#include <vips/vips.h>
#include <stdio.h>

int main() {
        VipsImage* in, *thm, *pre, *out;

        VIPS_INIT("test app");

        // load input png
        vips_pngload("test.png",
                &in,
                NULL);

        // resize image
        vips_premultiply(in, &pre, NULL);
        vips_resize(pre, &thm, 0.5, NULL);
        vips_unpremultiply(thm, &out, NULL);

        // save as JPEG XL
        vips_jxlsave(out, "out.jxl", NULL);
        puts(vips_error_buffer());

        vips_shutdown();
        return 0;
}