aac)
+                    .WithVideoCodec(VideoCodec.LibX264)
+                    .WithSpeedPreset(Speed.VeryFast))
+                .CancellableThrough(cts.Token)
+                .ProcessAsynchronously(false);
+
+            await Task.Delay(300);
+            cts.Cancel();
+
+            var result = await task;
+
+            Assert.IsFalse(result);
+        }
+
+        [TestMethod, Timeout(10000)]
+        public async Task Video_Cancel_CancellationToken_Async_With_Timeout()
+        {
+            var outputFile = new TemporaryFile("out.mp4");
+
+            var cts = new CancellationTokenSource();
+
+            var task = FFMpegArguments
+                .FromFileInput("testsrc2=size=320x240[out0]; sine[out1]", false, args => args
+                    .WithCustomArgument("-re")
+                    .ForceFormat("lavfi"))
+                .OutputToFile(outputFile, false, opt => opt
+                    .WithAudioCodec(AudioCodec.Aac)
+                    .WithVideoCodec(VideoCodec.LibX264)
+                    .WithSpeedPreset(Speed.VeryFast))
+                .CancellableThrough(cts.Token, 10000)
+                .ProcessAsynchronously(false);
+
+            await Task.Delay(300);
+            cts.Cancel();
+
+            var result = await task;
+
+            var outputInfo = await FFProbe.AnalyseAsync(outputFile);
+
+            Assert.IsTrue(result);
+            Assert.IsNotNull(outputInfo);
+            Assert.AreEqual(320, outputInfo.PrimaryVideoStream!.Width);
+            Assert.AreEqual(240, outputInfo.PrimaryVideoStream.Height);
+            Assert.AreEqual("h264", outputInfo.PrimaryVideoStream.CodecName);
+            Assert.AreEqual("aac", outputInfo.PrimaryAudioStream!.CodecName);
+        }
     }
 }
diff --git a/FFMpegCore/FFMpeg/FFMpegArgumentProcessor.cs b/FFMpegCore/FFMpeg/FFMpegArgumentProcessor.cs
index 67607af..060ffc3 100644
--- a/FFMpegCore/FFMpeg/FFMpegArgumentProcessor.cs
+++ b/FFMpegCore/FFMpeg/FFMpegArgumentProcessor.cs
@@ -50,6 +50,11 @@ public FFMpegArgumentProcessor CancellableThrough(out Action cancel, int timeout
             cancel = () => CancelEvent?.Invoke(this, timeout);
             return this;
         }
+        public FFMpegArgumentProcessor CancellableThrough(CancellationToken token, int timeout = 0)
+        {
+            token.Register(() => CancelEvent?.Invoke(this, timeout));
+            return this;
+        }
         public bool ProcessSynchronously(bool throwOnError = true, FFOptions? ffMpegOptions = null)
         {
             using var instance = PrepareInstance(ffMpegOptions ?? GlobalFFOptions.Current, out var cancellationTokenSource);