JPH0654429B2 - Video display controller - Google Patents

Description

TECHNICAL FIELD The present invention relates to a display device using a raster scan type cathode ray cathode ray tube (hereinafter, referred to as CRT), and particularly CR
The present invention relates to a moving image display control device for controlling display of a plurality of characters and figures while arbitrarily changing the display position on the T screen.

[Conventional technology]

The function of using a CRT as a display device and displaying information such as sentences and figures stored in a display memory (for example, a refresh memory using a dynamic memory) is an essential function of an information processing device as a man-machine interface. It is one.

2. Description of the Related Art Conventionally, a display device has a character display that associates characters and graphic pieces in small sections on a CRT screen that are regularly divided, and expresses sentences and graphics as a series of these, and information that should be displayed on the screen. The mainstream was the graphic display, where the image is expressed by a set of pixels that directly correspond to the display image.

Recently, however, game software has dominated most of the low-priced personal computers and video game devices called family computers, which are used for these purposes. The method is unsuitable.For example, it is possible to display the display target at an arbitrary position on the screen or move it gradually to an arbitrary position, for example, by realistically expressing how Halley's comet gradually moves along the orbit in outer space. A moving image display method is required, which is an important function that affects the performance of the device.

Such control of moving image display is performed by displaying a code indicating the type of a figure (hereinafter referred to as a moving image) that is dynamically moved and displayed, the display position on the screen and the attribute information of the moving image including color and brightness on the entire screen. Store as many as you can in memory,
This attribute information is read out for each horizontal scan during the display period and C
A moving image to be displayed is searched from the RT scanning position and the display position, and display processing is performed. The vertical display position is controlled by detecting the moving image to be displayed at the vertical scanning position from all the moving images at each scanning position and generating the corresponding display data, and the moving image display data is displayed as a brightness signal. The horizontal display position is controlled by the output timing of the display data when the video signal is directly converted to and output. Further, when changing the display position of the moving image, it is realized by changing the display position information by a central processing unit (hereinafter abbreviated as CPU) or an external input device.

In this way, unlike the conventional display control, in the display control of the moving image, the display position of the display target changes every moment, so in the process, a plurality of moving images of different types and shapes are scattered at arbitrary positions and displayed. The screen has an extremely complicated display state. For example, there occurs a situation in which moving images (moving image A, moving image B, and moving image C in the drawing) to be displayed are concentrated on the same horizontal scanning line (nth horizontal scanning line in the drawing) as shown in FIG. In such a case, the display data processing of a large number of moving images within a limited period such as one horizontal scanning period, that is, the display data of the moving images to be displayed is read from the display memory and the pixels directly corresponding to the optical video signal are processed. Since it is necessary to repeat the process of converting the data into data and editing the data, it may not be possible to secure a sufficient time to process the display information such as the background image, and normal display may not be performed. Therefore, the CPU is required to limit the maximum number of moving images that can be displayed within one horizontal scanning period, or to perform error processing when the limit range is exceeded.

[Problems to be solved by the invention]

As described above, in the moving image display control, the CPU constantly determines the position between the moving images from the display position and the display size of each moving image in order to avoid the inconvenience caused by the concentrated display of the moving image information on the same horizontal scanning line. If you understand the relationship and detect the deviation of the display position as described above, and if it exceeds the limit range, you can prohibit the display processing of the excess video, or limit it when changing the display position so that it does not shift. It was necessary to perform complicated location management, such as obtaining. For this reason, complicated display processing is increased, and a large load is imposed on software processing in the CPU, which is a factor of reducing the performance of the entire apparatus.

An object of the present invention is to realize, with simple hardware, a function to detect that moving picture information is displayed on the same horizontal scanning line more than allowable and prohibit display data processing of an excessive moving picture as described above. It is an object of the present invention to provide an inexpensive moving image display control device that can significantly reduce the load of software processing in.

[Means for solving problems]

A moving image display control device of the present invention includes an attribute memory that stores at least identification information indicating a type of moving image, display position information, and display size information, and a plurality of moving images based on the display position information and the display size information. From the moving image detection circuit that detects the moving image to be displayed on each scanning line for each horizontal scanning, the counting circuit that counts the detected moving images and generates a status signal when the number exceeds the allowable number, A moving image address generation circuit that sequentially generates address information of the display memory based on the identification information and reads the display data, an edit memory that stores the display data to be displayed on one scanning line as pixel data of the scanning line, and a counting A means for suppressing the moving picture detecting operation of the moving picture detecting circuit, the display data reading operation in the moving picture address generating circuit, and the writing operation to the editing memory by the circuit status signal

In this way, the number of detections of moving images to be displayed for each horizontal scanning is counted, and when the allowable number is exceeded, the display data processing of moving images is prohibited and the moving images to be displayed on each horizontal scanning line are limited. By displaying in this way, the load of software processing on the CPU can be significantly reduced.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a moving image display control device of the present invention. The moving image display control device of the present embodiment is a CP
U1, a display memory 2 for storing the shape data of the moving image,
An attribute memory 3 is stored for each moving image, such as its identification code, display position, and display size, which is necessary for displaying the moving image according to the number of moving images to be displayed on the full screen, and an address is specified for sequentially reading the attribute information. A moving picture search counter 4, a moving picture detection circuit 5 that detects a moving picture to be displayed in each horizontal scan from the display position information and generates a moving picture detection signal 6, and a moving picture detection signal 6 is input to count the detected moving pictures. The moving picture counting circuit 7, the moving picture address generating circuit 8 for generating the address information of the display memory 2 based on the identification code for reading the shape data of the moving picture from the display memory 2, and the shape data directly correspond to the display signal output. Edit memory 9 for converting and editing and storing the converted pixel data, and edit memory for generating address information of the edit memory 9 based on moving image display position information and scanning position information Dress control circuit 10, writing control circuit 11 of edit memory 9 for converting shape data read from display memory 2 into pixel data according to attribute information such as color and luminance information, scan timing signal of CRT 17, and scan position information. , A video signal register 13 for converting the pixel data read from the editing memory 9 in parallel and serially in synchronization with the scanning system, a serial display signal 14, a scanning timing signal, and a background image display signal. A video signal generating circuit 16 for generating a video signal for directly driving the CRT 17 by mixing 15 and an address line 18
Data input / output line 19 and address selection circuit 2
0, 21 and data bus buffers 22, 23.

The display memory 2 and the attribute memory 3 are connected to each other via the address line 18 and the data input / output line 19, the address selection circuits 20 and 21, and the data bus buffers 22 and 23 of the CPU 1, and the CPU 1 via these control lines. The display memory 2 or the attribute memory 3 is accessed. The edit memory 9 has a storage capacity of pixel data corresponding to the number of pixels required for display of at least one horizontal scanning line, and directly displays pixel data of a moving image or a background image such as display timing or video signal level in a non-display period. Is converted into pixel data corresponding to, edited and stored.

The operation control of the moving image display is performed first by the CPU prior to the display operation.
The shape data of the moving image is stored in the display memory 2 and the attribute information is stored in the attribute memory 3 by the external device 1 or the like. When the display processing cycle is activated, the moving image search counter 4 is operated to search for the moving image to be displayed in each horizontal scan from the attribute information of these moving images, and the address information of the attribute information is generated. The address selection circuit 21 selects the output of the moving picture search counter 4 as the addressing information of the attribute memory 3 and sequentially reads the moving picture attribute information from the attribute memory 3. The moving image detection circuit 5 compares the display position information and display size in the vertical direction with the vertical scanning information of the scanning signal generation circuit 12 to determine whether at least a part of the scanning line should be displayed. And detect. Such moving image search is performed for all moving image information stored in the attribute memory 3, and is repeated for each horizontal scan. When a moving image to be displayed is detected, the moving image detection circuit 5 activates the moving image detection signal 6 and the moving image search counter 4 is activated.
Is suspended and the addressing information in the attribute memory 3 is held. Therefore, the moving image search is temporarily suspended in order to process the display data of the detected moving image. Further, the moving image counting circuit 7 updates the value with the moving image detection signal 6. Next, display data processing of the detected moving image is performed. The moving image address generation circuit 8 takes in the detected moving image identification code, generates address information of the display memory 2, and accesses the display memory 2 via the address selection circuit 20. The display data read from the display memory 2 is written in the write control circuit 1
1 is converted into pixel data corresponding to direct display such as display timing or video signal level and edited, and edited by the editing memory address control circuit 10 based on horizontal display position information of moving image. Stored in. When the display data processing of the detected moving image is completed, the moving image search is started again. By repeating the above operation, a moving image to be displayed on one horizontal scanning line is sequentially searched, pixel data is generated and stored in the editing memory 9. The pixel data of the moving image edited and stored in the editing memory 9 in this way is sequentially read out by selecting horizontal scanning information as addressing information in the editing memory address control circuit 10 during the display period, and then in parallel in the video data register 13.
The signals are serially converted into the serial display signal 14. Serial signal 14
Is mixed with the display signal 15 of the background image in the video signal generation circuit 16 to be a video signal and supplied to the CRT 17.
When the moving picture search circuit 7 starts the moving picture search operation for each horizontal scanning, the moving picture counting circuit 7 enables the moving picture detection signal 6 to be subsequently decremented and updated every time a moving picture is detected. For example, if the overflow signal 24 is a signal indicating the occurrence state of a borrow in the decrement operation, even if the moving image detection signal 6 is activated when the value of the moving image counting circuit 7 is a value other than "0", the overflow signal 24 is activated. It does not affect the video display processing. However, when the moving image detection signal 6 is activated when the value of the moving image counting circuit 7 is "0", the overflow signal 24 is activated. The overflow signal 24 is input to the moving image detection circuit 5, the moving image address generation circuit 8, the write control circuit 11, and the like,
In the activated state, it acts to prohibit editing processing of moving image shape data and subsequent moving image search. Further, the overflow signal 24 is reset at the start of the next horizontal scanning to restart the moving image search.

FIG. 2 is a book diagram of the second embodiment of the present invention. The same parts as those in the above-described embodiment are designated by the same reference numerals, and the write control circuit 11, the address control circuit 10, the edit memory 9 and the video data register 13 of the edit memory 9 are put together in a broken line. And the control circuit 100. In this embodiment, the CPU 1 previously sets the number of moving images that can be displayed on one horizontal scanning line in the buffer register 101 via the data input / output line 19, and the moving image counting circuit 7 sets the value of the buffer register 101 for each horizontal scanning. Is loaded as an initial value, and decrements each time a moving image is detected. When a moving image exceeding the allowable number is detected, the overflow signal 24 is activated. The overflow signal 24 is connected to the data input / output line 19 via the data bus buffer 102,
1 can read the state of the overflow signal 24 and recognize that a moving image exceeding the allowable number is located on one horizontal scanning line. Further, the output of the moving image search counter 6 is also transmitted via the data bus buffer 103 to the data input / output line 1.
9, the addressing information in the attribute memory 3 is read when the detected moving images exceed the allowable number,
It is possible to perform necessary processing according to the display state such as determining the type of overflowed moving image and changing the display position information of the corresponding moving image. In addition, buffer register 1
Since the allowable number can be changed by rewriting the value of 01, it is possible to control the time constraint etc. required for the moving image display processing according to the application.

Further, FIG. 4 is a block diagram showing a third embodiment of the present invention. In this embodiment, the display data of the background image is stored in the display memory 2 in addition to the shape data of the moving image. Also,
Similar to the above-described embodiment, the CPU 1 sets the maximum number of moving images that can be displayed on one horizontal scanning line in the buffer register 101, and the moving image counting circuit 7 loads the value of the buffer register 101 as an initial value for each horizontal scanning. , Decrements every time a moving image is detected, and activates the overflow signal 24 when a moving image exceeding the allowable number is detected. The overflow signal 24 is input to the moving picture detection circuit 5, the moving picture address generation circuit 8, the write control circuit 11 and the OR gate 204, and in the activated state, prohibits subsequent moving picture search and moving picture display data processing. Also,
The overflow signal 24 is reset every time horizontal scanning is started. The detection end signal 20 is input to the other input of the OR gate 204 when the moving picture detection circuit 5 has finished searching for all moving pictures.
3 is generated, and the output signal 205 of the OR gate to which this signal is input is the background image address generation circuit 200, the background image position information generation circuit 202, the edit memory address generation circuit 10, the write control circuit 11, and the address selection circuit. Two
It is input to 0. When the output signal 205 of the OR gate is activated, the address selection circuit 20 performs switching control so that the output of the background image address generation circuit 200 is supplied to the display memory 2, and the display data of the background image is read from the display memory 2. In the background image address generation circuit 200, the display start address is preset every horizontal scanning, the display address is updated every time the display data is read, the display memory 2 is continuously accessed while updating the display address, and the background image is sequentially displayed. Read the display data. This display data is converted by the write control circuit 11 into pixel data directly corresponding to display such as display timing and video signal level, and the background image position information generation circuit 202 is edited by the edit memory address control circuit 10.
Select with and specify the write address, edit memory 9
Stored in. Further, since the display address is updated, the display position on the scanning line of the display data read from the display memory 2 moves, and the background image position information generation circuit 202 interlocks with the storage of the display data of the background image. Then, the display position information is generated and updated based on the display start position information set in the buffer register 201. In this way, the access to the display memory 2 and the writing to the editing memory 9 are repeated to store the display data of the background image for one scanning line in the editing memory.

Here, if the allowable number of moving images is calculated from the number of access cycles in one horizontal scanning period and the number of access cycles required for processing the display data of each of the moving image and the background image and set in the buffer register 101, it is efficient. Access cycles can be assigned, and even when display data processing for moving images occurs intensively, normal display can be performed without adversely affecting display data processing for background images. For example, when displaying on a CRT with a horizontal frequency of 15.75 KHz, 1
Assuming that the access cycle is 380 nsec, the total number of access cycles in one horizontal scanning period is 167 (obtained by the calculation of 1 / 15.75 ÷ 380), and the number of display pixels in the horizontal direction of the background image is 640 pixels. If it is possible to read and process the display data for 8 pixels with a single access, it takes 80 times to finish processing the display data of the background image.
It takes a cycle. Therefore, if the horizontal size of the moving image is 64 pixels, up to 10 moving images that can be displayed can be allowed (obtained by the calculation of (167-80) ÷ (64 ÷ 8)).
Therefore, in this case, if the allowable number is set to 10 in the buffer register 101, the display data of the background image can be displayed without omission.

As described above, in this embodiment, the allowable number is set to the buffer register 10.
If the number of moving images exceeds the allowable number, or if all the moving images have been detected, the display processing cycle of the background image is started, the display memory 2 and the editing memory 3 are shared, and Different display data such as a background image can be mixed and displayed.

〔The invention's effect〕

As described above, the present invention has the following effects by counting moving images to be displayed on the scanning line for each horizontal scanning and suppressing the moving image display processing according to the count value.

Since the number of moving images to be displayed and processed within a certain period can be controlled and the other period can be assigned to the background image display process, the display memory and the attribute memory rewriting process, etc., the total display process can be optimized.

It is possible to inform the host system of the display state such as exceeding the allowable number. Therefore, the host system does not need to detect the display state of the moving image by complicated processing from the display position and display size of the moving image, and the software processing It is possible to reduce the load on the device and significantly improve the performance of the entire device.

It is also possible to provide a function of further reducing the load on the host system, such as storing the excess scanning position information and the type of moving image based on the state signal that exceeds the allowable number and causing the host system to recognize it.

It is necessary to store the display data of the moving image and the background image in the same editing memory, and to separately configure the peripheral control circuits such as the display memory and the video data register, which are indispensable for display, in the moving image display system and the background image display system. In addition, the display data of the moving image and the background image can be mixed and displayed with the minimum hardware.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of a moving image display control device of the present invention, FIG. 2 is a block diagram of a second embodiment of the present invention,
FIG. 3 is a display state diagram of a moving image, and FIG. 4 is a block diagram of a third embodiment of the present invention. 1 ... CPU, 2 ... display memory, 3 ... attribute memory,
4 ... Video search counter, 5 ... Video detection circuit, 6 ...
Video detection signal, 7 ... Video counting circuit, 8 ... Video address generation circuit, 9 ... Editing memory, 10 ... Editing memory address generation circuit, 11 ... Writing control circuit, 12 ... Scan signal generation circuit, 13 ...... Video data register, 14 ...
... Serial display signal, 15 ... Background image display signal, 16 ...
... video signal generating circuit, 17 ... CRT, 18 ... address line, 19 ... data input / output line, 20, 21 ...
... Address selection circuit, 22, 23, 102, 103, ...
… Data bus buffer, 24… Overflow signal,
100 ... Editing memory and control circuit, 101, 201
... buffer register, 200 ... background image address generation circuit, 202 ... background image position information generation circuit, 203 ... detection end signal, 204 ... OR gate, 205 ... OR gate output signal.

Claims (1)

[Claims] 1. A moving picture display control device for reading out display data of a moving picture stored in a display memory to generate a video signal to a display device, at least identification information indicating a kind of moving picture, display position information and display size information. And a moving image detection circuit that detects a moving image to be displayed on each scanning line for each horizontal scanning from a plurality of moving images based on the display position information and display size information, and the detected moving image Counting circuit that generates a status signal when the number exceeds the allowable number, and the address information of the display memory is sequentially generated based on the detected moving image identification information, and the moving image address generation that reads the display data is generated. A circuit, an edit memory that stores display data to be displayed on one scan line as pixel data of the scan line, and a motion signal in the moving image detection circuit according to a status signal of the counting circuit. Detecting operation, moving image display control device characterized by having a means for controlling the write operation to the read operation and the editing memory of the display data in the video address generating circuit.