Fixed detecting frames in case the Picture Start Code or Access Unit Delimiter extends over TS packet boundaries (cont'd)

HISTORY

@@ -6634,6 +6634,9 @@ Video Disk Recorder Revision History
   channel is being received with.
 - Fixed detecting frames in case the Picture Start Code or Access Unit Delimiter
   extends over TS packet boundaries (reported by Johan Andersson).
+  In order to fix this, the semantics of cFrameDetector had to be changed a little.
+  See cRecorder::Action() and cIndexFileGenerator::Action() on how to use the new
+  cFrameDetector::NewPayload() function.
 - The frame detector now only starts collecting PTS values after it has seen the
   first I-frame, otherwise it might get MaxPtsValues values and stop analyzing
   even though the incoming data is still garbage (reported by Derek Kelly).

recorder.c

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: recorder.c 2.9 2010/12/27 11:35:46 kls Exp $
+ * $Id: recorder.c 2.10 2011/06/12 13:35:20 kls Exp $
  */
 
 #include "recorder.h"
@@ -31,7 +31,7 @@ cRecorder::cRecorder(const char *FileName, const cChannel *Channel, int Priority
 
   SpinUpDisk(FileName);
 
-  ringBuffer = new cRingBufferLinear(RECORDERBUFSIZE, MIN_TS_PACKETS_FOR_FRAME_DETECTOR * TS_SIZE, true, "Recorder");
+  ringBuffer = new cRingBufferLinear(RECORDERBUFSIZE, TS_SIZE, true, "Recorder");
   ringBuffer->SetTimeouts(0, 100);
 
   int Pid = Channel->Vpid();
@@ -119,6 +119,8 @@ void cRecorder::Action(void)
   time_t t = time(NULL);
   bool InfoWritten = false;
   bool FirstIframeSeen = false;
+  int FileNumber = 0;
+  off_t FrameOffset = -1;
   while (Running()) {
         int r;
         uchar *b = ringBuffer->Get(r);
@@ -139,12 +141,16 @@ void cRecorder::Action(void)
                        }
                     InfoWritten = true;
                     }
+                 if (frameDetector->NewPayload()) {
+                    FileNumber = fileName->Number();
+                    FrameOffset = fileSize;
+                    }
                  if (FirstIframeSeen || frameDetector->IndependentFrame()) {
                     FirstIframeSeen = true; // start recording with the first I-frame
                     if (!NextFile())
                        break;
                     if (index && frameDetector->NewFrame())
-                       index->Write(frameDetector->IndependentFrame(), fileName->Number(), fileSize);
+                       index->Write(frameDetector->IndependentFrame(), FileNumber, FrameOffset);
                     if (frameDetector->IndependentFrame()) {
                        recordFile->Write(patPmtGenerator.GetPat(), TS_SIZE);
                        fileSize += TS_SIZE;

recording.c

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: recording.c 2.30 2011/04/17 13:53:11 kls Exp $
+ * $Id: recording.c 2.31 2011/06/12 13:04:28 kls Exp $
  */
 
 #include "recording.h"
@@ -1403,11 +1403,12 @@ void cIndexFileGenerator::Action(void)
   bool Rewind = false;
   cFileName FileName(recordingName, false);
   cUnbufferedFile *ReplayFile = FileName.Open();
-  cRingBufferLinear Buffer(IFG_BUFFER_SIZE, MIN_TS_PACKETS_FOR_FRAME_DETECTOR * TS_SIZE);
+  cRingBufferLinear Buffer(IFG_BUFFER_SIZE, TS_SIZE);
   cPatPmtParser PatPmtParser;
   cFrameDetector FrameDetector;
   cIndexFile IndexFile(recordingName, true);
   int BufferChunks = KILOBYTE(1); // no need to read a lot at the beginning when parsing PAT/PMT
+  int FileNumber = 0;
   off_t FileSize = 0;
   off_t FrameOffset = -1;
   Skins.QueueMessage(mtInfo, tr("Regenerating index file"));
@@ -1424,12 +1425,18 @@ void cIndexFileGenerator::Action(void)
         if (Data) {
            if (FrameDetector.Synced()) {
               // Step 3 - generate the index:
-              if (TsPid(Data) == PATPID)
+              if (FrameOffset < 0 && TsPid(Data) == PATPID) {
+                 FileNumber = FileName.Number();
                  FrameOffset = FileSize; // the PAT/PMT is at the beginning of an I-frame
+                 }
               int Processed = FrameDetector.Analyze(Data, Length);
               if (Processed > 0) {
+                 if (FrameDetector.NewPayload() && FrameOffset < 0) {
+                    FileNumber = FileName.Number();
+                    FrameOffset = FileSize;
+                    }
                  if (FrameDetector.NewFrame()) {
-                    IndexFile.Write(FrameDetector.IndependentFrame(), FileName.Number(), FrameOffset >= 0 ? FrameOffset : FileSize);
+                    IndexFile.Write(FrameDetector.IndependentFrame(), FileNumber, FrameOffset);
                     FrameOffset = -1;
                     }
                  FileSize += Processed;

remux.c

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: remux.c 2.55 2011/06/11 11:35:18 kls Exp $
+ * $Id: remux.c 2.56 2011/06/12 13:51:59 kls Exp $
  */
 
 #include "remux.h"
@@ -781,7 +781,8 @@ cFrameDetector::cFrameDetector(int Pid, int Type)
 {
   SetPid(Pid, Type);
   synced = false;
-  newFrame = independentFrame = false;
+  newPayload = newFrame = independentFrame = false;
+  frameTypeOffset = -1;
   numPtsValues = 0;
   numFrames = 0;
   numIFrames = 0;
@@ -808,7 +809,8 @@ void cFrameDetector::SetPid(int Pid, int Type)
 
 void cFrameDetector::Reset(void)
 {
-  newFrame = independentFrame = false;
+  newPayload = newFrame = independentFrame = false;
+  frameTypeOffset = -1;
   payloadUnitOfFrame = 0;
   scanning = false;
   scanner = EMPTY_SCANNER;
@@ -816,9 +818,8 @@ void cFrameDetector::Reset(void)
 
 int cFrameDetector::Analyze(const uchar *Data, int Length)
 {
-  int SeenPayloadStart = false;
   int Processed = 0;
-  newFrame = independentFrame = false;
+  newPayload = newFrame = independentFrame = false;
   while (Length >= TS_SIZE) {
         if (Data[0] != TS_SYNC_BYTE) {
            int Skipped = 1;
@@ -831,11 +832,8 @@ int cFrameDetector::Analyze(const uchar *Data, int Length)
            int Pid = TsPid(Data);
            if (Pid == pid) {
               if (TsPayloadStart(Data)) {
-                 SeenPayloadStart = true;
                  if (synced && Processed)
-                    return Processed;
+                    return Processed; // flush everything before this new payload
-                 if (Length < MIN_TS_PACKETS_FOR_FRAME_DETECTOR * TS_SIZE)
-                    return Processed; // need more data, in case the frame type is not stored in the first TS packet
                  if (framesPerSecond <= 0.0) {
                     // frame rate unknown, so collect a sequence of PTS values:
                     if (numPtsValues < MaxPtsValues && numIFrames < 2) { // collect a sequence containing at least two I-frames
@@ -900,35 +898,41 @@ int cFrameDetector::Analyze(const uchar *Data, int Length)
               if (scanning) {
                  int PayloadOffset = TsPayloadOffset(Data);
                  if (TsPayloadStart(Data)) {
+                    if (synced && Processed)
+                       return Processed; // flush everything before this new payload
+                    newPayload = true;
+                    scanner = EMPTY_SCANNER;
                     PayloadOffset += PesPayloadOffset(Data + PayloadOffset);
                     if (!framesPerPayloadUnit)
                        framesPerPayloadUnit = framesInPayloadUnit;
                     if (DebugFrames && !synced)
                        dbgframes("/");
                     }
-                 int PacketsForFrameDetector = MIN_TS_PACKETS_FOR_FRAME_DETECTOR;
                  for (int i = PayloadOffset; scanning && i < TS_SIZE; i++) {
+                     if (frameTypeOffset < 0) {
                         scanner <<= 8;
                         scanner |= Data[i];
-                     if (i == TS_SIZE - 1) { // it was the last byte in this TS packet
-                        if (SeenPayloadStart && --PacketsForFrameDetector > 0) {
-                           Data += TS_SIZE;
-                           Length -= TS_SIZE;
-                           Processed += TS_SIZE;
-                           if (Length < TS_SIZE)
-                              return Processed;
-                           i = TsPayloadOffset(Data) - 1; // one before the first payload byte of the next TS packet
-                           }
                         }
+                     else
+                        frameTypeOffset += PayloadOffset;
                      switch (type) {
                        case 0x01: // MPEG 1 video
                        case 0x02: // MPEG 2 video
                             if (scanner == 0x00000100) { // Picture Start Code
+                               if (frameTypeOffset < 0) {
+                                  frameTypeOffset = i + 2;
+                                  if (frameTypeOffset >= TS_SIZE) { // the byte to check is in the next TS packet
+                                     frameTypeOffset -= TS_SIZE;
+                                     if (!synced)
+                                        dbgframes("%d>", frameTypeOffset);
+                                     break;
+                                     }
+                                  }
                                scanner = EMPTY_SCANNER;
-                               if (synced && !SeenPayloadStart && Processed)
-                                  return Processed; // flush everything before this new frame
                                newFrame = true;
-                               independentFrame = ((Data[i + 2] >> 3) & 0x07) == 1; // I-Frame
+                               uchar FrameType = (Data[frameTypeOffset] >> 3) & 0x07;
+                               frameTypeOffset = -1;
+                               independentFrame = FrameType == 1; // I-Frame
                                if (synced) {
                                   if (framesPerPayloadUnit <= 1)
                                      scanning = false;
@@ -939,7 +943,7 @@ int cFrameDetector::Analyze(const uchar *Data, int Length)
                                      numIFrames++;
                                   if (numIFrames == 1)
                                      numFrames++;
-                                  dbgframes("%d ", (Data[i + 2] >> 3) & 0x07);
+                                  dbgframes("%u ", FrameType);
                                   }
                                if (synced)
                                   return Processed + TS_SIZE; // flag this new frame
@@ -947,11 +951,20 @@ int cFrameDetector::Analyze(const uchar *Data, int Length)
                             break;
                        case 0x1B: // MPEG 4 video
                             if (scanner == 0x00000109) { // Access Unit Delimiter
+                               if (frameTypeOffset < 0) {
+                                  frameTypeOffset = i + 1;
+                                  if (frameTypeOffset >= TS_SIZE) { // the byte to check is in the next TS packet
+                                     frameTypeOffset -= TS_SIZE;
+                                     if (!synced)
+                                        dbgframes("%d>", frameTypeOffset);
+                                     break;
+                                     }
+                                  }
                                scanner = EMPTY_SCANNER;
-                               if (synced && !SeenPayloadStart && Processed)
-                                  return Processed; // flush everything before this new frame
                                newFrame = true;
-                               independentFrame = Data[i + 1] == 0x10;
+                               uchar FrameType = Data[frameTypeOffset];
+                               frameTypeOffset = -1;
+                               independentFrame = FrameType == 0x10;
                                if (synced) {
                                   if (framesPerPayloadUnit < 0) {
                                      payloadUnitOfFrame = (payloadUnitOfFrame + 1) % -framesPerPayloadUnit;
@@ -969,7 +982,7 @@ int cFrameDetector::Analyze(const uchar *Data, int Length)
                                      numIFrames++;
                                   if (numIFrames == 1)
                                      numFrames++;
-                                  dbgframes("%02X ", Data[i + 1]);
+                                  dbgframes("%02X ", FrameType);
                                   }
                                if (synced)
                                   return Processed + TS_SIZE; // flag this new frame

remux.h

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: remux.h 2.29 2011/05/21 09:53:54 kls Exp $
+ * $Id: remux.h 2.30 2011/06/12 12:49:17 kls Exp $
  */
 
 #ifndef __REMUX_H
@@ -297,7 +297,7 @@ public:
   ~cTsToPes();
   void PutTs(const uchar *Data, int Length);
        ///< Puts the payload data of the single TS packet at Data into the converter.
-       ///< Length is always 188.
+       ///< Length is always TS_SIZE.
        ///< If the given TS packet starts a new PES payload packet, the converter
        ///< will be automatically reset. Any packets before the first one that starts
        ///< a new PES payload packet will be ignored.
@@ -336,16 +336,16 @@ void PesDump(const char *Name, const u_char *Data, int Length);
 
 // Frame detector:
 
-#define MIN_TS_PACKETS_FOR_FRAME_DETECTOR 2
-
 class cFrameDetector {
 private:
   enum { MaxPtsValues = 150 };
   int pid;
   int type;
   bool synced;
+  bool newPayload;
   bool newFrame;
   bool independentFrame;
+  int frameTypeOffset;
   uint32_t ptsValues[MaxPtsValues]; // 32 bit is enough - we only need the delta
   int numPtsValues;
   int numFrames;
@@ -371,12 +371,17 @@ public:
       ///< the frame detector for actual work.
   int Analyze(const uchar *Data, int Length);
       ///< Analyzes the TS packets pointed to by Data. Length is the number of
-      ///< bytes Data points to, and must be a multiple of 188.
+      ///< bytes Data points to, and must be a multiple of TS_SIZE.
       ///< Returns the number of bytes that have been analyzed.
       ///< If the return value is 0, the data was not sufficient for analyzing and
       ///< Analyze() needs to be called again with more actual data.
   bool Synced(void) { return synced; }
       ///< Returns true if the frame detector has synced on the data stream.
+  bool NewPayload(void) { return newPayload; }
+      ///< Returns true if the data given to the last call to Analyze() started a
+      ///< new payload. The caller should remember the current file offset in
+      ///< order to be able to generate an index entry later, when NewFrame()
+      ///< returns true.
   bool NewFrame(void) { return newFrame; }
       ///< Returns true if the data given to the last call to Analyze() started a
       ///< new frame.