Theora Video/Audio Sync Fix

by Jackie Hayes · in Torque Game Engine · 11/05/2005 (3:41 pm) · 17 replies · personal note....

void resetVars();
[b]//***JH
void TheoraTexture::MagicalTrevor::resetVars()
{
   mBufListHead = NULL;
   mLastBufferID = -1;
}
//***JH[/b]
void TheoraTexture::stop()
{

   mPlaying = false;
   if(mPlayThread)
   {
      delete mPlayThread;
      if(mHasVorbis)
		{
			alxStop(mVorbisHandle);
		}
      mPlayThread = NULL;
	  mVorbisHandle = NULL;
	  mVorbisBuffer = NULL;

	  [b]mMagicalTrevor.resetVars();    //<<***JH[/b]
   }

}

************************

bool TheoraTexture::playLoop()
{
   bool fMoreVideo = true;
   bool fMoreAudio = mHasVorbis;

   // timing variables
   F64 dVBuffTime = 0;
   F64 dLastFrame = 0;

   mPlaying = true;
   mCurrentTime = 0.f;
   mStartTick = Platform::getRealMilliseconds();

   bool isAudioActive = false;

   while(mPlaying)
   {
      if(fMoreAudio)
         fMoreAudio = readyAudio();

      if(fMoreVideo)
         fMoreVideo = readyVideo(dLastFrame, dVBuffTime);

      if(!fMoreVideo && !fMoreAudio)
	  {
		  break;   // if we have no more audio to buffer, and no more video frames to display, we are done
	  }

      // if we haven't started yet, start it! :)
      if(!isAudioActive && mHasVorbis)
      {
         alxPlay(mVorbisHandle);
         isAudioActive = true;
      }

      // if we're set for the next frame, sleep
      /*S32 t = (int)((double) 1000 * (dVBuffTime - getTheoraTime()));
      if(t>0)
         Platform::sleep(t); */
      U32 safety = 0;
      while((dVBuffTime - getTheoraTime()) >= 0.f && safety < 500)
      {
         safety++;
         Platform::sleep(2);
      }

      // time to draw the frame!
      drawFrame();

      // keep track of the last frame time
      dLastFrame = getTheoraTime();
   }

   mPlaying = false;
   mVorbisHandle = NULL;
   mVorbisBuffer = NULL;

   [b]mMagicalTrevor.resetVars();    //<<***JH[/b]

   return false;
}
FreeListChunker<BufInf> mBuffPool;
      BufInf *mBufListHead;
//      ALint mLastBufferID;
[b]      ALuint mLastBufferID; // MPD - Buffer ID's should be unsigned.  Having it signed can cause issues
      bool   mLastBufferIDValid; // MPD - Cannot determine by value if mLastBufferID is valid so need to track seperately
[/b]
      void *mMutex;
TheoraTexture::MagicalTrevor::MagicalTrevor()
{
   mBufListHead = NULL;
//   mLastBufferID = -1;
[b]   mLastBufferIDValid = false; // MPD - Cannot use a 'magic' number for mLastBufferID so track seperately
[/b]
   mMutex = Mutex::createMutex();
}

const F64 TheoraTexture::MagicalTrevor::advanceTime(const ALuint buffId)
{
   MutexHandle handle;
   handle.lock(mMutex);

   // We basically find the last entry on the list that references
   // this buffId, then count how much time it + all its followers
   // contains, and return that amount. Then the list is truncated.

   // Skip if we just saw this one... we'd better not go
   // through all the buffers in one advanceTime call, that would
   // confuse the hell out of this code.
//   if(mLastBufferID == buffId)
[b]   if (mLastBufferIDValid && mLastBufferID == buffId) // MPD [/b]
      return 0.f;

   mLastBufferID = buffId; [b]mLastBufferIDValid = true; // MPD[/b]

   // Ok, find last occurence of buffId.
   BufInf **walk = &mBufListHead;

....

void TheoraTexture::MagicalTrevor::reset()
{
   MutexHandle handle;
   handle.lock(mMutex);

   // Since we're mostly touched by the thread, let's make this a mutex
   // operation.

   mBuffPool.freeBlocks();
   mBufListHead = NULL;
//   mLastBufferID = -1;
[b]   mLastBufferIDValid = false; // MPD - Cannot use a 'magic' number for mLastBufferID so track seperately[/b]
}

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Theora Video/Audio Sync Fix

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