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Diffstat (limited to 'include/mupdf/fitz/geometry.h')
| -rw-r--r-- | include/mupdf/fitz/geometry.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/include/mupdf/fitz/geometry.h b/include/mupdf/fitz/geometry.h index f04e8f1c..2314bea1 100644 --- a/include/mupdf/fitz/geometry.h +++ b/include/mupdf/fitz/geometry.h @@ -15,6 +15,14 @@ static inline int fz_mul255(int a, int b) } /* + Undo alpha premultiplication. +*/ +static inline int fz_div255(int c, int a) +{ + return a ? c * (255 * 256 / a) >> 8 : 0; +} + +/* Expand a value A from the 0...255 range to the 0..256 range */ #define FZ_EXPAND(A) ((A)+((A)>>7)) |