/* set pixels that have at least mask pixels around it set (including the
* examined pixel itself) to black (foreground), all other pixels to white
* (background) */
Imlib_Image set_pixels_filter(Imlib_Image *source_image, double thresh,
luminance_t lt, int mask)
{
Imlib_Image new_image; /* construct filtered image here */
Imlib_Image current_image; /* save image pointer */
int height, width; /* image dimensions */
int x,y,i,j; /* iteration variables */
int set_pixel; /* should pixel be set or not? */
Imlib_Color color;
int lum; /* luminance value of pixel */
/* save pointer to current image */
current_image = imlib_context_get_image();
/* create a new image */
imlib_context_set_image(*source_image);
height = imlib_image_get_height();
width = imlib_image_get_width();
new_image = imlib_clone_image();
/* check for every pixel if it should be set in filtered image */
for(x=0; x<width; x++) {
for(y=0; y<height; y++) {
set_pixel=0;
for(i=x-1; i<=x+1; i++) {
for(j=y-1; j<=y+1; j++) {
if(i>=0 && i<width && j>=0 && j<height) { /* i,j inside image? */
imlib_image_query_pixel(i, j, &color);
lum = get_lum(&color, lt);
if(is_pixel_set(lum, thresh)) {
set_pixel++;
}
}
}
}
/* set pixel if at least mask pixels around it are set */
if(set_pixel >= mask) {
draw_fg_pixel(new_image, x, y);
} else {
draw_bg_pixel(new_image, x, y);
}
}
}
/* restore image from before function call */
imlib_context_set_image(current_image);
/* return filtered image */
return new_image;
}
/* compute dynamic threshold value from the rectangle (x,y),(x+w,y+h) of
* source_image */
double get_threshold(Imlib_Image *source_image, double fraction, luminance_t lt,
int x, int y, int w, int h)
{
Imlib_Image current_image; /* save image pointer */
int height, width; /* image dimensions */
int xi,yi; /* iteration variables */
Imlib_Color color;
int lum; /* luminance of pixel */
double minval=(double)MAXRGB, maxval=0.0;
/* save pointer to current image */
current_image = imlib_context_get_image();
/* get image dimensions */
imlib_context_set_image(*source_image);
height = imlib_image_get_height();
width = imlib_image_get_width();
/* special value -1 for width or height means image width/height */
if(w == -1) w = width;
if(h == -1) h = width;
/* assure valid coordinates */
if(x+w > width) x = width-w;
if(y+h > height) y = height-h;
if(x<0) x=0;
if(y<0) y=0;
/* find the threshold value to differentiate between dark and light */
for(xi=0; (xi<w) && (xi<width); xi++) {
for(yi=0; (yi<h) && (yi<height); yi++) {
imlib_image_query_pixel(x+xi, y+yi, &color);
lum = get_lum(&color, lt);
if(lum < minval) minval = lum;
if(lum > maxval) maxval = lum;
}
}
/* restore image from before function call */
imlib_context_set_image(current_image);
return (minval + fraction * (maxval - minval)) * 100 / MAXRGB;
}
/* get maximum luminance value */
double get_maxval(Imlib_Image *source_image, int x, int y, int w, int h,
luminance_t lt)
{
Imlib_Image current_image; /* save image pointer */
int height, width; /* image dimensions */
int xi,yi; /* iteration variables */
Imlib_Color color; /* Imlib2 RGBA color structure */
int lum = 0;
int maxval = 0;
/* save pointer to current image */
current_image = imlib_context_get_image();
/* get image dimensions */
imlib_context_set_image(*source_image);
height = imlib_image_get_height();
width = imlib_image_get_width();
/* special value -1 for width or height means image width/height */
if(w == -1) w = width;
if(h == -1) h = width;
/* assure valid coordinates */
if(x+w > width) x = width-w;
if(y+h > height) y = height-h;
if(x<0) x=0;
if(y<0) y=0;
/* find the minimum value in the image */
for(xi=0; (xi<w) && (xi<width); xi++) {
for(yi=0; (yi<h) && (yi<height); yi++) {
imlib_image_query_pixel(xi, yi, &color);
lum = clip(get_lum(&color, lt),0,255);
if(lum > maxval) maxval = lum;
}
}
/* restore image from before function call */
imlib_context_set_image(current_image);
return maxval;
}
int main(int ac, char **av)
{
t_lum *tab_lum;
t_pos test;
t_win mlxwin;
ac != 4 ? exit (1) : 0;
(mlxwin.mlx = mlx_init()) == NULL ? exit (1) : 0;
(mlxwin.win = mlx_new_window(mlxwin.mlx, 1000, 1000, "RTV1")) == NULL ?\
exit (1) : 0;
(mlxwin.img = mlx_new_image(mlxwin.mlx, 1000, 1000)) == NULL ? exit (1) : 0;
get_eye(&mlxwin, av[1]);
mlxwin.tab_obj = get_obj(av[2]);
mlxwin.tab_lum = get_lum(av[3]);
remplis_image(&mlxwin);
mlx_key_hook(mlxwin.win, gere_key, &mlxwin);
mlx_expose_hook(mlxwin.win, gere_expose, &mlxwin);
mlx_loop(mlxwin.mlx);
return (0);
}
void get_light(t_scene *s, t_intersect *inter, double *col)
{
int i;
int m;
double max;
double total;
i = m = -1;
while (++i < 3)
col[i] = s->spec.bg_color.argb[i] / 255.0 * s->spec.ambiant;
max = total = 0;
while (++m < s->nb_light)
{
get_lum(col, s, inter, m);
max = MAX(s->lights[m].light.power, max);
total += s->lights[m].light.power;
}
i = -1;
while (++i < 3)
col[i] /= total / max;
}
/* ww and wh are the width and height of the rectangle used to find the
* threshold value */
Imlib_Image dynamic_threshold(Imlib_Image *source_image,double t,luminance_t lt,
int ww, int wh)
{
Imlib_Image new_image; /* construct filtered image here */
Imlib_Image current_image; /* save image pointer */
int height, width; /* image dimensions */
int x,y; /* iteration variables */
Imlib_Color color;
int lum;
double thresh;
/* save pointer to current image */
current_image = imlib_context_get_image();
/* create a new image */
imlib_context_set_image(*source_image);
height = imlib_image_get_height();
width = imlib_image_get_width();
new_image = imlib_clone_image();
/* check for every pixel if it should be set in filtered image */
for(x=0; x<width; x++) {
for(y=0; y<height; y++) {
imlib_image_query_pixel(x, y, &color);
lum = get_lum(&color, lt);
thresh = get_threshold(source_image, t/100.0, lt, x-ww/2, y-ww/2, ww, wh);
if(is_pixel_set(lum, thresh)) {
draw_fg_pixel(new_image, x, y);
} else {
draw_bg_pixel(new_image, x, y);
}
}
}
/* restore image from before function call */
imlib_context_set_image(current_image);
/* return filtered image */
return new_image;
}
/* turn image to grayscale */
Imlib_Image grayscale(Imlib_Image *source_image, luminance_t lt)
{
Imlib_Image new_image; /* construct grayscale image here */
Imlib_Image current_image; /* save image pointer */
int height, width; /* image dimensions */
int x,y; /* iteration variables */
Imlib_Color color; /* Imlib2 color structure */
int lum=0;
/* save pointer to current image */
current_image = imlib_context_get_image();
/* create a new image */
imlib_context_set_image(*source_image);
height = imlib_image_get_height();
width = imlib_image_get_width();
new_image = imlib_clone_image();
/* transform image to grayscale */
for(x=0; x<width; x++) {
for(y=0; y<height; y++) {
imlib_context_set_image(*source_image);
imlib_image_query_pixel(x, y, &color);
imlib_context_set_image(new_image);
lum = clip(get_lum(&color, lt),0,255);
imlib_context_set_color(lum, lum, lum, color.alpha);
imlib_image_draw_pixel(x, y, 0);
}
}
/* restore image from before function call */
imlib_context_set_image(current_image);
/* return filtered image */
return new_image;
}
/* determine threshold by an iterative method */
double iterative_threshold(Imlib_Image *source_image, double thresh,
luminance_t lt, int x, int y, int w, int h)
{
Imlib_Image current_image; /* save image pointer */
int height, width; /* image dimensions */
int xi,yi; /* iteration variables */
Imlib_Color color;
int lum; /* luminance of pixel */
unsigned int size_white, size_black; /* size of black and white groups */
unsigned long int sum_white, sum_black; /* sum of black and white groups */
unsigned int avg_white, avg_black; /* average values of black and white */
double old_thresh; /* old threshold computed by last iteration step */
double new_thresh; /* new threshold computed by current iteration step */
int thresh_lum; /* luminance value of threshold */
/* normalize threshold (was given as a percentage) */
new_thresh = thresh / 100.0;
/* save pointer to current image */
current_image = imlib_context_get_image();
/* get image dimensions */
imlib_context_set_image(*source_image);
height = imlib_image_get_height();
width = imlib_image_get_width();
/* special value -1 for width or height means image width/height */
if(w == -1) w = width;
if(h == -1) h = width;
/* assure valid coordinates */
if(x+w > width) x = width-w;
if(y+h > height) y = height-h;
if(x<0) x=0;
if(y<0) y=0;
/* find the threshold value to differentiate between dark and light */
do {
thresh_lum = MAXRGB * new_thresh;
old_thresh = new_thresh;
size_black = sum_black = size_white = sum_white = 0;
for(xi=0; (xi<w) && (xi<width); xi++) {
for(yi=0; (yi<h) && (yi<height); yi++) {
imlib_image_query_pixel(xi, yi, &color);
lum = get_lum(&color, lt);
if(lum <= thresh_lum) {
size_black++;
sum_black += lum;
} else {
size_white++;
sum_white += lum;
}
}
}
if(!size_white) {
fprintf(stderr, "iterative_threshold(): error: no white pixels\n");
imlib_context_set_image(current_image);
return thresh;
}
if(!size_black) {
fprintf(stderr, "iterative_threshold(): error: no black pixels\n");
imlib_context_set_image(current_image);
return thresh;
}
avg_white = sum_white / size_white;
avg_black = sum_black / size_black;
new_thresh = (avg_white + avg_black) / (2.0 * MAXRGB);
/*fprintf(stderr, "iterative_threshold(): new_thresh = %f\n", new_thresh);*/
} while(fabs(new_thresh - old_thresh) > EPSILON);
/* restore image from before function call */
imlib_context_set_image(current_image);
return new_thresh * 100;
}
/* gray stretching, i.e. lum<t1 => lum=0, lum>t2 => lum=100,
* else lum=((lum-t1)*MAXRGB)/(t2-t1) */
Imlib_Image gray_stretch(Imlib_Image *source_image, double t1, double t2,
luminance_t lt)
{
Imlib_Image new_image; /* construct filtered image here */
Imlib_Image current_image; /* save image pointer */
int height, width; /* image dimensions */
int x,y; /* iteration variables */
Imlib_Color color;
int lum; /* luminance value of pixel */
/* do nothing if t1>=t2 */
if(t1 >= t2) {
fprintf(stderr, "error: gray_stretch(): t1=%.2f >= t2=%.2f\n", t1, t2);
exit(99);
}
/* check if 0 < t1,t2 < MAXRGB */
if(t1 <= 0.0) {
fprintf(stderr, "error: gray_stretch(): t1=%.2f <= 0.0\n", t1);
exit(99);
}
if(t2 >= MAXRGB) {
fprintf(stderr, "error: gray_stretch(): t2=%.2f >= %d.0\n", t2, MAXRGB);
exit(99);
}
/* save pointer to current image */
current_image = imlib_context_get_image();
/* create a new image */
imlib_context_set_image(*source_image);
height = imlib_image_get_height();
width = imlib_image_get_width();
new_image = imlib_clone_image();
/* gray stretch image */
for(x=0; x<width; x++) {
for(y=0; y<height; y++) {
imlib_image_query_pixel(x, y, &color);
lum = get_lum(&color, lt);
imlib_context_set_image(new_image);
if(lum<=t1) {
imlib_context_set_color(0, 0, 0, color.alpha);
} else if(lum>=t2) {
imlib_context_set_color(MAXRGB, MAXRGB, MAXRGB, color.alpha);
} else {
imlib_context_set_color(clip(((lum-t1)*255)/(t2-t1),0,255),
clip(((lum-t1)*255)/(t2-t1),0,255),
clip(((lum-t1)*255)/(t2-t1),0,255),
color.alpha);
}
imlib_image_draw_pixel(x, y, 0);
imlib_context_set_image(*source_image);
}
}
/* restore image from before function call */
imlib_context_set_image(current_image);
/* return filtered image */
return new_image;
}
