1 /**************************************************************************
3 * Copyright 2009 Younes Manton.
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
26 **************************************************************************/
29 #include <util/u_math.h>
30 #include <util/u_debug.h>
33 * Color space conversion formulas
35 * To convert YCbCr to RGB,
40 * To calculate the color space conversion matrix csc with ProcAmp adjustments,
41 * mat44 csc, cstd, procamp, bias
42 * csc = cstd * (procamp * bias)
44 * Where cstd is a matrix corresponding to one of the color standards (BT.601, BT.709, etc)
45 * adjusted for the kind of YCbCr -> RGB mapping wanted (1:1, full),
46 * bias is a matrix corresponding to the kind of YCbCr -> RGB mapping wanted (1:1, full)
48 * To calculate procamp,
49 * mat44 procamp, hue, saturation, brightness, contrast
50 * procamp = brightness * (saturation * (contrast * hue))
52 * procamp = saturation * (brightness * (contrast * hue))
74 * [ 0, cos(h), sin(h), 0]
75 * [ 0, -sin(h), cos(h), 0]
80 * [ 0, c*s*cos(h), c*s*sin(h), 0]
81 * [ 0, -c*s*sin(h), c*s*cos(h), 0]
91 * [ c*cstd[ 0], c*cstd[ 1]*s*cos(h) - c*cstd[ 2]*s*sin(h), c*cstd[ 2]*s*cos(h) + c*cstd[ 1]*s*sin(h), cstd[ 3] + cstd[ 0]*(b + c*ybias) + cstd[ 1]*(c*cbbias*s*cos(h) + c*crbias*s*sin(h)) + cstd[ 2]*(c*crbias*s*cos(h) - c*cbbias*s*sin(h))]
92 * [ c*cstd[ 4], c*cstd[ 5]*s*cos(h) - c*cstd[ 6]*s*sin(h), c*cstd[ 6]*s*cos(h) + c*cstd[ 5]*s*sin(h), cstd[ 7] + cstd[ 4]*(b + c*ybias) + cstd[ 5]*(c*cbbias*s*cos(h) + c*crbias*s*sin(h)) + cstd[ 6]*(c*crbias*s*cos(h) - c*cbbias*s*sin(h))]
93 * [ c*cstd[ 8], c*cstd[ 9]*s*cos(h) - c*cstd[10]*s*sin(h), c*cstd[10]*s*cos(h) + c*cstd[ 9]*s*sin(h), cstd[11] + cstd[ 8]*(b + c*ybias) + cstd[ 9]*(c*cbbias*s*cos(h) + c*crbias*s*sin(h)) + cstd[10]*(c*crbias*s*cos(h) - c*cbbias*s*sin(h))]
94 * [ c*cstd[12], c*cstd[13]*s*cos(h) - c*cstd[14]*s*sin(h), c*cstd[14]*s*cos(h) + c*cstd[13]*s*sin(h), cstd[15] + cstd[12]*(b + c*ybias) + cstd[13]*(c*cbbias*s*cos(h) + c*crbias*s*sin(h)) + cstd[14]*(c*crbias*s*cos(h) - c*cbbias*s*sin(h))]
98 * Converts ITU-R BT.601 YCbCr pixels to RGB pixels where:
99 * Y is in [16,235], Cb and Cr are in [16,240]
100 * R, G, and B are in [16,235]
102 static const float bt_601
[16] =
104 1.0f
, 0.0f
, 1.371f
, 0.0f
,
105 1.0f
, -0.336f
, -0.698f
, 0.0f
,
106 1.0f
, 1.732f
, 0.0f
, 0.0f
,
107 0.0f
, 0.0f
, 0.0f
, 1.0f
111 * Converts ITU-R BT.601 YCbCr pixels to RGB pixels where:
112 * Y is in [16,235], Cb and Cr are in [16,240]
113 * R, G, and B are in [0,255]
115 static const float bt_601_full
[16] =
117 1.164f
, 0.0f
, 1.596f
, 0.0f
,
118 1.164f
, -0.391f
, -0.813f
, 0.0f
,
119 1.164f
, 2.018f
, 0.0f
, 0.0f
,
120 0.0f
, 0.0f
, 0.0f
, 1.0f
124 * Converts ITU-R BT.709 YCbCr pixels to RGB pixels where:
125 * Y is in [16,235], Cb and Cr are in [16,240]
126 * R, G, and B are in [16,235]
128 static const float bt_709
[16] =
130 1.0f
, 0.0f
, 1.540f
, 0.0f
,
131 1.0f
, -0.183f
, -0.459f
, 0.0f
,
132 1.0f
, 1.816f
, 0.0f
, 0.0f
,
133 0.0f
, 0.0f
, 0.0f
, 1.0f
137 * Converts ITU-R BT.709 YCbCr pixels to RGB pixels where:
138 * Y is in [16,235], Cb and Cr are in [16,240]
139 * R, G, and B are in [0,255]
141 static const float bt_709_full
[16] =
143 1.164f
, 0.0f
, 1.793f
, 0.0f
,
144 1.164f
, -0.213f
, -0.534f
, 0.0f
,
145 1.164f
, 2.115f
, 0.0f
, 0.0f
,
146 0.0f
, 0.0f
, 0.0f
, 1.0f
149 static const float identity
[16] =
151 1.0f
, 0.0f
, 0.0f
, 0.0f
,
152 0.0f
, 1.0f
, 0.0f
, 0.0f
,
153 0.0f
, 0.0f
, 1.0f
, 0.0f
,
154 0.0f
, 0.0f
, 0.0f
, 1.0f
157 void vl_csc_get_matrix(enum VL_CSC_COLOR_STANDARD cs
,
158 struct vl_procamp
*procamp
,
162 float ybias
= full_range
? -16.0f
/255.0f
: 0.0f
;
163 float cbbias
= -128.0f
/255.0f
;
164 float crbias
= -128.0f
/255.0f
;
165 float c
= procamp
? procamp
->contrast
: 1.0f
;
166 float s
= procamp
? procamp
->saturation
: 1.0f
;
167 float b
= procamp
? procamp
->brightness
: 0.0f
;
168 float h
= procamp
? procamp
->hue
: 0.0f
;
174 case VL_CSC_COLOR_STANDARD_BT_601
:
175 cstd
= full_range
? &bt_601_full
[0] : &bt_601
[0];
177 case VL_CSC_COLOR_STANDARD_BT_709
:
178 cstd
= full_range
? &bt_709_full
[0] : &bt_709
[0];
180 case VL_CSC_COLOR_STANDARD_IDENTITY
:
182 assert(cs
== VL_CSC_COLOR_STANDARD_IDENTITY
);
183 memcpy(matrix
, &identity
[0], sizeof(float) * 16);
187 matrix
[ 0] = c
*cstd
[ 0];
188 matrix
[ 1] = c
*cstd
[ 1]*s
*cosf(h
) - c
*cstd
[ 2]*s
*sinf(h
);
189 matrix
[ 2] = c
*cstd
[ 2]*s
*cosf(h
) + c
*cstd
[ 1]*s
*sinf(h
);
190 matrix
[ 3] = cstd
[ 3] + cstd
[ 0]*(b
+ c
*ybias
) + cstd
[ 1]*(c
*cbbias
*s
*cosf(h
) + c
*crbias
*s
*sinf(h
)) + cstd
[ 2]*(c
*crbias
*s
*cosf(h
) - c
*cbbias
*s
*sinf(h
));
192 matrix
[ 4] = c
*cstd
[ 4];
193 matrix
[ 5] = c
*cstd
[ 5]*s
*cosf(h
) - c
*cstd
[ 6]*s
*sinf(h
);
194 matrix
[ 6] = c
*cstd
[ 6]*s
*cosf(h
) + c
*cstd
[ 5]*s
*sinf(h
);
195 matrix
[ 7] = cstd
[ 7] + cstd
[ 4]*(b
+ c
*ybias
) + cstd
[ 5]*(c
*cbbias
*s
*cosf(h
) + c
*crbias
*s
*sinf(h
)) + cstd
[ 6]*(c
*crbias
*s
*cosf(h
) - c
*cbbias
*s
*sinf(h
));
197 matrix
[ 8] = c
*cstd
[ 8];
198 matrix
[ 9] = c
*cstd
[ 9]*s
*cosf(h
) - c
*cstd
[10]*s
*sinf(h
);
199 matrix
[10] = c
*cstd
[10]*s
*cosf(h
) + c
*cstd
[ 9]*s
*sinf(h
);
200 matrix
[11] = cstd
[11] + cstd
[ 8]*(b
+ c
*ybias
) + cstd
[ 9]*(c
*cbbias
*s
*cosf(h
) + c
*crbias
*s
*sinf(h
)) + cstd
[10]*(c
*crbias
*s
*cosf(h
) - c
*cbbias
*s
*sinf(h
));
202 matrix
[12] = c
*cstd
[12];
203 matrix
[13] = c
*cstd
[13]*s
*cos(h
) - c
*cstd
[14]*s
*sin(h
);
204 matrix
[14] = c
*cstd
[14]*s
*cos(h
) + c
*cstd
[13]*s
*sin(h
);
205 matrix
[15] = cstd
[15] + cstd
[12]*(b
+ c
*ybias
) + cstd
[13]*(c
*cbbias
*s
*cos(h
) + c
*crbias
*s
*sin(h
)) + cstd
[14]*(c
*crbias
*s
*cos(h
) - c
*cbbias
*s
*sin(h
));