[Gnash-commit] gnash ChangeLog libbase/FLVParser.cpp

[Sandro Santilli]

CVSROOT:        /sources/gnash
Module name:    gnash
Changes by:     Sandro Santilli <strk>  07/05/05 15:44:22

Modified files:
        .              : ChangeLog 
        libbase        : FLVParser.cpp 

Log message:
                * libbase/FLVParser.cpp (seekAudio, seekVideo): fixed seeking 
and
                  hopefully made a bit more readable. The computed values are
                  now printed for further debugging. They seem correct to me, 
but
                  it seems they are not correctly used.

CVSWeb URLs:
http://cvs.savannah.gnu.org/viewcvs/gnash/ChangeLog?cvsroot=gnash&r1=1.3105&r2=1.3106
http://cvs.savannah.gnu.org/viewcvs/gnash/libbase/FLVParser.cpp?cvsroot=gnash&r1=1.5&r2=1.6

Patches:
Index: ChangeLog
===================================================================
RCS file: /sources/gnash/gnash/ChangeLog,v
retrieving revision 1.3105
retrieving revision 1.3106
diff -u -b -r1.3105 -r1.3106
--- ChangeLog   5 May 2007 13:31:43 -0000       1.3105
+++ ChangeLog   5 May 2007 15:44:22 -0000       1.3106
@@ -1,5 +1,9 @@
 2007-05-04 Sandro Santilli <address@hidden>
 
+       * libbase/FLVParser.cpp (seekAudio, seekVideo): fixed seeking and
+         hopefully made a bit more readable. The computed values are
+         now printed for further debugging. They seem correct to me, but
+         it seems they are not correctly used.
        * server/asobj/: NetStream.{cpp,h}, NetStreamFfmpeg.{cpp,h},
          NetStreamGst.{cpp,h}: change play() method to take a std::string
          ref instead of a char*; always pass environment when casting args

Index: libbase/FLVParser.cpp
===================================================================
RCS file: /sources/gnash/gnash/libbase/FLVParser.cpp,v
retrieving revision 1.5
retrieving revision 1.6
diff -u -b -r1.5 -r1.6
--- libbase/FLVParser.cpp       18 Apr 2007 14:07:33 -0000      1.5
+++ libbase/FLVParser.cpp       5 May 2007 15:44:22 -0000       1.6
@@ -17,10 +17,11 @@
 // Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 //
 
-// $Id: FLVParser.cpp,v 1.5 2007/04/18 14:07:33 jgilmore Exp $
+// $Id: FLVParser.cpp,v 1.6 2007/05/05 15:44:22 strk Exp $
 
 #include "FLVParser.h"
 #include "amf.h"
+#include "log.h"
 
 FLVParser::FLVParser()
        :
@@ -223,32 +224,34 @@
 
        // If there are no audio greater than the given time
        // the last audioframe is returned
-       if (_audioFrames.back()->timestamp < time) {
+       FLVAudioFrame* lastFrame = _audioFrames.back();
+       if (lastFrame->timestamp < time) {
                _lastAudioFrame = _audioFrames.size() - 2;
-               return _audioFrames.back()->timestamp;
+               return lastFrame->timestamp;
        }
 
        // We try to guess where in the vector the audioframe
        // with the correct timestamp is
-       uint32_t numFrames = _audioFrames.size();
-       uint32_t guess = _audioFrames[numFrames-1]->timestamp / numFrames * 
time;
+       size_t numFrames = _audioFrames.size();
+       double tpf = lastFrame->timestamp / numFrames; // time per frame
+       size_t guess = size_t(time / tpf);
 
        // Here we test if the guess was ok, and adjust if needed.
-       uint32_t bestFrame = guess;
-       uint32_t diff = abs(_audioFrames[bestFrame]->timestamp - time);
-       while (true) {
-               if (bestFrame+1 < numFrames && 
static_cast<uint32_t>(abs(_audioFrames[bestFrame+1]->timestamp - time)) < diff) 
{
-                       bestFrame = bestFrame + 1;
-                       diff = abs(_audioFrames[bestFrame+1]->timestamp - time);
-               } else if (bestFrame-1 > 0 && 
static_cast<uint32_t>(abs(_audioFrames[bestFrame+1]->timestamp - time)) < diff) 
{
-                       bestFrame = bestFrame - 1;
-                       diff = abs(_audioFrames[bestFrame-1]->timestamp - time);
-               } else {
-                       break;
-               }
+       size_t bestFrame = iclamp(guess, 0, _audioFrames.size()-1);
+
+       // Here we test if the guess was ok, and adjust if needed.
+       long diff = _audioFrames[bestFrame]->timestamp - time;
+       if ( diff > 0 ) // our guess was too long
+       {
+               while ( bestFrame > 0 && _audioFrames[bestFrame-1]->timestamp > 
time ) --bestFrame;
+       }
+       else // our guess was too short
+       {
+               while ( bestFrame < _audioFrames.size()-1 && 
_audioFrames[bestFrame+1]->timestamp < time ) ++bestFrame;
        }
 
-       _lastAudioFrame = bestFrame -1;
+       gnash::log_debug("Seek (audio): " SIZET_FMT "/" SIZET_FMT " (%u/%u)", 
bestFrame, numFrames, _audioFrames[bestFrame]->timestamp, time);
+       _lastAudioFrame = bestFrame;
        return _audioFrames[bestFrame]->timestamp;
 
 }
@@ -288,45 +291,72 @@
 
        // We try to guess where in the vector the videoframe
        // with the correct timestamp is
-       uint32_t guess = lastFrame->timestamp / numFrames * time;
+       double tpf = lastFrame->timestamp / numFrames; // time per frame
+       size_t guess = size_t(time / tpf);
+
+       size_t bestFrame = iclamp(guess, 0, _videoFrames.size()-1);
 
        // Here we test if the guess was ok, and adjust if needed.
-       uint32_t bestFrame = guess;
+       long diff = _videoFrames[bestFrame]->timestamp - time;
+       if ( diff > 0 ) // our guess was too long
+       {
+               while ( bestFrame > 0 && _videoFrames[bestFrame-1]->timestamp > 
time ) --bestFrame;
+       }
+       else // our guess was too short
+       {
+               while ( bestFrame < _videoFrames.size()-1 && 
_videoFrames[bestFrame+1]->timestamp < time ) ++bestFrame;
+       }
+
+#if 0
        uint32_t diff = abs(_videoFrames[bestFrame]->timestamp - time);
-       while (true) {
+       while (true)
+       {
                if (bestFrame+1 < numFrames && 
static_cast<uint32_t>(abs(_videoFrames[bestFrame+1]->timestamp - time)) < diff) 
{
-                       bestFrame = bestFrame + 1;
                        diff = abs(_videoFrames[bestFrame+1]->timestamp - time);
-               } else if (bestFrame-1 > 0 && 
static_cast<uint32_t>(abs(_videoFrames[bestFrame+1]->timestamp - time)) < diff) 
{
-                       bestFrame = bestFrame - 1;
+                       bestFrame = bestFrame + 1;
+               } else if (bestFrame > 0 && 
static_cast<uint32_t>(abs(_videoFrames[bestFrame-1]->timestamp - time)) < diff) 
{
                        diff = abs(_videoFrames[bestFrame-1]->timestamp - time);
+                       bestFrame = bestFrame - 1;
                } else {
                        break;
                }
        }
+#endif
 
-       uint32_t rewindKeyframe = bestFrame;
-       uint32_t forwardKeyframe = bestFrame;
 
-       // Rewind to the lastest keyframe
-       while (_videoFrames[rewindKeyframe]->frameType != KEY_FRAME) {
+       // Find closest backward keyframe  
+       size_t rewindKeyframe = bestFrame;
+       while (rewindKeyframe && _videoFrames[rewindKeyframe]->frameType != 
KEY_FRAME) {
                rewindKeyframe--;
        }
 
-       // Forward to the next keyframe
+       // Find closest forward keyframe 
+       uint32_t forwardKeyframe = bestFrame;
        uint32_t size = _videoFrames.size();
-       while (size > forwardKeyframe && 
_videoFrames[forwardKeyframe]->frameType != KEY_FRAME) {
+       while (size > forwardKeyframe+1 && 
_videoFrames[forwardKeyframe]->frameType != KEY_FRAME) {
                forwardKeyframe++;
        }
 
+       // We can't ensure we were able to find a key frame *after* the best 
position
+       // in that case we just use any previous keyframe instead..
+       if ( _videoFrames[forwardKeyframe]->frameType != KEY_FRAME )
+       {
+               bestFrame = rewindKeyframe;
+       }
+       else
+       {
        int32_t forwardDiff = _videoFrames[forwardKeyframe]->timestamp - time;
        int32_t rewindDiff = time - _videoFrames[rewindKeyframe]->timestamp;
 
        if (forwardDiff < rewindDiff) bestFrame = forwardKeyframe;
        else bestFrame = rewindKeyframe;
+       }
+
+       gnash::log_debug("Seek (video): " SIZET_FMT "/" SIZET_FMT " (%u/%u)", 
bestFrame, numFrames, _videoFrames[bestFrame]->timestamp, time);
 
-       _lastVideoFrame = bestFrame - 1;
-       return _videoFrames[bestFrame]->timestamp;
+       _lastVideoFrame = bestFrame;
+       assert(_videoFrames[_lastVideoFrame]->frameType == KEY_FRAME);
+       return _videoFrames[_lastVideoFrame]->timestamp;
 }