Image processing apparatus and method for image resizing matching data supply speed

• US 20070071360A1
• Filed: 09/14/2006
• Published: 03/29/2007
• Est. Priority Date: 09/15/2005
• Status: Active Grant

• Current Assignee: Cypress Semiconductor Corporation (Infineon Technologies AG)
• Original Assignee: Fujitsu Limited
• Inventors: Kudo, Toshio, Kuroki, Kenichiro
• Granted Patent: US 8,630,511 B2
• Time in Patent Office: Days
• US Class Current: 382/298
• CPC Class Codes: G06T 3/4007 based on interpolation, e.g. bilinear interpolation image demosaicing G06T3/4015; edge-driven or edge-based scaling G06T3/403
• CPC Class Codes: H04N 1/3875 combined with enlarging or reducing enlarging or reducing per se H04N1/393

Abstract

An image processing apparatus includes a data supply node to receive line data scanned in a main scan direction of an image, an image enlargement unit coupled to the data supply node to apply to the line data an enlargement process for enlarging the image by an enlargement factor equal to an integer so as to produce enlarged data at an output node, and an image reduction unit coupled to the output node of the image enlargement unit to apply to the enlarged data a reduction process for reducing the enlarged image by a desired reduction factor so as to produce reduced data at an output node.

Claims

1. An image processing apparatus, comprising:

a data supply node to receive line data scanned in a main scan direction of an image;

an image enlargement unit coupled to the data supply node to apply to the line data an enlargement process for enlarging the image by an enlargement factor equal to an integer so as to produce enlarged data at an output node; and

an image reduction unit coupled to the output node of the image enlargement unit to apply to the enlarged data a reduction process for reducing the enlarged image by a desired reduction factor so as to produce reduced data at an output node.

2. The image processing apparatus as claimed in claim 1, further comprising:

an image sensor to output image data to an output node; and

an image cutout unit coupled between the output node of the image sensor and the data supply node to supply, as said line data to the data supply node, data corresponding to a portion cut out of the image data.

3. The image processing apparatus as claimed in claim 2, further comprising:

a system bus coupled to the output node of the image reduction unit; and

a frame memory coupled to the system bus to store the reduced data.

4. The image processing apparatus as claimed in claim 2, wherein the image enlargement unit is coupled to the output node of the image cutout unit without having an intervening frame memory.

5. The image processing apparatus as claimed in claim 1, wherein the enlargement factor of the enlargement process performed by the image enlargement unit is at least one fixed magnification factor, and the reduction factor of the reduction process performed by the image reduction unit is a freely settable magnification factor.

6. The image processing apparatus as claimed in claim 1, wherein the enlargement process performed by the image enlargement unit is enlargement based on nearest neighbor interpolation, and wherein the image reduction unit includes a filtering unit configured to apply low-pass filtering to the enlarged data.

7. The image processing apparatus as claimed in claim 6, wherein the reduction process performed by the image reduction unit is reduction based on bilinear interpolation or bicubic interpolation.

8. The image processing apparatus as claimed in claim 1, wherein the image reduction unit is coupled to the output node of the image enlargement unit without having an intervening frame memory.

9. The image processing apparatus as claimed in claim 1, further comprising a horizontal reduction unit configured to receive image data as an input and to supply, as the line data to the data supply node, data obtained by applying a horizontal reduction process for reducing the image data in a horizontal direction.

10. The image processing apparatus as claimed in claim 9, wherein the image enlargement unit is configured to enlarge the image by copying each pixel value by use of a nearest neighbor method.

11. The image processing apparatus as claimed in claim 9, wherein the horizontal reduction unit is configured to perform the horizontal reduction process through sub-sampling that takes an average of a plurality of pixels of the image data.

12. The image processing apparatus as claimed in claim 11, wherein the horizontal reduction unit is configured to compute the average by use of an adder and a bit-shift circuit.

13. An image processing method, comprising the steps of:

receiving line data scanned in a main scan direction of an image at predetermined data speed;

applying to the line data an enlargement process for enlarging the image by an enlargement factor equal to an integer so as to produce enlarged data; and

applying to the enlarged data a reduction process for reducing the enlarged image by a desired reduction factor so as to produce reduced data,

wherein the above steps are performed as a series of processes that match said data speed.

14. The image processing method as claimed in claim 13, further comprising a step of cutting out a portion of an original image as a partial image, wherein the line data is line data of the partial image.