| 主权项 |
1. A portable electronic device for performing image cropping manipulation, comprising:
a touch screen configured to display a sub-image and to provide a user interface for receiving at least one user input, the sub-image is cropped from a digital image; and an image processing unit, configured to perform an operation corresponding to the user input, the image processing unit comprises:
a space mapping module, configured to map the sub-image to an image space and map the user input to the operation in the image space; andan image cropping module, configured to perform the operation and update the sub-image according to the user input; wherein the space mapping module is further configured to define the image space corresponding to the digital image and a cropping space corresponding to the sub-image, and is configured to map the user input from the cropping space to the image space for adjusting a sub-region in the image space, and the sub-region is corresponding to the sub-image and is defined according to a plurality of control points; wherein the user input is converted to an input vector in the cropping space and mapped to an output vector with respect to at least one control point in the image space, and the input vector is in relative opposite direction to the output vector; and wherein the space mapping module decomposes the input vector to at least two perpendicular principal vectors in the cropping space, decomposes the output vector to at least two principal vectors in the image space and maps the input vector to the output vector according to a first angle and a second angle wherein the first angle is between the in out vector and one of the perpendicular principal vectors of the input vector, and the second angle is between the output vector and one of the principal vectors of the output vector. |
