#include <u.h>#include <libc.h>#include <draw.h> int main(int argc, char **argv){	Image *src, *dst;	ulong chan; 	if(argc == 2){		chan = strtochan(argv[1]);	}else{		chan = GREY1;	} 	if(initdraw(nil, nil, "convert") == -1){		fprint(2, "initdraw: %r\n");		return 1;	} 	src = readimage(display, 0, 0);	if(!src){		fprint(2, "readimage: %r\n");		return 1;	} 	dst = allocimage(display, src->r, chan, 0, DNofill);	if(!dst){		fprint(2, "allocimage: %r\n");		return 1;	} 	draw(dst, src->r, src, nil, src->r.min); 	if(writeimage(1, dst, 0) == -1){		fprint(2, "writeimage: %r\n");		return 1;	} 	freeimage(src);	freeimage(dst); 	closedisplay(display); 	return 0;}