1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205
|
/* -*- C++ -*-
*
* resize_image.cpp - resize image using smoothing and resampling
*
* Copyright (c) 2001-2012 Ogapee. All rights reserved.
*
* ogapee@aqua.dti2.ne.jp
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <stdio.h>
#include <string.h>
static unsigned long *pixel_accum=NULL;
static unsigned long *pixel_accum_num=NULL;
static int pixel_accum_size=0;
static unsigned long tmp_acc[4];
static unsigned long tmp_acc_num[4];
static void calcWeightedSumColumnInit(unsigned char **src,
int interpolation_height,
int image_width, int image_height, int image_pixel_width, int byte_per_pixel)
{
int y_end = -interpolation_height/2+interpolation_height;
memset(pixel_accum, 0, image_width*byte_per_pixel*sizeof(unsigned long));
memset(pixel_accum_num, 0, image_width*byte_per_pixel*sizeof(unsigned long));
for (int s=0 ; s<byte_per_pixel ; s++){
for (int i=0 ; i<y_end-1 ; i++){
if (i >= image_height) break;
unsigned long *pa = pixel_accum + image_width*s;
unsigned long *pan = pixel_accum_num + image_width*s;
unsigned char *p = *src+image_pixel_width*i+s;
for (int j=image_width ; j!=0 ; j--, p+=byte_per_pixel){
*pa++ += *p;
(*pan++)++;
}
}
}
}
static void calcWeightedSumColumn(unsigned char **src, int y,
int interpolation_height,
int image_width, int image_height, int image_pixel_width, int byte_per_pixel)
{
int y_start = y-interpolation_height/2;
int y_end = y-interpolation_height/2+interpolation_height;
for (int s=0 ; s<byte_per_pixel ; s++){
if ((y_start-1)>=0 && (y_start-1)<image_height){
unsigned long *pa = pixel_accum + image_width*s;
unsigned long *pan = pixel_accum_num + image_width*s;
unsigned char *p = *src+image_pixel_width*(y_start-1)+s;
for (int j=image_width ; j!=0 ; j--, p+=byte_per_pixel){
*pa++ -= *p;
(*pan++)--;
}
}
if ((y_end-1)>=0 && (y_end-1)<image_height){
unsigned long *pa = pixel_accum + image_width*s;
unsigned long *pan = pixel_accum_num + image_width*s;
unsigned char *p = *src+image_pixel_width*(y_end-1)+s;
for (int j=image_width ; j!=0 ; j--, p+=byte_per_pixel){
*pa++ += *p;
(*pan++)++;
}
}
}
}
static void calcWeightedSum(unsigned char **dst, unsigned char **src, int x,
int interpolation_width,
int image_width, int byte_per_pixel)
{
int x_start = x-interpolation_width/2;
int x_end = x-interpolation_width/2+interpolation_width;
for (int s=0 ; s<byte_per_pixel ; s++){
if ((x_start-1)>=0 && (x_start-1)<image_width){
tmp_acc[s] -= pixel_accum[image_width*s+x_start-1];
tmp_acc_num[s] -= pixel_accum_num[image_width*s+x_start-1];
}
if ((x_end-1)>=0 && (x_end-1)<image_width){
tmp_acc[s] += pixel_accum[image_width*s+x_end-1];
tmp_acc_num[s] += pixel_accum_num[image_width*s+x_end-1];
}
*(*dst)++ = (unsigned char)(tmp_acc[s]/tmp_acc_num[s]);
}
}
void resizeImage( unsigned char *dst_buffer, int dst_width, int dst_height, int dst_total_width,
unsigned char *src_buffer, int src_width, int src_height, int src_total_width,
int byte_per_pixel, unsigned char *tmp_buffer, int tmp_total_width, bool palette_flag )
{
if (dst_width == 0 || dst_height == 0) return;
unsigned char *tmp_buf = tmp_buffer;
unsigned char *src_buf = src_buffer;
int i, j, s;
int tmp_offset = tmp_total_width - src_width * byte_per_pixel;
unsigned int mx, my;
if ( src_width > 1 ) mx = 1;
else mx = 0;
if ( src_height > 1 ) my = 1;
else my = 0;
int interpolation_width = src_width / dst_width;
if ( interpolation_width == 0 ) interpolation_width = 1;
int interpolation_height = src_height / dst_height;
if ( interpolation_height == 0 ) interpolation_height = 1;
if (pixel_accum_size < src_width*byte_per_pixel){
pixel_accum_size = src_width*byte_per_pixel;
if (pixel_accum) delete[] pixel_accum;
pixel_accum = new unsigned long[pixel_accum_size];
if (pixel_accum_num) delete[] pixel_accum_num;
pixel_accum_num = new unsigned long[pixel_accum_size];
}
/* smoothing */
if ( byte_per_pixel >= 3 ){
calcWeightedSumColumnInit(&src_buf, interpolation_height,
src_width, src_height, src_total_width, byte_per_pixel );
for ( i=0 ; i<src_height ; i++ ){
calcWeightedSumColumn(&src_buf, i, interpolation_height,
src_width, src_height, src_total_width, byte_per_pixel );
for (s=0 ; s<byte_per_pixel ; s++){
tmp_acc[s]=0;
tmp_acc_num[s]=0;
for (j=0 ; j<-interpolation_width/2+interpolation_width-1 ; j++){
if (j >= src_width) break;
tmp_acc[s] += pixel_accum[src_width*s+j];
tmp_acc_num[s] += pixel_accum_num[src_width*s+j];
}
}
for ( j=0 ; j<src_width ; j++ )
calcWeightedSum(&tmp_buf, &src_buf, j,
interpolation_width,
src_width, byte_per_pixel );
tmp_buf += tmp_offset;
}
}
else{
tmp_buffer = src_buffer;
}
/* resampling */
unsigned char *dst_buf = dst_buffer;
int dh1 = dst_height-1; if (dh1==0) dh1 = 1;
int dw1 = dst_width-1; if (dw1==0) dw1 = 1;
for ( i=0 ; i<dst_height ; i++ ){
int y = (i<<3) * (src_height-1) / dh1;
int dy = y & 0x7;
y >>= 3;
for ( j=0 ; j<dst_width ; j++ ){
int x = (j<<3) * (src_width-1) / dw1;
int dx = x & 0x7;
x >>= 3;
int k = tmp_total_width * y + x * byte_per_pixel;
if (palette_flag){ //assuming byte_per_pixel=1
*dst_buf++ = tmp_buffer[k];
}
else{
for ( s=0 ; s<byte_per_pixel ; s++, k++ ){
unsigned int p;
p = (8-dx)*(8-dy)*tmp_buffer[ k ];
p += dx *(8-dy)*tmp_buffer[ k+mx*byte_per_pixel ];
p += (8-dx)* dy *tmp_buffer[ k+my*tmp_total_width ];
p += dx * dy *tmp_buffer[ k+mx*byte_per_pixel+my*tmp_total_width ];
*dst_buf++ = (unsigned char)(p>>6);
}
}
}
for ( j=0 ; j<dst_total_width - dst_width*byte_per_pixel ; j++ )
*dst_buf++ = 0;
}
/* pixels at the corners are preserved */
for ( i=0 ; i<byte_per_pixel ; i++ ){
dst_buffer[i] = src_buffer[i];
dst_buffer[(dst_width-1)*byte_per_pixel+i] = src_buffer[(src_width-1)*byte_per_pixel+i];
dst_buffer[(dst_height-1)*dst_total_width+i] = src_buffer[(src_height-1)*src_total_width+i];
dst_buffer[(dst_height-1)*dst_total_width+(dst_width-1)*byte_per_pixel+i] =
src_buffer[(src_height-1)*src_total_width+(src_width-1)*byte_per_pixel+i];
}
}
|