The following are routines for modifying the coordinate system and generally warping an image.
Imrect *im_subim(Imrect * image, Imregion * region)Returns an image which is a new copy of specified roi of image.
void im_shift(Imrect * im, int dy, int dx)Returns an image which is a shifted copy the specified image shifted by the amounts specified in the given parameters.
Imrect *im_bshift(Imrect *im, int y , int x)Returns an image which is a barrel shifted copy the specified image shifted by the amounts specified in the given parameters. The returned image maintains the original co-ordinates of the input image.
Imrect *im_rectify(Imrect * im1, Mat3 rect)Returns a new image created by the specified perspective transform of the input image.
Imrect *im_warp(Imrect * im1, Vec2(*f) ( /* ??? */ ), void *data)This is the generic image warping routine which applies the inverse warp function specified in order to create the warped output image.