openmv/src/omv/imlib/pool.c

150 lines
7.1 KiB
C

/*
* This file is part of the OpenMV project.
* Copyright (c) 2013-2016 Kwabena W. Agyeman <kwagyeman@openmv.io>
* This work is licensed under the MIT license, see the file LICENSE for details.
*
* Image pooling.
*
*/
#include "imlib.h"
#ifdef IMLIB_ENABLE_MIDPOINT_POOLING
void imlib_midpoint_pool(image_t *img_i, image_t *img_o, int x_div, int y_div, const int bias) {
int min_bias = (256 - bias);
int max_bias = bias;
switch (img_i->pixfmt) {
case PIXFORMAT_BINARY: {
for (int y = 0, yy = img_i->h / y_div, yyy = (img_i->h % y_div) / 2; y < yy; y++) {
uint32_t *row_ptr = IMAGE_COMPUTE_BINARY_PIXEL_ROW_PTR(img_o, y);
for (int x = 0, xx = img_i->w / x_div, xxx = (img_i->w % x_div) / 2; x < xx; x++) {
int min = COLOR_BINARY_MAX, max = COLOR_BINARY_MIN;
for (int i = 0; i < y_div; i++) {
for (int j = 0; j < x_div; j++) {
int pixel = IMAGE_GET_BINARY_PIXEL(img_i, xxx + (x * x_div) + j, yyy + (y * y_div) + i);
min = IM_MIN(min, pixel);
max = IM_MAX(max, pixel);
}
}
IMAGE_PUT_BINARY_PIXEL_FAST(row_ptr, x,
((min * min_bias) + (max * max_bias)) >> 8);
}
}
break;
}
case PIXFORMAT_GRAYSCALE: {
for (int y = 0, yy = img_i->h, yyy = (img_i->h % y_div) / 2; y < yy; y++) {
uint8_t *row_ptr = IMAGE_COMPUTE_GRAYSCALE_PIXEL_ROW_PTR(img_o, y);
for (int x = 0, xx = img_i->w / x_div, xxx = (img_i->w % x_div) / 2; x < xx; x++) {
int min = COLOR_GRAYSCALE_MAX, max = COLOR_GRAYSCALE_MIN;
for (int i = 0; i < y_div; i++) {
for (int j = 0; j < x_div; j++) {
int pixel = IMAGE_GET_GRAYSCALE_PIXEL(img_i, xxx + (x * x_div) + j, yyy + (y * y_div) + i);
min = IM_MIN(min, pixel);
max = IM_MAX(max, pixel);
}
}
IMAGE_PUT_GRAYSCALE_PIXEL_FAST(row_ptr, x,
((min * min_bias) + (max * max_bias)) >> 8);
}
}
break;
}
case PIXFORMAT_RGB565: {
for (int y = 0, yy = img_i->h / y_div, yyy = (img_i->h % y_div) / 2; y < yy; y++) {
uint16_t *row_ptr = IMAGE_COMPUTE_RGB565_PIXEL_ROW_PTR(img_o, y);
for (int x = 0, xx = img_i->w / x_div, xxx = (img_i->w % x_div) / 2; x < xx; x++) {
int r_min = COLOR_R5_MAX, r_max = COLOR_R5_MIN;
int g_min = COLOR_G6_MAX, g_max = COLOR_G6_MIN;
int b_min = COLOR_B5_MAX, b_max = COLOR_B5_MIN;
for (int i = 0; i < y_div; i++) {
for (int j = 0; j < x_div; j++) {
const uint16_t pixel = IM_GET_RGB565_PIXEL(img_i, xxx + (x * x_div) + j, yyy + (y * y_div) + i);
int r = COLOR_RGB565_TO_R5(pixel);
int g = COLOR_RGB565_TO_G6(pixel);
int b = COLOR_RGB565_TO_B5(pixel);
r_min = IM_MIN(r_min, r);
r_max = IM_MAX(r_max, r);
g_min = IM_MIN(g_min, g);
g_max = IM_MAX(g_max, g);
b_min = IM_MIN(b_min, b);
b_max = IM_MAX(b_max, b);
}
}
IMAGE_PUT_RGB565_PIXEL_FAST(row_ptr, x,
COLOR_R5_G6_B5_TO_RGB565(((r_min * min_bias) + (r_max * max_bias)) >> 8,
((g_min * min_bias) + (g_max * max_bias)) >> 8,
((b_min * min_bias) + (b_max * max_bias)) >> 8));
}
}
break;
}
default: {
break;
}
}
}
#endif // IMLIB_ENABLE_MIDPOINT_POOLING
#ifdef IMLIB_ENABLE_MEAN_POOLING
void imlib_mean_pool(image_t *img_i, image_t *img_o, int x_div, int y_div) {
int n = x_div * y_div;
switch (img_i->pixfmt) {
case PIXFORMAT_BINARY: {
for (int y = 0, yy = img_i->h / y_div, yyy = (img_i->h % y_div) / 2; y < yy; y++) {
uint32_t *row_ptr = IMAGE_COMPUTE_BINARY_PIXEL_ROW_PTR(img_o, y);
for (int x = 0, xx = img_i->w / x_div, xxx = (img_i->w % x_div) / 2; x < xx; x++) {
int acc = 0;
for (int i = 0; i < y_div; i++) {
for (int j = 0; j < x_div; j++) {
int pixel = IMAGE_GET_BINARY_PIXEL(img_i, xxx + (x * x_div) + j, yyy + (y * y_div) + i);
acc += pixel;
}
}
IMAGE_PUT_BINARY_PIXEL_FAST(row_ptr, x, acc / n);
}
}
break;
}
case PIXFORMAT_GRAYSCALE: {
for (int y = 0, yy = img_i->h / y_div, yyy = (img_i->h % y_div) / 2; y < yy; y++) {
uint8_t *row_ptr = IMAGE_COMPUTE_GRAYSCALE_PIXEL_ROW_PTR(img_o, y);
for (int x = 0, xx = img_i->w / x_div, xxx = (img_i->w % x_div) / 2; x < xx; x++) {
int acc = 0;
for (int i = 0; i < y_div; i++) {
for (int j = 0; j < x_div; j++) {
int pixel = IMAGE_GET_GRAYSCALE_PIXEL(img_i, xxx + (x * x_div) + j, yyy + (y * y_div) + i);
acc += pixel;
}
}
IMAGE_PUT_GRAYSCALE_PIXEL_FAST(row_ptr, x, acc / n);
}
}
break;
}
case PIXFORMAT_RGB565: {
for (int y = 0, yy = img_i->h / y_div, yyy = (img_i->h % y_div) / 2; y < yy; y++) {
uint16_t *row_ptr = IMAGE_COMPUTE_RGB565_PIXEL_ROW_PTR(img_o, y);
for (int x = 0, xx = img_i->w / x_div, xxx = (img_i->w % x_div) / 2; x < xx; x++) {
int r_acc = 0;
int g_acc = 0;
int b_acc = 0;
for (int i = 0; i < y_div; i++) {
for (int j = 0; j < x_div; j++) {
int pixel = IMAGE_GET_RGB565_PIXEL(img_i, xxx + (x * x_div) + j, yyy + (y * y_div) + i);
r_acc += COLOR_RGB565_TO_R5(pixel);
g_acc += COLOR_RGB565_TO_G6(pixel);
b_acc += COLOR_RGB565_TO_B5(pixel);
}
}
IMAGE_PUT_RGB565_PIXEL_FAST(row_ptr, x, COLOR_R5_G6_B5_TO_RGB565(r_acc / n, g_acc / n, b_acc / n));
}
}
break;
}
default: {
break;
}
}
}
#endif // IMLIB_ENABLE_MEAN_POOLING