FFmpeg
faandct.c
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1 /*
2  * Floating point AAN DCT
3  * this implementation is based upon the IJG integer AAN DCT (see jfdctfst.c)
4  *
5  * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
6  * Copyright (c) 2003 Roman Shaposhnik
7  *
8  * Permission to use, copy, modify, and/or distribute this software for any
9  * purpose with or without fee is hereby granted, provided that the above
10  * copyright notice and this permission notice appear in all copies.
11  *
12  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
13  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
14  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
15  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
16  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
17  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
18  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19  */
20 
21 /**
22  * @file
23  * @brief
24  * Floating point AAN DCT
25  * @author Michael Niedermayer <michaelni@gmx.at>
26  */
27 
28 #include "faandct.h"
29 #include "libavutil/internal.h"
30 #include "libavutil/libm.h"
31 
32 typedef float FLOAT;
33 
34 /* numbers generated by arbitrary precision arithmetic followed by truncation
35 to 36 fractional digits (enough for a 128-bit IEEE quad, see /usr/include/math.h
36 for this approach). Unfortunately, long double is not always available correctly,
37 e.g ppc has issues.
38 TODO: add L suffixes when ppc and toolchains sort out their stuff.
39 */
40 #define B0 1.000000000000000000000000000000000000
41 #define B1 0.720959822006947913789091890943021267 // (cos(pi*1/16)sqrt(2))^-1
42 #define B2 0.765366864730179543456919968060797734 // (cos(pi*2/16)sqrt(2))^-1
43 #define B3 0.850430094767256448766702844371412325 // (cos(pi*3/16)sqrt(2))^-1
44 #define B4 1.000000000000000000000000000000000000 // (cos(pi*4/16)sqrt(2))^-1
45 #define B5 1.272758580572833938461007018281767032 // (cos(pi*5/16)sqrt(2))^-1
46 #define B6 1.847759065022573512256366378793576574 // (cos(pi*6/16)sqrt(2))^-1
47 #define B7 3.624509785411551372409941227504289587 // (cos(pi*7/16)sqrt(2))^-1
48 
49 #define A1 M_SQRT1_2 // cos(pi*4/16)
50 #define A2 0.54119610014619698435 // cos(pi*6/16)sqrt(2)
51 #define A5 0.38268343236508977170 // cos(pi*6/16)
52 #define A4 1.30656296487637652774 // cos(pi*2/16)sqrt(2)
53 
54 static const FLOAT postscale[64]={
55 B0*B0, B0*B1, B0*B2, B0*B3, B0*B4, B0*B5, B0*B6, B0*B7,
56 B1*B0, B1*B1, B1*B2, B1*B3, B1*B4, B1*B5, B1*B6, B1*B7,
57 B2*B0, B2*B1, B2*B2, B2*B3, B2*B4, B2*B5, B2*B6, B2*B7,
58 B3*B0, B3*B1, B3*B2, B3*B3, B3*B4, B3*B5, B3*B6, B3*B7,
59 B4*B0, B4*B1, B4*B2, B4*B3, B4*B4, B4*B5, B4*B6, B4*B7,
60 B5*B0, B5*B1, B5*B2, B5*B3, B5*B4, B5*B5, B5*B6, B5*B7,
61 B6*B0, B6*B1, B6*B2, B6*B3, B6*B4, B6*B5, B6*B6, B6*B7,
62 B7*B0, B7*B1, B7*B2, B7*B3, B7*B4, B7*B5, B7*B6, B7*B7,
63 };
64 
65 static av_always_inline void row_fdct(FLOAT temp[64], int16_t *data)
66 {
67  FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
68  FLOAT tmp10, tmp11, tmp12, tmp13;
69  FLOAT z2, z4, z11, z13;
70  int i;
71 
72  for (i=0; i<8*8; i+=8) {
73  tmp0= data[0 + i] + data[7 + i];
74  tmp7= data[0 + i] - data[7 + i];
75  tmp1= data[1 + i] + data[6 + i];
76  tmp6= data[1 + i] - data[6 + i];
77  tmp2= data[2 + i] + data[5 + i];
78  tmp5= data[2 + i] - data[5 + i];
79  tmp3= data[3 + i] + data[4 + i];
80  tmp4= data[3 + i] - data[4 + i];
81 
82  tmp10= tmp0 + tmp3;
83  tmp13= tmp0 - tmp3;
84  tmp11= tmp1 + tmp2;
85  tmp12= tmp1 - tmp2;
86 
87  temp[0 + i]= tmp10 + tmp11;
88  temp[4 + i]= tmp10 - tmp11;
89 
90  tmp12 += tmp13;
91  tmp12 *= A1;
92  temp[2 + i]= tmp13 + tmp12;
93  temp[6 + i]= tmp13 - tmp12;
94 
95  tmp4 += tmp5;
96  tmp5 += tmp6;
97  tmp6 += tmp7;
98 
99  z2= tmp4*(A2+A5) - tmp6*A5;
100  z4= tmp6*(A4-A5) + tmp4*A5;
101 
102  tmp5*=A1;
103 
104  z11= tmp7 + tmp5;
105  z13= tmp7 - tmp5;
106 
107  temp[5 + i]= z13 + z2;
108  temp[3 + i]= z13 - z2;
109  temp[1 + i]= z11 + z4;
110  temp[7 + i]= z11 - z4;
111  }
112 }
113 
114 void ff_faandct(int16_t *data)
115 {
116  FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
117  FLOAT tmp10, tmp11, tmp12, tmp13;
118  FLOAT z2, z4, z11, z13;
119  FLOAT temp[64];
120  int i;
121 
122  emms_c();
123 
124  row_fdct(temp, data);
125 
126  for (i=0; i<8; i++) {
127  tmp0= temp[8*0 + i] + temp[8*7 + i];
128  tmp7= temp[8*0 + i] - temp[8*7 + i];
129  tmp1= temp[8*1 + i] + temp[8*6 + i];
130  tmp6= temp[8*1 + i] - temp[8*6 + i];
131  tmp2= temp[8*2 + i] + temp[8*5 + i];
132  tmp5= temp[8*2 + i] - temp[8*5 + i];
133  tmp3= temp[8*3 + i] + temp[8*4 + i];
134  tmp4= temp[8*3 + i] - temp[8*4 + i];
135 
136  tmp10= tmp0 + tmp3;
137  tmp13= tmp0 - tmp3;
138  tmp11= tmp1 + tmp2;
139  tmp12= tmp1 - tmp2;
140 
141  data[8*0 + i]= lrintf(postscale[8*0 + i] * (tmp10 + tmp11));
142  data[8*4 + i]= lrintf(postscale[8*4 + i] * (tmp10 - tmp11));
143 
144  tmp12 += tmp13;
145  tmp12 *= A1;
146  data[8*2 + i]= lrintf(postscale[8*2 + i] * (tmp13 + tmp12));
147  data[8*6 + i]= lrintf(postscale[8*6 + i] * (tmp13 - tmp12));
148 
149  tmp4 += tmp5;
150  tmp5 += tmp6;
151  tmp6 += tmp7;
152 
153  z2= tmp4*(A2+A5) - tmp6*A5;
154  z4= tmp6*(A4-A5) + tmp4*A5;
155 
156  tmp5*=A1;
157 
158  z11= tmp7 + tmp5;
159  z13= tmp7 - tmp5;
160 
161  data[8*5 + i]= lrintf(postscale[8*5 + i] * (z13 + z2));
162  data[8*3 + i]= lrintf(postscale[8*3 + i] * (z13 - z2));
163  data[8*1 + i]= lrintf(postscale[8*1 + i] * (z11 + z4));
164  data[8*7 + i]= lrintf(postscale[8*7 + i] * (z11 - z4));
165  }
166 }
167 
168 void ff_faandct248(int16_t *data)
169 {
170  FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
171  FLOAT tmp10, tmp11, tmp12, tmp13;
172  FLOAT temp[64];
173  int i;
174 
175  emms_c();
176 
177  row_fdct(temp, data);
178 
179  for (i=0; i<8; i++) {
180  tmp0 = temp[8*0 + i] + temp[8*1 + i];
181  tmp1 = temp[8*2 + i] + temp[8*3 + i];
182  tmp2 = temp[8*4 + i] + temp[8*5 + i];
183  tmp3 = temp[8*6 + i] + temp[8*7 + i];
184  tmp4 = temp[8*0 + i] - temp[8*1 + i];
185  tmp5 = temp[8*2 + i] - temp[8*3 + i];
186  tmp6 = temp[8*4 + i] - temp[8*5 + i];
187  tmp7 = temp[8*6 + i] - temp[8*7 + i];
188 
189  tmp10 = tmp0 + tmp3;
190  tmp11 = tmp1 + tmp2;
191  tmp12 = tmp1 - tmp2;
192  tmp13 = tmp0 - tmp3;
193 
194  data[8*0 + i] = lrintf(postscale[8*0 + i] * (tmp10 + tmp11));
195  data[8*4 + i] = lrintf(postscale[8*4 + i] * (tmp10 - tmp11));
196 
197  tmp12 += tmp13;
198  tmp12 *= A1;
199  data[8*2 + i] = lrintf(postscale[8*2 + i] * (tmp13 + tmp12));
200  data[8*6 + i] = lrintf(postscale[8*6 + i] * (tmp13 - tmp12));
201 
202  tmp10 = tmp4 + tmp7;
203  tmp11 = tmp5 + tmp6;
204  tmp12 = tmp5 - tmp6;
205  tmp13 = tmp4 - tmp7;
206 
207  data[8*1 + i] = lrintf(postscale[8*0 + i] * (tmp10 + tmp11));
208  data[8*5 + i] = lrintf(postscale[8*4 + i] * (tmp10 - tmp11));
209 
210  tmp12 += tmp13;
211  tmp12 *= A1;
212  data[8*3 + i] = lrintf(postscale[8*2 + i] * (tmp13 + tmp12));
213  data[8*7 + i] = lrintf(postscale[8*6 + i] * (tmp13 - tmp12));
214  }
215 }
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
else temp
Definition: vf_mcdeint.c:256
void ff_faandct248(int16_t *data)
Definition: faandct.c:168
#define B7
Definition: faandct.c:47
#define B1
Definition: faandct.c:41
#define B4
Definition: faandct.c:44
#define lrintf(x)
Definition: libm_mips.h:70
#define B2
Definition: faandct.c:42
#define A4
Definition: faandct.c:52
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
static const FLOAT postscale[64]
Definition: faandct.c:54
#define B5
Definition: faandct.c:45
common internal API header
float FLOAT
Definition: faandct.c:32
void ff_faandct(int16_t *data)
Definition: faandct.c:114
#define B6
Definition: faandct.c:46
Replacements for frequently missing libm functions.
static av_always_inline void row_fdct(FLOAT temp[64], int16_t *data)
Definition: faandct.c:65
#define A2
Definition: faandct.c:50
#define A5
Definition: faandct.c:51
#define B3
Definition: faandct.c:43
#define av_always_inline
Definition: attributes.h:39
Floating point AAN DCT
#define A1
Definition: faandct.c:49
#define B0
Definition: faandct.c:40