protected override void CodeBitmapDirectly(IBitmap bm, int dw, int dy, int up2, int up1, int up0)
{
while (dy >= 0)
{
int context = GetDirectContext(bm, up2, up1, up0, 0);
for (int dx = 0; dx < dw;)
{
int n = CodeBit(false, _BitDist, context);
bm.SetByteAt(up0 + dx++, (sbyte)n);
context = ShiftDirectContext(bm, context, n, up2, up1, up0, dx);
}
up2 = up1;
up1 = up0;
up0 = bm.RowOffset(--dy);
}
}
protected override void CodeBitmapByCrossCoding(IBitmap bm, IBitmap cbm, int xd2c, int dw, int dy,
int cy, int up1, int up0, int xup1, int xup0,
int xdn1)
{
while (dy >= 0)
{
int context = GetCrossContext(bm, cbm, up1, up0, xup1, xup0, xdn1, 0);
for (int dx = 0; dx < dw;)
{
int n = CodeBit(false, _CBitDist, context);
bm.SetByteAt(up0 + dx++, (sbyte)n);
context = ShiftCrossContext(bm, cbm, context, n, up1, up0, xup1, xup0, xdn1, dx);
}
up1 = up0;
up0 = bm.RowOffset(--dy);
xup1 = xup0;
xup0 = xdn1;
xdn1 = cbm.RowOffset((--cy) - 1) + xd2c;
}
}