Snowbound Software’s RasterMaster for the .NET Platform includes the ability to change the horizontal or vertical resolution for file formats such as TIFF files. For example, if you have a file that is 240 x 120 and you want to change resolution to 240 x 240, you can use the C# code sample below to change the resolution.
status = simage.CIMG_decompress_bitmap_page(fileName,page);
sdibHeader = new CDIB_HEADER();
status = simage.CIMG_bitmap_info(sdibHeader);
// Or use status = simage.CIMGLOW_get_bitmap_header(sdibHeader);
//set XDPI
//sdibHeader.biXPelsPerMeter = 200;
//Set YDPI
sdibHeader.biYPelsPerMeter = 2*sdibHeader.biYPelsPerMeter;
status = simage.CIMGLOW_set_bitmap_header(sdibHeader);
status = simage.CIMG_resize_bitmap(240, 240);