Fix crash on MediaTek PAL Android TVs

app/src/main/java/com/limelight/Game.java

@@ -329,13 +329,21 @@ public class Game extends Activity implements SurfaceHolder.Callback,
         // Hopefully, we can get rid of this once someone comes up with a better way
         // to track the state of the pipeline and time frames.
         int roundedRefreshRate = Math.round(displayRefreshRate);
-        if (roundedRefreshRate <= 49) {
-            // Let's avoid clearly bogus refresh rates
-            roundedRefreshRate = 60;
-        }
         if (!prefConfig.disableFrameDrop && prefConfig.fps >= roundedRefreshRate) {
-            prefConfig.fps = roundedRefreshRate - 1;
+            if (roundedRefreshRate <= 49) {
-            LimeLog.info("Adjusting FPS target for screen to "+prefConfig.fps);
+                // Let's avoid clearly bogus refresh rates and fall back to legacy rendering
+                decoderRenderer.enableLegacyFrameDropRendering();
+                LimeLog.info("Bogus refresh rate: "+roundedRefreshRate);
+            }
+            // HACK: Avoid crashing on some MTK devices
+            else if (roundedRefreshRate == 50 && decoderRenderer.is49FpsBlacklisted()) {
+                // Use the old rendering strategy on these broken devices
+                decoderRenderer.enableLegacyFrameDropRendering();
+            }
+            else {
+                prefConfig.fps = roundedRefreshRate - 1;
+                LimeLog.info("Adjusting FPS target for screen to "+prefConfig.fps);
+            }
         }
 
         StreamConfiguration config = new StreamConfiguration.Builder()

app/src/main/java/com/limelight/binding/video/MediaCodecDecoderRenderer.java

@@ -56,6 +56,7 @@ public class MediaCodecDecoderRenderer extends VideoDecoderRenderer {
     private int consecutiveCrashCount;
     private String glRenderer;
     private boolean foreground = true;
+    private boolean legacyFrameDropRendering = false;
 
     private boolean needsBaselineSpsHack;
     private SeqParameterSet savedSps;
@@ -191,6 +192,15 @@ public class MediaCodecDecoderRenderer extends VideoDecoderRenderer {
         return avcDecoder != null;
     }
 
+    public boolean is49FpsBlacklisted() {
+        return avcDecoder != null && MediaCodecHelper.decoderBlacklistedFor49Fps(avcDecoder.getName());
+    }
+
+    public void enableLegacyFrameDropRendering() {
+        LimeLog.info("Legacy frame drop rendering enabled");
+        legacyFrameDropRendering = true;
+    }
+
     public boolean isHevcMain10Hdr10Supported() {
         if (hevcDecoder == null) {
             return false;
@@ -410,7 +420,7 @@ public class MediaCodecDecoderRenderer extends VideoDecoderRenderer {
                             }
 
                             // Render the last buffer
-                            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
+                            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP && !legacyFrameDropRendering) {
                                 // Use a PTS that will cause this frame to never be dropped if frame dropping
                                 // is disabled
                                 videoDecoder.releaseOutputBuffer(lastIndex, 0);

app/src/main/java/com/limelight/binding/video/MediaCodecHelper.java

@@ -36,6 +36,7 @@ public class MediaCodecHelper {
 	private static final List<String> whitelistedHevcDecoders;
 	private static final List<String> refFrameInvalidationAvcPrefixes;
     private static final List<String> refFrameInvalidationHevcPrefixes;
+    private static final List<String> blacklisted49FpsDecoderPrefixes;
 
     private static boolean isLowEndSnapdragon = false;
     private static boolean initialized = false;
@@ -153,6 +154,17 @@ public class MediaCodecHelper {
 		// Qualcomm is currently the only decoders in this group.
 	}
 
+	static {
+		blacklisted49FpsDecoderPrefixes = new LinkedList<>();
+
+		// We see a bunch of crashes on MediaTek Android TVs running
+		// at 49 FPS (PAL 50 Hz - 1). Blacklist this frame rate for
+		// these devices and hope they fix it in Oreo.
+		if (Build.VERSION.SDK_INT < Build.VERSION_CODES.O) {
+			blacklisted49FpsDecoderPrefixes.add("omx.mtk");
+		}
+	}
+
 	private static String getAdrenoVersionString(String glRenderer) {
 		glRenderer = glRenderer.toLowerCase().trim();
 
@@ -271,7 +283,7 @@ public class MediaCodecHelper {
 	public static long getMonotonicMillis() {
 		return System.nanoTime() / 1000000L;
 	}
-	
+
 	public static boolean decoderSupportsAdaptivePlayback(MediaCodecInfo decoderInfo) {
 		// Possibly enable adaptive playback on KitKat and above
 		if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
@@ -312,6 +324,10 @@ public class MediaCodecHelper {
         return isDecoderInList(baselineProfileHackPrefixes, decoderName);
     }
 
+	public static boolean decoderBlacklistedFor49Fps(String decoderName) {
+		return isDecoderInList(blacklisted49FpsDecoderPrefixes, decoderName);
+	}
+
 	public static boolean decoderSupportsRefFrameInvalidationAvc(String decoderName, int videoHeight) {
 		// Reference frame invalidation is broken on low-end Snapdragon SoCs at 1080p.
 		if (videoHeight > 720 && isLowEndSnapdragon) {