Mathis/sharp
1
0
Fork 0
mirror of https://github.com/lovell/sharp.git synced 2025-12-19 07:15:08 +01:00
Code Issues Packages Projects Releases Wiki Activity

Use bounding box of alpha+non-alpha for trim op #2166

Browse Source
This commit is contained in:
Lovell Fuller
2022-07-05 18:19:17 +01:00
parent e3cab7f10f
commit e0d3c6e05d
8 changed files with 44 additions and 14 deletions
Download Patch File Download Diff File Expand all files Collapse all files

34
src/operations.cc
View File

@@ -275,18 +275,30 @@ namespace sharp {
left = image.find_trim(&top, &width, &height, VImage::option()
->set("background", background(0, 0))
->set("threshold", threshold));
if (HasAlpha(image)) {
// Search alpha channel (A)
int leftA, topA, widthA, heightA;
VImage alpha = image[image.bands() - 1];
VImage backgroundAlpha = alpha.extract_area(0, 0, 1, 1);
leftA = alpha.find_trim(&topA, &widthA, &heightA, VImage::option()
->set("background", backgroundAlpha(0, 0))
->set("threshold", threshold));
if (widthA > 0 && heightA > 0) {
if (width > 0 && height > 0) {
// Combined bounding box (B)
int const leftB = std::min(left, leftA);
int const topB = std::min(top, topA);
int const widthB = std::max(left + width, leftA + widthA) - leftB;
int const heightB = std::max(top + height, topA + heightA) - topB;
return image.extract_area(leftB, topB, widthB, heightB);
} else {
// Use alpha only
return image.extract_area(leftA, topA, widthA, heightA);
}
}
}
if (width == 0 || height == 0) {
if (HasAlpha(image)) {
// Search alpha channel
VImage alpha = image[image.bands() - 1];
VImage backgroundAlpha = alpha.extract_area(0, 0, 1, 1);
left = alpha.find_trim(&top, &width, &height, VImage::option()
->set("background", backgroundAlpha(0, 0))
->set("threshold", threshold));
}
if (width == 0 || height == 0) {
throw VError("Unexpected error while trimming. Try to lower the tolerance");
}
throw VError("Unexpected error while trimming. Try to lower the tolerance");
}
return image.extract_area(left, top, width, height);
}