JP2005249920A - Image drawing method and image reproducing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image drawing method for drawing a video image on a display device effectively and an image reproducing apparatus for executing the method. <P>SOLUTION: In a personal computer main body (image reproducing apparatus) having a system bus and a microprocessor (CPU), a test video data which has the same drawing condition as the drawing condition of an inputted video data is generated and when performing each of a plurality of drawing methods to the test video data, at least either a CPU load factor or a system bus occupancy factor is measured, any one of the plurality of the drawing methods is selected according to a measured result, and a display data is generated from the inputted video data by executing the selected drawing method. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an image drawing method capable of efficiently drawing a video image on a display device and an image reproducing apparatus capable of executing this method.

  In a computer, video data for a display device is generated by giving video data to a graphics device using a graphics API (Application Programming Interface). In general, the graphics device has a video memory for storing video data, an interface for rewriting the contents of the video memory based on a command from the CPU, and an interface for reading data from the video memory and outputting it to a display device. The graphics device also includes a color conversion function for converting data in the video memory from a video format handled by the CPU to a video format handled by the display device, a scaling function for enlarging / reducing data in the video memory, and the entire display screen. It has some or all of various functions such as an overlay function for superimposing and displaying other image data at high speed. The graphics API is for utilizing various functions of the graphics device. In general, an application program can detect the capability of a graphics device and execute each function.

  An example of such a graphics API is disclosed in Non-Patent Document 1. Non-Patent Document 1 describes a DirectDraw API (Microsoft Corporation), which is a graphics API that complies with Windows (registered trademark of Microsoft Corporation), which is a computer operating system. Since DirectDraw can detect various functions supported by the graphics device, the application program can select a function to be used based on the detection result of DirectDraw and execute a drawing process. Even if the graphics device does not support a specific function, DirectDraw can emulate some of the functions as software. The drawing process can be executed.

Hoshi Masaaki, "DirectX Practical Programming", pp. 6-11, engineering company, 1998

  However, there are a wide variety of graphics devices mounted on general-purpose computers, and the functions and performance supported by the graphics devices are not uniform. For this reason, when the graphics device is configured to execute only a single drawing method, depending on the type of the graphics device, there may be a situation where sufficient drawing performance cannot be obtained or a situation where drawing cannot be performed at all. was there.

  Even when the drawing method is determined according to the presence or absence of a function supported by the graphics device, the drawing performance as hardware differs depending on the type of computer, so that the drawing method is not necessarily the optimum. It was.

  Therefore, the present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to execute an image drawing method capable of efficiently drawing a video image on a display device and this method. An object of the present invention is to provide an image reproducing apparatus capable of performing the above.

The image drawing method of the present invention can execute a plurality of drawing methods, and screen data for displaying an image on a display device by executing any of the plurality of drawing methods for input video data. A method executed by a computer having at least a system bus and control means connected to the system bus,
(A) generating test video data having the same drawing conditions as those of the input video data;
(B) measuring at least one of a load factor of the control means and an occupancy rate of the system bus when each of the drawing methods is executed on the test video data;
(C) selecting one of the drawing methods based on the measurement result;
(D) The screen data is generated from the input video data by executing the selected drawing method.

According to another image drawing method of the present invention, a plurality of drawing methods can be executed, and a display device can be provided by executing any one of the plurality of drawing methods for each of input multi-channel video data. A method executed by a computer capable of generating screen data for displaying a plurality of images and having at least a system bus and control means connected to the system bus,
(A) generating a plurality of test video data having the same drawing conditions as the drawing conditions of the input video data of the plurality of channels;
(B) For each of the combinations of the plurality of test video data and the plurality of drawing methods, measure at least one of a load factor of the control means and an occupation rate of the system bus,
(C) selecting one of the plurality of drawing methods for each of the video data of the plurality of channels based on the measurement result;
(D) The screen data is generated from the input video data of the plurality of channels by executing the selected drawing method.

  According to the present invention, test video data having the same drawing condition as the drawing condition of the input video data is generated, drawn by a plurality of drawing methods, and the load factor of the control means measured at that time and / or Alternatively, since the drawing method is selected based on the occupation rate of the system bus, it is possible to automatically select an appropriate drawing method that does not place an excessive load on the computer resources.

<First Embodiment>
FIG. 1 is a block diagram showing a configuration of an image reproducing apparatus capable of executing the image drawing method according to the first embodiment of the present invention. As shown in FIG. 1, a computer system 100 includes a computer (PC) main body 102 as an image reproducing apparatus capable of executing an image drawing method, and a PC monitor 103 as a display device connected to the PC main body 102. Have In FIG. 1, reference numeral 101 denotes a network connected to the PC main body 102.

  As shown in FIG. 1, the PC main body 102 converts a compressed video data into uncompressed video data and a network interface card (NIC) 104 that receives the compressed video data from the network 101, and draws it. A microprocessor (CPU) 105 that performs control, and a graphics device 106 that converts uncompressed video data into video data for the PC monitor 103 based on the rendering control of the CPU 105. Although not shown in FIG. 1, the PC main body 102 includes various devices equipped in a general-purpose computer, such as a storage unit such as a hard disk, a medium reading unit such as a CD-ROM drive, a keyboard, a mouse, and the like. The operation unit is provided.

  The PC monitor 103 displays an image corresponding to video data (also referred to as “screen data”) received from the PC main body 102 in, for example, a rectangular video display area 107 on the display screen. The image drawing method of the present invention is executed by the CPU 105 based on a drawing control program. The drawing control program is installed in the PC main body 102 from an information recording medium or downloaded via the network 101.

  FIG. 2 is a block diagram showing a configuration of the graphics device 106 of FIG. As shown in FIG. 2, the graphics device 106 includes a video memory 202 connected to the PC system bus 201, a color conversion / scaling engine 203, a selector 204, a digital analog converter (DA converter) 205, and the like. Have

  As shown in FIG. 2, the video memory 202 stores video data sent from the CPU or the like sent via the PC system bus 201, and outputs it to other modules as necessary. The video memory 202 has three types of memory areas, that is, a first memory 206, a second memory 207, and a screen memory 208. A screen memory 208 stores screen data of the entire screen of the PC monitor 103. The output of the screen memory 208 is input to the selector 204. The first memory 206 stores video data (hereinafter also referred to as “overlay data”) used when video data is superimposed and displayed on a part of a rectangular area of the PC screen. The output of the first memory 206 is input to the color conversion / scaling engine 203. The second memory 207 stores video data that is not displayed on the PC monitor (hereinafter also referred to as “off-screen data”), and inputs / outputs data to / from the color conversion / scaling engine 203.

  The color conversion / scaling engine 203 receives video data from the first memory 206 or the second memory 207, and converts a video data format handled by the CPU 105 into a video format handled by the PC monitor 103, and expands or reduces the video data. With scaling function to reduce. Video data obtained by the color conversion / scaling engine 203 is output to the second memory 207, the screen memory 208, or the selector 204.

  The selector 204 combines the video data stored in the screen memory 208 and the overlay data output from the color conversion / scaling engine 203 and outputs the resultant data to the DA converter 205. The DA converter 205 converts the video data output from the selector 204 into an analog video signal and outputs the analog video signal to the PC monitor 103.

  FIG. 3 is a flowchart illustrating the image drawing method according to the first embodiment. The image drawing method according to the first embodiment is executed by the CPU 105 according to a program. As shown in FIG. 3, the image drawing method according to the first embodiment refers to the drawing method selection table (step 301), and test video data (test) when no corresponding entry is detected in step 301. A process for preparing a video sequence) (step 302), a process for evaluating three types of drawing methods A, B, and C using a test video sequence (steps 303, 304, and 305), and an evaluation result It has a process of updating the drawing method selection table (step 306) and a process of executing drawing according to the drawing method selection table (step 307). In the first embodiment, for example, the following are used as the drawing methods A, B, and C.

(Drawing method A): The drawing method A is a drawing method using an overlay function. In the drawing method A, the CPU 105 prepares video data and transfers it to the first memory 206. The graphics device 106 performs color conversion and scaling on the video data in the first memory 206 as necessary, synthesizes the screen data with the screen data in the screen memory 208, and outputs this to the PC monitor 103.

(Drawing method B): The drawing method B is a method of drawing video data in the YUV format regardless of the overlay function. In the drawing method B, the CPU 105 prepares video data and transfers it to the second memory 207. The graphics device 106 color-converts the video data in the second memory 207 to the RGB format, performs scaling as necessary, transfers this to the partial area of the screen memory 208, and transfers the screen data in the screen memory 208 to the PC monitor 103. Output to.

(Drawing Method C): The drawing method C is a method for drawing video data in RGB format regardless of the overlay function. In the drawing method C, the CPU 105 prepares video data and transfers it to the second memory 207. The graphics device 106 performs scaling on the video data in the second memory 207 as necessary, transfers this to the partial area of the screen memory 208, and outputs the screen data in the screen memory 208 to the PC monitor 103.

  Next, the image drawing method of the first embodiment will be described. The PC main body 102 receives the compressed video data from the network 101. The CPU 105 converts the compressed video data into uncompressed video data, and starts image drawing processing. First, the CPU 105 refers to the drawing method selection table (step 301). The drawing method selection table stores an optimum drawing method for drawing conditions. The drawing conditions include, for example, an image size, an output magnification, a frame rate (number of drawing frames per second), and an image format (YUV or RGB). The drawing method selection table is empty in the initial state. In this case, since there is no entry for the drawing condition of the input video data in the drawing method selection table, the process proceeds to the next step 302.

  In step 302, the CPU 105 generates test video data (test video sequence) that matches the drawing conditions of the input video data. For example, if the drawing conditions of the input video data are 160 × 120 pixels, 30 fps, YUV format, test video data for several seconds having the same drawing conditions as the drawing conditions of the input video data is generated.

  In the next step 303, the drawing method A is evaluated. That is, the CPU 105 executes drawing by the drawing method A on the test video data. At this time, the CPU 105 monitors the utilization rate of the computer resource. In the first embodiment, a CPU load factor and a PC system bus occupancy rate are measured as computer resource utilization rates. However, the usage rate to be monitored may be either the CPU load rate or the PC system bus occupancy rate, or another usage rate may be monitored instead of the CPU load rate or the PC system bus occupancy rate. In addition to the CPU load factor or PC system bus occupancy rate, other utilization factors may be monitored.

  In the next step 304, the drawing method B is evaluated by the same procedure as in step 303. Further, in the next step 305, the drawing method C is evaluated by the same procedure as in step 303.

  In the next step 306, based on the CPU load factor and PC system bus occupancy rate of each of the drawing methods A, B, and C, a drawing method with the lowest CPU load factor and PC system bus occupancy rate is determined. Write to selection table. In the next step 307, using the selected drawing method, generation of screen data based on the input video data, that is, drawing processing is started. In the determination, either the CPU load factor or the PC system bus occupation rate may be used. When both the CPU load factor and the PC system bus occupancy rate are used for the determination, the determination may be made based on the total value of the CPU load factor and the PC system bus occupancy rate. Further, when both the CPU load factor and the PC system bus occupancy rate are used for the determination, the CPU load factor and the PC system weighted by the weighting coefficient are not the mere total value of the CPU load factor and the PC system bus occupancy rate. The determination may be made using the bus occupancy rate.

  FIG. 4A shows a drawing method selection table (with an overlay function and no color conversion function) in the first embodiment, and FIG. 4B shows a drawing method selection in the first embodiment. A table (when not having an overlay function and having a color conversion function) is shown. In FIGS. 4A and 4B, an item having “None” in the rendering method column indicates that rendering is difficult due to a function limitation of the graphics device.

  In step 301, if the drawing method selection table includes an entry that matches the drawing conditions of the input video data, the drawing method evaluation using the test video data (steps 302 to 306) is not performed. Then, the drawing process is started by applying the drawing method stored in the drawing method selection table (step 307).

  As described above, according to the first embodiment, test video data having the same drawing conditions as the drawing conditions of the input video data is generated, and the test video data is drawn by a plurality of drawing methods A, B, and C. The method with the lowest utilization rate of computer resources is selected, and the drawing of the input video data is executed by this method. Therefore, it is possible to automatically select an appropriate drawing method that does not place an excessive load on computer resources regardless of the type of graphics device or computer.

  In addition, the optimum combination of drawing conditions and drawing methods is stored in the drawing method selection table, and the stored drawing method is applied to input video data that matches the drawing conditions. It is not necessary to evaluate the method every time, and an appropriate drawing method that does not place an excessive load on the computer resources can be automatically selected.

<Second Embodiment>
The configuration of the image playback device of the second embodiment is the same as the configuration of the image playback device of the first embodiment, except for the image drawing procedure in the CPU 105. Therefore, in description of 2nd Embodiment, FIG.1 and FIG.2 is also referred.

  FIG. 5 is a flowchart showing an image drawing method according to the second embodiment of the present invention. The image drawing method according to the second embodiment is executed by the CPU 105 according to a program. As shown in FIG. 5, the image drawing method according to the second embodiment refers to the drawing method selection table (step 501), and test video data (test) when no corresponding entry is detected in step 501. A process for preparing (video sequence) (step 502), a process for evaluating three types of drawing methods A, B, and C using test video data (steps 503, 504, and 505), and an evaluation result It includes processing for changing the drawing conditions (step 508), processing for updating the drawing method selection table based on the evaluation result (step 506), and processing for executing drawing according to the drawing method selection table (step 507). Note that in the second embodiment, the drawing methods A, B, and C described in the first embodiment are used.

  In the first embodiment, when the drawing method is selected, drawing is performed on the test video data by three methods, and the computer resource utilization rate (for example, CPU load factor and system bus occupation rate) is the highest. A method of applying a low drawing method has been described. On the other hand, in the second embodiment, the drawing conditions are changed after the steps 503 to 505 for drawing the test video data by three methods and monitoring the computer resource utilization rate. 508 has been added.

  In step 508, it is determined whether or not the rendering method determined to have the lowest computer resource utilization rate adversely affects the stable operation of the application program. In the case of the second embodiment, when the average value of the CPU load factor exceeds 90%, it is determined that the stable operation is adversely affected. Further, in this case, the CPU load factor is reduced, the drawing conditions are changed, that is, the frame rate and output magnification are reduced, and Steps 503 to 505 are executed again. As a result, when the CPU load factor falls below 90%, the drawing method selection table is updated (step 506) and the drawing is executed (step 507), as in the first embodiment.

  As described above, in the second embodiment, similar to the first embodiment, test video data having the same drawing conditions as the drawing conditions of the input video data is generated and drawn by a plurality of methods. The method with the lowest utilization rate of computer resources is selected, and the drawing of the input video data is executed by this method. Therefore, it is possible to automatically select an appropriate drawing method that does not place an excessive load on computer resources regardless of the type of graphics device or computer.

  In addition, the optimum combination of drawing conditions and drawing methods is stored in the drawing method selection table, and the stored drawing method is applied to input video data that matches the drawing conditions. It is not necessary to evaluate the method every time, and an appropriate drawing method that does not place an excessive load on the computer resources can be automatically selected.

  Further, in the second embodiment, the possibility that the drawing by the selected method has an adverse effect on the stable operation of the system is detected, and the drawing method is optimized and the drawing method is reselected as necessary. Since it did in this way, there exists an effect that a drawing process can be reduced in weight so that a computer resource may not be overloaded.

<Third Embodiment>
The configuration of the image playback device of the third embodiment is the same as the configuration of the image playback device of the first embodiment except for the image drawing procedure in the CPU 105. Therefore, in description of 3rd Embodiment, FIG.1 and FIG.2 is also referred. Further, the image reproducing apparatus of the third embodiment is different from the image reproducing apparatus of the first embodiment in that video data of a plurality of channels is reproduced simultaneously. For this reason, the image drawing procedure in the CPU 105 of the image reproduction apparatus of the third embodiment is different from that of the first embodiment.

  FIG. 6 is a diagram showing a display example of the PC monitor according to the third embodiment of the present invention. The image reproducing apparatus according to the third embodiment is assumed to be used, for example, for simultaneously monitoring a large number of remote video images. In the third embodiment, a total of five video data of four video displays 602 to 605 under the same drawing condition and a video display 606 larger than the video displays 602 to 605 are displayed on the screen of the PC monitor 601.

  FIG. 7 is a flowchart showing an image drawing method according to the third embodiment of the present invention. The image drawing method according to the third embodiment is executed by the CPU 105 according to a program. As shown in FIG. 7, the image drawing method according to the third embodiment refers to the drawing method selection table (step 701) and test video data (test video when no corresponding entry is detected in step 701). Sequence (step 702), processing for evaluating a combination of a plurality of drawing methods using test video data (step 703), and processing for updating a drawing method selection table based on the evaluation result (step 703) 706) and processing for executing drawing according to the drawing method selection table (step 707).

  In the first embodiment, when a drawing method is selected for a single input video data, drawing is performed by three methods on the test video data, and drawing with the lowest computer resource utilization rate is performed. The method of applying the method has been described. On the other hand, in the third embodiment, a plurality of input video data is targeted, and in step 702, test video data is generated for each of the plurality of input video data.

  In step 703, drawing by a combination of three drawing methods is executed on test video data having a plurality of inputs simultaneously.

  In the case of the example of FIG. 6, since video data of two types of drawing conditions are mixed, the video data is divided into three video displays 606, video displays 602, and other video displays 603 to 605, three by three. Apply the drawing method. However, assuming a graphics device that cannot simultaneously activate a plurality of overlay functions, there are a total of 10 combinations of drawing methods (see step 703 in FIG. 7).

  Therefore, in the third embodiment, the computer resource utilization rate is measured by the combination of these ten drawing methods, the lowest combination is detected, and this is registered in the drawing method selection table in step 706. Based on this, a plurality of input video data are rendered in step 707.

  As described above, in the third embodiment, for a plurality of input video data, a plurality of channels of test video data (test video sequence) having the same drawing conditions as those of the video data are simultaneously generated. Then, it is drawn by a combination of a plurality of drawing methods, a combination of drawing methods having the lowest utilization rate of computer resources is selected, and thereby drawing of the input video data is executed. Therefore, it is possible to automatically select an appropriate drawing method that does not place an excessive load on computer resources, regardless of the type of graphics device or computer, even for video data of a plurality of channels.

  In addition, the optimum combination of drawing conditions and drawing method is stored in the drawing method selection table, and the combination of the stored drawing methods is applied to the combination of input video data that matches the drawing conditions. It is not necessary to evaluate the drawing method using video data every time, and it is possible to automatically select an appropriate drawing method that does not place an excessive load on computer resources.

<Modification>
In the first to third embodiments, three types of drawing methods A, B, and C have been described as examples of drawing methods to be evaluated, but drawing methods other than these drawing methods may be used. Also, the number of drawing methods need not be limited to three, and may be two or four or more.

  In the first to third embodiments described above, a procedure for evaluating and selecting a drawing method using test video data when an entry corresponding to the input video data does not exist in the drawing method selection table will be described. did. However, for example, by setting various drawing conditions in the drawing method selection table in advance, it is not necessary to evaluate the drawing method at the time of video data input, or the frequency of proceeding to the drawing method evaluation process is increased. You may comprise so that it may become low.

It is a block diagram which shows the structure of the image reproduction apparatus which can perform the image drawing method which concerns on the 1st thru | or 3rd embodiment of this invention. It is a block diagram which shows the structure of the graphics device of FIG. It is a flowchart which shows the image drawing method which concerns on the 1st Embodiment of this invention. (A) shows the drawing method selection table (when it has an overlay function and no color conversion function) in the first embodiment, and (b) shows the drawing method selection table (overlay function) in the first embodiment. Without color and having a color conversion function). It is a flowchart which shows the image drawing method which concerns on the 2nd Embodiment of this invention. It is a figure which shows the example of a display of the PC monitor in the 3rd Embodiment of this invention. It is a flowchart which shows the image drawing method which concerns on the 3rd Embodiment of this invention.

Explanation of symbols

100 computer system,
101 network,
102 PC main body (image playback device),
103,601 PC monitor,
104 Network interface card (NIC),
105 microprocessor (CPU),
106 graphics devices,
107 video display area,
201 PC system bus,
202 video memory,
203 color conversion / scaling engine,
204 selector,
205 DA converter,
206 first memory,
207 second memory,
208 screen memory.

Claims (8)

A plurality of drawing methods can be executed, and screen data for displaying an image on a display device can be generated by executing any one of the plurality of drawing methods on input video data, and at least a system An image drawing method executed by a computer having a bus and control means connected to the system bus,
(A) generating test video data having the same drawing conditions as those of the input video data;
(B) measuring at least one of a load factor of the control means and an occupancy rate of the system bus when each of the drawing methods is executed on the test video data;
(C) selecting one of the drawing methods based on the measurement result;
(D) The image drawing method, wherein the screen data is generated from the input video data by executing the selected drawing method. A plurality of drawing methods can be executed, and screen data for displaying a plurality of images on the display device is generated by executing any of the plurality of drawing methods for each of the input multi-channel video data. An image drawing method executed by a computer having at least a system bus and control means connected to the system bus,
(A) generating a plurality of test video data having the same drawing conditions as the drawing conditions of the input video data of the plurality of channels;
(B) For each of the combinations of the plurality of test video data and the plurality of drawing methods, measure at least one of a load factor of the control means and an occupation rate of the system bus,
(C) selecting one of the plurality of drawing methods for each of the video data of the plurality of channels based on the measurement result;
(D) The image drawing method, wherein the screen data is generated from the input video data of the plurality of channels by executing the selected drawing method. The computer further comprises storage means for storing one or more drawing methods selected in the process (c) together with drawing conditions of the one or more test video data;
(E) When drawing conditions matching the drawing conditions of the input video data are stored in the storage means, the drawing conditions are stored in the storage means instead of the processes (a) to (c). The image drawing method according to claim 1, wherein one or a plurality of drawing methods are selected, and then the processing (d) is executed. (F) Based on the measurement result in the process (b), the drawing condition of the input video data is changed, and the process (a) and subsequent steps are executed again. The image drawing method according to any one of the above. The system bus,
Control means connected to the system bus;
Connected to the system bus and capable of executing a plurality of drawing methods, and generating screen data for displaying an image on a display device by executing any of the plurality of drawing methods for input video data Drawing means for
The control means is
(A) generating test video data having the same drawing conditions as those of the input video data;
(B) measuring at least one of a load factor of the control means and an occupancy rate of the system bus when each of the drawing methods is executed on the test video data;
(C) selecting one of the drawing methods based on the measurement result;
(D) An image reproducing apparatus, wherein the screen data is generated from input video data by causing the drawing means to execute the selected drawing method. The system bus,
Control means connected to the system bus;
A plurality of drawing methods are connected to the system bus, and a plurality of images are displayed on the display device by executing any of the plurality of drawing methods for each of the input multi-channel video data. Drawing means for generating screen data for displaying
The control means is
(A) generating a plurality of test video data having the same drawing conditions as the drawing conditions of the input video data of the plurality of channels;
(B) For each of the combinations of the plurality of test video data and the plurality of drawing methods, measure at least one of a load factor of the control means and an occupation rate of the system bus,
(C) selecting one of the plurality of drawing methods for each of the video data of the plurality of channels based on the measurement result;
(D) The image reproducing apparatus, wherein the screen data is generated from the input video data of the plurality of channels by causing the drawing means to execute the selected drawing method. Storage means for storing one or more drawing methods selected in the processing (c) together with drawing conditions of the one or more test video data;
The control means is
(E) When drawing conditions matching the drawing conditions of the input video data are stored in the storage means, the drawing conditions are stored in the storage means instead of the processes (a) to (c). The image reproducing device according to claim 5, wherein one or a plurality of drawing methods are selected, and then the process (d) is executed. The control means is
(F) Based on the measurement result in the process (b), the drawing condition of the input video data is changed, and the process (a) and subsequent steps are executed again. The image reproducing device according to any one of the above.

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