SYSTEM AND METHOD FOR DISPLAYING A ROTATED IMAGE IN A DISPLAY DEVICE

• US 20090096813A1
• Filed: 08/21/2008
• Published: 04/16/2009
• Est. Priority Date: 09/04/2007
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Patil, Vijayalaxmi, Nyamagounda, Sunil Ramappa, Muniyappa, Nataraja Kambadahalli, Murthy, Krishna Koteshwara Sridhar, Nagaraj, Guruprasad
• Granted Patent: US 8,581,933 B2
• Time in Patent Office: Days
• US Class Current: 345/649
• CPC Class Codes: G06F 16/9577 Optimising the visualization of content, e.g. distillation of HTML documents
• CPC Class Codes: G06T 1/60 Memory management

Abstract

A method controls display of an image by dividing a source image into a plurality of M×N blocks of pixels, selecting a first one of the blocks, and transferring the pixels in the first block from a source memory to a display memory, the pixels in the first block transferred based on orientation change information. The selecting and transferring steps are then repeated to transfer pixels in remaining ones of the blocks to the display memory. Each block corresponds to only a portion of the source image, where any given portion represents less than a full line of pixels in the source image.

Claims

1. A method for controlling display of an image, comprising:

(a) dividing a source image into a plurality of M×

N blocks of pixels;

(b) selecting a first one of the blocks;

(c) transferring the pixels in the first block from a source memory to a display memory, the pixels in the first block transferred based on orientation change information; and

(d) repeating steps (b) and (c) to transfer pixels in remaining ones of the blocks to the display memory, wherein 2≦

M<

total number of lines in the source image and wherein 2≦

N<

total number of pixels in any image line in the source image.

2. The method of claim 1, wherein all the divided blocks of the source image have a same size.

3. The method of claim 1, sequentially transferring each line of pixels in the first block to the display memory based on said orientation change information.

4. The method of claim 1, wherein said orientation change information provides an indication of an angle of rotation of the source image.

5. The method of claim 1, wherein the blocks are transferred sequentially to the display memory.

6. The method of claim 1, wherein the pixels in each block are transferred to the display memory before all pixels in a preceding line of the source image are transferred to the source memory.

7. The method of claim 1, wherein (c) includes:

controlling pointers of the source and display memories to transfer the pixels in each block from the source memory to the display memory.

8. The method of claim 8, further comprising:

displaying the source image with an orientation that corresponds to said orientation change information based on the blocks of pixels transferred to the display memory.

9. A system for controlling display of an image, comprising:

a display memory;

a source memory to store a source image; and

a controller to control transfer of the source image from the source memory into the display memory based on orientation change information, the controller transferring the source image by;

(a) dividing the source image into a plurality of M×

N blocks of pixels;

(b) selecting a first one of the blocks;

(c) transferring the pixels in the first block from a source memory to a display memory based said on orientation change information; and

(d) repeating steps (b) and (c) to transfer pixels in remaining ones of the blocks to the display memory, wherein 2≦

M<

total number of lines in the source image and wherein 2≦

N<

total number of pixels in any image line in the source image.

10. The system of claim 9, wherein all the divided blocks of the source image have a same size.

11. The system of claim 9, wherein the controller sequentially transfers each line of pixels in the first block to the display memory based on said orientation change information.

12. The system of claim 9, wherein said orientation change information provides an indication of an angle of rotation of the source image.

13. The system of claim 9, wherein the controller transfers the blocks sequentially to the display memory.

14. The system of claim 9, wherein the controller transfers the pixels in each block to the display memory before all pixels in a preceding line of the source image are transferred to the source memory.

15. The system of claim 9, wherein, in (c), the controller controls pointers of the source and display memories to transfer the pixels in each block from the source memory to the display memory.

16. The system of claim 15, wherein the controller controls display of the source image with an orientation that corresponds to said orientation change information based on the blocks of pixels transferred to the display memory.

17. A method for displaying an image on a display device, comprising:

receiving information designating an angle of rotation for a source image; and

performing a first operation or a second operation based upon the angle of rotation designated in said information, the first operation performed for a first range of angles and the second operation performed for a second range of angles,

wherein the first operation includes rearranging order of pixels in the source image in a buffer according to the designated angle of rotation and transferring the pixels in said rearranged order from the buffer to a display memory, and

wherein the second operation includes transferring pixels in the source image to the display memory without using the buffer, the pixels in the source image transferred to the display memory based on an order determined by the designated angle of rotation.

18. The method of claim 17, wherein the first range of angles includes 180°

.

19. The method of claim 18, wherein the second range of angles includes at least one of 90°

or 270°

.

20. The method of claim 17, wherein the first operation includes:

reversing the order of the pixels in the source image using the buffer; and

transferring the pixels in said reversed order to the display memory.

21. The method of claim 20, wherein the first operation includes:

sequentially transferring the pixels of the source image from the buffer to the display memory.

22. The method of claim 17, wherein the second operation includes:

changing an order of pixels in the source image without using the buffer; and

storing the pixels in said changed order in the display memory.

23. A system for displaying an image on a display device, comprising:

a processor;

a display memory;

a source memory to store a source image; and

a buffer coupled between the source memory and the display memory,

wherein the processor performs a first operation or second operation based on information designating an angle of rotation for the source image, the first operation performed for a first range of angles and the second operation performed for a second range of angles, and

wherein the first operation includes rearranging order of pixels in the source image in a buffer according to the designated angle of rotation and transferring the pixels in said rearranged order from the buffer to a display memory, and

wherein the second operation includes transferring pixels in the source image to the display memory without using the buffer, the pixels in the source image transferred to the display memory based on an order determined by the designated angle of rotation.

24. The system of claim 23, wherein the first range of angles includes 180°

.

25. The system of claim 24, wherein the second range of angles includes at least one of 90°

or 270°

.

26. The system of claim 23, wherein the first operation includes:

reversing the order of the pixels in the source image using the buffer; and

transferring the pixels in said reversed order to the display memory.

27. The system of claim 26, wherein the first operation includes:

sequentially transferring the pixels of the source image from the buffer to the display memory.

28. The system of claim 23, wherein the second operation includes:

changing an order of pixels in the source image without using the buffer; and

storing the pixels in said changed order in the display memory.