ogmreader.cpp

一个播放器 使用了evc 大家可以参考下 哦

			int bufferlen;
			bool isKey;
			result= stream_sampleout(&os[VIDEO_STREAM], sh[VIDEO_STREAM],
										   (bool*)&eos, &isKey,
										   &video_reftime,
										   &temp, &bufferlen);
			if(result==0||(result<0&&(result!=-2052)))
			{
				readpage=1;
			}
			else if (isKey||(!didseek))
			{
				ReleaseMutex(thisvid.hIOMutex);
				memcpy(buffer,temp,bufferlen);
				if (os[VIDEO_STREAM].lastpos>=0) viddata.video_pos=os[VIDEO_STREAM].lastpos;
				else
					viddata.video_pos++;
				return bufferlen;
			}
			else
			{
				if (os[VIDEO_STREAM].lastpos>0) 
					viddata.video_pos=os[VIDEO_STREAM].lastpos;
				else
					viddata.video_pos++;
			}
		}
		else
			readpage=1;
	}
	ReleaseMutex(thisvid.hIOMutex);

	return 0;
}

/*
 * Reads any amount of audio
 * data. FIXME : should return
 * the actual number read.
 */
#define AUDIO_STREAM 1
int AVIDecaps_ReadAudio(char *audbuf, int bytes)
{

	
	static char left[4096];
	int eos=0;
	int stream=AUDIO_STREAM;
	int todo=bytes;
	int got=0;
	//ogg_int16_t* convbuffer=(ogg_int16_t*) audbuf;
	while(!eos)
	{
	    WaitForSingleObject(thisvid.hIOMutex, INFINITE);
		if (readpagea)
		{
			do
			{
				int result=ogg_sync_pageout(&oy,&og);
				readpagea=0;
				if(result==0) /* missing or corrupt data at this page position */
				{
					int readbytes=4096;
					char* buff=ogg_sync_buffer(&oy,4096);
					readbytes=InputMediaRead(buff, 4096);
					if (readbytes==0)
					{
					    ReleaseMutex(thisvid.hIOMutex);
						return 0;
					}
					if (ogg_sync_wrote(&oy,readbytes)==-1)
					{
						int error=1;
					}
					readpagea=1;
					break;
				}
				else if (result<0)
				{
					readpagea=1;
					break;
				}
				stream=ogg_page_serialno(&og);
				ogg_stream_pagein(&os[stream].os,&og); 
			}while(stream!=AUDIO_STREAM);
		}		
		ReleaseMutex(thisvid.hIOMutex);
		if (readpagea) continue;
		int result=1;
		unsigned char* temp;
		int bufferlen;
		bool key;
		if (!sh[1])
		{
			result=ogg_stream_packetout(&os[AUDIO_STREAM].os,&op);
			if(result==0)
			{
				readpagea=1;
				continue; //return NEED_MORE; /* need more data */
			}
			if(result>=0)
			{
				/* we have a packet.  Decode it */
				if(vorbis_synthesis(&vb,&op)==0) /* test for success! */
					vorbis_synthesis_blockin(&vd,&vb);
				/* 

				**pcm is a multichannel float vector.  In stereo, for
				example, pcm[0] is left, and pcm[1] is right.  samples is
				the size of each channel.  Convert the float values
				(-1.<=range<=1.) to whatever PCM format and write it out */
				while((samples=vorbis_synthesis_pcmout(&vd,&pcm))>0)
				{
					int j;
					int i;

					for(i=0;i<vi.channels;i++) 
					{
						ogg_int32_t *src=pcm[i];
						short *dest=((short *)audbuf)+i;
						for(j=0;j<samples;j++) 
						{
							*dest=CLIP_TO_15(src[j]>>9);
							dest+=vi.channels;
						}
					}
					vorbis_synthesis_read(&vd,samples); 
					got+=2*vi.channels*samples;
					audbuf+=2*vi.channels*samples;
					if (got>=2000)
					{
						if (op.granulepos!=-1)
						{
							audio_reftime=mediatime_to_reference_time(SEC_IN_REFTIME, vi.rate, op.granulepos);
							lastpos=op.granulepos;
							if (lastpos==0) lastpos=1;
						}
						else if (lastpos)
						{
							lastpos+=samples;
							audio_reftime=mediatime_to_reference_time(SEC_IN_REFTIME, vi.rate, lastpos);
						}
						return got;
					}

				}	    
			}
			if(result==0)
			{
				readpagea=1;
			}
		}
		else
		{
			while(todo)
			{
				if (leftover)
				{
					if (leftover<=todo)
					{
						memcpy(audbuf,left,leftover);
						audbuf+=leftover;
						todo-=leftover;
						leftover=0;
					}
					else
					{
						memcpy(audbuf,left,todo);
						leftover-=todo;
						memmove(left,left+todo,leftover);
						return bytes;
					}
				}
				result= stream_sampleout(&os[AUDIO_STREAM], sh[AUDIO_STREAM],
										   (bool*)&eos, &key,
										   &audio_reftime, 
										   &temp, &bufferlen);
				if(result==0)
				{
					readpagea=1;
					break;
				}
				else 
				{
					if (bufferlen<todo)
					{
						memcpy(audbuf,temp,bufferlen);
						audbuf+=bufferlen;
						todo-=bufferlen;
					}
					else
					{
						memcpy(left,temp+todo,bufferlen-todo);
						leftover=bufferlen-todo;
						memcpy(audbuf,temp,todo);
						todo=0;
						return bytes;
					}
				}
			}
		}

	}	
  ReleaseMutex(thisvid.hIOMutex);
	
  return 0;
}


double AVIDecaps_FrameRate()
{

	return (double) viddata.fps;
}


int AVIDecaps_AudioSeek(long bytes)
{
   return 0;
}

BOOL AVIDecaps_isKeyframe(long frame)
{
  return true;
}



char onebuff[8192];
int AVIDecaps_Seek(int percent, int isFrame)
{
	__int64 audio_bytes,bytes;
	  WaitForSingleObject(thisvid.hIOMutex, INFINITE);
begin:
	  if (!isFrame)
	  {
			bytes  = (__int64) (((__int64)percent) * fsize)/100;
	  }
	  else
	  {
			double fperc=((double)percent)/((double)viddata.video_frames);
			bytes  = (__int64) (fperc * ((double)fsize));
	  }
	  	InputMediaSeek(bytes,SEEK_SET);
		ogg_sync_clear(&oy);
		stream_state_reset(&os[0]);
		stream_state_reset(&os[1]);
		readpage=readpagea=1;
		lastpos=0;
		if (percent==0)
		{
			video_reftime=0;
			audio_reftime=0;
			ReleaseMutex(thisvid.hIOMutex);
			viddata.video_pos=0;
			didseek=0;	
			oneframelen=0;
			return viddata.audio_bytes;
		}
		video_reftime=-1;
		audio_reftime=-1;
		didseek=1;
		oneframelen=0;
		while(video_reftime<0)
		{
			oneframelen=AVIDecaps_NextVideoFrame(oneframe,0);
			if (oneframelen<0) 
			{
				percent=0;
				goto begin;
			}
		}
		if (gotaudio>0)
		{
			while(audio_reftime<0)
			{
				if (!AVIDecaps_ReadAudio(onebuff,4096))
				{
					percent=0;
					goto begin;
				}			
			}
			while (audio_reftime>	video_reftime)
			{
				oneframelen=AVIDecaps_NextVideoFrame(oneframe,0);
				if (oneframelen<0) 
				{
					percent=0;
					goto begin;
				}
			}
			while (audio_reftime<	video_reftime)
			{
				if (!AVIDecaps_ReadAudio(onebuff,1024))
				{
					percent=0;
					goto begin;
				}			
			}
		}
		didseek=0;	
      ReleaseMutex(thisvid.hIOMutex);
	if (!sh[1])
	{
		audio_bytes=((double)((double)(viddata.video_frames-viddata.video_pos))/viddata.fps)*(double)viddata.a_rate*viddata.a_chans*2;
	}
	else
	{
		audio_bytes=((double)((double)(viddata.video_frames-viddata.video_pos))/viddata.fps)*(double)sh[1]->audio.avgbytespersec;
	}

      return audio_bytes;
}


int AVIDecaps_SeekChapter(int Chapter)
{
	double h,m,s;
	int shouldbeframe;
	char t[4];
	__int64 audio_bytes,bytes;
	double percent;

	  WaitForSingleObject(thisvid.hIOMutex, INFINITE);
begin:
	  int start=0;
#if (_WIN32_WCE >= 300)
	  while (_strnicmp(vcv.user_comments[start],"CHAPTER",7)) start++;
#else
	  while (strncmp(vcv.user_comments[start],"CHAPTER",7)) start++;
#endif
	  strncpy(t,vcv.user_comments[Chapter*2+start]+10,2);
	  t[2]=0;
	  h=atoi(t);
	  strncpy(t,vcv.user_comments[Chapter*2+start]+13,2);
	  t[2]=0;
	  m=atoi(t);
	  strncpy(t,vcv.user_comments[Chapter*2+start]+16,2);
	  t[2]=0;
	  s=atoi(t);
		s=(h*3600)+(m*60)+s;
		percent=(double)(s*viddata.fps)/(double)(viddata.video_frames);
		shouldbeframe=(s*viddata.fps);
repeat:
        bytes  = (__int64) (percent * (double)fsize);
	  	InputMediaSeek(bytes,SEEK_SET);
		ogg_sync_clear(&oy);
		stream_state_reset(&os[0]);
		stream_state_reset(&os[1]);
		readpage=readpagea=1;
		lastpos=0;
		if (percent==0)
		{
			video_reftime=0;
			audio_reftime=0;
			ReleaseMutex(thisvid.hIOMutex);
			viddata.video_pos=0;
			didseek=0;	
			oneframelen=0;
			return viddata.audio_bytes;
		}
		video_reftime=-1;
		audio_reftime=-1;
		didseek=1;
		oneframelen=0;
		do
		{
			oneframelen=AVIDecaps_NextVideoFrame(oneframe,0);
			if (oneframelen<0) 
			{
				percent=0;
				goto begin;
			}
		}while(video_reftime<0||(viddata.video_pos<shouldbeframe));

		if (viddata.video_pos>(shouldbeframe+viddata.fps))
		{
			percent-=.01;
			goto repeat;
		}
		if (gotaudio>0)
		{
			while(audio_reftime<0)
			{
				if (!AVIDecaps_ReadAudio(onebuff,4096))
				{
					percent=0;
					goto begin;
				}			
			}
			while (audio_reftime>	video_reftime)
			{
				oneframelen=AVIDecaps_NextVideoFrame(oneframe,0);
				if (oneframelen<0) 
				{
					percent=0;
					goto begin;
				}
			}
			while (audio_reftime<	video_reftime)
			{
				if (!AVIDecaps_ReadAudio(onebuff,1024))
				{
					percent=0;
					goto begin;
				}			
			}
		}
		didseek=0;	
      ReleaseMutex(thisvid.hIOMutex);
	if (!sh[1])
	{
		audio_bytes=((double)((double)(viddata.video_frames-viddata.video_pos))/viddata.fps)*(double)viddata.a_rate*viddata.a_chans*2;
	}
	else
	{
		audio_bytes=((double)((double)(viddata.video_frames-viddata.video_pos))/viddata.fps)*(double)sh[1]->audio.avgbytespersec;

	}

      return audio_bytes;
}

int AVIDecaps_ReSeekAudio()
{
	__int64 audio_bytes; 
	  WaitForSingleObject(thisvid.hIOMutex, INFINITE);
		while(audio_reftime<0)
		{
			if (!AVIDecaps_ReadAudio(onebuff,4096))
			{
			      ReleaseMutex(thisvid.hIOMutex);
				return 0;
			}
		}
		while (audio_reftime<	video_reftime)
		{
			if (!AVIDecaps_ReadAudio(onebuff,1024))
			{
			      ReleaseMutex(thisvid.hIOMutex);
				return 0;
			}			
		}
      ReleaseMutex(thisvid.hIOMutex);

	if (!sh[1])
	{
		audio_bytes=((double)((double)(viddata.video_frames-viddata.video_pos))/viddata.fps)*(double)viddata.a_rate*viddata.a_chans*2;
	}
	else
	{
		audio_bytes=((double)((double)(viddata.video_frames-viddata.video_pos))/viddata.fps)*(double)sh[1]->audio.avgbytespersec;

	}

    return audio_bytes;
}

double AVIDecaps_GetProgress()
{
	return (double) ((double)(viddata.video_pos))*100.0/((double)viddata.video_frames);
}


int AVIDecaps_Close()
{
	ogg_stream_clear(&os[0].os);
	ogg_stream_clear(&os[1].os);

	/* ogg_page and ogg_packet structs always point to storage in
	   libvorbis.  They're never freed or manipulated directly */

	vorbis_block_clear(&vb);
	vorbis_dsp_clear(&vd);
	vorbis_comment_clear(&vc);
	vorbis_info_clear(&vi);  /* must be called last */

	ogg_sync_clear(&oy);
	if (hDLL)
	{
		InputMediaClose();
		FreeLibrary(hDLL);
		hDLL=NULL;
	}
	return 1;
}

int AVIDecaps_Stop()
{
	if (WaitForSingleObject(thisvid.hIOMutex, 500)==WAIT_TIMEOUT)
		AVIDecaps_Close();
	else
		ReleaseMutex(thisvid.hIOMutex);
	return 1;
	
}


void InitializeReader(reader* rd)
{
	rd->READER_Open=AVIDecaps_Open;
	rd->READER_ReadAudio=AVIDecaps_ReadAudio;
	rd->READER_NextVideoFrame=AVIDecaps_NextVideoFrame;
	rd->READER_Seek=AVIDecaps_Seek;
	rd->READER_ReSeekAudio=AVIDecaps_ReSeekAudio;
	rd->READER_GetProgress=AVIDecaps_GetProgress;
	rd->READER_Close=AVIDecaps_Close;
	rd->READER_isKeyFrame=AVIDecaps_isKeyframe;
	rd->READER_SeekChapter=AVIDecaps_SeekChapter;
	rd->READER_Stop=AVIDecaps_Stop;
}