KR20170107160A - Method and apparatus for processing graphics - Google Patents

Abstract

The present invention relates to a method and an apparatus for processing graphics. The method for processing graphics comprises the steps of: rendering image information on first to n^th layer screens for each layer screen to store a rendering result in each of first to n^th frame buffers assigned for each layer screen; composing data stored in the first to n^th frame buffers to output composition result data as well as storing the composition result data in a backup buffer; and outputting the data stored in the backup buffer when an image is not changed in a next screen of the first to n^th layer screens. According to the present invention, by using the composition result data when the image is not changed while storing the composition result data in the backup buffer, an access on an external memory is minimized, thereby reducing power consumption and heating.

Description

[0001] The present invention relates to a method and apparatus for processing graphics,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a graphics processing method and apparatus, and more particularly, to a graphics processing method and apparatus that can store a result of a composition in a backup buffer and use it when necessary.

With the advent of mobile and consumer devices with sophisticated GUI and gaming features, there is a growing need for low power consumption and low cost as well as functionality and performance requirements. Traditionally, 3D graphics accelerators have demanded very high memory bandwidth, and they also use tile-based rendering methods to minimize memory bandwidth.

The tile-based method divides the screen into several tiles and renders the tiles one at a time into an on-chip tile buffer. Rendered tiles are recorded in an external memory and read and displayed by an LCD or VGA controller. Such tile-based rendering may reduce the internal memory storage space and memory bandwidth of the graphics processing unit.

However, when a plurality of layer screens are overlaid and displayed as one screen, rendering is performed for each layer screen, and each layer screen is stored in a frame buffer set in an external memory. Then, data stored in a plurality of frame buffers is re- It is necessary to read and compose. Therefore, even if using tile-based rendering, the access to external memory increases.

Memory access outside the chip uses more power than chip internal memory access. Thus, for mobile devices requiring long battery life, it is necessary to minimize access to external memory.

Therefore, it is necessary to minimize the memory access from the outside of the chip and to process it more efficiently in terms of memory bandwidth in the case of graphics processing for a screen composed of a plurality of layers.

It is therefore an object of the present invention to provide a graphics processing method and apparatus capable of minimizing memory access by storing composition result data in a backup buffer and using it when there is no image change.

According to another aspect of the present invention, there is provided a graphic processing method including the steps of: (a) rendering image information on a first to an n-th layer screen according to a layer screen, (B) composing the data stored in the first through n'th frame buffers, outputting the composition result data and storing the data in the backup buffer, and (c) and outputting the data stored in the backup buffer if there is no image change in the next screen of the n-layer screen. If there is an image change in the next screen of the first to the n-th layer screens, steps (a) to (c) may be performed.

According to another aspect of the present invention, there is provided a graphics processing apparatus comprising first through n-th frame buffers each storing results rendered by layer screens, a backup buffer, data stored in the first through n-th frame buffers, And outputting the data stored in the backup buffer when there is no image change in the next screen of the first to the n-th layer screens, 1 to the nth layer screen, the data of the layer combining unit is output when there is an image change in the next screen.

According to another aspect of the present invention, there is provided a computer-readable recording medium having recorded thereon a program for causing a processor to execute the graphic processing method.

According to the present invention, there is provided a 3D graphics processor including the graphic processing device.

According to the present invention, access to the frame buffer set in the external memory can be minimized by using the result data stored in the backup buffer when the result data is not changed. This makes it possible to construct a system that supports high resolution using a lower performance memory. In addition, access to a low external memory can reduce the power consumption and reduce the heat generation. In particular, the present invention can be effectively applied to a case where the display refresh rate is higher than the scene change or the scene is less changed, and the performance of the 3D graphic processing apparatus can be improved by minimizing access to the external memory.

1 and 2 are block diagrams showing a configuration of a general graphic processing apparatus,
3 is a block diagram illustrating a configuration of a graphics processing apparatus according to an embodiment of the present invention, and Fig.
FIG. 4 is a flowchart provided in a description of a graphic processing method according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to the drawings.

1 and 2 are block diagrams showing a configuration of a general graphic processing apparatus. 1, each layer screen is configured from one or more application programs 50a, 50b, and 50c that constitute separate layer screens according to the operation of the display management software driven by the CPU 10 Is transmitted to the GPU (20).

The GPU 20 renders the image information received by the application programs 50a, 50b, and 50c and stores the image information in the frame buffers 60a, 60b, and 60c set for each layer screen.

When rendering of each layer screen is completed, the GPU 20 composes the data recorded in the frame buffers 60a, 60b, and 60c, and writes the data into the frame buffer 65 for display. Here, a composition is a process of merging data in order to display all layers superimposed on the screen on one screen.

The display subsystem 80 reads the data stored in the frame buffer for display 65 and causes it to be displayed on the display device 90.

2 shows a configuration using a hardware compositor.

Referring to FIG. 2, the process of rendering and transmitting image information received by the application programs 50a, 50b, and 50c to the frame buffers 60a, 60b, and 60c, Is performed by the GPU 20.

However, the composition of the data recorded in the frame buffers 60a, 60b, and 60c is performed by the hardware compositor 70 (hardware compositor). That is, the hardware composer 70 performs a data merge function for displaying all the layers overlaid on the screen in a single screen.

In order to display a plurality of layer screens in a single screen, it is necessary to write data to the frame buffer set for each layer screen, or to read data from the frame buffer set for each layer screen, The access to the server is increased.

3 is a block diagram for explaining a configuration of a graphics processing apparatus according to an embodiment of the present invention.

Referring to FIG. 3, a CPU 110, a GPU 120, and a memory 140 are connected through a bus 130 in a circuit manner. The CPU 110 and the GPU 120 may be formed of a single chip and the memory 140 is provided with frame buffers 143a, 143b and 143c and a backup buffer 145. [

In this configuration, video information for the layer screen configuration from the application program A 200a, the application program B 200b, and the application program C 200c is displayed on the display unit 110 in accordance with the operation of the display management software driven by the CPU 110 GPU < / RTI >

The image information of the application program A 200a, the application program B 200b and the application program C 200c constitute a separate layer screen, and the number of application programs constituting each layer screen is You can have more or less than one. Accordingly, if the number of application programs increases or decreases, the number of frame buffers 143a, 143b, and 143c may also increase or decrease accordingly.

The GPU 120 renders the image information on the layer screen composed of the application program A 200a, the application program B 200b and the application program C 200c on a layer screen basis.

Rendering refers to the process of creating an image from a model using a computer program, and it is possible to draw a polygon from a three-dimensional model to a two-dimensional screen. Here, a model is a description of a three-dimensional object that is woven into a data structure or a strongly-defined language, and may include geometry, viewpoints, texture mapping, lighting, shading information,

In addition, the frame-based rendering apparatus draws the entire frame buffer at once, but a more efficient method is a tile-based rendering method that divides the screen into partial regions, i.e. tiles, and sequentially rasterizes the tiles. The tile-based rendering method in this manner is generally divided into tiles having the same size and shape.

The graphics processing apparatus according to the present invention may use a tile-based rendering method or a frame-based rendering method.

When the rendering of each layer screen is completed, the GPU 120 stores rendering results in the frame buffers 143a, 143b, and 143c set for each layer screen.

The layer composition unit 150 composes the results stored in the frame buffers 143a, 143b, and 143c, and transmits the result to the display subsystem 210, and simultaneously stores the result in the backup buffer 145. [

Then, the display subsystem 220 causes the display device 230 to display the received data.

FIG. 4 is a flowchart provided in a description of a graphic processing method according to an embodiment of the present invention.

Referring to FIG. 4, the GPU 110 renders image information on the first to third layer screens, which are respectively composed of the application program A 200a, the application program B 200b, and the application program C 200c (S300). When the rendering is completed, the rendering result is stored in the first to third frame buffers 143a, 143b, and 143c allocated to the layer screens (S310).

The layer combining unit 150 composes and outputs the data stored in the first to third frame buffers 143a, 143b, and 143c and stores the data in the backup buffer 145 at step S330.

As described above, when there are more application programs and there is a layer screen of the fourth layer or more, the number of frame buffers to be composited can be increased according to the increase of the layer screen.

Next, it is determined whether there is an image change in the next screen of the first to third layer screens (S340). Whether the first to third layer screens have an image change in the next screen can be determined by comparing the hash value of the previous screen with the hash value of the previous screen and the hash value of the current screen by the CPU 110 or the GPU 120 It can be judged.

As a result of the determination in step S340, if there is no image change in the next screen of the first to third layer screens, the data stored in the backup buffer 145 is output instead of the output of the layer synthesis unit 150 (S350).

However, if there is an image change in the next screen of the first to third layer screens, steps S300 to S330 are repeatedly performed (S340).

If there is no image change in the next screen, the process of outputting the data stored in the backup buffer 145 and storing the rendering result of the GPU 120 in the frame buffers 143a, 143b, and 143c , The layer combining unit 150 does not perform the process of reading and composing data stored in the frame buffers 143a, 143b, and 143c, thereby reducing access to the external memory.

This process minimizes external memory access and lowers memory bandwidth. Memory bandwidth is a very important factor affecting the performance of 3D computer graphics systems. ,

Particularly, when the screen refresh rate of the display is higher than the frequency at which the application program changes the scene, or when the content changed by the application program is a small portion in the entire scene, the graphics processing method according to the present invention is very effective.

The data output from the layer combining unit 150 and the backup buffer 145 may be transmitted to a data compression device, an image quality improvement device, another processor, or the like in addition to the configuration that is transmitted to the display subsystem 210.

Meanwhile, the contents of the present invention are not limited to hardware or software use, but can be applied to any other computing or processing environment. But may be embodied in hardware, software, or a combination of hardware and software described in the present invention. The present invention may be implemented using circuitry. That is, it can be implemented as one or more programmable logic circuits, that is, an application specific integrated circuit (ASIC) or a logic circuit (AND, OR NAND gates) or a processing device (for example, a microprocessor, a controller).

The present invention can be implemented as a computer program on a programmable computer. Such a computer may include a processor, a storage device, an input device, and an output device. In order to implement the contents described in the present invention, the program code may be input to a mouse or a keyboard input device. These programs can be implemented in high-level languages or object-oriented languages. It can also be implemented as a computer system implemented in assembly or machine code.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It should be understood that various modifications may be made by those skilled in the art without departing from the spirit and scope of the present invention.

110: CPU 120: GPU
143a to 143c: Frame buffer 145: Backup buffer
150:

Claims (11)

(a) rendering the image information for the first to n-th layer screens according to the layer screens, and storing the rendered results in the first to n-th frame buffers allocated to the layer screens, respectively;
(b) composing the data stored in the first through n'th frame buffers, outputting the composition result data, and storing the result data in a backup buffer; And
(c) outputting data stored in the backup buffer if there is no image change in the next screen of the first through n-th layer screens. The method according to claim 1,
Wherein the steps (a) to (c) are executed when there is an image change in a next screen of the first to n-th layer screens. The method according to claim 1,
And displaying the resultant data on the display device and the data output from the backup buffer The method according to claim 1,
Wherein the composition result data and the data output from the backup buffer are output to any one of a data compression device, an image quality improvement device, and a processor. The method according to claim 1,
Wherein whether or not the image is changed in the next screen is determined by comparing the hash value of the previous screen with the hash value of the current screen. A processor-readable recording medium having recorded thereon a program for causing a processor to execute the graphic processing method according to any one of claims 1 to 5. A first through an n-th frame buffers each storing a rendered result for each layer screen;
Backup buffer;
A layer combining unit for composing the data stored in the first through n'th frame buffers and storing the resultant data in the backup buffer and simultaneously outputting the resultant data; And
And outputs data stored in the backup buffer if there is no image change in the next screen of the first to nth layer screens, and if there is an image change in the next screen of the first to nth layer screens, And a control unit for controlling the graphic processing unit to control the graphic processing unit. 8. The method of claim 7,
And a graphics processor for rendering the image information for the first to nth layer screens according to the layer screens and for storing the rendered results in the first to nth frame buffers, respectively. 8. The method of claim 7,
Wherein the control unit outputs the composition result data and the data output from the backup buffer to one of a display subsystem, a data compression apparatus, an image quality improvement apparatus, and another processor. 8. The method of claim 7,
Wherein the control unit is a processor disposed on the same chip as the graphics processing unit. 11. A 3D graphics processor comprising the graphics processing device of any one of claims 7 to 10.

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