static void do_decode_24bit(deark *c, lctx *d, struct page_ctx *pg)
{
dbuf *unc_pixels = NULL;
struct deark_bitmap *img = NULL;
de_int64 i, j;
de_byte cr, cg, cb, ca;
de_int64 w, h;
de_int64 skip;
w = pg->type_info->width;
h = pg->type_info->height;
// TODO: Try to support uncompressed 24-bit images, assuming they exist.
// Apparently, some 'it32' icons begin with four extra 0x00 bytes.
// Skip over the first four bytes if they are 0x00.
// (I don't know the reason for these bytes, but this is the same
// logic libicns uses.)
skip = 0;
if(pg->code4cc.id==0x69743332) { // 'it32' (128x128)
if(!dbuf_memcmp(c->infile, pg->image_pos, "\0\0\0\0", 4)) {
skip = 4;
}
}
unc_pixels = dbuf_create_membuf(c, w*h*3, 1);
do_uncompress_24(c, d, pg, unc_pixels, skip);
img = de_bitmap_create(c, w, h, 4);
for(j=0; j<pg->type_info->height; j++) {
for(i=0; i<pg->type_info->width; i++) {
cr = dbuf_getbyte(unc_pixels, j*w + i);
cg = dbuf_getbyte(unc_pixels, (h+j)*w + i);
cb = dbuf_getbyte(unc_pixels, (2*h+j)*w + i);
if(pg->mask_pos)
ca = de_getbyte(pg->mask_pos + j*w + i);
else
ca = 0xff;
de_bitmap_setpixel_rgba(img, i, j, DE_MAKE_RGBA(cr,cg,cb,ca));
}
}
de_bitmap_write_to_file(img, pg->filename_token, 0);
de_bitmap_destroy(img);
if(unc_pixels) dbuf_close(unc_pixels);
}
static void do_image_16_32bit(deark *c, lctx *d, dbuf *bits, de_int64 bits_offset)
{
struct deark_bitmap *img = NULL;
de_int64 i, j;
int has_transparency;
de_uint32 v;
de_int64 k;
de_byte sm[4];
if(d->bitfields_type==BF_SEGMENT) {
has_transparency = (d->bitfields_segment_len>=16 && d->bitfield[3].mask!=0);
}
else if(d->bitfields_type==BF_IN_HEADER) {
has_transparency = (d->bitfield[3].mask!=0);
}
else {
has_transparency = 0;
}
img = bmp_bitmap_create(c, d, has_transparency?4:3);
for(j=0; j<d->height; j++) {
for(i=0; i<d->width; i++) {
if(d->bitcount==16) {
v = (de_uint32)dbuf_getui16le(bits, bits_offset + j*d->rowspan + 2*i);
}
else {
v = (de_uint32)dbuf_getui32le(bits, bits_offset + j*d->rowspan + 4*i);
}
for(k=0; k<4; k++) {
if(d->bitfield[k].mask!=0) {
sm[k] = (de_byte)(0.5 + d->bitfield[k].scale * (double)((v&d->bitfield[k].mask) >> d->bitfield[k].shift));
}
else {
if(k==3)
sm[k] = 255; // Default alpha sample = opaque
else
sm[k] = 0; // Default other samples = 0
}
}
de_bitmap_setpixel_rgba(img, i, j, DE_MAKE_RGBA(sm[0], sm[1], sm[2], sm[3]));
}
