1 /*
2  * Copyright (C) 2008 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef bpi_FUNCTIONS_EM_H
18 #define bpi_FUNCTIONS_EM_H
19 
20 /**
21  * This files contains general purpose functions.
22  */
23 
24 /* ---- includes ----------------------------------------------------------- */
25 
26 #include "b_BasicEm/Basic.h"
27 #include "b_BasicEm/Context.h"
28 #include "b_BasicEm/Functions.h"
29 
30 /* ---- related objects  --------------------------------------------------- */
31 
32 /* ---- typedefs ----------------------------------------------------------- */
33 
34 
35 /** methods of similarty normalization for identification and verification */
36 enum bpi_SimType
37 {
38 	bpi_RAW_SIM,       /* take raw similarity only */
39 	bpi_SUB_MEAN,      /* subtract average  */
40 	bpi_SUB_MAX_1,     /* subtract maximum (different id of each entry) */
41 	bpi_SUB_MAX_2,     /* subtract maximum (different id of best entry) */
42 	bpi_SUB_4_MAX_2,   /* subtract average maximum of best 4 entries (method 2) */
43 	bpi_SUB_8_MAX_2,   /* subtract average maximum of best 8 entries (method 2) */
44 	bpi_SUB_16_MAX_2,  /* subtract average maximum of best 16 entries (method 2) */
45 	bpi_SUB_32_MAX_2   /* subtract average maximum of best 32 entries (method 2) */
46 };
47 
48 /* ---- constants ---------------------------------------------------------- */
49 
50 /* ---- external functions ------------------------------------------------- */
51 
52 /** Normalizes similarities.
53  *  This function is used by identifier module
54  */
55 void bpi_normalizeSimilarities( struct bbs_Context* cpA,
56 							    const int32* rawSimArrA,
57 							    const int32* rawIdArrA,
58 								uint32 rawSizeA,
59 								const int32* refSimArrA,
60 								const int32* refIdArrA,
61 								uint32 refSizeA,
62 								enum bpi_SimType simTypeA,
63 								int32* outSimArrA );
64 
65 /** Returnes normalized single similarity.
66  *  This function is used by verifier module
67  */
68 int32 bpi_normalizedSimilarity( struct bbs_Context* cpA,
69 							    int32 rawSimA,
70 							    int32 rawIdA,
71 								const int32* refSimArrA,
72 								const int32* refIdArrA,
73 								uint32 refSizeA,
74 								enum bpi_SimType simTypeA );
75 
76 
77 
78 /** writes checksum adjustment value to meet chkSumA to memory
79  *  the function assumes that memPtrA is memSizeA - 1 units
80  *  away from beginning of object-memory block
81  */
82 uint32 bpi_memWriteCsa16( uint16* memPtrA, uint32 memSizeA, uint16 chkSumA );
83 
84 /** takes checksum adjustment value from memory stream */
85 uint32 bpi_memReadCsa16( const uint16* memPtrA );
86 
87 /** tests check sum and produxes error condition if no match */
88 void bpi_testCheckSum( struct bbs_Context* cpA, uint16* memPtrA, uint16 chkSumA, const char* fNameA );
89 
90 
91 #endif /* bpi_FUNCTIONS_EM_H */
92 
93