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/* See LICENSE file for copyright and license details. */
#include "arg.h"
#include "stream.h"
#include "util.h"
#include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
static int luma_warning_triggered = 0;
static int gamut_warning_triggered = 0;
static int alpha_warning_triggered = 0;
static void
usage(void)
{
eprintf("usage: %s [-d depth]\n", argv0);
}
static void
write_pixel(double R, double G, double B, double A, int bytes, unsigned long long int max)
{
unsigned long long int colours[4];
unsigned char buf[4 * 8];
int i, j, k, bm = bytes - 1;
size_t ptr, n;
ssize_t r;
if (R < 0 || G < 0 || B < 0 || R > 1 || G > 1 || B > 1) {
if (gamut_warning_triggered) {
gamut_warning_triggered = 1;
weprintf("warning: out-of-gamut colour detected\n");
}
; /* TODO gamut */
R = R < 0 ? 0 : R > 1 ? 1 : R;
G = G < 0 ? 0 : G > 1 ? 1 : G;
B = B < 0 ? 0 : B > 1 ? 1 : B;
}
if (A < 0 || A > 1) {
if (alpha_warning_triggered) {
alpha_warning_triggered = 1;
weprintf("warning: alpha values truncated\n");
}
A = A < 0 ? 0 : 1;
}
colours[0] = srgb_encode(R) * max + 0.5;
colours[1] = srgb_encode(G) * max + 0.5;
colours[2] = srgb_encode(B) * max + 0.5;
colours[3] = A * max + 0.5;
for (i = k = 0; i < 4; i++) {
for (j = 0; j < bytes; j++, k++) {
buf[k + bm - j] = (unsigned char)(colours[j]);
colours[j] >>= 8;
}
}
n = (size_t)bytes * 4;
for (ptr = 0; ptr < n; ptr += (size_t)r) {
r = write(STDOUT_FILENO, buf + ptr, n - ptr);
if (r < 0)
eprintf("write <stdout>:");
}
}
static void
process_xyza(struct stream *stream, size_t n, int bytes, unsigned long long int max)
{
size_t i;
double X, Y, Z, A, R, G, B;
for (i = 0; i < n; i += stream->pixel_size) {
X = ((double *)(stream->buf + i))[0];
Y = ((double *)(stream->buf + i))[1];
Z = ((double *)(stream->buf + i))[2];
A = ((double *)(stream->buf + i))[3];
if (Y < 0 || Y > 1) {
if (luma_warning_triggered) {
luma_warning_triggered = 1;
weprintf("warning: %s colour detected\n",
Y < 0 ? "subblack" : "superwhite");
}
}
srgb_to_ciexyz(X, Y, Z, &R, &G, &B);
write_pixel(R, G, B, A, bytes, max);
}
}
int
main(int argc, char *argv[])
{
struct stream stream;
int depth = 16, bytes;
unsigned long long int max;
size_t n;
void (*process)(struct stream *stream, size_t n, int bytes, unsigned long long int max);
ARGBEGIN {
case 'd':
if (toi(EARGF(usage()), 1, 64, &depth))
eprintf("argument of -d must be an integer in [1, 64]\n");
break;
default:
usage();
} ARGEND;
if (argc)
usage();
stream.fd = STDIN_FILENO;
stream.file = "<stdin.h>";
einit_stream(&stream);
max = 1ULL << (depth - 1);
max |= max - 1;
for (bytes = 1; bytes * 8 < depth; bytes++);
if (!strcmp(stream.pixfmt, "xyza"))
process = process_xyza;
else
eprintf("pixel format %s is not supported, try xyza\n", stream.pixfmt);
printf("P7\n"
"WIDTH %zu\n"
"HEIGHT %zu\n"
"DEPTH 4\n" /* Depth actually means channels */
"MAXVAL %llu\n"
"TUPLTYPE RGB_ALPHA\n"
"ENDHDR\n", stream.width, stream.height, max);
fflush(stdout);
if (ferror(stdout))
eprintf("<stdout>:");
for (;;) {
n = stream.ptr;
n -= n % stream.pixel_size;
process(&stream, n, bytes, max);
memmove(stream.buf, stream.buf + n, stream.ptr -= n);
if (!eread_stream(&stream, SIZE_MAX))
break;
}
return 0;
}
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