ref: 8188b4f4f0e07b6669e6ae3c6c1099af917eaab4
dir: /sys/src/cmd/jpg/gif.c/
#include <u.h>
#include <libc.h>
#include <bio.h>
#include <draw.h>
#include <event.h>
#include <keyboard.h>
#include "imagefile.h"
int cflag = 0;
int dflag = 0;
int eflag = 0;
int nineflag = 0;
int threeflag = 0;
int output = 0;
ulong outchan = CMAP8;
Image **allims;
int which;
int defaultcolor = 1;
enum{
Border = 2,
Edge = 5
};
char *show(int, char*);
Rectangle
imager(void)
{
Point p1, p2;
if(allims==nil || allims[0]==nil)
return screen->r;
p1 = addpt(divpt(subpt(allims[0]->r.max, allims[0]->r.min), 2), allims[0]->r.min);
p2 = addpt(divpt(subpt(screen->clipr.max, screen->clipr.min), 2), screen->clipr.min);
return rectaddpt(allims[0]->r, subpt(p2, p1));
}
void
eresized(int new)
{
Rectangle r;
if(new && getwindow(display, Refnone) < 0){
fprint(2, "gif: can't reattach to window\n");
exits("resize");
}
if(allims==nil || allims[which]==nil)
return;
r = imager();
border(screen, r, -Border, nil, ZP);
draw(screen, r, allims[which], nil, allims[which]->r.min);
flushimage(display, 1);
}
void
main(int argc, char *argv[])
{
int fd, i;
char *err;
ARGBEGIN{
case '3': /* produce encoded, compressed, three-color bitmap file; no display by default */
threeflag++;
/* fall through */
case 't': /* produce encoded, compressed, true-color bitmap file; no display by default */
cflag++;
dflag++;
output++;
defaultcolor = 0;
outchan = RGB24;
break;
case 'c': /* produce encoded, compressed, bitmap file; no display by default */
cflag++;
dflag++;
output++;
if(defaultcolor)
outchan = CMAP8;
break;
case 'd': /* suppress display of image */
dflag++;
break;
case 'e': /* disable floyd-steinberg error diffusion */
eflag++;
break;
case 'k': /* force black and white */
defaultcolor = 0;
outchan = GREY8;
break;
case 'v': /* force RGBV */
defaultcolor = 0;
outchan = CMAP8;
break;
case '9': /* produce plan 9, uncompressed, bitmap file; no display by default */
nineflag++;
dflag++;
output++;
if(defaultcolor)
outchan = CMAP8;
break;
default:
fprint(2, "usage: gif -39cdektv [file.gif ...]\n");
exits("usage");
}ARGEND;
err = nil;
if(argc == 0)
err = show(0, "<stdin>");
else{
for(i=0; i<argc; i++){
fd = open(argv[i], OREAD);
if(fd < 0){
fprint(2, "gif: can't open %s: %r\n", argv[i]);
err = "open";
}else{
err = show(fd, argv[i]);
close(fd);
}
if(output && argc>1 && err==nil){
fprint(2, "gif: exiting after one file\n");
break;
}
}
}
exits(err);
}
Image*
transparency(Rawimage *r, char *name)
{
Image *i;
int j, index;
uchar *pic, *mpic, *mask;
if((r->gifflags&TRANSP) == 0)
return nil;
i = allocimage(display, r->r, GREY8, 0, 0);
if(i == nil){
fprint(2, "gif: allocimage for mask of %s failed: %r\n", name);
return nil;
}
pic = r->chans[0];
mask = malloc(r->chanlen);
if(mask == nil){
fprint(2, "gif: malloc for mask of %s failed: %r\n", name);
freeimage(i);
return nil;
}
index = r->giftrindex;
mpic = mask;
for(j=0; j<r->chanlen; j++)
if(*pic++ == index)
*mpic++ = 0;
else
*mpic++ = 0xFF;
if(loadimage(i, i->r, mask, r->chanlen) < 0){
fprint(2, "gif: loadimage for mask of %s failed: %r\n", name);
free(mask);
freeimage(i);
return nil;
}
free(mask);
return i;
}
/* interleave alpha values of 0xFF in data stream. alpha value comes first, then b g r */
uchar*
expand(uchar *u, int chanlen, int nchan)
{
int j, k;
uchar *v, *up, *vp;
v = malloc(chanlen*(nchan+1));
if(v == nil){
fprint(2, "gif: malloc fails: %r\n");
exits("malloc");
}
up = u;
vp = v;
for(j=0; j<chanlen; j++){
*vp++ = 0xFF;
for(k=0; k<nchan; k++)
*vp++ = *up++;
}
return v;
}
void
addalpha(Rawimage *i)
{
char buf[32];
switch(outchan){
case CMAP8:
i->chans[0] = expand(i->chans[0], i->chanlen/1, 1);
i->chanlen = 2*(i->chanlen/1);
i->chandesc = CRGBVA16;
outchan = CHAN2(CMap, 8, CAlpha, 8);
break;
case GREY8:
i->chans[0] = expand(i->chans[0], i->chanlen/1, 1);
i->chanlen = 2*(i->chanlen/1);
i->chandesc = CYA16;
outchan = CHAN2(CGrey, 8, CAlpha, 8);
break;
case RGB24:
i->chans[0] = expand(i->chans[0], i->chanlen/3, 3);
i->chanlen = 4*(i->chanlen/3);
i->chandesc = CRGBA32;
outchan = RGBA32;
break;
default:
chantostr(buf, outchan);
fprint(2, "gif: can't add alpha to type %s\n", buf);
exits("err");
}
}
/*
* Called only when writing output. If the output is RGBA32,
* we must write four bytes per pixel instead of two.
* There's always at least two: data plus alpha.
* r is used only for reference; the image is already in c.
*/
void
blackout(Rawimage *r, Rawimage *c)
{
int i, trindex;
uchar *rp, *cp;
rp = r->chans[0];
cp = c->chans[0];
trindex = r->giftrindex;
if(outchan == RGBA32)
for(i=0; i<r->chanlen; i++){
if(*rp == trindex){
*cp++ = 0x00;
*cp++ = 0x00;
*cp++ = 0x00;
*cp++ = 0x00;
}else{
*cp++ = 0xFF;
cp += 3;
}
rp++;
}
else
for(i=0; i<r->chanlen; i++){
if(*rp == trindex){
*cp++ = 0x00;
*cp++ = 0x00;
}else{
*cp++ = 0xFF;
cp++;
}
rp++;
}
}
int
init(void)
{
static int inited;
if(inited == 0){
if(initdraw(0, 0, 0) < 0){
fprint(2, "gif: initdraw failed: %r\n");
return -1;
}
einit(Ekeyboard|Emouse);
inited++;
}
return 1;
}
char*
show(int fd, char *name)
{
Rawimage **images, **rgbv;
Image *tmp, *msk, *img, *dst, **ims;
Rectangle r;
int j, k, n, ch, nloop, loopcount, dt;
char *err;
char buf[32];
err = nil;
images = readgif(fd, CRGB, dflag);
if(images == nil){
fprint(2, "gif: decode %s failed: %r\n", name);
return "decode";
}
for(n=0; images[n]; n++)
if(n == 0)
r = images[n]->r;
else
combinerect(&r, images[n]->r);
tmp = nil;
ims = malloc((n+1)*sizeof(Image*));
rgbv = malloc((n+1)*sizeof(Rawimage*));
if(rgbv==nil || ims==nil){
fprint(2, "gif: malloc of masks for %s failed: %r\n", name);
err = "malloc";
goto Return;
}
memset(ims, 0, (n+1)*sizeof(Image*));
memset(rgbv, 0, (n+1)*sizeof(Rawimage*));
if(!dflag){
if(init() < 0){
err = "initdraw";
goto Return;
}
if(defaultcolor && screen->depth>8)
outchan = RGB24;
}
for(k=0; k<n; k++){
if(outchan == CMAP8)
rgbv[k] = torgbv(images[k], !eflag);
else{
if(outchan==GREY8 || (images[k]->chandesc==CY && threeflag==0))
rgbv[k] = totruecolor(images[k], CY);
else
rgbv[k] = totruecolor(images[k], CRGB24);
}
if(rgbv[k] == nil){
fprint(2, "gif: converting %s to local format failed: %r\n", name);
err = "torgbv";
goto Return;
}
if(!dflag){
msk = transparency(images[k], name);
if(rgbv[k]->chandesc == CY)
img = allocimage(display, rgbv[k]->r, GREY8, 0, 0);
else
img = allocimage(display, rgbv[k]->r, outchan, 0, 0);
if(tmp == nil)
tmp = allocimage(display, r, img->chan, 0, DWhite);
ims[k]= dst = allocimage(display, r, tmp->chan, 0, DWhite);
if(tmp == nil || img == nil || dst == nil){
fprint(2, "gif: allocimage %s failed: %r\n", name);
err = "allocimage";
goto Return;
}
if(loadimage(img, img->r, rgbv[k]->chans[0], rgbv[k]->chanlen) < 0){
fprint(2, "gif: loadimage %s failed: %r\n", name);
err = "loadimage";
goto Return;
}
switch((images[k]->gifflags>>2)&7){
default:
draw(tmp, img->r, img, msk, img->r.min);
draw(dst, tmp->r, tmp, nil, tmp->r.min);
break;
case 2:
draw(tmp, img->r, display->white, msk, img->r.min);
/* no break */
case 3:
draw(dst, tmp->r, tmp, nil, tmp->r.min);
draw(dst, img->r, img, msk, img->r.min);
break;
}
freeimage(msk);
freeimage(img);
}
}
if(tmp)
freeimage(tmp);
allims = ims;
loopcount = images[0]->gifloopcount;
if(!dflag){
nloop = 0;
do{
for(k=0; k<n; k++){
which = k;
eresized(0);
dt = images[k]->gifdelay*10;
if(dt < 50)
dt = 50;
while(n==1 || ecankbd()){
/* an odd, democratic list */
if((ch=ekbd())=='q' || ch==Kdel || ch==Keof)
exits(nil);
if(ch == '\n')
goto Out;
}sleep(dt);
}
/* loopcount -1 means no loop (this code's rule), loopcount 0 means loop forever (netscape's rule)*/
}while(loopcount==0 || ++nloop<loopcount);
/* loop count has run out */
ekbd();
Out:
draw(screen, screen->clipr, display->white, nil, ZP);
}
if(nineflag){
if(images[0]->gifflags&TRANSP){
addalpha(rgbv[0]);
blackout(images[0], rgbv[0]);
}
chantostr(buf, outchan);
print("%11s %11d %11d %11d %11d ", buf,
rgbv[0]->r.min.x, rgbv[0]->r.min.y, rgbv[0]->r.max.x, rgbv[0]->r.max.y);
if(write(1, rgbv[0]->chans[0], rgbv[0]->chanlen) != rgbv[0]->chanlen){
fprint(2, "gif: %s: write error %r\n", name);
return "write";
}
}else if(cflag){
if(images[0]->gifflags&TRANSP){
addalpha(rgbv[0]);
blackout(images[0], rgbv[0]);
}
if(writerawimage(1, rgbv[0]) < 0){
fprint(2, "gif: %s: write error: %r\n", name);
return "write";
}
}
Return:
allims = nil;
for(k=0; images[k]; k++){
for(j=0; j<images[k]->nchans; j++)
free(images[k]->chans[j]);
free(images[k]->cmap);
if(rgbv[k])
free(rgbv[k]->chans[0]);
freeimage(ims[k]);
free(images[k]);
free(rgbv[k]);
}
free(images);
free(ims);
return err;
}