Fix the in-recording seektable for MPEG2-TS. Also, make the in-recording

seektable for MPEG2-PS better, although not yet quite correct.  In particular,
the file offsets are consistently earlier than they should be, but at least
this makes the previews functional.

The original issue seemed to be that we were recording the offest AFTER the
packet in question, rather than the offset at the beginning of the packet.  In
MPEG2-TS, due to the packetizing of the stream, it's easy to backtrack to the
beginning of the previous packet, but in MPEG2-PS, the frames are all of 
differing sizes, and I haven't quite got it tweaked right yet.

Refs #9256



git-svn-id: http://svn.mythtv.org/svn/trunk@27338 7dbf422c-18fa-0310-86e9-fd20926502f2

mythtv/libs/libmythtv/dtvrecorder.cpp

@@ -11,6 +11,7 @@
 #include "mpegstreamdata.h"
 #include "dtvrecorder.h"
 #include "tv_rec.h"
+#include "mythverbose.h"
 
 extern "C" {
 extern const uint8_t *ff_find_start_code(const uint8_t *p, const uint8_t *end, uint32_t *state);
@@ -329,7 +330,7 @@ bool DTVRecorder::FindMPEG2Keyframes(const TSPacket* tspacket)
     if (hasKeyFrame)
     {
         _last_keyframe_seen = _frames_seen_count;
-        HandleKeyframe();
+        HandleKeyframe(_frames_written_count, TSPacket::SIZE);
     }
 
     if (hasFrame)
@@ -388,7 +389,7 @@ bool DTVRecorder::FindAudioKeyframes(const TSPacket*)
         if (1 == (_frames_seen_count & 0x7))
         {
             _last_keyframe_seen = _frames_seen_count;
-            HandleKeyframe();
+            HandleKeyframe(_frames_written_count);
             hasKeyFrame = true;
         }
 
@@ -416,7 +417,7 @@ bool DTVRecorder::FindOtherKeyframes(const TSPacket *tspacket)
     _frames_written_count++;
     _last_keyframe_seen = _frames_seen_count;
 
-    HandleKeyframe();
+    HandleKeyframe(_frames_written_count);
 
     _has_written_other_keyframe = true;
 
@@ -451,12 +452,14 @@ void DTVRecorder::SetNextRecording(const ProgramInfo *progInf, RingBuffer *rb)
  *  \brief This save the current frame to the position maps
  *         and handles ringbuffer switching.
  */
-void DTVRecorder::HandleKeyframe(uint64_t extra)
+void DTVRecorder::HandleKeyframe(uint64_t frameNum, int64_t extra)
 {
     if (!ringBuffer)
         return;
 
+#if 0
     unsigned long long frameNum = _frames_written_count;
+#endif
 
     _first_keyframe = (_first_keyframe < 0) ? frameNum : _first_keyframe;
 
@@ -466,7 +469,7 @@ void DTVRecorder::HandleKeyframe(uint64_t extra)
     {
         long long startpos = ringBuffer->GetWritePosition();
         // FIXME: handle keyframes with start code spanning over two ts packets
-        startpos += _payload_buffer.size() + extra;
+        startpos += _payload_buffer.size() - extra;
 
         // Don't put negative offsets into the database, they get munged into
         // MAX_INT64 - offset, which is an exceedingly large number, and
@@ -773,19 +776,19 @@ void DTVRecorder::FindPSKeyFrames(const uint8_t *buffer, uint len)
             hasKeyFrame &= (_last_seq_seen + maxKFD) < _frames_seen_count;
         }
 
-        if (hasKeyFrame)
-        {
-            _last_keyframe_seen = _frames_seen_count;
-            HandleKeyframe(bufptr - bufstart);
-        }
-
         if (hasFrame)
         {
             _frames_seen_count++;
-            if (!_wait_for_keyframe_option || _first_keyframe>=0)
+            if (!_wait_for_keyframe_option || _first_keyframe >= 0)
                 _frames_written_count++;
         }
 
+        if (hasKeyFrame)
+        {
+            _last_keyframe_seen = _frames_seen_count;
+            HandleKeyframe(_frames_written_count, bufptr - bufstart);
+        }
+
         if ((aspectRatio > 0) && (aspectRatio != m_videoAspect))
         {
             m_videoAspect = aspectRatio;
@@ -846,6 +849,9 @@ void DTVRecorder::FindPSKeyFrames(const uint8_t *buffer, uint len)
     uint64_t rem = (bufend - bufstart);
     _payload_buffer.resize(idx + rem);
     memcpy(&_payload_buffer[idx], bufstart, rem);
+#if 0
+VERBOSE(VB_GENERAL, QString("idx: %1, rem: %2").arg(idx).arg(rem) );
+#endif
 }
 
 /* vim: set expandtab tabstop=4 shiftwidth=4: */

mythtv/libs/libmythtv/dtvrecorder.h

@@ -51,7 +51,7 @@ class DTVRecorder: public RecorderBase
     void FinishRecording(void);
     void ResetForNewFile(void);
 
-    void HandleKeyframe(uint64_t extra = 0);
+    void HandleKeyframe(uint64_t frameNum, int64_t extra = 0);
 
     void BufferedWrite(const TSPacket &tspacket);