ref: 172dc0005aa16dea8451bf2bcef7f3eb04df2c04
dir: /sys/src/cmd/jpg/totif.c/
#include <u.h> #include <libc.h> #include <bio.h> #include <draw.h> #include <memdraw.h> #include "imagefile.h" static Memimage *memtochan(Memimage *, ulong); void usage(void) { fprint(2, "usage: %s [-c 'comment'] " "[-3bgGhklLptvyY] [file]\n", argv0); exits("usage"); } void main(int argc, char *argv[]) { Biobuf bout; Memimage *i, *ni; int fd, chanflag, comp, opt; char *err, *file, *c; ulong chan; chan = BGR24; chanflag = opt = 0; comp = 1; c = nil; ARGBEGIN { case '3': /* force RGB */ chan = BGR24; chanflag = 1; break; case 'b': chan = GREY1; chanflag = 1; break; case 'c': c = EARGF(usage()); break; case 'g': /* t4 */ comp = 3; opt = 0; break; case 'G': /* t4 two-dimensional */ comp = 3; opt = 1; break; case 'h': /* huffman */ comp = 2; break; case 'k': chan = GREY8; chanflag = 1; break; case 'l': /* lzw */ comp = 5; opt = 0; break; case 'L': /* lzw, horizontal differencing */ comp = 5; opt = 1; break; case 'p': /* packbits */ comp = 0x8005; break; case 't': /* t6 */ comp = 4; break; case 'v': /* RGBV */ chan = CMAP8; chanflag = 1; break; case 'y': chan = GREY2; chanflag = 1; break; case 'Y': chan = GREY4; chanflag = 1; break; default: usage(); } ARGEND if(argc > 1) usage(); if(argc == 0) { file = "<stdin>"; fd = 0; } else { file = argv[0]; if((fd = open(file, OREAD)) < 0) sysfatal("open %s: %r", file); } if(Binit(&bout, 1, OWRITE) < 0) sysfatal("Binit: %r"); memimageinit(); if((i = readmemimage(fd)) == nil) sysfatal("readmemimage %s: %r", file); close(fd); if(comp >= 2 && comp <= 4) { chan = GREY1; chanflag = 1; } else if(chan == GREY2) { if((ni = memtochan(i, chan)) == nil) sysfatal("memtochan: %r"); if(i != ni) { freememimage(i); i = ni; } chan = GREY4; } if(!chanflag) { switch(i->chan) { case GREY1: case GREY4: case GREY8: case CMAP8: case BGR24: break; case GREY2: chan = GREY4; chanflag = 1; break; default: chanflag = 1; break; } } if(chanflag) { if((ni = memtochan(i, chan)) == nil) sysfatal("memtochan: %r"); if(i != ni) { freememimage(i); i = ni; } } if((err = memwritetif(&bout, i, c, comp, opt)) != nil) fprint(2, "%s: %s\n", argv0, err); freememimage(i); exits(err); } static Memimage * memtochan(Memimage *i, ulong chan) { Memimage *ni; if(i->chan == chan) return i; if((ni = allocmemimage(i->r, chan)) == nil) return nil; memimagedraw(ni, ni->r, i, i->r.min, nil, i->r.min, S); return ni; }