Arbitrary zoom “on -the -fly”

• US 6,400,852 B1
• Filed: 12/23/1998
• Issued: 06/04/2002
• Est. Priority Date: 12/23/1998
• Status: Expired due to Fees

• Current Assignee: Delaware Capital Formation Incorporated (Dover Corporation)
• Original Assignee: LuxSonor Semiconductors, Inc. (Cirrus Logic Incorporated)
• Inventors: Rygh, Mark P., Miller, Edward J. II
• Primary Examiner(s): Mehta, Bhavesh
• Assistant Examiner(s): Kassa, Yosef
• Application Number:
  US09/219,815
• Time in Patent Office: 1,259 Days
• Field of Search: 382/298, 382/299, 382/305, 382/293, 382/295, 348/581, 348/596, 348/561, 345/606, 345/661
• 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: G09G 2340/0414 Vertical resolution change
• CPC Class Codes: G09G 2340/0421 Horizontal resolution change
• CPC Class Codes: G09G 5/395 Arrangements specially adapted for transferring the contents of the bit-mapped memory to the screen G09G5/399 takes precedence
• CPC Class Codes: H04N 5/2628 Alteration of picture size, shape, position or orientation, e.g. zooming, rotation, rolling, perspective, translation
• CPC Class Codes: H04N 7/0122 the input and the output signals having different aspect ratios

Abstract

A system and method of performing “on-the-fly” zooming (i.e., while the video display is in-motion) having infinite value scaling is provided to give the user the ability to zoom-up by any amount while viewing. The variable “on-the-fly” zooming function is performed by a user employing a user interface device, such as a mouse, to select a window of random size in a display screen which is playing an in-motion video display. The information obtained by the user interface device is converted into scaling information and base address information and are stored into temporary registers. On the next video synchronization signal, the scaling and base address information are loaded into registers used to perform scaling on the pixel data retrieved from the frame buffer area in the video system. The new base address ensures that the pixel data is retrieved so that only the data within the window is scaled. The retrieved video data is then scaled using the new scaling information.

Claims

1. A display system for displaying video data in a video system including a display screen, a user interface for allowing a user to interact with said display screen, and a first memory storage area for storing said video data, said display screen having an associated video blanking period, said display system comprising:

second memory storage area for storing current scaling factor information obtained from said user interface while said display screen is in-motion;

third memory storage area for storing current base address information corresponding to a retrieval starting point within a frame of video data stored in said first memory storage area obtained from said user interface while said display screen is in-motion;

means for updating during said video blanking period said second memory storage area with said current scaling factor information and said third memory storage area with said current base address information;

means for retrieving a frame of video data from said first memory storage area using said current base address information after said video blanking period;

means for scaling said retrieved frame of video data using said current scaling factor information;

means for outputting scaled video data from said scaling means to said display screen wherein video data scaling and scanning occurs while said display screen is in-motion.

2. The system as described in claim 1 wherein said current scaling factor information and said current base address information are determined when said user interface selects a window of data in said display screen.

3. The system as described in claim 2 wherein said user interface is a mouse.

4. The system as described in claim 2 wherein said user interface is a keyboard.

5. The system as described in claim 1 wherein said current scaling factor information and said current base address information are directly provided through said user interface.

6. The system as described in claim 5 wherein said user interface is a keyboard.

7. The system as described in claim 1 wherein said current scaling factor information includes vertical and horizontal scale factors.

8. The system as described in claim 1 wherein said current base address information includes a vertical address and a horizontal address of a pixel of data in a given frame of data stored in said memory area.

9. The system as described in claim 1 wherein said scaling means comprises interpolation hardware which performs computational operations using said current scaling factor information in a fixed point integer format.

10. A video system comprising:

a display screen having an associated video blanking period;

a user interface for allowing a user to interact with said display screen and video system;

a first memory storage area for storing frames of video data;

a second memory storage area for storing current scaling factor information obtained from said user interface while said display screen is in-motion;

a third memory storage area for storing current base address information corresponding to a retrieval starting point within a frame of video data stored in said memory storage area obtained from said user interface while said display screen is in-motion;

means for updating during said video blanking period said second memory storage area with said current scaling factor information and said third memory storage area with said current base address information;

means for retrieving a frame of video data from said first memory storage area using said current base address information after said video blanking period;

means for scaling said retrieved frame of video data using said current scaling factor information;

means for outputting scaled video data from said scaling means to said display screen wherein video data scaling and scanning occurs while said display screen is in-motion.

11. The system as described in claim 10 wherein said current scaling factor information and said current base address information are determined when said user interface selects a window of data in said display screen.

12. The system as described in claim 11 wherein said user interface is a mouse.

13. The system as described in claim 11 wherein said user interface is a keyboard.

14. The system as described in claim 10 wherein said current scaling factor information and said current base address information are directly provided through said user interface.

15. The system as described in claim 14 wherein said user interface is a keyboard.

16. The system as described in claim 10 wherein said current scaling factor information includes vertical and horizontal scale factors.

17. The system as described in claim 10 wherein said current base address information includes a vertical address and a horizontal address of a pixel of data in a given frame of data stored in said memory area.

18. The system as described in claim 10 wherein said scaling means comprises interpolation hardware which performs computational operations using said current scaling factor information in a fixed point integer format.

19. A method of displaying video data in a video system including a user interface and a first memory storage area for storing frames of video data, said method comprising the steps of:

obtaining current scaling factor information and current base address information while said display screen is in-motion;

updating a second memory storage area with said current scaling factor information and current base address information during a video blanking period occurring after obtaining said current scaling factor information and current base address information;

retrieving a next frame of video data occurring after said video blanking period from said first memory storage area using said current base address information; and

scaling said retrieved next frame of video data using said current scaling factor information, and outputting a scaled next frame of video data to said display screen after said video blanking period.

20. The method as described in claim 19 further comprising the step of obtaining said current scaling factor information and current base address information through said user interface.

21. The method as described in claim 19 further comprising the step of obtaining current scaling factor information and current base address information from director'"'"'s cut information.

22. The method as described in claim 19 further comprising the step of disabling director'"'"'s cut information received from a video source and using said current base address information provided through said user interface to center said frames of video data on said display screen wherein said current scaling information prior to said video blanking period and after said video blanking period is the same.

23. The method as described in claim 19 further comprising the step of using director'"'"'s cut information obtained from a video data source to obtain said current base address information so as to center said frames of video data on said display screen wherein said current scaling information prior to said video blanking period and after said video blanking period is the same.

24. The method as described in claim 19 further comprising the steps of:

providing a letterbox version of video data from a data source including director'"'"'s cut information to said video system;

extracting from said director'"'"'s cut information said current base address information and said current scaling information;

whereby a panned and scanned version of said video data is concurrently generated and displayed by said video system.