/* * Copyright (c) 2010 The WebM project authors. All Rights Reserved. * * Use of this source code is governed by a BSD-style license * that can be found in the LICENSE file in the root of the source * tree. An additional intellectual property rights grant can be found * in the file PATENTS. All contributing project authors may * be found in the AUTHORS file in the root of the source tree. */ /**************************************************************************** * Notes: * * This implementation makes use of 16 bit fixed point verio of two multiply * constants: * 1. sqrt(2) * cos (pi/8) * 2. sqrt(2) * sin (pi/8) * Becuase the first constant is bigger than 1, to maintain the same 16 bit * fixed point precision as the second one, we use a trick of * x * a = x + x*(a-1) * so * x * sqrt(2) * cos (pi/8) = x + x * (sqrt(2) *cos(pi/8)-1). **************************************************************************/ #include "vpx_ports/config.h" #include static const int cospi8sqrt2minus1 = 20091; static const int sinpi8sqrt2 = 35468; static const int rounding = 0; void vp8_short_idct4x4llm_c(short *input, short *output, int pitch) { int i; int a1, b1, c1, d1; short *ip = input; short *op = output; int temp1, temp2; int shortpitch = pitch >> 1; for (i = 0; i < 4; i++) { a1 = ip[0] + ip[8]; b1 = ip[0] - ip[8]; temp1 = (ip[4] * sinpi8sqrt2 + rounding) >> 16; temp2 = ip[12] + ((ip[12] * cospi8sqrt2minus1 + rounding) >> 16); c1 = temp1 - temp2; temp1 = ip[4] + ((ip[4] * cospi8sqrt2minus1 + rounding) >> 16); temp2 = (ip[12] * sinpi8sqrt2 + rounding) >> 16; d1 = temp1 + temp2; op[shortpitch*0] = a1 + d1; op[shortpitch*3] = a1 - d1; op[shortpitch*1] = b1 + c1; op[shortpitch*2] = b1 - c1; ip++; op++; } ip = output; op = output; for (i = 0; i < 4; i++) { a1 = ip[0] + ip[2]; b1 = ip[0] - ip[2]; temp1 = (ip[1] * sinpi8sqrt2 + rounding) >> 16; temp2 = ip[3] + ((ip[3] * cospi8sqrt2minus1 + rounding) >> 16); c1 = temp1 - temp2; temp1 = ip[1] + ((ip[1] * cospi8sqrt2minus1 + rounding) >> 16); temp2 = (ip[3] * sinpi8sqrt2 + rounding) >> 16; d1 = temp1 + temp2; op[0] = (a1 + d1 + 16) >> 5; op[3] = (a1 - d1 + 16) >> 5; op[1] = (b1 + c1 + 16) >> 5; op[2] = (b1 - c1 + 16) >> 5; ip += shortpitch; op += shortpitch; } } void vp8_short_idct4x4llm_1_c(short *input, short *output, int pitch) { int i; int a1; short *op = output; int shortpitch = pitch >> 1; a1 = ((input[0] + 16) >> 5); for (i = 0; i < 4; i++) { op[0] = a1; op[1] = a1; op[2] = a1; op[3] = a1; op += shortpitch; } } void vp8_dc_only_idct_add_c(short input_dc, unsigned char *pred_ptr, unsigned char *dst_ptr, int pitch, int stride) { int a1 = ((input_dc + 16) >> 5); int r, c; for (r = 0; r < 4; r++) { for (c = 0; c < 4; c++) { int a = a1 + pred_ptr[c] ; if (a < 0) a = 0; if (a > 255) a = 255; dst_ptr[c] = (unsigned char) a ; } dst_ptr += stride; pred_ptr += pitch; } } void vp8_short_inv_walsh4x4_c(short *input, short *output) { int i; int a1, b1, c1, d1; int a2, b2, c2, d2; short *ip = input; short *op = output; for (i = 0; i < 4; i++) { a1 = ip[0] + ip[12]; b1 = ip[4] + ip[8]; c1 = ip[4] - ip[8]; d1 = ip[0] - ip[12]; op[0] = a1 + b1; op[4] = c1 + d1; op[8] = a1 - b1; op[12] = d1 - c1; ip++; op++; } ip = output; op = output; for (i = 0; i < 4; i++) { a1 = ip[0] + ip[3]; b1 = ip[1] + ip[2]; c1 = ip[1] - ip[2]; d1 = ip[0] - ip[3]; a2 = a1 + b1; b2 = c1 + d1; c2 = a1 - b1; d2 = d1 - c1; op[0] = (a2 + 1) >> 2; op[1] = (b2 + 1) >> 2; op[2] = (c2 + 1) >> 2; op[3] = (d2 + 1) >> 2; ip += 4; op += 4; } } void vp8_short_inv_walsh4x4_1_c(short *input, short *output) { int i; int a1; short *op = output; a1 = (input[0] + 1 )>> 2; for (i = 0; i < 4; i++) { op[0] = a1; op[1] = a1; op[2] = a1; op[3] = a1; op += 4; } } #if CONFIG_T8X8 #define FAST_IDCT_8X8 void vp8_short_idct8x8_1_c(short *input, short *output, int pitch) { int i, b; int a1; short *op = output; short *orig_op = output; int shortpitch = pitch >> 1; a1 = ((input[0] + 4) >> 3); for (b = 0; b < 4; b++) { for (i = 0; i < 4; i++) { op[0] = a1; op[1] = a1; op[2] = a1; op[3] = a1; op += shortpitch; } op = orig_op + (b+1)%2*4 +(b+1)/2*4*shortpitch; } } void vp8_dc_only_idct_add_8x8_c(short input_dc, unsigned char *pred_ptr, unsigned char *dst_ptr, int pitch, int stride) { int a1 = ((input_dc + 4) >> 3); int r, c, b; unsigned char *orig_pred = pred_ptr; unsigned char *orig_dst = dst_ptr; for (b = 0; b < 4; b++) { for (r = 0; r < 4; r++) { for (c = 0; c < 4; c++) { int a = a1 + pred_ptr[c] ; if (a < 0) a = 0; if (a > 255) a = 255; dst_ptr[c] = (unsigned char) a ; } dst_ptr += stride; pred_ptr += pitch; } dst_ptr = orig_dst + (b+1)%2*4 + (b+1)/2*4*stride; pred_ptr = orig_pred + (b+1)%2*4 + (b+1)/2*4*pitch; } } #ifdef FAST_IDCT_8X8 #define W1 2841 /* 2048*sqrt(2)*cos(1*pi/16) */ #define W2 2676 /* 2048*sqrt(2)*cos(2*pi/16) */ #define W3 2408 /* 2048*sqrt(2)*cos(3*pi/16) */ #define W5 1609 /* 2048*sqrt(2)*cos(5*pi/16) */ #define W6 1108 /* 2048*sqrt(2)*cos(6*pi/16) */ #define W7 565 /* 2048*sqrt(2)*cos(7*pi/16) */ /* row (horizontal) IDCT * * 7 pi 1 dst[k] = sum c[l] * src[l] * cos( -- * * ( k + - ) * l ) l=0 8 2 * * where: c[0] = 128 c[1..7] = 128*sqrt(2) */ static void idctrow (int *blk) { int x0, x1, x2, x3, x4, x5, x6, x7, x8; /* shortcut */ if (!((x1 = blk[4] << 11) | (x2 = blk[6]) | (x3 = blk[2]) | (x4 = blk[1]) | (x5 = blk[7]) | (x6 = blk[5]) | (x7 = blk[3]))) { blk[0] = blk[1] = blk[2] = blk[3] = blk[4] = blk[5] = blk[6] = blk[7] = blk[0] << 3; return; } x0 = (blk[0] << 11) + 128; /* for proper rounding in the fourth stage */ /* first stage */ x8 = W7 * (x4 + x5); x4 = x8 + (W1 - W7) * x4; x5 = x8 - (W1 + W7) * x5; x8 = W3 * (x6 + x7); x6 = x8 - (W3 - W5) * x6; x7 = x8 - (W3 + W5) * x7; /* second stage */ x8 = x0 + x1; x0 -= x1; x1 = W6 * (x3 + x2); x2 = x1 - (W2 + W6) * x2; x3 = x1 + (W2 - W6) * x3; x1 = x4 + x6; x4 -= x6; x6 = x5 + x7; x5 -= x7; /* third stage */ x7 = x8 + x3; x8 -= x3; x3 = x0 + x2; x0 -= x2; x2 = (181 * (x4 + x5) + 128) >> 8; x4 = (181 * (x4 - x5) + 128) >> 8; /* fourth stage */ blk[0] = (x7 + x1) >> 8; blk[1] = (x3 + x2) >> 8; blk[2] = (x0 + x4) >> 8; blk[3] = (x8 + x6) >> 8; blk[4] = (x8 - x6) >> 8; blk[5] = (x0 - x4) >> 8; blk[6] = (x3 - x2) >> 8; blk[7] = (x7 - x1) >> 8; } /* column (vertical) IDCT * * 7 pi 1 dst[8*k] = sum c[l] * src[8*l] * * cos( -- * ( k + - ) * l ) l=0 8 2 * * where: c[0] = 1/1024 c[1..7] = (1/1024)*sqrt(2) */ static void idctcol (int *blk) { int x0, x1, x2, x3, x4, x5, x6, x7, x8; /* shortcut */ if (!((x1 = (blk[8 * 4] << 8)) | (x2 = blk[8 * 6]) | (x3 = blk[8 * 2]) | (x4 = blk[8 * 1]) | (x5 = blk[8 * 7]) | (x6 = blk[8 * 5]) | (x7 = blk[8 * 3]))) { blk[8 * 0] = blk[8 * 1] = blk[8 * 2] = blk[8 * 3] = blk[8 * 4] = blk[8 * 5] = blk[8 * 6] = blk[8 * 7] = ((blk[8 * 0] + 32) >> 6); return; } x0 = (blk[8 * 0] << 8) + 16384; /* first stage */ x8 = W7 * (x4 + x5) + 4; x4 = (x8 + (W1 - W7) * x4) >> 3; x5 = (x8 - (W1 + W7) * x5) >> 3; x8 = W3 * (x6 + x7) + 4; x6 = (x8 - (W3 - W5) * x6) >> 3; x7 = (x8 - (W3 + W5) * x7) >> 3; /* second stage */ x8 = x0 + x1; x0 -= x1; x1 = W6 * (x3 + x2) + 4; x2 = (x1 - (W2 + W6) * x2) >> 3; x3 = (x1 + (W2 - W6) * x3) >> 3; x1 = x4 + x6; x4 -= x6; x6 = x5 + x7; x5 -= x7; /* third stage */ x7 = x8 + x3; x8 -= x3; x3 = x0 + x2; x0 -= x2; x2 = (181 * (x4 + x5) + 128) >> 8; x4 = (181 * (x4 - x5) + 128) >> 8; /* fourth stage */ blk[8 * 0] = (x7 + x1 ) >> 14; blk[8 * 1] = (x3 + x2 ) >> 14; blk[8 * 2] = (x0 + x4 ) >> 14; blk[8 * 3] = (x8 + x6 ) >> 14; blk[8 * 4] = (x8 - x6 ) >> 14; blk[8 * 5] = (x0 - x4 ) >> 14; blk[8 * 6] = (x3 - x2 ) >> 14; blk[8 * 7] = (x7 - x1 ) >> 14; } #define TX_DIM 8 void vp8_short_idct8x8_c(short *coefs, short *block, int pitch) // an approximate 8x8 dct implementation, but not used { int X[TX_DIM*TX_DIM]; int i,j; int shortpitch = pitch >> 1; for (i = 0; i < TX_DIM; i++) { for (j = 0; j < TX_DIM; j++) { X[i * TX_DIM + j] = (int)coefs[i * TX_DIM + j]; } } for (i = 0; i < 8; i++) idctrow (X + 8 * i); for (i = 0; i < 8; i++) idctcol (X + i); for (i = 0; i < TX_DIM; i++) { for (j = 0; j < TX_DIM; j++) { block[i*shortpitch+j] = X[i * TX_DIM + j]>>1; } } } #else /* This is really for testing */ void vp8_short_idct8x8_c(short *input, short *output, int pitch) { int X[8][8]; double C[8][8]={{0.0}}, Ct[8][8]={{0.0}}, temp[8][8]={{0.0}}; int i,j,k; double temp1=0.0; double pi = atan( 1.0 ) * 4.0; //static int count=0; int shortpitch = pitch >> 1; for (i = 0; i < 8; i++) { for (j = 0; j < 8; j++) { X[i][j] = input[i * 8 + j]; } } // TODO: DCT matrix should be calculated once for all for ( j = 0 ; j < 8 ; j++ ) { C[ 0 ][ j ] = 1.0 / sqrt( (double) 8 ); Ct[ j ][ 0 ] = C[ 0 ][ j ]; } for ( i = 1 ; i < 8 ; i++ ) { for ( j = 0 ; j < 8 ; j++ ) { C[ i ][ j ] = sqrt( 2.0 / 8 ) * cos( pi * ( 2 * j + 1 ) * i / ( 2.0 * 8 ) ); Ct[ j ][ i ] = C[ i ][ j ]; } } /* MatrixMultiply( temp, input, C ); */ for ( i = 0 ; i < 8 ; i++ ) { for ( j = 0 ; j < 8 ; j++ ) { temp[ i ][ j ] = 0.0; for ( k = 0 ; k < 8 ; k++ ) temp[ i ][ j ] += X[ i ][ k ] * C[ k ][ j ]; } } /* MatrixMultiply( output, Ct, temp ); */ for ( i = 0 ; i < 8 ; i++ ) { for ( j = 0 ; j < 8 ; j++ ) { temp1 = 0.0; for ( k = 0 ; k < 8 ; k++ ) temp1 += Ct[ i ][ k ] * temp[ k ][ j ]; X[ i ][ j ] = floor( temp1/ 2.0 + 0.5); } } for (i = 0; i < 8; i++) { for (j = 0; j < 8; j++) { output[i*shortpitch+j] = X[i][j]; } } } #endif void vp8_short_ihaar2x2_c(short *input, short *output, int pitch) { int i, x; short *ip = input; //0,1, 4, 8 short *op = output; for (i = 0; i < 16; i++) { op[i] = 0; } op[0] = (ip[0] + ip[1] + ip[4] + ip[8])>>2; op[1] = (ip[0] - ip[1] + ip[4] - ip[8])>>2; op[4] = (ip[0] + ip[1] - ip[4] - ip[8])>>2; op[8] = (ip[0] - ip[1] - ip[4] + ip[8])>>2; } void vp8_short_ihaar2x2_1_c(short *input, short *output, int pitch) { int a1; short *ip = input; short *op = output; a1 = ip[0]>> 2; op[0] = a1; op[2] = a1; op[8] = a1; op[10] = a1; } #endif