blind

commit 7be1448a633be40aadd41250f99019438af0c688
parent f69ec5134ffc1fc27764ca70d10be92517ec4498
Author: Mattias Andrée <maandree@kth.se>
Date:   Sat, 13 May 2017 22:55:41 +0200

Add blind-kernel

Signed-off-by: Mattias Andrée <maandree@kth.se>

Diffstat:
M
Makefile
 | 
1
+
M
TODO
 | 
2
++
A
src/blind-kernel.c
 | 
137
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

3 files changed, 140 insertions(+), 0 deletions(-)
diff --git a/Makefile b/Makefile
@@ -21,6 +21,7 @@ BIN =\
 	blind-from-video\
 	blind-gauss-blur\
 	blind-invert-luma\
+	blind-kernel\
 	blind-make-kernel\
 	blind-next-frame\
 	blind-read-head\
diff --git a/TODO b/TODO
@@ -16,6 +16,8 @@ blind-affine-colour	apply an affine transformation to the colour of each pixel,
 blind-invert-chroma	invert the chroma
 blind-from-sent		convert a sent presentation to a one-frame-per-slide blind video.
 
+blind-kirsch		https://en.wikipedia.org/wiki/Kirsch_operator
+
 blind-from-video: add options to:
 	* just run ffmpeg just print the output
 	* convert output from the option above to blind's format,
diff --git a/src/blind-kernel.c b/src/blind-kernel.c
@@ -0,0 +1,137 @@
+/* See LICENSE file for copyright and license details. */
+#include "stream.h"
+#include "util.h"
+
+#include <string.h>
+
+USAGE("[-xyza] kernel [parameter] ...")
+
+#define SUBUSAGE(FORMAT) "Usage: %s [-xyza] " FORMAT, argv0
+#define MATRIX(...) ((const double[]){__VA_ARGS__});
+#define STREQ3(A, B1, B2, B3) (!strcmp(A, B1) || !strcmp(A, B2) || !strcmp(A, B3))
+
+#define LIST_KERNELS\
+	X(kernel_kirsch, "kirsch")\
+	X(kernel_box_blur, "box blur")\
+	X(kernel_sharpen, "sharpen")
+
+static const double *
+kernel_kirsch(int argc, char *argv[], size_t *rows, size_t *cols, double **free_this)
+{
+	*free_this = NULL;
+	*rows = *cols = 3;
+	if (argc != 1)
+		eprintf(SUBUSAGE("'kirsch' direction"));
+	if (STREQ3(argv[0], "1", "N",  "N"))  return MATRIX( 5,  5,  5,   -3, 0, -3,   -3, -3, -3);
+	if (STREQ3(argv[0], "2", "NW", "WN")) return MATRIX( 5,  5, -3,    5, 0, -3,   -3, -3, -3);
+	if (STREQ3(argv[0], "3", "W",  "W"))  return MATRIX( 5, -3, -3,    5, 0, -3,    5, -3, -3);
+	if (STREQ3(argv[0], "4", "SW", "WS")) return MATRIX(-3, -3, -3,    5, 0, -3,    5,  5, -3);
+	if (STREQ3(argv[0], "5", "S",  "S"))  return MATRIX(-3, -3, -3,   -3, 0, -3,    5,  5,  5);
+	if (STREQ3(argv[0], "6", "SE", "ES")) return MATRIX(-3, -3, -3,   -3, 0,  5,   -3,  5,  5);
+	if (STREQ3(argv[0], "7", "E",  "E"))  return MATRIX(-3, -3,  5,   -3, 0,  5,   -3, -3,  5);
+	if (STREQ3(argv[0], "8", "NE", "EN")) return MATRIX(-3,  5,  5,   -3, 0,  5,   -3, -3, -3);
+	eprintf("Unrecognised direction: %s\n", argv[0]);
+	return NULL;
+}
+
+static const double *
+kernel_box_blur(int argc, char *argv[], size_t *rows, size_t *cols, double **free_this)
+{
+	size_t sx, sy, i, n;
+	double *cells, value;
+	*free_this = NULL;
+	*rows = *cols = 3;
+	if (argc > 3)
+		eprintf(SUBUSAGE("'box blur' [spread | x-spread y-spread]"));
+	if (!argc)
+		return MATRIX(1.0 / 9.0,  1.0 / 9.0,  1.0 / 9.0,
+			      1.0 / 9.0,  1.0 / 9.0,  1.0 / 9.0,
+			      1.0 / 9.0,  1.0 / 9.0,  1.0 / 9.0);
+	if (argc == 1) {
+		sx = sy = etozu_arg("spread", argv[0], 0, SIZE_MAX / 2);
+	} else {
+		sx = etozu_arg("x-spread", argv[0], 0, SIZE_MAX / 2);
+		sy = etozu_arg("y-spread", argv[1], 0, SIZE_MAX / 2);
+	}
+	*rows = 2 * sy + 1;
+	*cols = 2 * sx + 1;
+	*free_this = cells = emalloc2(*rows, *cols);
+	n = (2 * sy + 1) * (2 * sx + 1);
+	value = 1 / (double)n;
+	for (i = 0; i < n; i++)
+		cells[i] = value;
+	return cells;
+}
+
+static const double *
+kernel_sharpen(int argc, char *argv[], size_t *rows, size_t *cols, double **free_this)
+{
+	*free_this = NULL;
+	*rows = *cols = 3;
+	if (argc)
+		eprintf(SUBUSAGE("'sharpen'"));
+	return MATRIX(0, -1, 0,  -1, 5, -1,  0, -1, -0);
+	(void) argv;
+}
+
+int
+main(int argc, char *argv[])
+{
+	int null_x = 1, null_y = 1, null_z = 1, null_a = 1;
+	size_t rows, cols, y, x, n;
+	const double *kernel, *kern;
+	double *buffer, *buf, *free_this;
+
+	ARGBEGIN {
+	case 'x':
+		null_x = 0;
+		break;
+	case 'y':
+		null_y = 0;
+		break;
+	case 'z':
+		null_z = 0;
+		break;
+	case 'a':
+		null_a = 0;
+		break;
+	default:
+		usage();
+	} ARGEND;
+
+	if (null_x && null_y && null_z && null_a)
+		null_x = null_y = null_z = null_a = 0;
+
+	if (0);
+#define X(FUNC, NAME)\
+	else if (!strcmp(argv[0], NAME))\
+		kernel = FUNC(argc, argv + 1, &rows, &cols, &free_this);
+	LIST_KERNELS
+#undef X
+	else
+		eprintf("unrecognised kernel: %s\n", argv[0]);
+
+	FPRINTF_HEAD(stdout, (size_t)1, cols, rows, "xyza");
+	efflush(stdout, "<stdout>");
+
+	buffer = emalloc2(cols, 4 * sizeof(double));
+	n = cols * 4 * sizeof(double);
+
+	kern = kernel;
+	for (y = 0; y < rows; y++) {
+		buf = buffer;
+		for (x = 0; x < cols; x++) {
+			buf[0] = null_x ? 0.0 : *kern;
+			buf[1] = null_y ? 0.0 : *kern;
+			buf[2] = null_z ? 0.0 : *kern;
+			buf[3] = null_a ? 0.0 : *kern;
+			buf += 4;
+			kern++;
+		}
+		ewriteall(STDOUT_FILENO, buffer, n, "<stdout>");
+	}
+
+	free(buffer);
+	free(free_this);
+	return 0;
+}