only sample each 40MB at max, use fallback bitrate if no other bitrate available

[enigma2.git] / lib / dvb / tstools.cpp

diff --git a/lib/dvb/tstools.cpp b/lib/dvb/tstools.cpp
index 5c99ea60c50027d03244d0d6c91b9516bc3d77a3..34edbc9e3289b48be6c5d3218025ba3355cfa453 100644 (file)
--- a/lib/dvb/tstools.cpp
+++ b/lib/dvb/tstools.cpp
@@ -14,6 +14,7 @@ eDVBTSTools::eDVBTSTools()
        m_end_valid = 0;
        
        m_use_streaminfo = 0;
+       m_samples_taken = 0;
 }
 
 eDVBTSTools::~eDVBTSTools()
@@ -34,6 +35,8 @@ int eDVBTSTools::openFile(const char *filename)
                eDebug("no recorded stream information available");
                m_use_streaminfo = 0;
        }
+       
+       m_samples_taken = 0;
 
        if (m_file.open(filename) < 0)
                return -1;
@@ -128,6 +131,8 @@ int eDVBTSTools::getPTS(off_t &offset, pts_t &pts, int fixed)
                        pts |= ((unsigned long long)(pes[13]&0xFE)) >> 1;
                        offset -= 188;
                        
+//                     eDebug("found pts %08llx at %08llx", pts, offset);
+                       
                                /* convert to zero-based */
                        if (fixed)
                                fixupPTS(offset, pts);
@@ -176,11 +181,43 @@ int eDVBTSTools::getOffset(off_t &offset, pts_t &pts)
                return 0;
        } else
        {
-               int bitrate = calcBitrate(); /* in bits/s */
-               if (bitrate <= 0)
-                       return -1;
+//             eDebug("get offset");
+               if (!m_samples_taken)
+                       takeSamples();
+               
+               if (!m_samples.empty())
+               {
+//             eDebug("ok, samples ok");
+                               /* search entry before and after */
+                       std::map<pts_t, off_t>::const_iterator l = m_samples.lower_bound(pts);
+                       std::map<pts_t, off_t>::const_iterator u = l;
+
+                       if (l != m_samples.begin())
+                               --l;
+               
+                       if ((u != m_samples.end()) && (l != m_samples.end()))
+                       {
+                               pts_t pts_diff = u->first - l->first;
+                               off_t offset_diff = u->second - l->second;
+//             eDebug("using: %llx:%llx -> %llx:%llx", l->first, u->first, l->second, u->second);
+       
+                               if (pts_diff)
+                               {
+                                       int bitrate = offset_diff * 90000 * 8 / pts_diff;
+                                       if (bitrate > 0)
+                                       {
+                                               offset = l->second;
+                                               offset += ((pts - l->first) * (pts_t)bitrate) / 8ULL / 90000ULL;
+                                               offset -= offset % 188;
+                                               return 0;
+                                       }
+                               }
+                       }
+               }
                
-               offset = (pts * (pts_t)bitrate) / 8ULL / 90000ULL;
+               eDebug("falling back");
+               int bitrate = calcBitrate();
+               offset = pts * (pts_t)bitrate / 8ULL / 90000ULL;
                offset -= offset % 188;
 
                return 0;
@@ -275,4 +312,35 @@ int eDVBTSTools::calcBitrate()
                return -1;
        
        return bitrate;
+}
+
+       /* pts, off */
+void eDVBTSTools::takeSamples()
+{
+       m_samples_taken = 1;
+       m_samples.clear();
+       pts_t dummy;
+       if (calcLen(dummy) == -1)
+               return;
+       
+       int nr_samples = 30;
+       off_t bytes_per_sample = (m_offset_end - m_offset_begin) / (long long)nr_samples;
+       if (bytes_per_sample < 40*1024*1024)
+               bytes_per_sample = 40*1024*1024;
+       
+       bytes_per_sample -= bytes_per_sample % 188;
+       
+       for (off_t offset = m_offset_begin; offset < m_offset_end; offset += bytes_per_sample)
+       {
+               off_t o = offset;
+               pts_t p;
+               if (!eDVBTSTools::getPTS(o, p, 1))
+               {
+//                     eDebug("sample: %llx, %llx", o, p);
+                       m_samples[p] = o;
+               }
+       }
+       m_samples[m_pts_begin] = m_offset_begin;
+       m_samples[m_pts_end] = m_offset_end;
+//     eDebug("begin, end: %llx %llx", m_offset_begin, m_offset_end); 
 }