diff options
Diffstat (limited to 'libraries/irrlicht-1.8/source/Irrlicht/jpeglib/jfdctflt.c')
-rw-r--r-- | libraries/irrlicht-1.8/source/Irrlicht/jpeglib/jfdctflt.c | 348 |
1 files changed, 174 insertions, 174 deletions
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/jfdctflt.c b/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/jfdctflt.c index 3c1b174..74d0d86 100644 --- a/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/jfdctflt.c +++ b/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/jfdctflt.c | |||
@@ -1,174 +1,174 @@ | |||
1 | /* | 1 | /* |
2 | * jfdctflt.c | 2 | * jfdctflt.c |
3 | * | 3 | * |
4 | * Copyright (C) 1994-1996, Thomas G. Lane. | 4 | * Copyright (C) 1994-1996, Thomas G. Lane. |
5 | * Modified 2003-2009 by Guido Vollbeding. | 5 | * Modified 2003-2009 by Guido Vollbeding. |
6 | * This file is part of the Independent JPEG Group's software. | 6 | * This file is part of the Independent JPEG Group's software. |
7 | * For conditions of distribution and use, see the accompanying README file. | 7 | * For conditions of distribution and use, see the accompanying README file. |
8 | * | 8 | * |
9 | * This file contains a floating-point implementation of the | 9 | * This file contains a floating-point implementation of the |
10 | * forward DCT (Discrete Cosine Transform). | 10 | * forward DCT (Discrete Cosine Transform). |
11 | * | 11 | * |
12 | * This implementation should be more accurate than either of the integer | 12 | * This implementation should be more accurate than either of the integer |
13 | * DCT implementations. However, it may not give the same results on all | 13 | * DCT implementations. However, it may not give the same results on all |
14 | * machines because of differences in roundoff behavior. Speed will depend | 14 | * machines because of differences in roundoff behavior. Speed will depend |
15 | * on the hardware's floating point capacity. | 15 | * on the hardware's floating point capacity. |
16 | * | 16 | * |
17 | * A 2-D DCT can be done by 1-D DCT on each row followed by 1-D DCT | 17 | * A 2-D DCT can be done by 1-D DCT on each row followed by 1-D DCT |
18 | * on each column. Direct algorithms are also available, but they are | 18 | * on each column. Direct algorithms are also available, but they are |
19 | * much more complex and seem not to be any faster when reduced to code. | 19 | * much more complex and seem not to be any faster when reduced to code. |
20 | * | 20 | * |
21 | * This implementation is based on Arai, Agui, and Nakajima's algorithm for | 21 | * This implementation is based on Arai, Agui, and Nakajima's algorithm for |
22 | * scaled DCT. Their original paper (Trans. IEICE E-71(11):1095) is in | 22 | * scaled DCT. Their original paper (Trans. IEICE E-71(11):1095) is in |
23 | * Japanese, but the algorithm is described in the Pennebaker & Mitchell | 23 | * Japanese, but the algorithm is described in the Pennebaker & Mitchell |
24 | * JPEG textbook (see REFERENCES section in file README). The following code | 24 | * JPEG textbook (see REFERENCES section in file README). The following code |
25 | * is based directly on figure 4-8 in P&M. | 25 | * is based directly on figure 4-8 in P&M. |
26 | * While an 8-point DCT cannot be done in less than 11 multiplies, it is | 26 | * While an 8-point DCT cannot be done in less than 11 multiplies, it is |
27 | * possible to arrange the computation so that many of the multiplies are | 27 | * possible to arrange the computation so that many of the multiplies are |
28 | * simple scalings of the final outputs. These multiplies can then be | 28 | * simple scalings of the final outputs. These multiplies can then be |
29 | * folded into the multiplications or divisions by the JPEG quantization | 29 | * folded into the multiplications or divisions by the JPEG quantization |
30 | * table entries. The AA&N method leaves only 5 multiplies and 29 adds | 30 | * table entries. The AA&N method leaves only 5 multiplies and 29 adds |
31 | * to be done in the DCT itself. | 31 | * to be done in the DCT itself. |
32 | * The primary disadvantage of this method is that with a fixed-point | 32 | * The primary disadvantage of this method is that with a fixed-point |
33 | * implementation, accuracy is lost due to imprecise representation of the | 33 | * implementation, accuracy is lost due to imprecise representation of the |
34 | * scaled quantization values. However, that problem does not arise if | 34 | * scaled quantization values. However, that problem does not arise if |
35 | * we use floating point arithmetic. | 35 | * we use floating point arithmetic. |
36 | */ | 36 | */ |
37 | 37 | ||
38 | #define JPEG_INTERNALS | 38 | #define JPEG_INTERNALS |
39 | #include "jinclude.h" | 39 | #include "jinclude.h" |
40 | #include "jpeglib.h" | 40 | #include "jpeglib.h" |
41 | #include "jdct.h" /* Private declarations for DCT subsystem */ | 41 | #include "jdct.h" /* Private declarations for DCT subsystem */ |
42 | 42 | ||
43 | #ifdef DCT_FLOAT_SUPPORTED | 43 | #ifdef DCT_FLOAT_SUPPORTED |
44 | 44 | ||
45 | 45 | ||
46 | /* | 46 | /* |
47 | * This module is specialized to the case DCTSIZE = 8. | 47 | * This module is specialized to the case DCTSIZE = 8. |
48 | */ | 48 | */ |
49 | 49 | ||
50 | #if DCTSIZE != 8 | 50 | #if DCTSIZE != 8 |
51 | Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */ | 51 | Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */ |
52 | #endif | 52 | #endif |
53 | 53 | ||
54 | 54 | ||
55 | /* | 55 | /* |
56 | * Perform the forward DCT on one block of samples. | 56 | * Perform the forward DCT on one block of samples. |
57 | */ | 57 | */ |
58 | 58 | ||
59 | GLOBAL(void) | 59 | GLOBAL(void) |
60 | jpeg_fdct_float (FAST_FLOAT * data, JSAMPARRAY sample_data, JDIMENSION start_col) | 60 | jpeg_fdct_float (FAST_FLOAT * data, JSAMPARRAY sample_data, JDIMENSION start_col) |
61 | { | 61 | { |
62 | FAST_FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7; | 62 | FAST_FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7; |
63 | FAST_FLOAT tmp10, tmp11, tmp12, tmp13; | 63 | FAST_FLOAT tmp10, tmp11, tmp12, tmp13; |
64 | FAST_FLOAT z1, z2, z3, z4, z5, z11, z13; | 64 | FAST_FLOAT z1, z2, z3, z4, z5, z11, z13; |
65 | FAST_FLOAT *dataptr; | 65 | FAST_FLOAT *dataptr; |
66 | JSAMPROW elemptr; | 66 | JSAMPROW elemptr; |
67 | int ctr; | 67 | int ctr; |
68 | 68 | ||
69 | /* Pass 1: process rows. */ | 69 | /* Pass 1: process rows. */ |
70 | 70 | ||
71 | dataptr = data; | 71 | dataptr = data; |
72 | for (ctr = 0; ctr < DCTSIZE; ctr++) { | 72 | for (ctr = 0; ctr < DCTSIZE; ctr++) { |
73 | elemptr = sample_data[ctr] + start_col; | 73 | elemptr = sample_data[ctr] + start_col; |
74 | 74 | ||
75 | /* Load data into workspace */ | 75 | /* Load data into workspace */ |
76 | tmp0 = (FAST_FLOAT) (GETJSAMPLE(elemptr[0]) + GETJSAMPLE(elemptr[7])); | 76 | tmp0 = (FAST_FLOAT) (GETJSAMPLE(elemptr[0]) + GETJSAMPLE(elemptr[7])); |
77 | tmp7 = (FAST_FLOAT) (GETJSAMPLE(elemptr[0]) - GETJSAMPLE(elemptr[7])); | 77 | tmp7 = (FAST_FLOAT) (GETJSAMPLE(elemptr[0]) - GETJSAMPLE(elemptr[7])); |
78 | tmp1 = (FAST_FLOAT) (GETJSAMPLE(elemptr[1]) + GETJSAMPLE(elemptr[6])); | 78 | tmp1 = (FAST_FLOAT) (GETJSAMPLE(elemptr[1]) + GETJSAMPLE(elemptr[6])); |
79 | tmp6 = (FAST_FLOAT) (GETJSAMPLE(elemptr[1]) - GETJSAMPLE(elemptr[6])); | 79 | tmp6 = (FAST_FLOAT) (GETJSAMPLE(elemptr[1]) - GETJSAMPLE(elemptr[6])); |
80 | tmp2 = (FAST_FLOAT) (GETJSAMPLE(elemptr[2]) + GETJSAMPLE(elemptr[5])); | 80 | tmp2 = (FAST_FLOAT) (GETJSAMPLE(elemptr[2]) + GETJSAMPLE(elemptr[5])); |
81 | tmp5 = (FAST_FLOAT) (GETJSAMPLE(elemptr[2]) - GETJSAMPLE(elemptr[5])); | 81 | tmp5 = (FAST_FLOAT) (GETJSAMPLE(elemptr[2]) - GETJSAMPLE(elemptr[5])); |
82 | tmp3 = (FAST_FLOAT) (GETJSAMPLE(elemptr[3]) + GETJSAMPLE(elemptr[4])); | 82 | tmp3 = (FAST_FLOAT) (GETJSAMPLE(elemptr[3]) + GETJSAMPLE(elemptr[4])); |
83 | tmp4 = (FAST_FLOAT) (GETJSAMPLE(elemptr[3]) - GETJSAMPLE(elemptr[4])); | 83 | tmp4 = (FAST_FLOAT) (GETJSAMPLE(elemptr[3]) - GETJSAMPLE(elemptr[4])); |
84 | 84 | ||
85 | /* Even part */ | 85 | /* Even part */ |
86 | 86 | ||
87 | tmp10 = tmp0 + tmp3; /* phase 2 */ | 87 | tmp10 = tmp0 + tmp3; /* phase 2 */ |
88 | tmp13 = tmp0 - tmp3; | 88 | tmp13 = tmp0 - tmp3; |
89 | tmp11 = tmp1 + tmp2; | 89 | tmp11 = tmp1 + tmp2; |
90 | tmp12 = tmp1 - tmp2; | 90 | tmp12 = tmp1 - tmp2; |
91 | 91 | ||
92 | /* Apply unsigned->signed conversion */ | 92 | /* Apply unsigned->signed conversion */ |
93 | dataptr[0] = tmp10 + tmp11 - 8 * CENTERJSAMPLE; /* phase 3 */ | 93 | dataptr[0] = tmp10 + tmp11 - 8 * CENTERJSAMPLE; /* phase 3 */ |
94 | dataptr[4] = tmp10 - tmp11; | 94 | dataptr[4] = tmp10 - tmp11; |
95 | 95 | ||
96 | z1 = (tmp12 + tmp13) * ((FAST_FLOAT) 0.707106781); /* c4 */ | 96 | z1 = (tmp12 + tmp13) * ((FAST_FLOAT) 0.707106781); /* c4 */ |
97 | dataptr[2] = tmp13 + z1; /* phase 5 */ | 97 | dataptr[2] = tmp13 + z1; /* phase 5 */ |
98 | dataptr[6] = tmp13 - z1; | 98 | dataptr[6] = tmp13 - z1; |
99 | 99 | ||
100 | /* Odd part */ | 100 | /* Odd part */ |
101 | 101 | ||
102 | tmp10 = tmp4 + tmp5; /* phase 2 */ | 102 | tmp10 = tmp4 + tmp5; /* phase 2 */ |
103 | tmp11 = tmp5 + tmp6; | 103 | tmp11 = tmp5 + tmp6; |
104 | tmp12 = tmp6 + tmp7; | 104 | tmp12 = tmp6 + tmp7; |
105 | 105 | ||
106 | /* The rotator is modified from fig 4-8 to avoid extra negations. */ | 106 | /* The rotator is modified from fig 4-8 to avoid extra negations. */ |
107 | z5 = (tmp10 - tmp12) * ((FAST_FLOAT) 0.382683433); /* c6 */ | 107 | z5 = (tmp10 - tmp12) * ((FAST_FLOAT) 0.382683433); /* c6 */ |
108 | z2 = ((FAST_FLOAT) 0.541196100) * tmp10 + z5; /* c2-c6 */ | 108 | z2 = ((FAST_FLOAT) 0.541196100) * tmp10 + z5; /* c2-c6 */ |
109 | z4 = ((FAST_FLOAT) 1.306562965) * tmp12 + z5; /* c2+c6 */ | 109 | z4 = ((FAST_FLOAT) 1.306562965) * tmp12 + z5; /* c2+c6 */ |
110 | z3 = tmp11 * ((FAST_FLOAT) 0.707106781); /* c4 */ | 110 | z3 = tmp11 * ((FAST_FLOAT) 0.707106781); /* c4 */ |
111 | 111 | ||
112 | z11 = tmp7 + z3; /* phase 5 */ | 112 | z11 = tmp7 + z3; /* phase 5 */ |
113 | z13 = tmp7 - z3; | 113 | z13 = tmp7 - z3; |
114 | 114 | ||
115 | dataptr[5] = z13 + z2; /* phase 6 */ | 115 | dataptr[5] = z13 + z2; /* phase 6 */ |
116 | dataptr[3] = z13 - z2; | 116 | dataptr[3] = z13 - z2; |
117 | dataptr[1] = z11 + z4; | 117 | dataptr[1] = z11 + z4; |
118 | dataptr[7] = z11 - z4; | 118 | dataptr[7] = z11 - z4; |
119 | 119 | ||
120 | dataptr += DCTSIZE; /* advance pointer to next row */ | 120 | dataptr += DCTSIZE; /* advance pointer to next row */ |
121 | } | 121 | } |
122 | 122 | ||
123 | /* Pass 2: process columns. */ | 123 | /* Pass 2: process columns. */ |
124 | 124 | ||
125 | dataptr = data; | 125 | dataptr = data; |
126 | for (ctr = DCTSIZE-1; ctr >= 0; ctr--) { | 126 | for (ctr = DCTSIZE-1; ctr >= 0; ctr--) { |
127 | tmp0 = dataptr[DCTSIZE*0] + dataptr[DCTSIZE*7]; | 127 | tmp0 = dataptr[DCTSIZE*0] + dataptr[DCTSIZE*7]; |
128 | tmp7 = dataptr[DCTSIZE*0] - dataptr[DCTSIZE*7]; | 128 | tmp7 = dataptr[DCTSIZE*0] - dataptr[DCTSIZE*7]; |
129 | tmp1 = dataptr[DCTSIZE*1] + dataptr[DCTSIZE*6]; | 129 | tmp1 = dataptr[DCTSIZE*1] + dataptr[DCTSIZE*6]; |
130 | tmp6 = dataptr[DCTSIZE*1] - dataptr[DCTSIZE*6]; | 130 | tmp6 = dataptr[DCTSIZE*1] - dataptr[DCTSIZE*6]; |
131 | tmp2 = dataptr[DCTSIZE*2] + dataptr[DCTSIZE*5]; | 131 | tmp2 = dataptr[DCTSIZE*2] + dataptr[DCTSIZE*5]; |
132 | tmp5 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*5]; | 132 | tmp5 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*5]; |
133 | tmp3 = dataptr[DCTSIZE*3] + dataptr[DCTSIZE*4]; | 133 | tmp3 = dataptr[DCTSIZE*3] + dataptr[DCTSIZE*4]; |
134 | tmp4 = dataptr[DCTSIZE*3] - dataptr[DCTSIZE*4]; | 134 | tmp4 = dataptr[DCTSIZE*3] - dataptr[DCTSIZE*4]; |
135 | 135 | ||
136 | /* Even part */ | 136 | /* Even part */ |
137 | 137 | ||
138 | tmp10 = tmp0 + tmp3; /* phase 2 */ | 138 | tmp10 = tmp0 + tmp3; /* phase 2 */ |
139 | tmp13 = tmp0 - tmp3; | 139 | tmp13 = tmp0 - tmp3; |
140 | tmp11 = tmp1 + tmp2; | 140 | tmp11 = tmp1 + tmp2; |
141 | tmp12 = tmp1 - tmp2; | 141 | tmp12 = tmp1 - tmp2; |
142 | 142 | ||
143 | dataptr[DCTSIZE*0] = tmp10 + tmp11; /* phase 3 */ | 143 | dataptr[DCTSIZE*0] = tmp10 + tmp11; /* phase 3 */ |
144 | dataptr[DCTSIZE*4] = tmp10 - tmp11; | 144 | dataptr[DCTSIZE*4] = tmp10 - tmp11; |
145 | 145 | ||
146 | z1 = (tmp12 + tmp13) * ((FAST_FLOAT) 0.707106781); /* c4 */ | 146 | z1 = (tmp12 + tmp13) * ((FAST_FLOAT) 0.707106781); /* c4 */ |
147 | dataptr[DCTSIZE*2] = tmp13 + z1; /* phase 5 */ | 147 | dataptr[DCTSIZE*2] = tmp13 + z1; /* phase 5 */ |
148 | dataptr[DCTSIZE*6] = tmp13 - z1; | 148 | dataptr[DCTSIZE*6] = tmp13 - z1; |
149 | 149 | ||
150 | /* Odd part */ | 150 | /* Odd part */ |
151 | 151 | ||
152 | tmp10 = tmp4 + tmp5; /* phase 2 */ | 152 | tmp10 = tmp4 + tmp5; /* phase 2 */ |
153 | tmp11 = tmp5 + tmp6; | 153 | tmp11 = tmp5 + tmp6; |
154 | tmp12 = tmp6 + tmp7; | 154 | tmp12 = tmp6 + tmp7; |
155 | 155 | ||
156 | /* The rotator is modified from fig 4-8 to avoid extra negations. */ | 156 | /* The rotator is modified from fig 4-8 to avoid extra negations. */ |
157 | z5 = (tmp10 - tmp12) * ((FAST_FLOAT) 0.382683433); /* c6 */ | 157 | z5 = (tmp10 - tmp12) * ((FAST_FLOAT) 0.382683433); /* c6 */ |
158 | z2 = ((FAST_FLOAT) 0.541196100) * tmp10 + z5; /* c2-c6 */ | 158 | z2 = ((FAST_FLOAT) 0.541196100) * tmp10 + z5; /* c2-c6 */ |
159 | z4 = ((FAST_FLOAT) 1.306562965) * tmp12 + z5; /* c2+c6 */ | 159 | z4 = ((FAST_FLOAT) 1.306562965) * tmp12 + z5; /* c2+c6 */ |
160 | z3 = tmp11 * ((FAST_FLOAT) 0.707106781); /* c4 */ | 160 | z3 = tmp11 * ((FAST_FLOAT) 0.707106781); /* c4 */ |
161 | 161 | ||
162 | z11 = tmp7 + z3; /* phase 5 */ | 162 | z11 = tmp7 + z3; /* phase 5 */ |
163 | z13 = tmp7 - z3; | 163 | z13 = tmp7 - z3; |
164 | 164 | ||
165 | dataptr[DCTSIZE*5] = z13 + z2; /* phase 6 */ | 165 | dataptr[DCTSIZE*5] = z13 + z2; /* phase 6 */ |
166 | dataptr[DCTSIZE*3] = z13 - z2; | 166 | dataptr[DCTSIZE*3] = z13 - z2; |
167 | dataptr[DCTSIZE*1] = z11 + z4; | 167 | dataptr[DCTSIZE*1] = z11 + z4; |
168 | dataptr[DCTSIZE*7] = z11 - z4; | 168 | dataptr[DCTSIZE*7] = z11 - z4; |
169 | 169 | ||
170 | dataptr++; /* advance pointer to next column */ | 170 | dataptr++; /* advance pointer to next column */ |
171 | } | 171 | } |
172 | } | 172 | } |
173 | 173 | ||
174 | #endif /* DCT_FLOAT_SUPPORTED */ | 174 | #endif /* DCT_FLOAT_SUPPORTED */ |