1 files changed, 137 insertions, 0 deletions
diff --git a/MediaBrowser.Controller/FFMpeg/FFProbe.cs b/MediaBrowser.Controller/FFMpeg/FFProbe.cs
new file mode 100644
index 000000000..f16f0142d
--- /dev/null
+++ b/MediaBrowser.Controller/FFMpeg/FFProbe.cs
@@ -0,0 +1,137 @@
+using MediaBrowser.Common.Logging;
+using MediaBrowser.Common.Serialization;
+using MediaBrowser.Controller.Entities;
+using System;
+using System.Diagnostics;
+using System.IO;
+using System.Threading.Tasks;
+
+namespace MediaBrowser.Controller.FFMpeg
+{
+    /// <summary>
+    /// Runs FFProbe against a media file and returns metadata.
+    /// </summary>
+    public static class FFProbe
+    {
+        /// <summary>
+        /// Runs FFProbe against an Audio file, caches the result and returns the output
+        /// </summary>
+        public static FFProbeResult Run(BaseItem item, string cacheDirectory)
+        {
+            string cachePath = GetFfProbeCachePath(item, cacheDirectory);
+
+            // Use try catch to avoid having to use File.Exists
+            try
+            {
+                return GetCachedResult(cachePath);
+            }
+            catch (FileNotFoundException)
+            {
+            }
+            catch (Exception ex)
+            {
+                Logger.LogException(ex);
+            }
+
+            FFProbeResult result = Run(item.Path);
+
+            if (result != null)
+            {
+                // Fire and forget
+                CacheResult(result, cachePath);
+            }
+
+            return result;
+        }
+
+        /// <summary>
+        /// Gets the cached result of an FFProbe operation
+        /// </summary>
+        private static FFProbeResult GetCachedResult(string path)
+        {
+            return ProtobufSerializer.DeserializeFromFile<FFProbeResult>(path);
+        }
+
+        /// <summary>
+        /// Caches the result of an FFProbe operation
+        /// </summary>
+        private static async void CacheResult(FFProbeResult result, string outputCachePath)
+        {
+            await Task.Run(() =>
+            {
+                try
+                {
+                    ProtobufSerializer.SerializeToFile(result, outputCachePath);
+                }
+                catch (Exception ex)
+                {
+                    Logger.LogException(ex);
+                }
+            }).ConfigureAwait(false);
+        }
+
+        private static FFProbeResult Run(string input)
+        {
+            var startInfo = new ProcessStartInfo { };
+
+            startInfo.CreateNoWindow = true;
+
+            startInfo.UseShellExecute = false;
+
+            // Must consume both or ffmpeg may hang due to deadlocks. See comments below.
+            startInfo.RedirectStandardOutput = true;
+            startInfo.RedirectStandardError = true;
+
+            startInfo.FileName = Kernel.Instance.ApplicationPaths.FFProbePath;
+            startInfo.WorkingDirectory = Kernel.Instance.ApplicationPaths.FFMpegDirectory;
+            startInfo.Arguments = string.Format("\"{0}\" -v quiet -print_format json -show_streams -show_format", input);
+
+            //Logger.LogInfo(startInfo.FileName + " " + startInfo.Arguments);
+
+            var process = new Process { };
+            process.StartInfo = startInfo;
+
+            process.EnableRaisingEvents = true;
+
+            process.Exited += ProcessExited;
+
+            try
+            {
+                process.Start();
+
+                // MUST read both stdout and stderr asynchronously or a deadlock may occurr
+                // If we ever decide to disable the ffmpeg log then you must uncomment the below line.
+                process.BeginErrorReadLine();
+
+                return JsonSerializer.DeserializeFromStream<FFProbeResult>(process.StandardOutput.BaseStream);
+            }
+            catch (Exception ex)
+            {
+                Logger.LogException(ex);
+
+                // Hate having to do this
+                try
+                {
+                    process.Kill();
+                }
+                catch
+                {
+                }
+
+                return null;
+            }
+        }
+
+        static void ProcessExited(object sender, EventArgs e)
+        {
+            (sender as Process).Dispose();
+        }
+
+        private static string GetFfProbeCachePath(BaseItem item, string cacheDirectory)
+        {
+            string outputDirectory = Path.Combine(cacheDirectory, item.Id.ToString().Substring(0, 1));
+
+            return Path.Combine(outputDirectory, item.Id + "-" + item.DateModified.Ticks + ".pb");
+        }
+    }
+}