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Diffstat (limited to 'ml/dlib/dlib/entropy_decoder/entropy_decoder_kernel_abstract.h')
| -rw-r--r-- | ml/dlib/dlib/entropy_decoder/entropy_decoder_kernel_abstract.h | 207 |
1 files changed, 0 insertions, 207 deletions
diff --git a/ml/dlib/dlib/entropy_decoder/entropy_decoder_kernel_abstract.h b/ml/dlib/dlib/entropy_decoder/entropy_decoder_kernel_abstract.h deleted file mode 100644 index 89906b9ae..000000000 --- a/ml/dlib/dlib/entropy_decoder/entropy_decoder_kernel_abstract.h +++ /dev/null @@ -1,207 +0,0 @@ -// Copyright (C) 2003 Davis E. King (davis@dlib.net) -// License: Boost Software License See LICENSE.txt for the full license. -#undef DLIB_ENTROPY_DECODER_KERNEl_ABSTRACT_ -#ifdef DLIB_ENTROPY_DECODER_KERNEl_ABSTRACT_ - -#include "../algs.h" -#include <iosfwd> -#include "../uintn.h" - -namespace dlib -{ - - class entropy_decoder - { - /*! - INITIAL VALUE - stream_is_set() == false - get_target_called() == false - - - WHAT THIS OBJECT REPRESENTS - This object represents an entropy decoder (could be implemented as an - arithmetic decoder for example). - - Note that all implementations of entropy_encoder and entropy_decoder - are paired. This means that if you use entropy_encoder_kernel_n to - encode something then you must use the corresponding - entropy_decoder_kernel_n to decode it. - - - WHERE IS EOF? - It is important to note that this object will not give any indication - that is has hit the end of the input stream when it occurs. It is - up to you to use some kind of coding scheme to detect this in the - compressed data stream. - - Another important thing to know is that decode() must be called - exactly the same number of times as encode() and with the same values - supplied for TOTAL, high_count, and low_count. Doing this ensures - that the decoder consumes exactly all the bytes from the input - stream that were written by the entropy_encoder. - - NOTATION: - At any moment each symbol has a certain probability of appearing in - the input stream. These probabilities may change as each symbol is - decoded and the probability model is updated accordingly. - - - - Before considering current symbol: - - let P(i) be a function which gives the probability of seeing the ith - symbol of an N symbol alphabet. Note that P(i) refers to the probability - of seeing the ith symbol WITHOUT considering the symbol currently given - by get_target(TOTAL). ( The domain of P(i) is from 0 to N-1. ) - - for each i: P(i) == COUNT/TOTAL where COUNT and TOTAL are integers - and TOTAL is the same number for all P(i) but COUNT may vary. - - let LOW_COUNT(i) be the sum of all P(x)*TOTAL from x == 0 to x == i-1 - (note that LOW_COUNT(0) == 0) - let HIGH_COUNT(i) be the sum of all P(x)*TOTAL from x == 0 to x == i - - - - After considering current symbol: - - let #P(i) be a function which gives the probability of seeing the ith - symbol after we have updated our probability model to take the symbol - given by get_target(TOTAL) into account. - - for each i: #P(i) == #COUNT/#TOTAL where #COUNT and #TOTAL are integers - and #TOTAL is the same number for all #P(i) but #COUNT may vary. - !*/ - - public: - - entropy_decoder ( - ); - /*! - ensures - - #*this is properly initialized - throws - - std::bad_alloc - !*/ - - virtual ~entropy_decoder ( - ); - /*! - ensures - - all memory associated with *this has been released - !*/ - - void clear( - ); - /*! - ensures - - #*this has its initial value - - if (stream_is_set()) - - clears any state accumulated in *this from decoding data from - the stream get_stream() - throws - - any exception - if this exception is thrown then #*this is unusable - until clear() is called and succeeds - !*/ - - void set_stream ( - std::istream& in - ); - /*! - ensures - - #*this will read data from in and decode it - - #stream_is_set() == true - - #get_target() == a number representing the first symbol from in - - #get_target_called() == false - - if (stream_is_set()) - - clears any state accumulated in *this from decoding data from - the stream get_stream() - throws - - any exception - if this exception is thrown then #*this is unusable - until clear() is called and succeeds - !*/ - - bool stream_is_set ( - ) const; - /*! - ensures - - returns true if a stream has been associated with *this by calling - set_stream() - !*/ - - std::istream& get_stream ( - ) const; - /*! - requires - - stream_is_set() == true - ensures - - returns a reference to the istream object that *this is reading - encoded data from - !*/ - - - void decode ( - uint32 low_count, - uint32 high_count - ); - /*! - requires - - get_target_called() == true - - stream_is_set() == true - - low_count == LOW_COUNT(S) where S is the symbol represented - by get_target(TOTAL) - - high_count == HIGH_COUNT(S) where S is the symbol represented - by get_target(TOTAL) - - low_count <= get_target(TOTAL) < high_count <= TOTAL - ensures - - #get_target(#TOTAL) == a number which represents the next symbol - - #get_target_called() == false - throws - - any exception - if this exception is thrown then #*this is unusable - until clear() is called and succeeds - !*/ - - bool get_target_called ( - ) const; - /*! - ensures - - returns true if get_target() has been called and since then decode() - and set_stream() have not been called - - returns false otherwise - !*/ - - uint32 get_target ( - uint32 total - ); - /*! - requires - - 0 < total < 65536 (2^16) - - total == TOTAL - - stream_is_set() == true - ensures - - in the next call to decode() the value of TOTAL will be - considered to be total - - #get_target_called() == true - - returns a number N such that: - - N is in the range 0 to total - 1 - - N represents a symbol S where - LOW_COUNT(S) <= N < HIGH_COUNT(S) - throws - - any exception - if this exception is thrown then #*this is unusable - until clear() is called and succeeds - !*/ - - private: - - // restricted functions - entropy_decoder(entropy_decoder&); // copy constructor - entropy_decoder& operator=(entropy_decoder&); // assignment operator - - }; - -} - -#endif // DLIB_ENTROPY_DECODER_KERNEl_ABSTRACT_ - |