rc_data.c

用MPEG-4对YUV视频文件编码压缩成divx视频文件

/* ****************************************************************************
* ***********************    INCLUDE FILES    ******************************* */

#include <stdio.h>
#include <stdlib.h>

#include "rc_data.h"

/*!
 ************************************************************************   
 * \brief
 *    init queque write and read pointer
 *    queue is used to save previous frame quant and complexity
 ************************************************************************
 */
void rch_init(RCQ2_SAVE_QUEUE* pqueue)
{	
	int i;
	for(i=0;i<2;i++){
		pqueue[i].read=0; /*读写指针初始置为0 modify by lxq*/
		pqueue[i].write=0;
	}

}
/*!
 ************************************************************************   
 * \brief
 *    get total queue size 
 *
 ************************************************************************
 */
int rch_get_size(RCQ2_SAVE_QUEUE* pqueue,int frametype)
{
	return (pqueue[frametype].write-pqueue[frametype].read+MAX_SLIDING_WINDOW)%MAX_SLIDING_WINDOW;
}
/*!
 ************************************************************************   
 * \brief
 *    get usable queue data to compute quadratic rate distortion model param
 *
 ************************************************************************
 */
void rch_get_data(RCQ2_SAVE_QUEUE* pqueue,int frametype,int w,int* Qp,double* Rp)
{	
	int temp_read,i;
	int n=rch_get_size(pqueue,frametype);
	temp_read=pqueue[frametype].read;
	for(i=n; i>n-w; i--){
		if(pqueue[frametype].read!=pqueue[frametype].write)
		{
			Qp[n-i]=pqueue[frametype].Qall[pqueue[frametype].read];
 			Rp[n-i]=pqueue[frametype].Rall[pqueue[frametype].read];
			pqueue[frametype].read=(pqueue[frametype].read+1)%MAX_SLIDING_WINDOW;
		}
		else
			i=n-w;
	}
	pqueue[frametype].read=temp_read;
}
/*!
 ************************************************************************   
 * \brief
 *    queue is used to save current frame quant and complexity for later use
 *
 ************************************************************************
 */
void rch_store_after(RCQ2_SAVE_QUEUE* pqueue,int frametype,int Rc,int Qc,int Hc,int Ec)
{	
	if(((pqueue[frametype].write+1)%MAX_SLIDING_WINDOW)==pqueue[frametype].read)
		pqueue[frametype].read=(pqueue[frametype].read+1)%MAX_SLIDING_WINDOW;
	
	pqueue[frametype].Rall[pqueue[frametype].write] = (double)(Rc-Hc)/(double)Ec;
	pqueue[frametype].Qall[pqueue[frametype].write]= Qc;
	pqueue[frametype].write=(pqueue[frametype].write+1)%MAX_SLIDING_WINDOW;

}