diff options
| author | Laurent Pinchart <laurent.pinchart@ideasonboard.com> | 2021-12-06 16:21:19 +0200 |
|---|---|---|
| committer | Laurent Pinchart <laurent.pinchart@ideasonboard.com> | 2021-12-07 19:09:31 +0200 |
| commit | f413f944d789911c9ded831ac45a7674c129ceba (patch) | |
| tree | c09d9d0e96e9e504d3a35c7d02e5c31d33908b1b /include | |
| parent | 72679c682eb0b9f03948f258a26f78c037d33c48 (diff) | |
libcamera: base: utils: Add abs_diff() utility function
The abs_diff() function computes the absolute difference of two
elements. This may seem trivial at first, but can lead to unexpected
results when operating on unsigned operands. A common implementation
of the absolute difference of two unsigned int (used through the
libcamera code base) is
std::abs(static_cast<int>(a - b))
but doesn't return the expected result when either a or b is larger than
UINT_MAX / 2 due to overflows. The abs_diff() function offers a safe
alternative.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Umang Jain <umang.jain@ideasonboard.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/libcamera/base/utils.h | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/include/libcamera/base/utils.h b/include/libcamera/base/utils.h index 3a803176..9ab18101 100644 --- a/include/libcamera/base/utils.h +++ b/include/libcamera/base/utils.h @@ -346,6 +346,15 @@ public: } }; +template<typename T> +decltype(auto) abs_diff(const T &a, const T &b) +{ + if (a < b) + return b - a; + else + return a - b; +} + } /* namespace utils */ #ifndef __DOXYGEN__ |