OsmoTV: Added more test patterns for TV repair

- improved FUBK
- red screen for DY adjustment
- crosses and dots for convergence adjustment
- EBU color bars
- natural color image

src/tv/color.c

@@ -0,0 +1,73 @@
+/* color test image generator
+ *
+ * (C) 2019 by Andreas Eversberg <jolly@eversberg.eu>
+ * All Rights Reserved
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <math.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include "../libsample/sample.h"
+#include "color.h"
+
+#define RAMP_WIDTH	0.0000002
+
+static struct color_bar {
+	double amplitude, phase;
+} color_bar[8] = {
+	{0.0, 0.0},
+	{0.336, 167.1},
+	{0.474, 283.5},
+	{0.443, 240.7},
+	{0.443, 60.7},
+	{0.474, 103.5},
+	{0.336, 347.1},
+	{0.0, 0.0},
+};
+
+int color_gen_line(sample_t *sample, double x, double samplerate, sample_t *color_u, sample_t *color_v, int v_polarity, double line_start, double line_end)
+{
+	int b = 5;
+	double step = 1.0 / samplerate;
+	int i = 0;
+	double amplitude, Y, U, V, colorphase;
+
+	/* skip x to line_start */
+	while (x < line_start && x < line_end) {
+		i++;
+		x += step;
+	}
+	if (x >= line_end)
+		return i;
+
+	/* color */
+	Y = (1.0 - (double)b / 7.0) * 0.75;
+	amplitude = color_bar[b].amplitude;
+	if (v_polarity < 0)
+		colorphase = (360.0 - color_bar[b].phase) / 180.0 * M_PI;
+	else
+		colorphase = color_bar[b].phase / 180.0 * M_PI;
+	U = cos(colorphase) * amplitude / 2.0;
+	V = sin(colorphase) * amplitude / 2.0;
+	while (x < line_end) {
+		color_u[i] = U;
+		color_v[i] = V;
+		sample[i++] = Y;
+		x += step;
+	}
+
+	return i;
+}