Image resizing plays an important role in image processing and the corresponding methods are widely used in various kinds of image processing software. Recently

oblique projection based B-Spline image resizing has been developed. Compared to conventional image resizing methods such as the nearest neighbor interpolation

bilinear interpolation

and bicubic spline interpolation

this method performs better. The resized image using oblique projection method has more continuity than using other methods.For the same reason

the resized image is smoothed at the same time

especially at the places where exist sharp edges. Thus

some important information lying in the area is lost. This result is unexpected in image processing. In this paper

a sharpness preserving method in the procedure of image resizing is proposed in order to overcome the shortcoming of oblique projection B-Spline image resizing mentioned above.In the new method

the range of integral of an output pixel is changed when there are sharp edges including in the corresponding source pixels

thus the sharpness of the output pixel can be preserved. Results show that the method performs better in both continuity and sharpness preserving.