Image processing method and computer readable medium
An image processing method is provided capable of improving a response to a user in a case where a series of images using volume data are displayed by volume rendering. When the images are displayed by animation in an oscillating manner with amplitude, the amplitude is gradually increased so as to spare time for image generation. That is, when the user specifies a parameter value, for example, a projection angle (initial value: θ=0°), for an object to be diagnosed, animation display of images C, D, and E of the object is performed with a small amplitude (θ=±5°) with the initial value as a center. During the animation display, an image B (θ=−10°) and an image F (θ=10°) are calculated in the background. After the calculation is completed, the amplitude is increased (θ=±10°) and animation display of the images B, C, D, E, and F is performed.
1. An image processing method comprising:
setting a reference value of a parameter value for displaying an image;
sequentially displaying the image with the parameter value;
oscillating the parameter value around the reference value based on an amplitude of oscillation; and
sequentially displaying the image corresponding to the parameter value, the image being generated by volume rendering using volume data that is specified by the parameter value,
gradually increasing the amplitude of oscillation over a period of time so that a peak-to-peak amplitude of resulting oscillations gradually increases over time.
2. The image processing method as claimed in claim 1 , wherein when an image corresponding to a changed parameter value is stored in a storage, the stored image is displayed, and
when the image corresponding to the changed parameter value is not stored in the storage, the image corresponding to the changed parameter value is generated during an interval in which a plurality of stored images are sequentially displayed, and then displayed and stored in the storage after said interval.
3. The image-processing method as claimed in claim 1 , wherein a plurality of variables depends on the parameter value.
4. The image processing method as claimed in claim 3 , wherein the parameter value is a projection angle of a virtual ray in the volume rendering.
5. The image processing method as claimed in claim 3 , wherein the parameter value is a projection position from which a virtual ray is projected in the volume rendering.
6. The image processing method as claimed in claim 5 , wherein the projection position is a view point that moves along on a set path.
7. The image processing method as claimed in claim 3 , wherein the parameter value determines an opacity function in ray casting method.
8. The image processing method as claimed in claim 3 , wherein the parameter value determines a color LUT (Look-Up Table) function in ray casting method.
9. The image processing method as claimed in claim 1 , wherein the parameter value determines at least one of a window width value and a window level value being used for an image calculation in MIP (Maximum Intensity Projection) method, MinIP (Minimum Intensity Projection) method, raysum method, or average value method.
10. The image processing method as claimed in claim 1 , wherein the parameter value is a combining ratio of a fusion image.
11. The image processing method as claimed in claim 2 , wherein while the stored image is displayed, the next image to be created is generated and stored in advance, said next image corresponding to an increased amplitude of oscillation.
12. The image processing method as claimed in claim 1 , wherein a plurality of the images is generated in parallel based on the respective parameter values.
13. The image processing method as claimed in claim 1 , wherein the reference value is set by a user.
14. The image processing method as claimed in claim 1 , wherein the image generation is stopped by an instruction from a user.
15. A computer readable medium having a program including instructions for permitting a computer to perform image processing, said instructions comprising:
setting a reference value of a parameter value for displaying an image;
sequentially displaying the image with the parameter value;
oscillating the parameter value around the reference value based on an amplitude of oscillation; and
sequentially displaying the image corresponding to the parameter value, the image being generated by volume rendering using volume data that is specified by the parameter value,
gradually increasing the amplitude of oscillation over a period of time so that a peak-to-peak amplitude of resulting oscillations gradually increases over time.