disable backtrack to prev sequence start code

[vuplus_dvbapp] / lib / dvb / tstools.cpp

diff --git a/lib/dvb/tstools.cpp b/lib/dvb/tstools.cpp
index 6d64463..438f6d6 100644 (file)
--- a/lib/dvb/tstools.cpp
+++ b/lib/dvb/tstools.cpp
@@ -7,6 +7,7 @@
 #include <stdio.h>
 
 eDVBTSTools::eDVBTSTools()
+       :m_file_lock(true)
 {
        m_pid = -1;
        m_maxrange = 256*1024;
@@ -47,6 +48,7 @@ int eDVBTSTools::openFile(const char *filename, int nostreaminfo)
        
        m_samples_taken = 0;
 
+       eSingleLocker l(m_file_lock);
        if (m_file.open(filename, 1) < 0)
                return -1;
        return 0;
@@ -54,6 +56,7 @@ int eDVBTSTools::openFile(const char *filename, int nostreaminfo)
 
 void eDVBTSTools::closeFile()
 {
+       eSingleLocker l(m_file_lock);
        m_file.close();
 }
 
@@ -78,7 +81,8 @@ int eDVBTSTools::getPTS(off_t &offset, pts_t &pts, int fixed)
                return -1;
 
        offset -= offset % 188;
-       
+
+       eSingleLocker l(m_file_lock);
        if (m_file.lseek(offset, SEEK_SET) < 0)
        {
                eDebug("lseek failed");
@@ -417,7 +421,8 @@ void eDVBTSTools::calcEnd()
 {
        if (!m_file.valid())
                return;
-       
+
+       eSingleLocker l(m_file_lock);
        off_t end = m_file.lseek(0, SEEK_END);
        
        if (llabs(end - m_last_filelength) > 1*1024*1024)
@@ -574,6 +579,7 @@ int eDVBTSTools::findPMT(int &pmt_pid, int &service_id)
                return -1;
        }
 
+       eSingleLocker l(m_file_lock);
        if (m_file.lseek(0, SEEK_SET) < 0)
        {
                eDebug("seek failed");
@@ -692,9 +698,26 @@ int eDVBTSTools::findFrame(off_t &_offset, size_t &len, int &direction, int fram
                else if (direction == +1)
                        direction = 0;
        }
-                       /* let's find the next frame after the given offset */
        off_t start = offset;
 
+#if 0
+                       /* backtrack to find the previous sequence start, in case of MPEG2 */
+       if ((data & 0xFF) == 0x00) {
+               do {
+                       --start;
+                       if (m_streaminfo.getStructureEntry(start, data, 0))
+                       {
+                               eDebug("get previous failed");
+                               return -1;
+                       }
+               } while (((data & 0xFF) != 9) && ((data & 0xFF) != 0x00) && ((data & 0xFF) != 0xB3)); /* sequence start or previous frame */
+               if ((data & 0xFF) != 0xB3)
+                       start = offset;  /* Failed to find corresponding sequence start, so never mind */
+       }
+
+#endif
+
+                       /* let's find the next frame after the given offset */
        do {
                if (m_streaminfo.getStructureEntry(offset, data, 1))
                {
@@ -709,9 +732,11 @@ int eDVBTSTools::findFrame(off_t &_offset, size_t &len, int &direction, int fram
 //             eDebug("%08llx@%llx (next)", data, offset);
        } while (((data & 0xFF) != 9) && ((data & 0xFF) != 0x00)); /* next frame */
 
+#if 0
                        /* align to TS pkt start */
-//     start = start - (start % 188);
-//     offset = offset - (offset % 188);
+       start = start - (start % 188);
+       offset = offset - (offset % 188);
+#endif
 
        len = offset - start;
        _offset = start;
@@ -722,18 +747,23 @@ int eDVBTSTools::findFrame(off_t &_offset, size_t &len, int &direction, int fram
 
 int eDVBTSTools::findNextPicture(off_t &offset, size_t &len, int &distance, int frame_types)
 {
-       int nr_frames = 0;
+       int nr_frames, direction;
 //     eDebug("trying to move %d frames at %llx", distance, offset);
        
        frame_types = frametypeI; /* TODO: intelligent "allow IP frames when not crossing an I-Frame */
 
-       int direction = distance > 0 ? 0 : -1;
-       distance = abs(distance);
-       
        off_t new_offset = offset;
        size_t new_len = len;
        int first = 1;
 
+       if (distance > 0) {
+               direction = 0;
+                nr_frames = 0;
+        } else {
+               direction = -1;
+                nr_frames = -1;
+               distance = -distance+1;
+        }      
        while (distance > 0)
        {
                int dir = direction;
@@ -747,12 +777,18 @@ int eDVBTSTools::findNextPicture(off_t &offset, size_t &len, int &distance, int
                
 //             eDebug("we moved %d, %d to go frames (now at %llx)", dir, distance, new_offset);
 
-               if (distance >= 0 || first)
+               if (distance >= 0 || direction == 0)
                {
                        first = 0;
                        offset = new_offset;
                        len = new_len;
                        nr_frames += abs(dir);
+               } 
+               else if (first) {
+                       first = 0;
+                       offset = new_offset;
+                       len = new_len;
+                       nr_frames += abs(dir) + distance; // never jump forward during rewind
                }
        }