{ 1.0f, 1.732f, 0.0f, 0.0f, }
};
-/*
- * 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 vl_csc_matrix bt_601_full =
-{
- { 1.164f, 0.0f, 1.596f, 0.0f, },
- { 1.164f, -0.391f, -0.813f, 0.0f, },
- { 1.164f, 2.018f, 0.0f, 0.0f, }
-};
-
/*
* Converts ITU-R BT.709 YCbCr pixels to RGB pixels where:
* Y is in [16,235], Cb and Cr are in [16,240]
};
/*
- * Converts ITU-R BT.709 YCbCr pixels to RGB pixels where:
+ * Converts SMPTE 240M 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]
+ * R, G, and B are in [16,235]
*/
-static const vl_csc_matrix bt_709_full =
-{
- { 1.164f, 0.0f, 1.793f, 0.0f, },
- { 1.164f, -0.213f, -0.534f, 0.0f, },
- { 1.164f, 2.115f, 0.0f, 0.0f, }
-};
-
static const vl_csc_matrix smpte240m =
{
- { 1.0f, 0.0f, 1.582f, 0.0f, },
- { 1.0f, -0.228f, -0.478f, 0.0f, },
- { 1.0f, 1.833f, 0.0f, 0.0f, }
+ { 1.0f, 0.0f, 1.541f, 0.0f, },
+ { 1.0f, -0.221f, -0.466f, 0.0f, },
+ { 1.0f, 1.785f, 0.0f, 0.0f, }
};
-static const vl_csc_matrix smpte240m_full =
-{
- { 1.164f, 0.0f, 1.794f, 0.0f, },
- { 1.164f, -0.258f, -0.543f, 0.0f, },
- { 1.164f, 2.079f, 0.0f, 0.0f, }
+static const vl_csc_matrix bt_709_rev = {
+ { 0.183f, 0.614f, 0.062f, 0.0625f},
+ {-0.101f, -0.338f, 0.439f, 0.5f },
+ { 0.439f, -0.399f, -0.040f, 0.5f }
};
static const vl_csc_matrix identity =
bool full_range,
vl_csc_matrix *matrix)
{
- float ybias = full_range ? -16.0f/255.0f : 0.0f;
float cbbias = -128.0f/255.0f;
float crbias = -128.0f/255.0f;
float s = p->saturation;
float b = p->brightness;
float h = p->hue;
+ float x, y;
const vl_csc_matrix *cstd;
+ if (full_range) {
+ c *= 1.164f; /* Adjust for the y range */
+ b *= 1.164f; /* Adjust for the y range */
+ b -= c * 16.0f / 255.0f; /* Adjust for the y bias */
+ }
+
+ /* Parameter substitutions */
+ x = c * s * cosf(h);
+ y = c * s * sinf(h);
+
assert(matrix);
switch (cs) {
case VL_CSC_COLOR_STANDARD_BT_601:
- cstd = full_range ? &bt_601_full : &bt_601;
+ cstd = &bt_601;
break;
case VL_CSC_COLOR_STANDARD_BT_709:
- cstd = full_range ? &bt_709_full : &bt_709;
+ cstd = &bt_709;
break;
case VL_CSC_COLOR_STANDARD_SMPTE_240M:
- cstd = full_range ? &smpte240m_full : &smpte240m;
+ cstd = &smpte240m;
break;
+ case VL_CSC_COLOR_STANDARD_BT_709_REV:
+ memcpy(matrix, bt_709_rev, sizeof(vl_csc_matrix));
+ return;
case VL_CSC_COLOR_STANDARD_IDENTITY:
default:
assert(cs == VL_CSC_COLOR_STANDARD_IDENTITY);
}
(*matrix)[0][0] = c * (*cstd)[0][0];
- (*matrix)[0][1] = c * (*cstd)[0][1] * s * cosf(h) - c * (*cstd)[0][2] * s * sinf(h);
- (*matrix)[0][2] = c * (*cstd)[0][2] * s * cosf(h) + c * (*cstd)[0][1] * s * sinf(h);
- (*matrix)[0][3] = (*cstd)[0][3] + (*cstd)[0][0] * (b + c * ybias) +
- (*cstd)[0][1] * (c * cbbias * s * cosf(h) + c * crbias * s * sinf(h)) +
- (*cstd)[0][2] * (c * crbias * s * cosf(h) - c * cbbias * s * sinf(h));
+ (*matrix)[0][1] = (*cstd)[0][1] * x - (*cstd)[0][2] * y;
+ (*matrix)[0][2] = (*cstd)[0][2] * x + (*cstd)[0][1] * y;
+ (*matrix)[0][3] = (*cstd)[0][3] + (*cstd)[0][0] * b +
+ (*cstd)[0][1] * (x * cbbias + y * crbias) +
+ (*cstd)[0][2] * (x * crbias - y * cbbias);
(*matrix)[1][0] = c * (*cstd)[1][0];
- (*matrix)[1][1] = c * (*cstd)[1][1] * s * cosf(h) - c * (*cstd)[1][2] * s * sinf(h);
- (*matrix)[1][2] = c * (*cstd)[1][2] * s * cosf(h) + c * (*cstd)[1][1] * s * sinf(h);
- (*matrix)[1][3] = (*cstd)[1][3] + (*cstd)[1][0] * (b + c * ybias) +
- (*cstd)[1][1] * (c * cbbias * s * cosf(h) + c * crbias * s * sinf(h)) +
- (*cstd)[1][2] * (c * crbias * s * cosf(h) - c * cbbias * s * sinf(h));
+ (*matrix)[1][1] = (*cstd)[1][1] * x - (*cstd)[1][2] * y;
+ (*matrix)[1][2] = (*cstd)[1][2] * x + (*cstd)[1][1] * y;
+ (*matrix)[1][3] = (*cstd)[1][3] + (*cstd)[1][0] * b +
+ (*cstd)[1][1] * (x * cbbias + y * crbias) +
+ (*cstd)[1][2] * (x * crbias - y * cbbias);
(*matrix)[2][0] = c * (*cstd)[2][0];
- (*matrix)[2][1] = c * (*cstd)[2][1] * s * cosf(h) - c * (*cstd)[2][2] * s * sinf(h);
- (*matrix)[2][2] = c * (*cstd)[2][2] * s * cosf(h) + c * (*cstd)[2][1] * s * sinf(h);
- (*matrix)[2][3] = (*cstd)[2][3] + (*cstd)[2][0] * (b + c * ybias) +
- (*cstd)[2][1] * (c * cbbias * s * cosf(h) + c * crbias * s * sinf(h)) +
- (*cstd)[2][2] * (c * crbias * s * cosf(h) - c * cbbias * s * sinf(h));
+ (*matrix)[2][1] = (*cstd)[2][1] * x - (*cstd)[2][2] * y;
+ (*matrix)[2][2] = (*cstd)[2][2] * x + (*cstd)[2][1] * y;
+ (*matrix)[2][3] = (*cstd)[2][3] + (*cstd)[2][0] * b +
+ (*cstd)[2][1] * (x * cbbias + y * crbias) +
+ (*cstd)[2][2] * (x * crbias - y * cbbias);
}