/**
* Function: gdImageCropAuto
*
* Crop an image automatically
*
* This function detects the cropping area according to the given _mode_.
*
* Parameters:
* im - The image.
* mode - The cropping mode, see <gdCropMode>.
*
* Returns:
* The newly created cropped image, or NULL on failure.
*
* See also:
* - <gdImageCrop>
* - <gdImageCropThreshold>
*/
BGD_DECLARE(gdImagePtr) gdImageCropAuto(gdImagePtr im, const unsigned int mode)
{
const int width = gdImageSX(im);
const int height = gdImageSY(im);
int x,y;
int color, match;
gdRect crop;
crop.x = 0;
crop.y = 0;
crop.width = 0;
crop.height = 0;
switch (mode) {
case GD_CROP_TRANSPARENT:
color = gdImageGetTransparent(im);
break;
case GD_CROP_BLACK:
color = gdImageColorClosestAlpha(im, 0, 0, 0, 0);
break;
case GD_CROP_WHITE:
color = gdImageColorClosestAlpha(im, 255, 255, 255, 0);
break;
case GD_CROP_SIDES:
gdGuessBackgroundColorFromCorners(im, &color);
break;
case GD_CROP_DEFAULT:
default:
color = gdImageGetTransparent(im);
break;
}
/* TODO: Add gdImageGetRowPtr and works with ptr at the row level
* for the true color and palette images
* new formats will simply work with ptr
*/
match = 1;
for (y = 0; match && y < height; y++) {
for (x = 0; match && x < width; x++) {
match = (color == gdImageGetPixel(im, x,y));
}
}
/* Whole image would be cropped > bye */
if (match) {
return NULL;
}
crop.y = y - 1;
match = 1;
for (y = height - 1; match && y >= 0; y--) {
for (x = 0; match && x < width; x++) {
match = (color == gdImageGetPixel(im, x,y));
}
}
crop.height = y - crop.y + 2;
match = 1;
for (x = 0; match && x < width; x++) {
for (y = 0; match && y < crop.y + crop.height; y++) {
match = (color == gdImageGetPixel(im, x,y));
}
}
crop.x = x - 1;
match = 1;
for (x = width - 1; match && x >= 0; x--) {
for (y = 0; match && y < crop.y + crop.height; y++) {
match = (color == gdImageGetPixel(im, x,y));
}
}
crop.width = x - crop.x + 2;
return gdImageCrop(im, &crop);
}
/**
* Function: gdImageAutoCrop
* Automatic croping of the src image using the given mode
* (see <gdCropMode>)
*
*
* Parameters:
* im - Source image
* mode - crop mode
*
* Returns:
* <gdImagePtr> on success or NULL
*
* See also:
* <gdCropMode>
*/
gdImagePtr gdImageCropAuto(gdImagePtr im, const unsigned int mode)
{
const int width = gdImageSX(im);
const int height = gdImageSY(im);
int x,y;
int color, corners, match;
gdRect crop;
crop.x = 0;
crop.y = 0;
crop.width = 0;
crop.height = 0;
switch (mode) {
case GD_CROP_TRANSPARENT:
color = gdImageGetTransparent(im);
break;
case GD_CROP_BLACK:
color = gdImageColorClosestAlpha(im, 0, 0, 0, 0);
break;
case GD_CROP_WHITE:
color = gdImageColorClosestAlpha(im, 255, 255, 255, 0);
break;
case GD_CROP_SIDES:
corners = gdGuessBackgroundColorFromCorners(im, &color);
break;
case GD_CROP_DEFAULT:
default:
color = gdImageGetTransparent(im);
if (color == -1) {
corners = gdGuessBackgroundColorFromCorners(im, &color);
}
break;
}
/* TODO: Add gdImageGetRowPtr and works with ptr at the row level
* for the true color and palette images
* new formats will simply work with ptr
*/
match = 1;
for (y = 0; match && y < height; y++) {
for (x = 0; match && x < width; x++) {
int c2 = gdImageGetPixel(im, x, y);
match = (color == c2);
}
}
/* Nothing to do > bye
* Duplicate the image?
*/
if (y == height - 1) {
return NULL;
}
crop.y = y -1;
match = 1;
for (y = height - 1; match && y >= 0; y--) {
for (x = 0; match && x < width; x++) {
match = (color == gdImageGetPixel(im, x,y));
}
}
if (y == 0) {
crop.height = height - crop.y + 1;
} else {
crop.height = y - crop.y + 2;
}
match = 1;
for (x = 0; match && x < width; x++) {
for (y = 0; match && y < crop.y + crop.height - 1; y++) {
match = (color == gdImageGetPixel(im, x,y));
}
}
crop.x = x - 1;
match = 1;
for (x = width - 1; match && x >= 0; x--) {
for (y = 0; match && y < crop.y + crop.height - 1; y++) {
match = (color == gdImageGetPixel(im, x,y));
}
}
crop.width = x - crop.x + 2;
if (crop.x <= 0 || crop.y <= 0 || crop.width <= 0 || crop.height <= 0) {
return NULL;
}
return gdImageCrop(im, &crop);
}
