Ticket #4515: write_dsmcc_packets_where_no_AV_packets.diff

libs/libmythtv/dtvrecorder.cpp

@@ -38 +38 @@
     // used for scanning pes headers for keyframes
     _start_code(0xffffffff),        _first_keyframe(-1),
     _last_gop_seen(0),              _last_seq_seen(0),
-    _last_keyframe_seen(0),
+    _last_keyframe_seen(0),         _hasWrittenOtherKeyFrame(false),
     // H.264 support
     _pes_synced(false),
     _seen_sps(false),
@@ -146 +146 @@
 
     //_start_code
     _first_keyframe             =-1;
+    _hasWrittenOtherKeyFrame    = false;
     _last_keyframe_seen         = 0;
     _last_gop_seen              = 0;
     _last_seq_seen              = 0;
@@ -344 +345 @@
     return hasKeyFrame;
 }
 
+// Non-Audio/Video data. For streams which contain no audio/video, write just 1 key-frame
+// at the start.
+bool DTVRecorder::FindOtherKeyframes(const TSPacket *tspacket)
+{
+    if (_hasWrittenOtherKeyFrame)
+        return true;
+
+    VERBOSE(VB_RECORD, LOC + "DSMCC - FindOtherKeyframes() - generating initial key-frame");
+    _frames_seen_count++;
+    _frames_written_count++;
+    _last_keyframe_seen = _frames_seen_count;
+    HandleKeyframe();
+    _hasWrittenOtherKeyFrame = true;
+    return true;
+}
+
 // documented in recorderbase.h
 void DTVRecorder::SetNextRecording(const ProgramInfo *progInf, RingBuffer *rb)
 {

libs/libmythtv/dvbrecorder.cpp

@@ -477 +477 @@
 
 bool DVBRecorder::ProcessVideoTSPacket(const TSPacket &tspacket)
 {
+    VERBOSE(VB_RECORD, LOC + "DSMCC - ProcessVideoTSPacket()");
     uint streamType = _stream_id[tspacket.PID()];
 
     // Check for keyframes and count frames
@@ -491 +492 @@
         _buffer_packets = !FindMPEG2Keyframes(&tspacket);
     }
 
-    return ProcessTSPacket(tspacket);
+    return ProcessAVTSPacket(tspacket);
 }
 
 bool DVBRecorder::ProcessAudioTSPacket(const TSPacket &tspacket)
 {
+    VERBOSE(VB_RECORD, LOC + "DSMCC - ProcessAudioTSPacket()");
     _buffer_packets = !FindAudioKeyframes(&tspacket);
-    return ProcessTSPacket(tspacket);
+    return ProcessAVTSPacket(tspacket);
 }
 
-bool DVBRecorder::ProcessTSPacket(const TSPacket &tspacket)
+// Common code for processing either audio or video packets
+bool DVBRecorder::ProcessAVTSPacket(const TSPacket &tspacket)
 {
-    const uint pid = tspacket.PID();
 
-    // Check continuity counter
-    if ((pid != 0x1fff) && !CheckCC(pid, tspacket.ContinuityCounter()))
-    {
-        VERBOSE(VB_RECORD, LOC +
-                QString("PID 0x%1 discontinuity detected").arg(pid,0,16));
-        _continuity_error_count++;
-    }
-
     // Sync recording start to first keyframe
+    // (Delay's until first GOP to avoid decoder crash on res change)
     if (_wait_for_keyframe_option && _first_keyframe < 0)
+    {
+        VERBOSE(VB_RECORD, LOC + QString("DSMCC - ProcessAVTSPacket() - Ignoring packet"));
         return true;
+    }
 
+    const uint pid = tspacket.PID();
     // Sync streams to the first Payload Unit Start Indicator
     // _after_ first keyframe iff _wait_for_keyframe_option is true
     if (!(_pid_status[pid] & kPayloadStartSeen) && tspacket.HasPayload())
     {
         if (!tspacket.PayloadStart())
+        {
+            VERBOSE(VB_RECORD, LOC + "DSMCC - ProcessAVTSPacket() - Not PayloadStart - dropping packet");
             return true; // not payload start - drop packet
+        }
 
         VERBOSE(VB_RECORD,
                 QString("PID 0x%1 Found Payload Start").arg(pid,0,16));
@@ -529 +531 @@
         _pid_status[pid] |= kPayloadStartSeen;
     }
 
+    return ProcessTSPacketCommon(tspacket);
+}
+
+bool DVBRecorder::ProcessTSPacket(const TSPacket &tspacket)
+{
+    VERBOSE(VB_RECORD, LOC + "DSMCC - ProcessTSPacket()");
+    _buffer_packets = !FindOtherKeyframes(&tspacket);
+    return ProcessTSPacketCommon(tspacket);
+}
+
+bool DVBRecorder::ProcessTSPacketCommon(const TSPacket &tspacket)
+{
+    // Care must be taken to make sure that the packet actually gets written
+    // as the decision to actually write it has already been made
+    const uint pid = tspacket.PID();
+    VERBOSE(VB_RECORD, LOC + QString("DSMCC - ProcessTSPacketCommon() Started (PID: 0x%1)").arg(pid,0,16));
+
+    // Check continuity counter
+    if ((pid != 0x1fff) && !CheckCC(pid, tspacket.ContinuityCounter()))
+    {
+        VERBOSE(VB_RECORD, LOC +
+                QString("PID 0x%1 discontinuity detected").arg(pid,0,16));
+        _continuity_error_count++;
+    }
+
     BufferedWrite(tspacket);
 
     return true;
 }
+
+void DVBRecorder::BufferedWrite(const TSPacket &tspacket)
+{
+    VERBOSE(VB_RECORD, LOC + QString("DSMCC - BufferedWrite() - buffer: %1").arg(_buffer_packets));
+    // Care must be taken to make sure that the packet actually gets written
+    // as the decision to actually write it has already been made
+
+    // Do we have to buffer the packet for exact keyframe detection?
+    if (_buffer_packets)
+    {
+        int idx = _payload_buffer.size();
+        _payload_buffer.resize(idx + TSPacket::SIZE);
+        memcpy(&_payload_buffer[idx], tspacket.data(), TSPacket::SIZE);
+        return;
+    }
+
+    // We are free to write the packet, but if we have buffered packet[s]
+    // we have to write them first...
+    if (!_payload_buffer.empty())
+    {
+        if (ringBuffer)
+            ringBuffer->Write(&_payload_buffer[0], _payload_buffer.size());
+        _payload_buffer.clear();
+    }
+
+    if (ringBuffer)
+        ringBuffer->Write(tspacket.data(), TSPacket::SIZE);
+}
+