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comparison filter_templates.h @ 403:b1e511c879d1

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More altcvt updates and fixes from Frank.
author Ryan C. Gordon <icculus@icculus.org>
date Sat, 13 Jul 2002 23:41:08 +0000
parents 44ed8bdeba74
children 45ee760a6f5a
comparison
equal deleted inserted replaced
402:7ced6c44b827 403:b1e511c879d1
33 /*-------------------------------------------------------------------------*/ 33 /*-------------------------------------------------------------------------*/
34 /* this filter (Kaiser-window beta=6.8) gives a decent -80dB attentuation */ 34 /* this filter (Kaiser-window beta=6.8) gives a decent -80dB attentuation */
35 /*-------------------------------------------------------------------------*/ 35 /*-------------------------------------------------------------------------*/
36 #define sum_d(v,dx) ((int) v[CH(dx)] + v[CH(1-dx)]) 36 #define sum_d(v,dx) ((int) v[CH(dx)] + v[CH(1-dx)])
37 static Sint16* Suffix(doubleRate)( Sint16 *outp, Sint16 *inp, int length, 37 static Sint16* Suffix(doubleRate)( Sint16 *outp, Sint16 *inp, int length,
38 VarFilter* filt, int* cpos ) 38 VarFilter* filt, RateAux* aux )
39 { 39 {
40 int out; 40 int out;
41 Sint16 *to; 41 Sint16 *to;
42 42
43 to = inp - length; 43 to = inp - length;
66 outp[CH(0)] = ( 32770 * inp[CH(0)] + out) >> 16; 66 outp[CH(0)] = ( 32770 * inp[CH(0)] + out) >> 16;
67 67
68 inp -= CH(1); 68 inp -= CH(1);
69 outp -= CH(2); 69 outp -= CH(2);
70 } 70 }
71
71 return outp; 72 return outp;
72 } 73 }
73 #undef sum_d 74 #undef sum_d
74 75
75 /*-------------------------------------------------------------------------*/ 76 /*-------------------------------------------------------------------------*/
76 #define sum_h(v,dx) ((int) v[CH(dx)] + v[CH(-dx)]) 77 #define sum_h(v,dx) ((int) v[CH(dx)] + v[CH(-dx)])
77 static Sint16* Suffix(halfRate)( Sint16 *outp, Sint16 *inp, int length, 78 static Sint16* Suffix(halfRate)( Sint16 *outp, Sint16 *inp, int length,
78 VarFilter* filt, int* cpos ) 79 VarFilter* filt, RateAux* aux )
79 { 80 {
80 int out; 81 int out;
81 Sint16* to; 82 Sint16* to;
82 83
83 to = inp + length; 84 to = inp + length;
85 inp += aux->carry;
84 86
85 while( inp < to ) 87 while( inp < to )
86 { 88 {
87 out = 0; 89 out = 0;
88 out-= 9 * sum_h( inp, 31); 90 out-= 9 * sum_h( inp, 31);
103 out+= 20798 * sum_h( inp, 1); 105 out+= 20798 * sum_h( inp, 1);
104 out+= 32770 * (int)inp[0]; 106 out+= 32770 * (int)inp[0];
105 107
106 outp[0] = out >> 16; 108 outp[0] = out >> 16;
107 109
108 inp+= CH(2); 110 inp += CH(2);
109 outp += CH(1); 111 outp += CH(1);
110 } 112 }
113
114 aux->carry = inp < to + CH(1) ? 0 : CH(1);
111 return outp; 115 return outp;
112 } 116 }
113 #undef sum_h 117 #undef sum_h
114 118
115 /*-------------------------------------------------------------------------*/ 119 /*-------------------------------------------------------------------------*/
116 static Sint16* Suffix(increaseRate)( Sint16 *outp, Sint16 *inp, int length, 120 static Sint16* Suffix(increaseRate)( Sint16 *outp, Sint16 *inp, int length,
117 VarFilter* filter, int* cpos ) 121 VarFilter* filter, RateAux* aux )
118 { 122 {
119 const static int fsize = CH(2*_fsize); 123 const static int fsize = CH(2*_fsize);
120 Sint16 *f; 124 Sint16 *f;
121 int out; 125 int out;
122 int i, pos; 126 int i, pos;
123 Sint16* to; 127 Sint16* to;
124 128
125 inp -= fsize; 129 inp -= fsize;
126 to = inp - length; 130 to = inp - length;
127 pos = *cpos; 131 pos = aux->pos;
128 132
129 while( inp > to ) 133 while( inp > to )
130 { 134 {
131 out = 0; 135 out = 0;
132 f = filter->c[pos]; 136 f = filter->c[pos];
144 inp -= CH( 4 * _fsize ); 148 inp -= CH( 4 * _fsize );
145 inp -= CH( filter->incr[pos] ); 149 inp -= CH( filter->incr[pos] );
146 outp -= CH(1); 150 outp -= CH(1);
147 } 151 }
148 152
149 *cpos = pos; 153 aux->pos = pos;
150 return outp; 154 return outp;
151 } 155 }
152 156
153 /*-------------------------------------------------------------------------*/ 157 /*-------------------------------------------------------------------------*/
154 static Sint16* Suffix(decreaseRate)( Sint16 *outp, Sint16 *inp, int length, 158 static Sint16* Suffix(decreaseRate)( Sint16 *outp, Sint16 *inp, int length,
155 VarFilter* filter, int* cpos ) 159 VarFilter* filter, RateAux* aux )
156 { 160 {
157 const static int fsize = CH(2*_fsize); 161 const static int fsize = CH(2*_fsize);
158 Sint16 *f; 162 Sint16 *f;
159 int out; 163 int out;
160 int i, pos; 164 int i, pos;
161 Sint16 *to; 165 Sint16 *to;
162 166
163 inp -= fsize; 167 inp -= fsize;
164 to = inp + length; 168 to = inp + length;
165 pos = *cpos; 169 pos = aux->pos;
170 inp += aux->carry;
166 171
167 while( inp < to ) 172 while( inp < to )
168 { 173 {
169 out = 0; 174 out = 0;
170 f = filter->c[pos]; 175 f = filter->c[pos];
181 inp += CH( filter->incr[pos] ); 186 inp += CH( filter->incr[pos] );
182 outp += CH(1); 187 outp += CH(1);
183 pos = ( pos + 1 ) % filter->ratio.denominator; 188 pos = ( pos + 1 ) % filter->ratio.denominator;
184 } 189 }
185 190
186 *cpos = pos; 191 aux->pos = pos;
192 aux->carry = inp < to + CH(1) ? 0 : CH(1);
187 return outp; 193 return outp;
188 } 194 }
189 195
190 /*-------------------------------------------------------------------------*/ 196 /*-------------------------------------------------------------------------*/
191 #undef CH 197 #undef CH