1 files changed, 179 insertions, 0 deletions
diff --git a/src/gallium/auxiliary/vl/vl_csc.c b/src/gallium/auxiliary/vl/vl_csc.c
new file mode 100644
index 00000000000..828cebe4ed4
--- /dev/null
+++ b/src/gallium/auxiliary/vl/vl_csc.c
@@ -0,0 +1,179 @@
+#include "vl_csc.h"
+#include <util/u_math.h>
+#include <util/u_debug.h>
+
+/*
+ * Color space conversion formulas
+ *
+ * To convert YCbCr to RGB,
+ *    vec4  ycbcr, rgb
+ *    mat44 csc
+ *    rgb = csc * ycbcr
+ *
+ * To calculate the color space conversion matrix csc with ProcAmp adjustments,
+ *    mat44 csc, cstd, procamp, bias
+ *    csc = cstd * (procamp * bias)
+ *
+ * Where cstd is a matrix corresponding to one of the color standards (BT.601, BT.709, etc)
+ * adjusted for the kind of YCbCr -> RGB mapping wanted (1:1, full),
+ * bias is a matrix corresponding to the kind of YCbCr -> RGB mapping wanted (1:1, full)
+ *
+ * To calculate procamp,
+ *    mat44 procamp, hue, saturation, brightness, contrast
+ *    procamp = brightness * (saturation * (contrast * hue))
+ * Alternatively,
+ *    procamp = saturation * (brightness * (contrast * hue))
+ *
+ * contrast
+ * [ c, 0, 0, 0]
+ * [ 0, c, 0, 0]
+ * [ 0, 0, c, 0]
+ * [ 0, 0, 0, 1]
+ *
+ * brightness
+ * [ 1, 0, 0, b]
+ * [ 0, 1, 0, 0]
+ * [ 0, 0, 1, 0]
+ * [ 0, 0, 0, 1]
+ *
+ * saturation
+ * [ 1, 0, 0, 0]
+ * [ 0, s, 0, 0]
+ * [ 0, 0, s, 0]
+ * [ 0, 0, 0, 1]
+ *
+ * hue
+ * [ 1,       0,      0, 0]
+ * [ 0,  cos(h), sin(h), 0]
+ * [ 0, -sin(h), cos(h), 0]
+ * [ 0,       0,      0, 1]
+ *
+ * procamp
+ * [ c,           0,          0, b]
+ * [ 0,  c*s*cos(h), c*s*sin(h), 0]
+ * [ 0, -c*s*sin(h), c*s*cos(h), 0]
+ * [ 0,           0,          0, 1]
+ *
+ * bias
+ * [ 1, 0, 0,  ybias]
+ * [ 0, 1, 0, cbbias]
+ * [ 0, 0, 1, crbias]
+ * [ 0, 0, 0,      1]
+ *
+ * csc
+ * [ 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))]
+ * [ 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))]
+ * [ 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))]
+ * [ 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))]
+ */
+
+/*
+ * Converts ITU-R BT.601 YCbCr pixels to RGB pixels where:
+ * Y is in [16,235], Cb and Cr are in [16,240]
+ * R, G, and B are in [16,235]
+ */
+static const float bt_601[16] =
+{
+   1.0f,  0.0f,    1.371f, 0.0f,
+   1.0f, -0.336f, -0.698f, 0.0f,
+   1.0f,  1.732f,  0.0f,   0.0f,
+   0.0f,  0.0f,    0.0f,   1.0f
+};
+
+/*
+ * Converts ITU-R BT.601 YCbCr pixels to RGB pixels where:
+ * Y is in [16,235], Cb and Cr are in [16,240]
+ * R, G, and B are in [0,255]
+ */
+static const float bt_601_full[16] =
+{
+   1.164f,  0.0f,    1.596f, 0.0f,
+   1.164f, -0.391f, -0.813f, 0.0f,
+   1.164f,  2.018f,  0.0f,   0.0f,
+   0.0f,    0.0f,    0.0f,   1.0f
+};
+
+/*
+ * Converts ITU-R BT.709 YCbCr pixels to RGB pixels where:
+ * Y is in [16,235], Cb and Cr are in [16,240]
+ * R, G, and B are in [16,235]
+ */
+static const float bt_709[16] =
+{
+   1.0f,  0.0f,    1.540f, 0.0f,
+   1.0f, -0.183f, -0.459f, 0.0f,
+   1.0f,  1.816f,  0.0f,   0.0f,
+   0.0f,  0.0f,    0.0f,   1.0f
+};
+
+/*
+ * Converts ITU-R BT.709 YCbCr pixels to RGB pixels where:
+ * Y is in [16,235], Cb and Cr are in [16,240]
+ * R, G, and B are in [0,255]
+ */
+static const float bt_709_full[16] =
+{
+   1.164f,  0.0f,    1.793f, 0.0f,
+   1.164f, -0.213f, -0.534f, 0.0f,
+   1.164f,  2.115f,  0.0f,   0.0f,
+   0.0f,    0.0f,    0.0f,   1.0f
+};
+
+static const float identity[16] =
+{
+   1.0f, 0.0f, 0.0f, 0.0f,
+   0.0f, 1.0f, 0.0f, 0.0f,
+   0.0f, 0.0f, 1.0f, 0.0f,
+   0.0f, 0.0f, 0.0f, 1.0f
+};
+
+void vl_csc_get_matrix(enum VL_CSC_COLOR_STANDARD cs,
+                       struct vl_procamp *procamp,
+                       bool full_range,
+                       float *matrix)
+{
+   float ybias = full_range ? -16.0f/255.0f : 0.0f;
+   float cbbias = -128.0f/255.0f;
+   float crbias = -128.0f/255.0f;
+   float c = procamp ? procamp->contrast : 1.0f;
+   float s = procamp ? procamp->saturation : 1.0f;
+   float b = procamp ? procamp->brightness : 0.0f;
+   float h = procamp ? procamp->hue : 0.0f;
+   const float *cstd;
+
+   assert(matrix);
+
+   switch (cs) {
+      case VL_CSC_COLOR_STANDARD_BT_601:
+         cstd = full_range ? &bt_601_full[0] : &bt_601[0];
+         break;
+      case VL_CSC_COLOR_STANDARD_BT_709:
+         cstd = full_range ? &bt_709_full[0] : &bt_709[0];
+         break;
+      case VL_CSC_COLOR_STANDARD_IDENTITY:
+      default:
+         assert(cs == VL_CSC_COLOR_STANDARD_IDENTITY);
+         memcpy(matrix, &identity[0], sizeof(float) * 16);
+         return;
+   }
+
+   matrix[ 0] = c*cstd[ 0];
+   matrix[ 1] = c*cstd[ 1]*s*cosf(h) - c*cstd[ 2]*s*sinf(h);
+   matrix[ 2] = c*cstd[ 2]*s*cosf(h) + c*cstd[ 1]*s*sinf(h);
+   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));
+
+   matrix[ 4] = c*cstd[ 4];
+   matrix[ 5] = c*cstd[ 5]*s*cosf(h) - c*cstd[ 6]*s*sinf(h);
+   matrix[ 6] = c*cstd[ 6]*s*cosf(h) + c*cstd[ 5]*s*sinf(h);
+   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));
+
+   matrix[ 8] = c*cstd[ 8];
+   matrix[ 9] = c*cstd[ 9]*s*cosf(h) - c*cstd[10]*s*sinf(h);
+   matrix[10] = c*cstd[10]*s*cosf(h) + c*cstd[ 9]*s*sinf(h);
+   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));
+
+   matrix[12] = c*cstd[12];
+   matrix[13] = c*cstd[13]*s*cos(h) - c*cstd[14]*s*sin(h);
+   matrix[14] = c*cstd[14]*s*cos(h) + c*cstd[13]*s*sin(h);
+   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));
+}