Ticket #12196: mythtv_fix_avf_bitrate.patch

mythtv/libs/libmythtv/avformatdecoder.cpp

@@ -90 +90 @@
 #define LOC QString("AFD: ")
 
 #define MAX_AC3_FRAME_SIZE 6144
+#define MAX_AVF_BIT_RATE 50000000
 
 static const float eps = 1E-5;
 
@@ -2509 +2510 @@
     if (ic && ((uint)ic->bit_rate > bitrate))
         bitrate = (uint)ic->bit_rate;
 
+    //If AVF uses PTS to calculate duration (and consequently bitrate)
+    //and there are glitches in the recording that reset the PTS near
+    //the end of the recording, the bitrate provided in ic->bit_rate
+    //will be much much higher than the actual bitrate of the recording.
+    //
+    //This can cause problems with the RingBuffer because the fill_min
+    //value will be set to a value larger than the buffer can hold, which
+    //will cause reads to never be allowed.
+    if ((uint)ic->bit_rate > MAX_AVF_BIT_RATE)
+        bitrate = MAX_AVF_BIT_RATE;
+
+
     if (bitrate > 0)
     {
         bitrate = (bitrate + 999) / 1000;