void
JB2Dict::JB2Codec::code_bitmap_by_cross_coding (GBitmap &bm, GP<GBitmap> &cbm, const int libno)
{
// Make sure bitmaps will not be disturbed
GP<GBitmap> copycbm=GBitmap::create();
if (cbm->monitor())
{
// Perform a copy when the bitmap is explicitely shared
GMonitorLock lock2(cbm->monitor());
copycbm->init(*cbm);
cbm = copycbm;
}
GMonitorLock lock1(bm.monitor());
// Center bitmaps
const int cw = cbm->columns();
const int dw = bm.columns();
const int dh = bm.rows();
const LibRect &l = libinfo[libno];
const int xd2c = (dw/2 - dw + 1) - ((l.right - l.left + 1)/2 - l.right);
const int yd2c = (dh/2 - dh + 1) - ((l.top - l.bottom + 1)/2 - l.top);
// Ensure borders are adequate
bm.minborder(2);
cbm->minborder(2-xd2c);
cbm->minborder(2+dw+xd2c-cw);
// Initialize row pointers
const int dy = dh - 1;
const int cy = dy + yd2c;
#ifndef NDEBUG
bm.check_border();
cbm->check_border();
#endif
code_bitmap_by_cross_coding (bm,*cbm, xd2c, dw, dy, cy, bm[dy+1], bm[dy],
(*cbm)[cy+1] + xd2c, (*cbm)[cy ] + xd2c, (*cbm)[cy-1] + xd2c);
}
void
JB2Dict::JB2Codec::Decode::code_bitmap_by_cross_coding (GBitmap &bm, GBitmap &cbm,
const int xd2c, const int dw, int dy, int cy,
unsigned char *up1, unsigned char *up0, unsigned char *xup1,
unsigned char *xup0, unsigned char *xdn1 )
{
ZPCodec &zp=*gzp;
// iterate on rows (decoding)
while (dy >= 0)
{
int context=get_cross_context(
up1, up0, xup1, xup0, xdn1, 0);
for(int dx=0;dx < dw;)
{
const int n = zp.decoder(cbitdist[context]);
up0[dx++] = n;
context=shift_cross_context(context, n,
up1, up0, xup1, xup0, xdn1, dx);
}
// next row
up1 = up0;
up0 = bm[--dy];
xup1 = xup0;
xup0 = xdn1;
xdn1 = cbm[(--cy)-1] + xd2c;
#ifndef NDEBUG
bm.check_border();
#endif
}
}
void
JB2Dict::JB2Codec::Decode::code_bitmap_directly(
GBitmap &bm,const int dw, int dy,
unsigned char *up2, unsigned char *up1, unsigned char *up0 )
{
ZPCodec &zp=*gzp;
// iterate on rows (decoding)
while (dy >= 0)
{
int context=get_direct_context(up2, up1, up0, 0);
for(int dx=0;dx < dw;)
{
int n = zp.decoder(bitdist[context]);
up0[dx++] = n;
context=shift_direct_context(context, n, up2, up1, up0, dx);
}
// next row
dy -= 1;
up2 = up1;
up1 = up0;
up0 = bm[dy];
}
#ifndef NDEBUG
bm.check_border();
#endif
}
