Way to translation of Mat class operators defined in C++
This is a list of implemented matrix operations that can be combined in arbitrary complex expressions (here A, B stand for matrices ( Mat ), s for a scalar ( Scalar ), alpha for a real-valued scalar ( double )):
In c#, it is not possible to explicitly overload compound assignment operators such as “A *= B“. Instead, binary operator overloading is used implicitly. Therefore, whenever an operator is used, a new mat is created and assigned.
| c++ | OpenCVForUnity(C#) | |
|---|---|---|
| Addition, subtraction, negation: A+B, A-B, A+s, A-s, s+A, s-A, -A | ||
| A + B | M1 + M2 | Core.add (M1, M2, M_dst) |
| A – B | M1 – M2 | Core.subtract (M1, M2, M_dst) |
| A + s | M1 + s | Core.add (M1, s, M_dst) |
| A – s | M1 – s | Core.subtract (M1, s, M_dst) |
| -A | -M1 | Core.multiply (M1, Scalar.all (-1), M_dst) |
| Scaling: A*alpha A/alpha | ||
| A * α | M1 * 3 | Core.multiply (M1, Scalar.all (3), M_dst) |
| A / α | M1 / 3 | Core.divide (M1, Scalar.all (3), M_dst) |
| Per-element multiplication and division: A.mul(B), A/B, alpha/A | ||
| A.mul(B) | M1.mul(M2) | M1.mul (M2) |
| A / B | M1 / M2 | Core.divide (M1, M2, M_dst) |
| α / A | 3 / M1 | Core.divide (new Mat (M1.size (), M1.type (), Scalar.all (3)), M1, M_dst) |
| Matrix multiplication: A*B | ||
| A * B | M1 * M2 | Core.gemm (M1, M2, 1, new Mat (), 0, M_dst) |
| Comparison: A cmpop B, A cmpop alpha, alpha cmpop A, where cmpop is one of : >, >=, ==, !=, <=, <. The result of comparison is an 8-bit single channel mask whose elements are set to 255 (if the particular element or pair of elements satisfy the condition) or 0. | ||
| A > B | M1 > M2 | Core.compare (M1, M2, M_dst, Core.CMP_GT) |
| A >= B | M1 >= M2 | Core.compare (M1, M2, M_dst, Core.CMP_GE) |
| A == B | M1 == M2 | Core.compare (M1, M2, M_dst, Core.CMP_EQ) |
| A != B | M1 != M2 | Core.compare (M1, M2, M_dst, Core.CMP_NE) |
| A <= B | M1 <= M2 | Core.compare (M1, M2, M_dst, Core.CMP_LE) |
| A < B | M1 < M2 | Core.compare (M1, M2, M_dst, Core.CMP_LT) |
| Bitwise logical operations: A logicop B, A logicop s, s logicop A, ~A, where logicop is one of : &, |, ^. | ||
| A & B | M1 & M2 | Core.bitwise_and (M1, M2, M_dst) |
| A | B | M1 | M2 | Core.bitwise_or (M1, M2, M_dst) |
| A ^ B | M1 ^ M2 | Core.bitwise_xor (M1, M2, M_dst) |
| ~A | ~M1 | Core.bitwise_not (M1, M_dst) |
| Matrix assignment operators: | ||
| C = A + B | M3 = M1 + M2 | Core.add (M1, M2, M3) |
| A = s | M1 = s | M1.setTo (s) |
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