- add tstools to evaluate PTS values from TS files for playback

diff --git a/lib/dvb/tstools.cpp b/lib/dvb/tstools.cpp
new file mode 100644 (file)
index 0000000..5d1c7e3
--- /dev/null
+++ b/lib/dvb/tstools.cpp
@@ -0,0 +1,151 @@
+#include <lib/dvb/tstools.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+#include <stdio.h>
+
+eDVBTSTools::eDVBTSTools()
+{
+       m_fd = -1;
+       m_pid = -1;
+       m_maxrange = 1*1024*1024;
+       
+       m_begin_valid = 0;
+       m_end_valid = 0;
+}
+
+eDVBTSTools::~eDVBTSTools()
+{
+       closeFile();
+}
+
+int eDVBTSTools::openFile(const char *filename)
+{
+       closeFile();
+       m_fd = ::open(filename, O_RDONLY);
+       if (m_fd < 0)
+               return -1;
+       return 0;
+}
+
+void eDVBTSTools::closeFile()
+{
+       if (m_fd >= 0)
+               ::close(m_fd);
+}
+
+void eDVBTSTools::setSyncPID(int pid)
+{
+       m_pid = pid;
+}
+
+void eDVBTSTools::setSearchRange(int maxrange)
+{
+       m_maxrange = maxrange;
+}
+
+int eDVBTSTools::getPTS(off_t &offset, pts_t &pts)
+{
+       if (m_fd < 0)
+               return -1;
+       if (m_pid < 0)
+               return -1;
+
+       offset -= offset % 188;
+       
+               // TODO: multiple files!        
+       if (lseek(m_fd, offset, SEEK_SET) < 0)
+               return -1;
+
+       int left = m_maxrange;
+       
+       while (left >= 188)
+       {
+               unsigned char block[188];
+               if (read(m_fd, block, 188) != 188)
+                       break;
+               left -= 188;
+               offset += 188;
+               
+               if (block[0] != 0x47)
+               {
+                       int i = 0;
+                       while (i < 188)
+                               if (block[i] == 0x47)
+                                       break;
+                       offset = lseek(m_fd, i - 188, SEEK_CUR);
+                       continue;
+               }
+               
+               int pid = ((block[1] << 8) | block[2]) & 0x1FFF;
+               int pusi = !!(block[1] & 0x40);
+               
+//             printf("PID %04x, PUSI %d\n", pid, pusi);
+               
+               if (pid != m_pid)
+                       continue;
+               if (!pusi)
+                       continue;
+               
+                       /* ok, now we have a PES header */
+               unsigned char *pes;
+               
+                       /* check for adaption field */
+               if (block[3] & 0x10)
+                       pes = block + block[4] + 4 + 1;
+               else
+                       pes = block + 4;
+               
+                       /* somehow not a startcode. (this is invalid, since pusi was set.) ignore it. */
+               if (pes[0] || pes[1] || (pes[2] != 1))
+                       continue;
+               
+               if (pes[7] & 0x80) /* PTS */
+               {
+                       pts  = ((unsigned long long)(pes[ 9]&0xE))  << 29;
+                       pts |= ((unsigned long long)(pes[10]&0xFF)) << 22;
+                       pts |= ((unsigned long long)(pes[11]&0xFE)) << 14;
+                       pts |= ((unsigned long long)(pes[12]&0xFF)) << 7;
+                       pts |= ((unsigned long long)(pes[13]&0xFE)) >> 1;
+                       offset -= 188;
+                       return 0;
+               }
+       }
+
+       return -1;
+}
+
+void eDVBTSTools::calcBegin()
+{
+       if (m_fd < 0)   
+               return;
+       if (!m_begin_valid)
+       {
+               m_offset_begin = 0;
+               if (!getPTS(m_offset_begin, m_pts_begin))
+                       m_begin_valid = 1;
+       }
+}
+
+void eDVBTSTools::calcEnd()
+{
+       if (m_fd < 0)   
+               return;
+       
+       if (!m_end_valid)
+       {
+               m_offset_end = lseek(m_fd, 0, SEEK_END) - m_maxrange;
+               if (!getPTS(m_offset_end, m_pts_end))
+                       m_end_valid = 1;
+       }
+}
+
+int eDVBTSTools::calcLen(pts_t &len)
+{
+       calcBegin(); calcEnd();
+       if (!(m_begin_valid && m_end_valid))
+               return -1;
+       len = m_pts_end - m_pts_begin;
+       return 0;
+}
+

diff --git a/lib/dvb/tstools.h b/lib/dvb/tstools.h
new file mode 100644 (file)
index 0000000..c6f2cbb
--- /dev/null
+++ b/lib/dvb/tstools.h
@@ -0,0 +1,42 @@
+#ifndef __lib_dvb_tstools_h
+#define __lib_dvb_tstools_h
+
+#include <sys/types.h>
+
+/*
+ * Note: we're interested in PTS values, not STC values.
+ * thus we're not evaluating PES headers, not adaption fields.
+ */
+
+class eDVBTSTools
+{
+public:
+       typedef unsigned long long pts_t;
+       eDVBTSTools();
+       ~eDVBTSTools();
+
+       int openFile(const char *filename);
+       void closeFile();
+       
+       void setSyncPID(int pid);
+       void setSearchRange(int maxrange);
+       
+               /* get first PTS *after* the given offset. */
+       int getPTS(off_t &offset, pts_t &pts);
+       
+       void calcBegin();
+       void calcEnd();
+       
+       int calcLen(pts_t &len);
+       
+private:
+       int m_fd, m_pid;
+       int m_maxrange;
+       
+       int m_begin_valid, m_end_valid;
+       pts_t m_pts_begin, m_pts_end;
+       off_t m_offset_begin, m_offset_end;
+};
+
+
+#endif