Function rv34_inv_transform

libavcodec/rv34.c:199–217

* Real Video 3.0/4.0 inverse transform * Code is almost the same as in SVQ3, only scaling is different. */

 * Code is almost the same as in SVQ3, only scaling is different.
 */
static void rv34_inv_transform(DCTELEM *block){
    int temp[16];
    int i;

    rv34_row_transform(temp, block);

    for(i=0; i<4; i++){
        const int z0= 13*(temp[4*0+i] +    temp[4*2+i]) + 0x200;
        const int z1= 13*(temp[4*0+i] -    temp[4*2+i]) + 0x200;
        const int z2=  7* temp[4*1+i] - 17*temp[4*3+i];
        const int z3= 17* temp[4*1+i] +  7*temp[4*3+i];

        block[i*8+0]= (z0 + z3)>>10;
        block[i*8+1]= (z1 + z2)>>10;
        block[i*8+2]= (z1 - z2)>>10;
        block[i*8+3]= (z0 - z3)>>10;
    }

}

/**
 * RealVideo 3.0/4.0 inverse transform for DC block