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1 /******************************************************************************
2  *
3  * Copyright (C) 2015 The Android Open Source Project
4  *
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at:
8  *
9  * http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  *
17  *****************************************************************************
18  * Originally developed and contributed by Ittiam Systems Pvt. Ltd, Bangalore
19 */
20 /**
21 *******************************************************************************
22 * @file
23 *  ih264_trans_macros.h
24 *
25 * @brief
26 *  The file contains definitions of macros that perform forward and inverse
27 *  quantization
28 *
29 * @author
30 *  Ittiam
31 *
32 * @remark
33 *  None
34 *
35 *******************************************************************************
36 */
37 
38 #ifndef IH264_TRANS_MACROS_H_
39 #define IH264_TRANS_MACROS_H_
40 
41 /*****************************************************************************/
42 /* Function Macros                                                           */
43 /*****************************************************************************/
44 
45 /**
46 ******************************************************************************
47  *  @brief   Macro to perform forward quantization.
48  *  @description The value to be quantized is first compared with a threshold.
49  *  If the value is less than the threshold, the quantization value is returned
50  *  as zero else the value is quantized traditionally as per the rules of
51  *  h264 specification
52 ******************************************************************************
53  */
54 #define FWD_QUANT(i4_value, u4_abs_value, i4_sign, threshold, scale, rndfactor, qbits, u4_nnz)      \
55                 {\
56                         if (i4_value < 0)\
57                         {\
58                             u4_abs_value = -i4_value;\
59                             i4_sign = -1;\
60                         }\
61                         else\
62                         {\
63                             u4_abs_value = i4_value;\
64                             i4_sign = 1;\
65                         }\
66                         if (u4_abs_value < threshold)\
67                         {\
68                             i4_value = 0;\
69                         }\
70                         else\
71                         {\
72                             u4_abs_value *= scale;\
73                             u4_abs_value += rndfactor;\
74                             u4_abs_value >>= qbits;\
75                             i4_value = u4_abs_value * i4_sign;\
76                             if (i4_value)\
77                             {\
78                                 u4_nnz++;\
79                             }\
80                         }\
81                 }
82 
83 /**
84 ******************************************************************************
85  *  @brief   Macro to perform inverse quantization.
86  *  @remarks The value can also be de-quantized as
87  *  if (u4_qp_div_6 < 4)
88  *  {
89  *      i4_value = (quant_scale * weight_scale * i4_value + (1 << (3-u4_qp_div_6)))
90  *      i4_value >>= (4 - u4_qp_div_6)
91  *  }
92  *  else
93  *  {
94  *      i4_value = (quant_scale * weight_scale * i4_value) << (u4_qp_div_6 -4)
95  *  }
96 ******************************************************************************
97  */
98 #define INV_QUANT(i4_value, quant_scale, weight_scale, u4_qp_div_6, rndfactor, qbits)\
99                 {\
100                     i4_value *= quant_scale;\
101                     i4_value *= weight_scale;\
102                     i4_value += rndfactor;\
103                     i4_value <<= u4_qp_div_6;\
104                     i4_value >>= qbits;\
105                 }
106 
107 #define QUANT_H264(x,y,w,z,shft) (shft = ABS(x),\
108                 shft *= y,\
109                 shft += z,\
110                 shft = shft>>w,\
111                 shft = SIGNXY(shft,x))
112 
113 #define IQUANT_H264(x,y,wscal,w,shft) (shft = x, \
114                 shft *=y, \
115                 shft *=wscal, \
116                 shft = shft<<w)
117 
118 #define IQUANT_lev_H264(x,y,wscal,add_f,w,shft) (shft = x, \
119                 shft *=y, \
120                 shft *=wscal, \
121                 shft+= add_f, \
122                 shft = shft>>w)
123 
124 #endif /* IH264_TRANS_MACROS_H_ */
125