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/* See LICENSE file for copyright and license details. */
#include "common.h"
USAGE("[-r]")
static size_t fm;
static double fm_double;
static float fm_float;
static int reverse = 0;
#define PROCESS(TYPE)\
do {\
size_t i = stream->alpha_chan * stream->chan_size;\
TYPE a = fm ? (TYPE)(reverse ? f : fm - f) / fm_##TYPE : (TYPE)0.5;\
for (; i < n; i += stream->pixel_size)\
*(TYPE *)(stream->buf + i) *= a;\
} while (0)
static void process_lf(struct stream *stream, size_t n, size_t f) {PROCESS(double);}
static void process_f (struct stream *stream, size_t n, size_t f) {PROCESS(float);}
int
main(int argc, char *argv[])
{
struct stream stream;
void (*process)(struct stream *stream, size_t n, size_t f);
ARGBEGIN {
case 'r':
reverse = 1;
break;
default:
usage();
} ARGEND;
if (argc)
usage();
eopen_stream(&stream, NULL);
SELECT_PROCESS_FUNCTION(&stream);
CHECK_CHANS(&stream, != -1, == stream.luma_chan);
if (!stream.frames)
eprintf("video's length is not recorded");
fprint_stream_head(stdout, &stream);
efflush(stdout, "<stdout>");
fm_double = (double)(fm = stream.frames - 1);
fm_float = (float)fm_double;
process_each_frame_segmented(&stream, STDOUT_FILENO, "<stdout>", process);
return 0;
}
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