VidOilTank/image.c

#include "vidoiltank.h"

#define copypixel(_DEST_, _SRC_) 	*(_DEST_ + 0) = *(_SRC_ + 0); \
									*(_DEST_ + 1) = *(_SRC_ + 1); \
									*(_DEST_ + 2) = *(_SRC_ + 2);

ImageRaw *image_alloc (int w, int h) {
	ImageRaw *i = NULL;

	i = (ImageRaw *) malloc (sizeof (ImageRaw));
	i->size = w*h*3;
	i->data = malloc(i->size);
	i->w = w;
	i->h = h;

	return i;
};


void image_resize(ImageRaw *i, int w, int h) {
	if (i == NULL) {
		printf ("error: image_resize .. image points to NULL\n");
		exit (1);
	}

	free (i->data);
	i->size = w*h*3;
	i->data = malloc(i->size);
	i->w = w;
	i->h = h;
};


int image_save(ImageRaw *i, char *fn, int quality) {
  struct jpeg_compress_struct cinfo;
  struct jpeg_error_mgr jerr;
  FILE * outfile;		/* target file */
  JSAMPROW row_pointer[1];	/* pointer to JSAMPLE row[s] */
  int row_stride;		/* physical row width in image buffer */

  if (i == NULL) {
	  printf ("image_save no image i == NULL\n");
	  exit (1);
  }

  cinfo.err = jpeg_std_error(&jerr);
  jpeg_create_compress(&cinfo);

  if ((outfile = fopen(fn, "wb")) == NULL) {
	fprintf(stderr, "can't open %s\n", fn);
	exit(1);
  }
  jpeg_stdio_dest(&cinfo, outfile);

  cinfo.image_width = i->w; 	/* image width and height, in pixels */
  cinfo.image_height = i->h;
  cinfo.input_components = 3;		/* # of color components per pixel */
  cinfo.in_color_space = JCS_RGB; 	/* colorspace of input image */
  jpeg_set_defaults(&cinfo);
  jpeg_set_quality(&cinfo, quality, TRUE /* limit to baseline-JPEG values */);
  jpeg_start_compress(&cinfo, TRUE);
  row_stride = i->w * 3;	/* JSAMPLEs per row in image_buffer */

  while (cinfo.next_scanline < cinfo.image_height) {
	row_pointer[0] = & i->data[cinfo.next_scanline * row_stride];
	(void) jpeg_write_scanlines(&cinfo, row_pointer, 1);
  }

  jpeg_finish_compress(&cinfo);
  fclose(outfile);
  jpeg_destroy_compress(&cinfo);

  return 0;
};

void image_rotate (ImageRaw *img, int deg) {
	if (img == NULL || img->data == NULL) return;
	if (deg == 0) return;

	if (deg == 90 || deg == 270) {
		int nx, ny, x, y;
		int nw = img->h;
		int nh = img->w;
		unsigned char *old = img->data;
		unsigned char *new = malloc (3 * img->w * img->h);

		for (y = 0; y < img->h; y++) for (x = 0; x < img->w; x++) {
			if (deg == 90) {
				nx = img->h - y -1;
				ny = x;
			}
			else {
				nx = y;
				ny = img->w - x - 1;
			}
			copypixel(new+3*(nx + ny * nw), old+3*(x + y * img->w));
		}

		img->w = nw;
		img->h = nh;
		img->data = new;
		free (old);
	}
	else if (deg == 180) {
		int x, y, nx, ny;
		unsigned char pixel[3];
		for (y = 0; y < (img->h/2); y++) for (x = 0; x < img->w; x++) {
			nx = img->w - x - 1;
			ny = img->h - y - 1;
			copypixel(pixel, img->data+3*(nx + ny * img->w));
			copypixel(img->data+3*(nx + ny * img->w), img->data+3*(x + y * img->w));
			copypixel(img->data+3*(x + y * img->w), pixel);
		}
	}
};


void image_draw_pixel (ImageRaw *img, int x, int y, int col) {
	if (img == NULL || img->data == NULL) return;
	if (x < 0 || x >= img->w) return;
	if (y < 0 || y >= img->h) return;

	memcpy (img->data+3*(x+y*img->w), &col, 3);
}


void image_draw_rect (ImageRaw *img, Rect *r, int col) {
	if (r == NULL || img == NULL || img->data == NULL) return;
	if (r->x + r->w > img->w || r->y + r->h > img->h) return;
	int x, y;

	for (x = 0; x < r->w && x + r->x < img->w; x++) {
		image_draw_pixel (img, x, r->y, col);
		image_draw_pixel (img, x, r->y+r->h-1, col);
	}
	for (y = 0; y < r->h && y + r->y < img->h; y++) {
		image_draw_pixel (img, r->x, y, col);
		image_draw_pixel (img, r->x + r->w - 1, y, col);
	}
}


void image_get_minmax (ImageRaw *img, Rect *r, int *min, int *max) {
	int x, y, l, cr, cg, cb;
	if (img == NULL || img->data == NULL) return;

	cr = (unsigned char)*(img->data+0+3*(r->x+r->y*img->w));
	cg = (unsigned char)*(img->data+1+3*(r->x+r->y*img->w));
	cb = (unsigned char)*(img->data+2+3*(r->x+r->y*img->w));
	*min = *max = cr + cg + cb;

	for (x = r->x; x < (r->x+r->w) && x < img->w; x++)
		for (y = r->y; y < (r->w + r->h) && y < img->h; y++) {
			cr = (unsigned char)*(img->data+0+3*(x+y*img->w));
			cg = (unsigned char)*(img->data+1+3*(x+y*img->w));
			cb = (unsigned char)*(img->data+2+3*(x+y*img->w));
//			printf ("%d %d %d\n", cr, cg, cb);
			l = cr + cg + cb;
			if (l < *min) *min = l;
			if (l > *max) *max = l;
		}
}



ImageFloat *imageF_alloc (int w, int h) {
	ImageFloat *i = NULL;

	i = (ImageFloat *) malloc (sizeof (ImageFloat));
	i->size = w*h*sizeof(float);
	i->data = (float *)malloc(i->size);
	i->w = w;
	i->h = h;

	return i;
};


ImageFloat *imageF_copy(ImageRaw *iraw, Rect *r) {
	ImageFloat *ifloat = imageF_alloc(r->w, r->h);
	int x, y;
	float f;

	for (y = 0; y < r->h; y++) for (x = 0; x < r->w; x++) {
		f = *(iraw->data+0+3*(r->x + x + (r->y + y)*iraw->w)) +
			*(iraw->data+1+3*(r->x + x + (r->y + y)*iraw->w)) +
			*(iraw->data+2+3*(r->x + x + (r->y + y)*iraw->w));
		f = f/3.0;
		*(ifloat->data+(x+y*ifloat->w)) = f;
	}

	return ifloat;
};

void imageF_add(ImageFloat *ifloat, ImageRaw *iraw, Rect *r) {
	int x, y;
	float f;

	for (y = 0; y < r->h; y++) for (x = 0; x < r->w; x++) {
		f = *(iraw->data+0+3*(r->x + x + (r->y + y)*iraw->w)) +
			*(iraw->data+1+3*(r->x + x + (r->y + y)*iraw->w)) +
			*(iraw->data+2+3*(r->x + x + (r->y + y)*iraw->w));
		f = f/3.0;
		*(ifloat->data+(x+y*ifloat->w)) += f;
	}
};



ImageRaw *image_copyF(ImageFloat *ifloat) {
	ImageRaw *iraw = image_alloc(ifloat->w, ifloat->h);
	int x, y;
	int min, max;
	unsigned char c;

	// get limit
	min = max = *(ifloat->data);
	for (y = 0; y < ifloat->h; y++) for (x = 0; x < ifloat->w; x++) {
		if (*(ifloat->data+(x+y*ifloat->w)) < min)
			min = *(ifloat->data+(x+y*ifloat->w));
		if (*(ifloat->data+(x+y*ifloat->w)) > max)
			max = *(ifloat->data+(x+y*ifloat->w));
	}

	for (y = 0; y < ifloat->h; y++) for (x = 0; x < ifloat->w; x++) {
		c = (255.0 * (*(ifloat->data+(x+y*ifloat->w)) - min) / (max - min));
		*(iraw->data+0+3*(x + y * iraw->w)) = c;
		*(iraw->data+1+3*(x + y * iraw->w)) = c;
		*(iraw->data+2+3*(x + y * iraw->w)) = c;
	}

	return iraw;
};