Config.Decoder: Introduces KeyFrameValidation which ensures no artifacts on some broken formats [Fixes #638]

Author: SuRGeoNix

FlyleafLib/Engine/Config.cs

@@ -565,6 +565,12 @@ public DecoderConfig Clone()
         public bool             ShowCorrupted       { get => _ShowCorrupted;        set => SetUI(ref _ShowCorrupted, value); }
         bool _ShowCorrupted;
 
+        /// <summary>
+        /// Ensures that after a key packet receives a also key frame (can create artifacts on some broken formats when disabled)
+        /// </summary>
+        public bool             KeyFrameValidation  { get => _KeyFrameValidation;   set => SetUI(ref _KeyFrameValidation, value); }
+        internal bool _KeyFrameValidation;
+
         /// <summary>
         /// Forces low delay (Parses AV_CODEC_FLAG2_FAST or AV_CODEC_FLAG_LOW_DELAY -based on DropFrames- to AVCodecContext) (auto-enabled with MaxLatency)
         /// </summary>

FlyleafLib/MediaFramework/MediaContext/DecoderContext.cs

@@ -531,7 +531,7 @@ public long GetVideoFrame(long timestamp = -1)
                 if (packet->flags.HasFlag(PktFlags.Key) || packet->pts == VideoDecoder.startPts)
                 {
                     VideoDecoder.keyPacketRequired = false;
-                    VideoDecoder.keyFrameRequired  = true;
+                    VideoDecoder.keyFrameRequired  = Config.Decoder._KeyFrameValidation;
                 }
                 else
                 {

FlyleafLib/MediaFramework/MediaDecoder/VideoDecoder.cs

@@ -493,7 +493,7 @@ protected override void RunInternal()
                 {
                     if (packet->flags.HasFlag(PktFlags.Key) || packet->pts == startPts)
                     {
-                        keyFrameRequired  = true;
+                        keyFrameRequired  = Config.Decoder._KeyFrameValidation;
                         keyPacketRequired = false;
                     }
                     else
@@ -1086,7 +1086,7 @@ public int DecodeFrameNext()
                 if (demuxer.packet->flags.HasFlag(PktFlags.Key) || demuxer.packet->pts == startPts)
                 {
                     keyPacketRequired = false;
-                    keyFrameRequired  = true;
+                    keyFrameRequired  = Config.Decoder._KeyFrameValidation;
                 }
                 else
                 {