Implement audio downmixing and ExtractFrames function

MediaToolkit src/MediaToolkit/CommandBuilder.cs

@@ -4,6 +4,7 @@
 using System;
 using System.Globalization;
 using System.Text;
+using System.IO;
 
 namespace MediaToolkit
 {
@@ -21,6 +22,8 @@ internal static string Serialize(EngineParameters engineParameters)
 
                 case FFmpegTask.GetThumbnail:
                     return GetThumbnail(engineParameters.InputFile, engineParameters.OutputFile, engineParameters.ConversionOptions);
+                case FFmpegTask.ExtractFrames:
+                    return ExtractFrames(engineParameters.InputFile);
                 default:
                     throw new ArgumentOutOfRangeException();
             }
@@ -42,6 +45,16 @@ private static string GetThumbnail(MediaFile inputFile, MediaFile outputFile, Co
 
             return commandBuilder.AppendFormat(" \"{0}\" ", outputFile.Filename).ToString();
         }
+
+        private static string ExtractFrames(MediaFile inputFile)
+        {
+            var commandBuilder = new StringBuilder();
+
+            commandBuilder.AppendFormat(" -i \"{0}\" ", inputFile.Filename);
+
+            return commandBuilder.AppendFormat(@" -r 1/1 " + Path.GetDirectoryName(inputFile.Filename) + "\\" + "frame%05d.jpg ").ToString();
+
+        }
 
         private static string Convert(MediaFile inputFile, MediaFile outputFile, ConversionOptions conversionOptions)
         {
@@ -79,6 +92,10 @@ private static string Convert(MediaFile inputFile, MediaFile outputFile, Convers
             // Audio sample rate
             if (conversionOptions.AudioSampleRate != AudioSampleRate.Default)
                 commandBuilder.AppendFormat(" -ar {0} ", conversionOptions.AudioSampleRate.Remove("Hz"));
+
+            //Audio downmix
+            if (conversionOptions.AudioDownmix)
+                commandBuilder.AppendFormat(" -ac 1 ");
 
             // Maximum video duration
             if (conversionOptions.MaxVideoDuration != null)

MediaToolkit src/MediaToolkit/Engine.cs

@@ -119,6 +119,20 @@ public void GetThumbnail(MediaFile inputFile, MediaFile outputFile, ConversionOp
             this.FFmpegEngine(engineParams);
         }
 
+         /// -------------------------------------------------------------------------------------------------
+        /// <summary>   Extracts all frames from a video. </summary>
+        /// <param name="inputFile">    Video file. </param>
+        public void ExtractFrames(MediaFile inputFile)
+        {
+            EngineParameters engineParams = new EngineParameters
+            {
+                InputFile = inputFile,
+                Task = FFmpegTask.ExtractFrames
+            };
+
+            this.FFmpegEngine(engineParams);
+        }
+
         #region Private method - Helpers
 
         private void FFmpegEngine(EngineParameters engineParameters)
@@ -303,4 +317,4 @@ private void StartFFmpegProcess(EngineParameters engineParameters)
             }
         }
     }
-}
+}

MediaToolkit src/MediaToolkit/FFmpegTask.cs

@@ -11,6 +11,9 @@ internal enum FFmpegTask
         GetMetaData,
 
         /// <summary>   An enum constant representing the get thumbnail option. </summary>
-        GetThumbnail
+        GetThumbnail,
+
+        /// <summary>   An enum constant representing the extract frames option. </summary>
+        ExtractFrames
     }
-}
+}

MediaToolkit src/MediaToolkit/Options/ConversionOptions.cs

@@ -38,6 +38,11 @@ public void CutMedia(TimeSpan seekToPosition, TimeSpan length)
         ///     Audio sample rate
         /// </summary>
         public AudioSampleRate AudioSampleRate = AudioSampleRate.Default;
+
+        /// <summary>
+        ///     Audio sample rate
+        /// </summary>
+        public bool AudioDownmix = false;
 
         /// <summary>
         ///     The maximum duration
@@ -101,4 +106,4 @@ public void CutMedia(TimeSpan seekToPosition, TimeSpan length)
         public bool BaselineProfile { get; set; }
     }
 
-}
+}