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/* See LICENSE file for copyright and license details. */
#include "common.h"
USAGE("[-c]")
static int per_channel = 0;
#define PROCESS(TYPE)\
do {\
typedef TYPE pixel_t[4];\
pixel_t matrix[9];\
pixel_t buf[2];\
TYPE x2, y2, norm2;\
size_t i;\
\
for (i = 0; i < stream->n_chan; i++) {\
matrix[0][i] = 1, matrix[1][i] = 0, matrix[2][i] = 0;\
matrix[3][i] = 0, matrix[4][i] = 1, matrix[5][i] = 0;\
matrix[6][i] = 0, matrix[7][i] = 0, matrix[8][i] = 1;\
}\
\
while (eread_frame(stream, buf)) {\
if (per_channel) {\
for (i = 0; i < stream->n_chan; i++) {\
x2 = buf[0][i] * buf[0][i];\
y2 = buf[1][i] * buf[1][i];\
norm2 = x2 + y2;\
matrix[0][i] = x2 / norm2;\
matrix[4][i] = y2 / norm2;\
matrix[3][i] = matrix[1][i] = buf[0][i] * buf[1][i] / norm2;\
}\
} else {\
buf[0][1] *= buf[0][3];\
buf[1][1] *= buf[1][3];\
x2 = buf[0][1] * buf[0][1];\
y2 = buf[1][1] * buf[1][1];\
norm2 = x2 + y2;\
matrix[0][0] = x2 / norm2;\
matrix[4][0] = y2 / norm2;\
matrix[3][0] = matrix[1][0] = buf[0][1] * buf[1][1] / norm2;\
for (i = 1; i < stream->n_chan; i++) {\
matrix[0][i] = matrix[0][0];\
matrix[1][i] = matrix[1][0];\
matrix[3][i] = matrix[3][0];\
matrix[4][i] = matrix[4][0];\
}\
}\
ewriteall(STDOUT_FILENO, matrix, sizeof(matrix), "<stdout>");\
}\
} while (0)
static void process_lf(struct stream *stream) { PROCESS(double); }
static void process_f(struct stream *stream) { PROCESS(float); }
int
main(int argc, char *argv[])
{
struct stream stream;
void (*process)(struct stream *stream);
ARGBEGIN {
case 'c':
per_channel = 1;
break;
default:
usage();
} ARGEND;
if (argc)
usage();
eopen_stream(&stream, NULL);
if (stream.width > 2 || stream.height > 2 || stream.width * stream.height != 2)
eprintf("<stdin>: each frame must contain exactly 2 pixels\n");
stream.width = 3;
stream.height = 3;
fprint_stream_head(stdout, &stream);
efflush(stdout, "<stdout>");
if (stream.encoding == DOUBLE)
process = process_lf;
else if (stream.encoding == FLOAT)
process = process_f;
else
eprintf("pixel format %s is not supported, try xyza\n", stream.pixfmt);
process(&stream);
return 0;
}
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