/*
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* Copyright 2012 ZXing authors
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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@class ZXGenericGF, ZXIntArray;
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/**
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* Implements Reed-Solomon decoding, as the name implies.
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*
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* The algorithm will not be explained here, but the following references were helpful
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* in creating this implementation:
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*
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* Bruce Maggs.
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* http://www.cs.cmu.edu/afs/cs.cmu.edu/project/pscico-guyb/realworld/www/rs_decode.ps
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* "Decoding Reed-Solomon Codes" (see discussion of Forney's Formula)
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*
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* J.I. Hall. www.mth.msu.edu/~jhall/classes/codenotes/GRS.pdf
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* "Chapter 5. Generalized Reed-Solomon Codes"
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* (see discussion of Euclidean algorithm)
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*
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* Much credit is due to William Rucklidge since portions of this code are an indirect
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* port of his C++ Reed-Solomon implementation.
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*/
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@interface ZXReedSolomonDecoder : NSObject
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- (id)initWithField:(ZXGenericGF *)field;
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/**
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* Decodes given set of received codewords, which include both data and error-correction
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* codewords. Really, this means it uses Reed-Solomon to detect and correct errors, in-place,
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* in the input.
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*
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* @param received data and error-correction codewords
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* @param twoS number of error-correction codewords available
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* @return NO if decoding fails for any reason
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*/
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- (BOOL)decode:(ZXIntArray *)received twoS:(int)twoS error:(NSError **)error;
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@end
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