commit 4621e6f35cda10654d2bbfb4df579ec89fb7f99d
parent fc3bad11b3628c3b77df97327f1cdaf19d96aa9e
Author: Mattias Andrée <maandree@kth.se>
Date: Fri, 14 Jul 2017 19:25:21 +0200
Add blind-invert-matrix
Signed-off-by: Mattias Andrée <maandree@kth.se>
Diffstat:
6 files changed, 175 insertions(+), 0 deletions(-)
diff --git a/Makefile b/Makefile
@@ -39,6 +39,7 @@ BIN =\
blind-hexagon-tessellation\
blind-interleave\
blind-invert-luma\
+ blind-invert-matrix\
blind-linear-gradient\
blind-make-kernel\
blind-matrix-orthoproject\
diff --git a/README b/README
@@ -111,6 +111,9 @@ UTILITIES
blind-invert-luma(1)
Invert the luminosity of a video
+ blind-invert-matrix(1)
+ Invert matrix-video
+
blind-linear-gradient(1)
Generate a video with a linear gradient
diff --git a/man/blind-invert-matrix.1 b/man/blind-invert-matrix.1
@@ -0,0 +1,35 @@
+.TH BLIND-INVERT-MATRIX 1 blind
+.SH NAME
+blind-invert-matrix - Invert matrix-vidoes
+.SH SYNOPSIS
+.B blind-invert-matrix
+[-e]
+.SH DESCRIPTION
+.B blind-invert-matrix
+reads a video representing a matrix from
+stdin, inverts it, and prints the results
+to stdout.
+.P
+The matrix must be at least as wide as it
+is tall. If the matrix is wider than it is
+tall, it is treated as an augmented matrix,
+and the unaugmented square matrix is
+eliminated to the identity matrix and the
+resuling augment is printed.
+.SH OPTIONS
+.TP
+.B -e
+Apply optimisation that assumes all channels
+are identical.
+.SH SEE ALSO
+.BR blind (7),
+.BR blind-multiply-matrices (1),
+.BR blind-transpose (1),
+.BR blind-flip (1),
+.BR blind-flop (1),
+.BR blind-rotate-90 (1),
+.BR blind-rotate-180 (1),
+.BR blind-rotate-270 (1)
+.SH AUTHORS
+Mattias Andrée
+.RI < maandree@kth.se >
diff --git a/man/blind-multiply-matrices.1 b/man/blind-multiply-matrices.1
@@ -38,6 +38,7 @@ in reverse order.
.BR blind-matrix-shear (1),
.BR blind-matrix-translate (1),
.BR blind-matrix-transpose (1),
+.BR blind-invert-matrix (1),
.BR blind-transpose (1),
.BR blind-flip (1),
.BR blind-flop (1),
diff --git a/man/blind.7 b/man/blind.7
@@ -127,6 +127,9 @@ Framewise interleave videos
.BR blind-invert-luma (1)
Invert the luminosity of a video
.TP
+.BR blind-invert-matrix (1)
+Invert matrix-video
+.TP
.BR blind-linear-gradient (1)
Generate a video with a linear gradient
.TP
diff --git a/src/blind-invert-matrix.c b/src/blind-invert-matrix.c
@@ -0,0 +1,132 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+
+USAGE("")
+
+static int equal = 0;
+
+#define SUB_ROWS()\
+ do {\
+ p2 = matrix + r2 * cn;\
+ t = p2[r1][0];\
+ for (c = 0; c < cn; c++)\
+ p1[c][0] -= p2[c][0] * t;\
+ } while (0)
+
+#define PROCESS(TYPE)\
+ do {\
+ typedef TYPE pixel_t[4];\
+ size_t rn = stream->height, r1, r2, c;\
+ size_t cn = stream->width > rn ? stream->width : 2 * rn;\
+ pixel_t *matrix = buf, *p1, *p2 = NULL;\
+ TYPE t;\
+ \
+ for (r1 = 0; r1 < rn; r1++) {\
+ p1 = matrix + r1 * cn;\
+ if (!p1[r1][0]) {\
+ for (r2 = r1 + 1; r2 < rn; r2++) {\
+ p2 = matrix + r2 * cn;\
+ if (p2[r1][0])\
+ break;\
+ }\
+ if (r2 == rn)\
+ eprintf("matrix is not invertable\n");\
+ for (c = 0; c < cn; c++)\
+ t = p1[c][0], p1[c][0] = p2[c][0], p2[c][0] = t;\
+ }\
+ t = p1[r1][0];\
+ for (c = 0; c < cn; c++)\
+ p1[c][0] /= t;\
+ for (r2 = r1 + 1; r2 < rn; r2++)\
+ SUB_ROWS();\
+ }\
+ \
+ for (r1 = rn; r1--;) {\
+ p1 = matrix + r1 * cn;\
+ for (r2 = r1; r2--;)\
+ SUB_ROWS();\
+ }\
+ } while (0)
+
+static void process_lf(struct stream *stream, void *buf) { PROCESS(double); }
+static void process_f (struct stream *stream, void *buf) { PROCESS(float); }
+
+int
+main(int argc, char *argv[])
+{
+ struct stream stream;
+ size_t width, x, y, row_size, chan_size;
+ char *buf, *one = alloca(4 * sizeof(double)), *p;
+ void (*process)(struct stream *stream, void *buf);
+
+ ARGBEGIN {
+ case 'e':
+ equal = 1;
+ break;
+ default:
+ usage();
+ } ARGEND;
+
+ if (argc)
+ usage();
+
+ eopen_stream(&stream, NULL);
+ echeck_dimensions(&stream, WIDTH | HEIGHT, NULL);
+ width = stream.width;
+ if (stream.width < stream.height)
+ eprintf("<stdin>: the video must be at least as wide as it is tall\n");
+ else if (stream.width > stream.height)
+ stream.width -= stream.height;
+ fprint_stream_head(stdout, &stream);
+ stream.width = width;
+ efflush(stdout, "<stdout>");
+
+ if (!strcmp(stream.pixfmt, "xyza")) {
+ *(double *)one = 1;
+ process = process_lf;
+ } else if (!strcmp(stream.pixfmt, "xyza f")) {
+ *(float *)one = 1;
+ process = process_f;
+ } else {
+ eprintf("pixel format %s is not supported, try xyza\n", stream.pixfmt);
+ }
+
+ chan_size = stream.pixel_size / 4;
+ memcpy(one + 1 * chan_size, one, chan_size);
+ memcpy(one + 2 * chan_size, one, chan_size);
+ memcpy(one + 3 * chan_size, one, chan_size);
+
+ width = stream.width > stream.height ? stream.width : 2 * stream.height;
+ buf = emalloc2(width, stream.col_size);
+ row_size = width * stream.pixel_size;
+
+ while (eread_frame(&stream, buf)) {
+ if (stream.width == stream.height) {
+ for (y = stream.height; y--;) {
+ memmove(buf + y * row_size, buf + y * stream.row_size, stream.row_size);
+ memset(buf + y * row_size + stream.row_size, 0, stream.row_size);
+ memcpy(buf + y * row_size + y * stream.pixel_size, one, stream.pixel_size);
+ }
+ }
+ if (equal) {
+ process(&stream, buf + 1 * chan_size);
+ for (y = 0; y < stream.height; y++) {
+ for (x = 0; x < stream.width; x++) {
+ p = buf + y * row_size + x * stream.pixel_size;
+ memcpy(p + chan_size, p, chan_size);
+ memcpy(p + 2 * chan_size, p, 2 * chan_size);
+ }
+ }
+ } else {
+ process(&stream, buf + 0 * chan_size);
+ process(&stream, buf + 1 * chan_size);
+ process(&stream, buf + 2 * chan_size);
+ process(&stream, buf + 3 * chan_size);
+ }
+ for (y = 0; y < stream.height; y++)
+ ewriteall(STDOUT_FILENO, buf + y * row_size + stream.row_size, stream.row_size, "<stdout>");
+ }
+
+ free(buf);
+ return 0;
+}
