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- /*
- * Copyright 2012 ZXing authors
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
- @class ZXGenericGFPoly;
-
- /**
- * This class contains utility methods for performing mathematical operations over
- * the Galois Fields. Operations use a given primitive polynomial in calculations.
- *
- * Throughout this package, elements of the GF are represented as an int
- * for convenience and speed (but at the cost of memory).
- */
- @interface ZXGenericGF : NSObject
-
- @property (nonatomic, strong, readonly) ZXGenericGFPoly *zero;
- @property (nonatomic, strong, readonly) ZXGenericGFPoly *one;
- @property (nonatomic, assign, readonly) int32_t size;
- @property (nonatomic, assign, readonly) int32_t generatorBase;
-
- + (ZXGenericGF *)AztecData12;
- + (ZXGenericGF *)AztecData10;
- + (ZXGenericGF *)AztecData6;
- + (ZXGenericGF *)AztecParam;
- + (ZXGenericGF *)QrCodeField256;
- + (ZXGenericGF *)DataMatrixField256;
- + (ZXGenericGF *)AztecData8;
- + (ZXGenericGF *)MaxiCodeField64;
-
- /**
- * Create a representation of GF(size) using the given primitive polynomial.
- *
- * @param primitive irreducible polynomial whose coefficients are represented by
- * the bits of an int, where the least-significant bit represents the constant
- * coefficient
- * @param size the size of the field
- * @param b the factor b in the generator polynomial can be 0- or 1-based
- * (g(x) = (x+a^b)(x+a^(b+1))...(x+a^(b+2t-1))).
- * In most cases it should be 1, but for QR code it is 0.
- */
- - (id)initWithPrimitive:(int)primitive size:(int)size b:(int)b;
-
- /**
- * @return the monomial representing coefficient * x^degree
- */
- - (ZXGenericGFPoly *)buildMonomial:(int)degree coefficient:(int)coefficient;
-
- /**
- * Implements both addition and subtraction -- they are the same in GF(size).
- *
- * @return sum/difference of a and b
- */
- + (int32_t)addOrSubtract:(int32_t)a b:(int32_t)b;
-
- /**
- * @return 2 to the power of a in GF(size)
- */
- - (int32_t)exp:(int)a;
-
- /**
- * @return base 2 log of a in GF(size)
- */
- - (int32_t)log:(int)a;
-
- /**
- * @return multiplicative inverse of a
- */
- - (int32_t)inverse:(int)a;
-
- /**
- * @return product of a and b in GF(size)
- */
- - (int32_t)multiply:(int)a b:(int)b;
-
- @end
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