When i open black and white bitmap , it's color is inverted. It's bug?

I found a problem in your viewer.

When I open a black and white bitmap image, black and white are

Can you tell me what's wrong.

I assume that you are embedding a bitmap in a PDF similar to AddImage
sample (http://www.pdftron.com/pdfnet/samplecode.html#AddImage). What
is the type of the image you are embedding? In case of TIFF some apps
(such as Windows Picture Viewer) do not properly interpret some fields
which define which pixel is white/black. You could invert pixels in a
gray-scale image in PDF as follows:

pdftrom.PDF.Image img = ...
Obj dec = img.GetSDFObj().PutArray("Decode");
// Swap the following two lines to invert the image