Graphics display system with color look-up table loading mechanism

• US 7,015,928 B2
• Filed: 02/03/2004
• Issued: 03/21/2006
• Est. Priority Date: 11/09/1998
• Status: Expired due to Term

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: MacInnis, Alexander G., Tang, Chengfuh Jeffrey, Kranawetter, Greg A., Patterson, James T., Xie, Xiaodong
• Primary Examiner(s): Yang, Ryan
• Application Number:
  US10/770,851
• Publication Number:
  US 20040169660A1
• Time in Patent Office: 777 Days
• Field of Search: 345/601, 345/602, 348/650
• US Class Current: 345/601
• CPC Class Codes: G06F 3/0611 in relation to response time
• CPC Class Codes: G06F 3/0653 Monitoring storage devices or systems
• CPC Class Codes: G06F 3/0659 Command handling arrangements, e.g. command buffers, queues, command scheduling
• CPC Class Codes: G06F 3/0683 Plurality of storage devices
• CPC Class Codes: G06T 1/20 Processor architectures; Processor configuration, e.g. pipelining
• CPC Class Codes: G06T 1/60 Memory management
• CPC Class Codes: G06T 9/00 Image coding bandwidth or redundancy reduction for static pictures H04N1/41; coding or decoding of static colour picture signals H04N1/64; methods or arrangements for coding, decoding, compressing or decompressing digital video signals H04N19/00
• CPC Class Codes: G06T 9/007 Transform coding, e.g. discrete cosine transform
• CPC Class Codes: G09G 2310/0224 Details of interlacing
• CPC Class Codes: G09G 2320/0247 Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes
• CPC Class Codes: G09G 2340/02 Handling of images in compressed format, e.g. JPEG, MPEG
• CPC Class Codes: G09G 2340/0407 Resolution change, inclusive of the use of different resolutions for different screen areas
• CPC Class Codes: G09G 2340/10 Mixing of images, i.e. displayed pixel being the result of an operation, e.g. adding, on the corresponding input pixels
• CPC Class Codes: G09G 2340/125 wherein one of the images is motion video
• CPC Class Codes: G09G 2360/02 Graphics controller able to handle multiple formats, e.g. input or output formats
• CPC Class Codes: G09G 2360/121 using a cache memory
• CPC Class Codes: G09G 2360/125 using unified memory architecture [UMA]
• CPC Class Codes: G09G 2360/126 The frame memory having additional data ports, not inclusive of standard details of the output serial port of a VRAM
• CPC Class Codes: G09G 2360/128 Frame memory using a Synchronous Dynamic RAM [SDRAM]
• CPC Class Codes: G09G 5/001 Arbitration of resources in a display system, e.g. control of access to frame buffer by video controller and/or main processor
• CPC Class Codes: G09G 5/02 : characterised by the way in which colour is displayed details of colour display specific for CRTs G09G1/28; specific for flat matrix panels other than liquid crystal displays G09G3/2003; specific for liquid crystal displays G09G3/3607
• CPC Class Codes: G09G 5/024 : using colour registers, e.g. to control background, foreground, surface filling G09G5/06 takes precedence
• CPC Class Codes: G09G 5/026 : Control of mixing and/or overlay of colours in general G09G5/022 and G09G5/024 take precedence
• CPC Class Codes: G09G 5/06 : using colour palettes, e.g. look-up tables
• CPC Class Codes: G09G 5/12 : Synchronisation between the display unit and other units, e.g. other display units, video-disc players
• CPC Class Codes: G09G 5/14 : Display of multiple viewports
• CPC Class Codes: G09G 5/28 : for enhancement of character form, e.g. smoothing
• CPC Class Codes: G09G 5/346 : for systems having a bit-mapped display memory
• CPC Class Codes: G09G 5/36 : characterised by the display of a graphic pattern, e.g. using an all-points-addressable [APA] memory
• CPC Class Codes: G09G 5/363 : Graphics controllers
• CPC Class Codes: H04N 11/143 : Encoding means therefor H04N11/16 takes precedence
• CPC Class Codes: H04N 11/20 : Conversion of the manner in which the individual colour picture signal components are combined, e.g. conversion of colour television standards
• CPC Class Codes: H04N 19/42 : characterised by implementation details or hardware specially adapted for video compression or decompression, e.g. dedicated software implementation H04N19/635 takes precedence
• CPC Class Codes: H04N 19/423 : characterised by memory arrangements H04N19/433 takes precedence
• CPC Class Codes: H04N 19/436 : using parallelised computational arrangements
• CPC Class Codes: H04N 19/44 : Decoders specially adapted therefor, e.g. video decoders which are asymmetric with respect to the encoder
• CPC Class Codes: H04N 19/59 : involving spatial sub-sampling or interpolation, e.g. alteration of picture size or resolution
• CPC Class Codes: H04N 19/61 : in combination with predictive coding
• CPC Class Codes: H04N 21/42204 : User interfaces specially adapted for controlling a client device through a remote control device; Remote control devices therefor constructive details of casings for the remote control device H01H9/0235; user interfaces for controlling a tuning device of a television receiver through a remote control H03J9/00; remote control of peripheral devices connected to a television receiver through the remote control device of the television receiver H04B1/205
• CPC Class Codes: H04N 21/426 : Internal components of the client ; Characteristics thereof H04N5/44 takes precedence
• CPC Class Codes: H04N 21/42653 : for processing graphics
• CPC Class Codes: H04N 21/4305 : Synchronising client clock from received content stream, e.g. locking decoder clock with encoder clock, extraction of the PCR packets arrangements for synchronising receiver with transmitter by comparing receiver clock with transmitter clock H04L7/0012; arrangements for synchronising receiver with transmitter wherein the receiver takes measures against momentary loss of synchronisation H04L7/0083
• CPC Class Codes: H04N 21/4316 : for displaying supplemental content in a region of the screen, e.g. an advertisement in a separate window
• CPC Class Codes: H04N 21/434 : Disassembling of a multiplex stream, e.g. demultiplexing audio and video streams, extraction of additional data from a video stream; Remultiplexing of multiplex streams; Extraction or processing of SI; Disassembling of packetised elementary stream demultiplexing of data packets for data networks, e.g. RTP/UDP H04L65/00
• CPC Class Codes: H04N 21/440263 : by altering the spatial resolution, e.g. for displaying on a connected PDA
• CPC Class Codes: H04N 21/4438 : Window management, e.g. event handling following interaction with the user interface
• CPC Class Codes: H04N 21/47 : End-user applications
• CPC Class Codes: H04N 5/04 : Synchronising for television systems using pulse code modulation H04N7/56
• CPC Class Codes: H04N 5/126 : whereby the synchronisation signal indirectly commands a frequency generator
• CPC Class Codes: H04N 5/14 : Picture signal circuitry for video frequency region cameras or camera modules comprising electronic image sensors, or control thereof H04N23/00
• CPC Class Codes: H04N 5/44504 : Circuit details of the additional information generator, e.g. details of the character or graphics signal generator, overlay mixing circuits
• CPC Class Codes: H04N 5/45 : Picture in picture , e.g. displaying simultaneously another television channel in a region of the screen
• CPC Class Codes: H04N 5/46 : for receiving on more than one standard at will deflecting circuits of multi-standard receivers H04N3/27
• CPC Class Codes: H04N 7/0122 : the input and the output signals having different aspect ratios
• CPC Class Codes: H04N 7/0135 : involving interpolation processes interpolation-based image scaling G06T3/4007; interpolation for video coding H04N19/587, H04N19/59
• CPC Class Codes: H04N 9/45 : Generation or recovery of colour sub-carriers
• CPC Class Codes: H04N 9/641 : Multi-purpose receivers, e.g. for auxiliary information H04N9/642 takes precedence
• CPC Class Codes: H04N 9/642 : Multi-standard receivers

Abstract

A graphics integrated circuit chip is used in a set-top box for controlling a television display. The graphics chip processes analog video input, digital video input, a graphics input and an audio input simultaneously. The chip includes a display engine that processes graphics images organized as windows. The display engine processes graphics images formatted in any one of a plurality of formats including a color look up table (CLUT) format. A color look-up (CLUT) table loading mechanism preferably facilitates the transfer of real-time CLUT table data during graphics composition. The loading mechanism may be triggered by a window descriptor that contains a color look-up table load command.

Claims

1. A method of loading a color look up table (CLUT) for processing graphics, the method comprising:

generating a data structure that can provide an indicator to load the CLUT, wherein the data structure can alternatively be used to define graphics contents of a window;

asserting a CLUT memory request signal responsive to the indicator to load the CLUT;

resetting a write pointer for the CLUT responsive to a leading edge of the CLUT memory request signal;

asserting a CLUT memory write signal to indicate a beginning of a CLUT writing operation; and

transferring conversion data from memory to the CLUT synchronously to a memory clock.

2. The method of claim 1, wherein the indicator to load the CLUT is provided when incoming CLUT-formatted data is not supported by a current content of the CLUT.

3. The method of claim 1, wherein transferring conversion data comprises

loading first conversion data for a first data format into a first part of the CLUT in response to a first said indicator to load the CLUT, and

loading second conversion data for a second data format into a second part of the CLUT in response to a second said indicator to load the CLUT,

wherein the CLUT is capable of converting data having first and second data formats without re-loading the CLUT between the conversion of the data having the first and second data formats.

4. The method of claim 3, wherein a line from a first graphics image converted using the first conversion data and a line from a second graphics image converted using the second conversion data can be blended together and displayed on a display line of a display device.

5. The method of claim 3, wherein the indicator to load the CLUT is provided when incoming CLUT-formatted data is supported by neither of the first conversion data and the second conversion data.

6. The method of claim 1, further comprising

generating at least one data structure that defines the graphics contents of one said window, and

sorting the data structures into a sequence.

7. The method of claim 3, wherein less than all entries of at least one of the first conversion data and the second conversion data are loaded into the CLUT.

8. The method of claim 1, wherein the data structure that provides the indicator to load the CLUT also indicates when to load the CLUT.

9. The method of claim 1, further comprising displaying graphics images having non-CLUT formats while the CLUT is being loaded.

10. A color lookup table (CLUT) loading mechanism for an integrated circuit graphics display system, said mechanism comprising:

a window controller for processing a data structure that can provide an indicator to load the CLUT, and for generating a CLUT memory request signal and a CLUT memory write signal to control CLUT loading, wherein the data structure can alternatively be used to define graphics contents of a window;

a CLUT controller for resetting a write pointer for the CLUT responsive to the CLUT memory request signal;

a memory clock; and

a direct memory access (DMA) module for transferring conversion data from memory to the CLUT synchronously to the memory clock.

11. The CLUT loading mechanism of claim 10, wherein the indicator to load the CLUT is provided when incoming CLUT-formatted data is not supported by a current content of the CLUT.

12. The CLUT loading mechanism of claim 10, wherein first conversion data for a first data format is loaded into a first part of the CLUT in response to a first said indicator to load the CLUT, and second conversion data for a second data format is loaded into a second part of the CLUT in response to a second said indicator to load the CLUT, and wherein the CLUT is capable of converting data having first and second data formats without re-loading the CLUT between the conversion of the data having the first and second data formats.

13. The CLUT loading mechanism of claim 12, wherein a line from a first graphics image converted using the first conversion data and a line from a second graphics image converted using the second conversion data can be blended together and displayed on a display line of a display device.

14. The CLUT loading mechanism of claim 12, wherein the indicator to load the CLUT is provided when incoming CLUT-formatted data is supported by neither of the first conversion data and the second conversion data.

15. The CLUT loading mechanism of claim 10, wherein the window controller processes at least one data structure that defines the graphics contents of one said window, and sorts the data structures into a sequence.

16. The CLUT loading mechanism of claim 12, wherein less than all entries of at least one of the first conversion data and the second conversion data are loaded into the CLUT.

17. The CLUT loading mechanism of claim 10, wherein the data structure that provides the indicator to load the CLUT also indicates when to load the CLUT.

18. The CLUT loading mechanism of claim 10, wherein graphics images having non-CLUT formats are displayed while the CLUT is being loaded.

19. A graphics display system on an integrated circuit, comprising:

a window controller for processing a data structure that can provide an indicator to load a color look up table (CLUT), and for generating a CLUT memory request signal and a CLUT memory write signal to control CLUT loading, wherein the data structure can alternatively be used to define graphics contents of a window;

a CLUT controller for resetting a write pointer for the CLUT responsive to the CLUT memory request signal;

a memory clock;

a direct memory access (DMA) module for transferring conversion data from memory to the CLUT synchronously to the memory clock;

a display engine for receiving CLUT-formatted graphics data, and converting the CLUT-formatted graphics data into first graphics data having a common format using the CLUT, for receiving other graphics data and converting the other graphics data into second graphics data having the common format, and for blending the first graphics data with the second graphics data to generate blended graphics.

20. The graphics display system of claim 19, further comprising a video compositor for blending the blended graphics with video to generate blended graphics and video.