?? block.c
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/*
***********************************************************************
* COPYRIGHT AND WARRANTY INFORMATION
*
* Copyright 2001, International Telecommunications Union, Geneva
*
* DISCLAIMER OF WARRANTY
*
* These software programs are available to the user without any
* license fee or royalty on an "as is" basis. The ITU disclaims
* any and all warranties, whether express, implied, or
* statutory, including any implied warranties of merchantability
* or of fitness for a particular purpose. In no event shall the
* contributor or the ITU be liable for any incidental, punitive, or
* consequential damages of any kind whatsoever arising from the
* use of these programs.
*
* This disclaimer of warranty extends to the user of these programs
* and user's customers, employees, agents, transferees, successors,
* and assigns.
*
* The ITU does not represent or warrant that the programs furnished
* hereunder are free of infringement of any third-party patents.
* Commercial implementations of ITU-T Recommendations, including
* shareware, may be subject to royalty fees to patent holders.
* Information regarding the ITU-T patent policy is available from
* the ITU Web site at http://www.itu.int.
*
* THIS IS NOT A GRANT OF PATENT RIGHTS - SEE THE ITU-T PATENT POLICY.
************************************************************************
*/
/*!
***********************************************************************
* \file
* block.c
*
* \brief
* Block functions
*
* \author
* Main contributors (see contributors.h for copyright, address and affiliation details)
* - Inge Lille-Lang鴜 <inge.lille-langoy@telenor.com>
* - Rickard Sjoberg <rickard.sjoberg@era.ericsson.se>
***********************************************************************
*/
#include "contributors.h"
#include <stdlib.h>
#include <math.h>
#include "block.h"
/*!
***********************************************************************
* \brief
* makes and returns 4x4 blocks with all 5 intra prediction modes
*
* \return
* DECODING_OK decoding of intraprediction mode was sucessfull \n
* SEARCH_SYNC search next sync element as errors while decoding occured
***********************************************************************
*/
int intrapred(struct img_par *img, //!< image parameters
int ioff, //!< ??
int joff, //!< ??
int img_block_x, //!< ??
int img_block_y) //!< ??
{
int js0=0,js1,js2,i,j;
int img_y=0,img_x=0;
int ia[7];
byte predmode = img->ipredmode[img_block_x+1][img_block_y+1];
int block_available_up = (img->ipredmode[img_block_x+1][img_block_y] >=0);
int block_available_left = (img->ipredmode[img_block_x][img_block_y+1] >=0);
img_x=img_block_x*4;
img_y=img_block_y*4;
for (i=0; i<7; i++)
ia[i]=0;
switch (predmode)
{
case DC_PRED: // DC prediction
js1=0;
js2=0;
for (i=0;i<BLOCK_SIZE;i++)
{
if (block_available_up)
js1=js1+imgY[img_y-1][img_x+i];
if (block_available_left)
js2=js2+imgY[img_y+i][img_x-1];
}
if(block_available_left && block_available_up)
js0=(js1+js2+4)/8; // make DC prediction from both block above and to the left
if(block_available_left && !block_available_up)
js0=(js2+2)/4; // make DC prediction from block to the left
if(!block_available_left && block_available_up)
js0=(js1+2)/4; // make DC prediction from block above
if(!block_available_left && !block_available_up)
js0=128; // current block is the upper left
// no block to make DC pred.from
for(i=0;i<BLOCK_SIZE;i++)
for(j=0;j<BLOCK_SIZE;j++)
img->mpr[i+ioff][j+joff]=js0; // store predicted 4x4 block
break;
case VERT_PRED: // vertical prediction from block above
for(j=0;j<BLOCK_SIZE;j++)
for(i=0;i<BLOCK_SIZE;i++)
img->mpr[i+ioff][j+joff]=imgY[img_y-1][img_x+i];// store predicted 4x4 block
break;
case HOR_PRED: // horisontal prediction from left block
for(j=0;j<BLOCK_SIZE;j++)
for(i=0;i<BLOCK_SIZE;i++)
img->mpr[i+ioff][j+joff]=imgY[img_y+j][img_x-1]; // store predicted 4x4 block
break;
case DIAG_PRED_LR_45: // diagonal prediction from left to right 45 degree
ia[0]=(imgY[img_y+3][img_x-1]+2*imgY[img_y+2][img_x-1]+imgY[img_y+1][img_x-1]+2)/4;
ia[1]=(imgY[img_y+2][img_x-1]+2*imgY[img_y+1][img_x-1]+imgY[img_y+0][img_x-1]+2)/4;
ia[2]=(imgY[img_y+1][img_x-1]+2*imgY[img_y+0][img_x-1]+imgY[img_y-1][img_x-1]+2)/4;
ia[3]=(imgY[img_y+0][img_x-1]+2*imgY[img_y-1][img_x-1]+imgY[img_y-1][img_x+0]+2)/4;
ia[4]=(imgY[img_y-1][img_x-1]+2*imgY[img_y-1][img_x+0]+imgY[img_y-1][img_x+1]+2)/4;
ia[5]=(imgY[img_y-1][img_x+0]+2*imgY[img_y-1][img_x+1]+imgY[img_y-1][img_x+2]+2)/4;
ia[6]=(imgY[img_y-1][img_x+1]+2*imgY[img_y-1][img_x+2]+imgY[img_y-1][img_x+3]+2)/4;
for(i=0;i<BLOCK_SIZE;i++)
for(j=0;j<BLOCK_SIZE;j++)
img->mpr[i+ioff][j+joff]=ia[i-j+3];
break;
case DIAG_PRED_RL: // diagonal prediction 22.5 deg to vertical plane
ia[0]=(imgY[img_y-1][img_x+0]+imgY[img_y-1][img_x+1])/2;
ia[1]= imgY[img_y-1][img_x+1];
ia[2]=(imgY[img_y-1][img_x+1]+imgY[img_y-1][img_x+2])/2;
ia[3]= imgY[img_y-1][img_x+2];
ia[4]=(imgY[img_y-1][img_x+2]+imgY[img_y-1][img_x+3])/2;
ia[5]= imgY[img_y-1][img_x+3];
for(i=0;i<BLOCK_SIZE;i++)
for(j=0;j<BLOCK_SIZE;j++)
img->mpr[i+ioff][j+joff]=ia[MAP[j][i]];
break;
case DIAG_PRED_LR:// diagonal prediction -22.5 deg to horizontal plane
ia[0]=(imgY[img_y+0][img_x-1]+imgY[img_y+1][img_x-1])/2;
ia[1]= imgY[img_y+1][img_x-1];
ia[2]=(imgY[img_y+1][img_x-1]+imgY[img_y+2][img_x-1])/2;
ia[3]= imgY[img_y+2][img_x-1];
ia[4]=(imgY[img_y+2][img_x-1]+imgY[img_y+3][img_x-1])/2;
ia[5]= imgY[img_y+3][img_x-1];
for(i=0;i<BLOCK_SIZE;i++)
for(j=0;j<BLOCK_SIZE;j++)
img->mpr[i+ioff][j+joff]=ia[MAP[i][j]];
break;
default:
printf("Error: illegal prediction mode input: %d\n",predmode);
return SEARCH_SYNC;
break;
}
return DECODING_OK;
}
/*!
***********************************************************************
* \return
* best SAD
***********************************************************************
*/
int intrapred_luma_2(struct img_par *img, //!< image parameters
int predmode) //!< prediction mode
{
int s0=0,s1,s2;
int i,j;
int ih,iv;
int ib,ic,iaa;
int mb_nr = img->current_mb_nr;
int mb_width = img->width/16;
int mb_available_up = (img->mb_y == 0) ? 0 : (img->mb_data[mb_nr].slice_nr == img->mb_data[mb_nr-mb_width].slice_nr);
int mb_available_left = (img->mb_x == 0) ? 0 : (img->mb_data[mb_nr].slice_nr == img->mb_data[mb_nr-1].slice_nr);
if(img->UseConstrainedIntraPred)
{
// If neighbor MB is Inter, flag as not available
if (mb_available_up && (img->intra_mb[mb_nr-mb_width] ==0))
mb_available_up = 0;
if (mb_available_left && (img->intra_mb[mb_nr-1] ==0))
mb_available_left = 0;
}
s1=s2=0;
switch (predmode)
{
case VERT_PRED_16: // vertical prediction from block above
for(j=0;j<MB_BLOCK_SIZE;j++)
for(i=0;i<MB_BLOCK_SIZE;i++)
img->mpr[i][j]=imgY[img->pix_y-1][img->pix_x+i];// store predicted 16x16 block
break;
case HOR_PRED_16: // horisontal prediction from left block
for(j=0;j<MB_BLOCK_SIZE;j++)
for(i=0;i<MB_BLOCK_SIZE;i++)
img->mpr[i][j]=imgY[img->pix_y+j][img->pix_x-1]; // store predicted 16x16 block
break;
case DC_PRED_16: // DC prediction
s1=s2=0;
for (i=0; i < MB_BLOCK_SIZE; i++)
{
if (mb_available_up)
s1 += imgY[img->pix_y-1][img->pix_x+i]; // sum hor pix
if (mb_available_left)
s2 += imgY[img->pix_y+i][img->pix_x-1]; // sum vert pix
}
if (mb_available_up && mb_available_left)
s0=(s1+s2+16)/(2*MB_BLOCK_SIZE); // no edge
if (!mb_available_up && mb_available_left)
s0=(s2+8)/MB_BLOCK_SIZE; // upper edge
if (mb_available_up && !mb_available_left)
s0=(s1+8)/MB_BLOCK_SIZE; // left edge
if (!mb_available_up && !mb_available_left)
s0=128; // top left corner, nothing to predict from
for(i=0;i<MB_BLOCK_SIZE;i++)
for(j=0;j<MB_BLOCK_SIZE;j++)
{
img->mpr[i][j]=s0;
}
break;
case PLANE_16:// 16 bit integer plan pred
ih=0;
iv=0;
for (i=1;i<9;i++)
{
ih += i*(imgY[img->pix_y-1][img->pix_x+7+i] - imgY[img->pix_y-1][img->pix_x+7-i]);
iv += i*(imgY[img->pix_y+7+i][img->pix_x-1] - imgY[img->pix_y+7-i][img->pix_x-1]);
}
ib=5*(ih/4)/16;
ic=5*(iv/4)/16;
iaa=16*(imgY[img->pix_y-1][img->pix_x+15]+imgY[img->pix_y+15][img->pix_x-1]);
for (j=0;j< MB_BLOCK_SIZE;j++)
{
for (i=0;i< MB_BLOCK_SIZE;i++)
{
img->mpr[i][j]=max(0,min((iaa+(i-7)*ib +(j-7)*ic + 16)/32,255));
}
}// store plane prediction
break;
default:
{ // indication of fault in bitstream,exit
printf("Error: illegal prediction mode input: %d\n",predmode);
return SEARCH_SYNC;
}
}
return DECODING_OK;
}
/*!
***********************************************************************
* \brief
* Inverse 4x4 transformation, transforms cof to m7
***********************************************************************
*/
void itrans(struct img_par *img, //!< image parameters
int ioff, //!< index to 4x4 block
int joff, //!<
int i0, //!<
int j0) //!<
{
int i,j,i1,j1;
int m5[4];
int m6[4];
// horizontal
for (j=0;j<BLOCK_SIZE;j++)
{
for (i=0;i<BLOCK_SIZE;i++)
{
m5[i]=img->cof[i0][j0][i][j];
}
m6[0]=(m5[0]+m5[2])*13;
m6[1]=(m5[0]-m5[2])*13;
m6[2]=m5[1]*7-m5[3]*17;
m6[3]=m5[1]*17+m5[3]*7;
for (i=0;i<2;i++)
{
i1=3-i;
img->m7[i][j]=m6[i]+m6[i1];
img->m7[i1][j]=m6[i]-m6[i1];
}
}
// vertical
for (i=0;i<BLOCK_SIZE;i++)
{
for (j=0;j<BLOCK_SIZE;j++)
m5[j]=img->m7[i][j];
m6[0]=(m5[0]+m5[2])*13;
m6[1]=(m5[0]-m5[2])*13;
m6[2]=m5[1]*7-m5[3]*17;
m6[3]=m5[1]*17+m5[3]*7;
for (j=0;j<2;j++)
{
j1=3-j;
img->m7[i][j]=mmax(0,mmin(255,(m6[j]+m6[j1]+img->mpr[i+ioff][j+joff]*JQQ+JQQ2)/JQQ));
img->m7[i][j1]=mmax(0,mmin(255,(m6[j]-m6[j1]+img->mpr[i+ioff][j1+joff]*JQQ+JQQ2)/JQQ));
}
}
}
/*!
***********************************************************************
* \brief
* invers transform
***********************************************************************
*/
void itrans_2(
struct img_par *img) //!< image parameters
{
int i,j,i1,j1;
int M5[4];
int M6[4];
// horizontal
for (j=0;j<4;j++)
{
for (i=0;i<4;i++)
M5[i]=img->cof[i][j][0][0];
M6[0]=(M5[0]+M5[2])*13;
M6[1]=(M5[0]-M5[2])*13;
M6[2]= M5[1]*7 -M5[3]*17;
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