commit ff0286325a3dd1f4fe7e29e78341b9bd63e1725c
parent e650c912ba86c84cdad466674a0ca0c4ebadef9c
Author: Mattias Andrée <maandree@kth.se>
Date: Fri, 14 Jul 2017 21:15:32 +0200
blind-matrix-{rotate,shear}: add -d
Signed-off-by: Mattias Andrée <maandree@kth.se>
Diffstat:
5 files changed, 90 insertions(+), 10 deletions(-)
diff --git a/man/blind-matrix-rotate.1 b/man/blind-matrix-rotate.1
@@ -3,7 +3,7 @@
blind-matrix-rotate - Create an affine 2D-transformation matrix for rotation
.SH SYNOPSIS
.B blind-matrix-rotate
-[-c]
+[-cd]
.SH DESCRIPTION
.B blind-matrix-rotate
creates an affine 2D-transformation matrix for
@@ -28,9 +28,21 @@ Create different matrices for each channel. Use
values from each channel in stdin to create
matrices whose values are stored in the same
channels in stdout.
+.TP
+.B -d
+Input angles in degrees rather than radians.
.SH NOTES
The image is rotated anti-clockwise if the Y-axis
grows upwards rather than downwards.
+.P
+Due to truncation error, when rotating a multiple
+of 90 degrees, it is preferable to use
+.B -d
+with lets
+.B blind-matrix-rotate
+eliminate the error. If this is not done,
+.BR blind-invert-matrix (1)
+may return odd results.
.SH SEE ALSO
.BR blind (7),
.BR blind-from-text (1),
diff --git a/man/blind-matrix-shear.1 b/man/blind-matrix-shear.1
@@ -3,7 +3,7 @@
blind-matrix-shear - Create an affine 2D-transformation matrix for shearing
.SH SYNOPSIS
.B blind-matrix-shear
-[-ac]
+[-a [-d]] [-c]
.SH DESCRIPTION
.B blind-matrix-shear
creates an affine 2D-transformation matrix for
@@ -37,6 +37,9 @@ Create different matrices for each channel. Use
values from each channel in stdin to create
matrices whose values are stored in the same
channels in stdout.
+.TP
+.B -d
+Input angles in degrees rather than radians.
.SH NOTES
The description assumes the Y-axis grows downwards.
.P
diff --git a/src/blind-matrix-rotate.c b/src/blind-matrix-rotate.c
@@ -1,9 +1,10 @@
/* See LICENSE file for copyright and license details. */
#include "common.h"
-USAGE("[-c]")
+USAGE("[-cd]")
static int per_channel = 0;
+static int in_degrees = 0;
#define PROCESS(TYPE)\
do {\
@@ -19,15 +20,25 @@ static int per_channel = 0;
}\
\
while (eread_frame(stream, buf)) {\
- if (per_channel) {\
+ if (per_channel && in_degrees) {\
+ for (i = 0; i < 4; i++) {\
+ matrix[4][i] = matrix[0][i] = degcos(buf[i]);\
+ matrix[3][i] = -(matrix[1][i] = degsin(buf[i]));\
+ }\
+ } else if (per_channel) {\
for (i = 0; i < 4; i++) {\
matrix[4][i] = matrix[0][i] = cos(buf[i]);\
matrix[3][i] = -(matrix[1][i] = sin(buf[i]));\
}\
} else {\
buf[1] *= buf[3];\
- matrix[4][0] = matrix[0][0] = cos(buf[1]);\
- matrix[3][0] = -(matrix[1][0] = sin(buf[1]));\
+ if (in_degrees) {\
+ matrix[4][0] = matrix[0][0] = degcos(buf[1]);\
+ matrix[3][0] = -(matrix[1][0] = degsin(buf[1]));\
+ } else {\
+ matrix[4][0] = matrix[0][0] = cos(buf[1]);\
+ matrix[3][0] = -(matrix[1][0] = sin(buf[1]));\
+ }\
matrix[0][3] = matrix[0][2] = matrix[0][1] = matrix[0][0];\
matrix[1][3] = matrix[1][2] = matrix[1][1] = matrix[1][0];\
matrix[3][3] = matrix[3][2] = matrix[3][1] = matrix[3][0];\
@@ -50,6 +61,9 @@ main(int argc, char *argv[])
case 'c':
per_channel = 1;
break;
+ case 'd':
+ in_degrees = 1;
+ break;
default:
usage();
} ARGEND;
diff --git a/src/blind-matrix-shear.c b/src/blind-matrix-shear.c
@@ -1,16 +1,18 @@
/* See LICENSE file for copyright and license details. */
#include "common.h"
-USAGE("[-ac]")
+USAGE("[-a [-d]][c]")
static int by_angle = 0;
static int per_channel = 0;
+static int in_degrees = 0;
#define PROCESS(TYPE)\
do {\
typedef TYPE pixel_t[4];\
pixel_t matrix[9];\
pixel_t buf[2];\
+ TYPE conv = in_degrees ? (TYPE)(M_PI / 180.) : 1;\
int i;\
\
for (i = 0; i < 4; i++) {\
@@ -22,8 +24,8 @@ static int per_channel = 0;
while (eread_frame(stream, buf)) {\
if (by_angle) {\
for (i = !per_channel; i < (per_channel ? 4 : 2); i++) {\
- buf[0][i] = tan(buf[0][i]);\
- buf[1][i] = tan(buf[1][i]);\
+ buf[0][i] = tan(buf[0][i] * conv);\
+ buf[1][i] = tan(buf[1][i] * conv);\
}\
}\
if (per_channel) {\
@@ -55,11 +57,14 @@ main(int argc, char *argv[])
case 'c':
per_channel = 1;
break;
+ case 'd':
+ in_degrees = 1;
+ break;
default:
usage();
} ARGEND;
- if (argc)
+ if (argc || (in_degrees && !by_angle))
usage();
eopen_stream(&stream, NULL);
diff --git a/src/video-math.h b/src/video-math.h
@@ -31,6 +31,50 @@ posmodf(float a, float b)
return x < 0 ? x + b : x;
}
+static inline double
+degsin(double u)
+{
+ if (!fmod(u, 90)) {
+ int64_t v = u;
+ v = ((v / 90) % 4 + 4) % 4;
+ return ((double[]){0, 1, 0, -1})[v];
+ }
+ return sin(u * (M_PI / 180.0));
+}
+
+static inline float
+degsinf(float u)
+{
+ if (!fmodf(u, 90)) {
+ int64_t v = u;
+ v = ((v / 90) % 4 + 4) % 4;
+ return ((float[]){0, 1, 0, -1})[v];
+ }
+ return sin(u * (float)(M_PI / 180.0));
+}
+
+static inline double
+degcos(double u)
+{
+ if (!fmod(u, 90)) {
+ int64_t v = u;
+ v = ((v / 90) % 4 + 4) % 4;
+ return ((double[]){1, 0, -1, 0})[v];
+ }
+ return cos(u * (M_PI / 180.0));
+}
+
+static inline float
+degcosf(float u)
+{
+ if (!fmodf(u, 90)) {
+ int64_t v = u;
+ v = ((v / 90) % 4 + 4) % 4;
+ return ((float[]){1, 0, -1, 0})[v];
+ }
+ return cos(u * (float)(M_PI / 180.0));
+}
+
#define GENERIC(TYPE, FUNC, ...)\
TYPE: FUNC(__VA_ARGS__),\
TYPE *: FUNC(__VA_ARGS__),\
@@ -73,6 +117,8 @@ posmodf(float a, float b)
#define sin(...) MATH_GENERIC_1(sin, __VA_ARGS__)
#define tan(...) MATH_GENERIC_1(tan, __VA_ARGS__)
#define atan2(...) MATH_GENERIC_N(atan2, __VA_ARGS__)
+#define degcos(...) MATH_GENERIC_1(degcos, __VA_ARGS__)
+#define degsin(...) MATH_GENERIC_1(degsin, __VA_ARGS__)
#define srgb_encode(...) BLIND_GENERIC_1(srgb_encode, __VA_ARGS__)
#define srgb_decode(...) BLIND_GENERIC_1(srgb_decode, __VA_ARGS__)
