removed 'const int small_const = 0.001' in src/image_util.c as it was resulting in compile warnings: implicit conversion from 'double' to 'int' changes value from 0.001 to 0. This small_const was subtracted to sp_image_x(img) and img->detector->image_center[i] to deal with numerical errors when integers are represented as floats, but since the mantissa includes 23 bits in 32-bit float, it means that it can represent integer numbers exactly up to 2^22 = 4194304 (using one bit for sign), so this is in reality never a problem for the dimensions nor the image center.