JP3828010B2 - Image receiving system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image distribution / reception technique in which image data transmitted using a communication infrastructure such as a LAN (Local Area Network) line or the Internet is converted into a video signal and displayed on a video monitor.
[0002]
[Prior art]
A conventional image data transmission form and a display form on a video monitor will be described with reference to FIG. FIG. 4 is a block diagram showing a configuration of a conventional surveillance camera system. The upper block configuration in FIG. 4 shows the overall configuration of the surveillance camera system, and the lower block configuration shows the internal configuration of each of the receiving apparatuses 10-1 to 10-4. Each of the receiving apparatuses 10-1 to 10-4 includes a video encoder (A / D) 41, a scaler 42, and a buffer memory 43.
In FIG. 4, the imaging device 200-1 captures the monitoring visual field range, converts the acquired image into a video signal, and outputs the video signal to the reception device 10-1. Similarly, the imaging devices 200-2, 200-3, and 200-4 capture the respective monitoring visual field ranges, convert the acquired images into video signals, and receive the receiving devices 10-2, 10-3, and , Output to 10-4.
[0003]
Each of the receiving devices 10-1, 10-2, 10-3, and 10-4 converts the input video signal into image data in a format that can be displayed on the multi-screen of the surveillance camera system, and converts the converted image data. Each is output to the 4-screen multiplexing unit 60. The 4-screen multiplexing unit 60 generates one-screen data from the input image data, stores it in the frame memory, and outputs it to the video monitor 50 through the video encoder (D / A) 46. The video monitor 50 displays the input image data on the display screen.
[0004]
The four-screen switcher 600 switches the image displayed on the video monitor 50 in accordance with a user instruction. For example, if the user's instruction is to display all four images acquired by the imaging devices 200-1, 200-2, 200-3, and 200-4 on the video monitor 50, the display on the video monitor 50 is displayed. Images input from the receivers 10-1, 10-2, 10-3, and 10-4 are displayed in the screen display areas 5-1, 5-2, 5-3, and 5-4, respectively. The image data is output to the video monitor 50 as shown. Also, for example, if the user's instruction is to display only the image acquired by the imaging device 200-1 on the video monitor 50, the entire display screen area of the video monitor 50 is input from the receiving device 10-1. The image data is output to the video monitor 50 so that the image is displayed. For example, if the user's instruction is to display the images acquired by the imaging device 200-1 and the imaging device 200-3 on the video monitor 50, for example, the display area 5 on the display screen of the video monitor 50. The image input from the receiver 10-1 is displayed in the display area that combines -1 and 5-3, and the image that is input from the receiver 10-3 in the display area that combines display areas 5-2 and 5-4 The image data is output to the video monitor 50 so that the displayed image is displayed.
[0005]
In the above description, the surveillance camera system has been described. However, it is not necessary to limit to a surveillance camera system as long as it is an image distribution / reception system that outputs video signals and image data to a receiving device by an image data output device and receives them to display on a multi-screen.
Furthermore, in the above description, the image pickup apparatus is taken as an example as an image data output device that transmits image data to the reception apparatus. However, a device that transmits image data to a receiving device, that is, an image distribution device is not limited to an imaging device, and need not be limited as long as it is a device that outputs image data. In that case, there are various possible formats for the output image data, including NTSC and PAL video signals, and compressed image data such as MPEG and JPEG. It suffices if the image format can be converted into an image format required for the system.
[0006]
Next, an image distribution / reception system that receives a plurality of conventional image data from a LAN (Local Area Network) line or a network line such as the Internet and displays the image data on a video monitor will be described with reference to FIG. FIG. 3 is a block diagram showing a configuration of a conventional image distribution / reception system using four WEB (World Wide Web) image data reception video signal output devices, one four-screen switch, and one video monitor. .
Web receivers 100-1, 100-2, 100-3, and 100-4 are coupled to LAN line 3, respectively. LAN line 3 is also connected to the image distribution device. That is, the distribution server 21-1 as an image distribution device, 21-k (k is a natural number) and the web distribution devices 20-1, 20-2, ..., 20-n are LAN lines. It is connected to 3 (n is a natural number). Furthermore, the distribution servers 22-1,..., 22-m are connected to the LAN line 3 via the Internet 4 (m is a natural number).
[0007]
In the example of FIG. 3, the distribution servers 22-1,..., 22-m are coupled to the web receivers 100-1, 100-2, 100-3, 100-4 via the Internet 4 and the LAN line 3. Has been. However, without the LAN line 3, the distribution servers 22-1, 22-m are directly connected to the web receivers 100-1, 100-2, 100-3, 100-4 via the Internet 4 only. It may be combined.
Further, only either the distribution server or the WEB distribution device may be connected, another image distribution device, or a combination thereof. For example, the image data output device shown in FIG. 3 is an imaging device, for example, a WEB distribution device or a distribution server. The web distribution apparatus or distribution server may be input with the video signal output from the imaging apparatus, or may be acquired from an image reproduction apparatus such as a VTR or an image data storage apparatus such as a hard disk.
[0008]
The web receivers 100-1, 100-2, 100-3, 100-4 are respectively connected to the LAN line 3 or the Internet 4 according to user instructions. ,..., 20-n, or distribution server 21-1,..., 21-k, or distribution server 22-1,.
For example, according to the user's instruction, the WEB receiving device 100-1 and the distribution server 21-1, the WEB receiving device 100-2 and the distribution server 22-1, the WEB receiving device 100-3 and the WEB distribution device 20-1, The web receiver 100-4 and the web distributor 20-2 are connected to each other.
[0009]
In addition, according to the user's instruction, the position for displaying the image output by the web receivers 100-1, 100-2, 100-3, 100-4 is set to the display position 5-1, 5-2, Select from 5-3 and 5-4.
FIG. 3 shows a case where the display of the video monitor 5 is divided into four screens, and image data given from different image distribution devices is displayed on each of the four divided screens. -2, 100-3, and 100-4 respectively transmit image data from separate image distribution apparatuses. For example, the image data of the web receiver 100-1 is at display position 5-1, the image data of the web receiver 100-2 is at display position 5-2, and the image data of the web receiver 100-3 is at display position 5. 3 and the image data of the web receiver 100-4 are displayed at display position 5-1.
[0010]
Web receivers 100-1, 100-2, 100-3, 100-4 have received selective connection with distribution servers 21-1, 22-1 and web distribution apparatuses 20-1, 20-2 respectively. Decompress the image data and output it to the 4-screen switcher 600.
The 4-screen changer 600 sequentially inputs video signals from the web receivers 100-1, 100-2, 100-3, 100-4, and multi-screen video monitor 5 (4 screens in FIG. 3), that is, Scaling is performed to a size that can be displayed in each of display areas 5-1 to 5-4, and when video data for multiple screens has been prepared, it is output to video monitor 5 as one image.
The video monitor 5 receives the image from the 4-screen switch 600 and displays it on the display screen. At this time, the image data input from the 4-screen switching device 600 is one image displayed in all of the display areas 5-1, 5-2, 5-3, and 5-4, and the video monitor 5 The image displayed on the screen is updated each time an image is input from the 4-screen switch 600.
[0011]
[Problems to be solved by the invention]
In the above-described conventional technology, a point-to-point connection is generally used, and one corresponding receiving device is required for one device (image distribution device) that outputs image data. Furthermore, in order to display a multi-screen, a multi-screen switch such as a four-screen switch is necessary. Therefore, when there are a plurality of image distribution apparatuses and one wants to simultaneously view the image data output from any device, one reception apparatus is required for each of the image distribution apparatuses desired to be simultaneously viewed. There has been the drawback of requiring a switch with a number of switching channels corresponding to the number of these receivers.
[0012]
It is also possible to connect each image distribution device to a personal computer and use the personal computer as a receiving device and an image switch to display an image of any image data output device on the display screen of a video monitor or personal computer. However, generally the operation of personal computers is unstable and often freezes or hangs up. When a freeze or hangs up in an emergency, the image at that point cannot be seen, and the computer restarts. In addition, there are drawbacks that require labor and time.
[0013]
In addition, in the above-described conventional technology, an image transmitted from each image distribution device such as a distribution server may be used in another system or another WEB reception device, and the image distribution device side may respond to the distribution destination. The disadvantage is that the image size cannot be changed. Therefore, on the WEB receiver side, a scaling function for the received image size is required. If the data is the image size information read and encoded for each image distribution device or for each image, the decompression setting and the scaling setting are made. There is a need.
Also, an image distribution device via the Internet may have a large difference in image data transfer capability compared to an image distribution device connected directly to a LAN line. At this time, if the update rate of the video monitor is matched with the image distribution apparatus having the smallest transmission rate such as via the Internet, there is a drawback that the image update rate of the entire video monitor becomes small.
[0014]
The object of the present invention is to eliminate the above-described drawbacks, reduce the number of hardware configurations of the prior art, and acquire image data from a desired image distribution device that operates stably regardless of the number of image distribution devices. An object of the present invention is to provide an image receiving system capable of performing the above. Another object of the present invention is to eliminate the above-mentioned drawbacks and to match the video monitor update rate to the image transmission apparatus with the smallest transmission rate, regardless of the image size from the image distribution apparatus. It is another object of the present invention to provide an image receiving system in which image updating of the entire video monitor is quick.
[0015]
[Means for Solving the Problems]
In order to achieve the above goal, the image receiving system of the present invention displays a multi-screen on one video monitor without using a multi-screen switch.
In addition, the image receiving system of the present invention enables the selection connection of Pint To Multipoint from the connection of Point To Point, and displays it on a single video monitor. That is, the image receiving system of the present invention is an image receiving system that receives a plurality of encoded image data respectively distributed from a plurality of image distribution apparatuses via a LAN (Local Area Network) line or the Internet. A video monitor for displaying a plurality of received images, and a receiving device for generating video data for displaying the received plurality of image data on a multi-screen on the video monitor. The image data is displayed on the video monitor in multiple screens.
[0016]
In the image receiving system of the present invention, the receiving device converts each of a plurality of pieces of image data distributed from the plurality of image distributing devices received via the LAN line or the Internet into a predetermined image format. An image input interface, a storage device for storing the converted image data, a buffer memory for reading and storing the stored image data, and inputting the image data in the buffer memory and decoding it into video data Codec And a scaler for converting the decoded video data to a predetermined image size, and a frame memory for reading at least one video data converted to the predetermined image size and storing video data for one frame. It is a thing.
[0017]
In the image receiving system of the present invention, the buffer memory is a first buffer memory and a second buffer memory, and one of the first buffer memory and the second buffer memory is connected to the storage device from the storage device. When the stored image data is read out and stored, the image data stored in the other is read out.
In the image receiving system of the present invention, the frame memory includes a first frame memory and a second frame memory, and one of the first frame memory and the second frame memory receives video data from the scaler. When the video data is read out and stored, the video data stored in the other is read out.
[0018]
Further, the storage device of the image receiving system of the present invention has a data area for writing image data twice as many as the number of images to be displayed on the video monitor, and an image previously written in one of the data areas The data is held, and the written image data is read out when it is time to read the currently written image data into the buffer memory before the writing is completed.
The receiving device of the image receiving system according to the present invention is characterized in that the received plurality of image data are processed in units of one frame.
[0019]
The image receiving system of the present invention includes the image input interface, the storage device, the buffer memory, Codec Control means for controlling the scaler and the frame memory, the control means analyzing information of the image data input from the image input interface, Codec Alternatively, control information of the image data or video data is supplied to the scaler. Further, the receiving device of the image receiving system of the present invention includes an input / output interface for inputting a user instruction and outputting output information corresponding to the instruction, and the control device of the receiving device includes a user's instruction. An arbitrary image distribution device is selectively connected to the video monitor according to an instruction, and the received plurality of image data are displayed on the video monitor.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described with reference to FIG.
FIG. 1 is a block diagram showing the configuration of an embodiment of the image distribution / reception system of the present invention. FIG. 1 shows the configuration of the conventional image distribution / reception system shown in FIG. 3, instead of four web receivers 100-1 to 100-4 and one four-screen switch 600. It is equipped with device 1-1. The LAN line 3 is coupled with at least one other receiving device (represented by the WEB receiving device 1-2). Web receiver 1-1 is coupled to video monitor 50.
[0021]
In FIG. 1, a WEB image data reception video signal output device (WEB reception device) 1-1 is an image distribution device 2-1 2-2,..., 2- connected to a LAN line 3 or the Internet 4. The connection is selected from m (m is a natural number), or Web distribution devices 20-1, 20-2 to 20-n, distribution servers 21-1 to 21-k, and 222-1 to 22-m. Select a display area from display areas 5-1 to 5-4 on video monitor 5. Since FIG. 1 is a case where four screens are displayed, each of the four image distribution apparatuses (distribution server or WEB distribution apparatus) selected one by one in display areas 5-1 to 5-4 is displayed. .
[0022]
WEB reception device 1-1 performs selective connection from the image distribution device, decompresses the received image data, and scales it to the video data size that can be displayed in the display areas 5-1 to 5-4 on the multi-screen display of video monitor 5 I do.
Video data that has been subjected to decompression processing and scaling processing of image data for multiple screens (4 screens in FIG. 1) is stored in a frame memory (described later). To update the display on video monitor 5.
[0023]
The image size of the image sent from each image distribution device may be used by other image reception devices such as the WEB reception device 1-2, and the image distribution device side may not be able to change the image size. . Therefore, the WEB image receiving device 1-1 needs to have a flexible scaling function of the image size. For the image transmitted from the image distribution device side, the image size information is read for each received image and is encoded. If the data has been converted, it is necessary to decompress and then set the scaling.
[0024]
Since the distribution servers 22-1 to 22-m are connected to the WEB receiver 1-1 from the Internet 4 through the LAN line 3, the image distribution apparatus (WEB distribution) connected directly to the LAN line 3 is connected. Compared with the apparatuses 20-1, 20-2 to 20-n and the distribution servers 21-1 to 21-k), there is often a great difference in the transmission capacity of image data.
At this time, the image distribution apparatus (for example, distribution server) having the smallest transmission capability (transmission rate) is used to update the display of the video monitor because the frame memory is updated when the video data for four screens is prepared. In accordance with 22-1), the display image update rate of the video monitor 5 becomes very slow.
As described above, when the connection is low in distribution capability and transmission capability (or transfer capability), for example, processing such as maintaining the entire image display update rate by reusing the previously used image data is performed. Do.
[0025]
An example of the hardware configuration of the WEB receiver 1-1 in FIG. 1 will be described with reference to FIG. FIG. 1 is a block diagram showing the configuration of an embodiment of the WEB receiver of the present invention.
A CPU (Central Processing Unit) 11 controls each component of the WEB receiver 1-1 according to a program stored in advance. In FIG. 2, signal lines such as a data bus that connect the CPU 11 and each component of the web receiver 1-1 are omitted.
The input / output interface (I / F) 7 is given control information from an input device or an input terminal (not shown), and supplies the given control information to the CPU 11. In addition, since this receiving device has a server function, it can also be controlled using a browser function such as a homepage from a LAN line. The CPU 11 controls the WEB receiver 1-1 according to a program stored in advance based on the input control information, and processes the input image data. The signal path for accessing from the CPU 11 is not particularly shown.
The input / output I / F 7 receives output information from the distribution device and the CPU 11 and outputs it to output devices (not shown) (for example, a monitor, a speaker, an output terminal, etc.).
[0026]
The LAN interface (I / F) 10 receives encoded image data from the LAN line 3 or the Internet 4, converts it into an image format that can be processed by the web receiver, and outputs it to the CPU 11. The CPU 11 writes the input image data into the storage device 12 once, reads it as necessary, and outputs it to the buffer (BUF) memory 13-1 or 13-2. The storage device 12 is, for example, an SDRAM (Synchronous Dynamic Random Access Memory).
[0027]
The LAN I / F 10 inputs encoded image data from the LAN line 3 or the Internet 4 in units of one frame, and the storage device 12 also stores the image data in units of one frame. That is, the LAN I / F 10 inputs encoded image data from the LAN line 3 or the Internet 4 in units of one frame, and the storage device 12 also stores the image data in units of one frame. The storage device 12 includes two storage areas for each of the display areas 5-1, 5-2, 5-3, and 5-4 of the video monitor 5, and stores image data for one frame each.
[0028]
The storage device 12 has, for example, a data structure as shown in FIG. FIG. 5 is a diagram for explaining an embodiment of the data structure of the storage device used in the present invention. For example, the image data for display in the display area 5-1 is already stored in the data area 51-1, and the image data is currently input to the data area 51-2 via the LAN I / F 10. Suppose you are on the way. At this time, image data for display in the display area 5-2 is stored in the data areas 52-1 and 52-2 frame by frame, and the stored time is “valid” in the new data area. The flag is raised. Similarly, image data for display in the display area 5-3 is stored in the data areas 53-1 and 53-2 frame by frame, and the stored time is “valid” in the new data area. The flag is raised. Similarly, the data areas 54-1 and 54-2 store image data for one frame at a time in the display area 5-4, and the stored time is “valid” for the new data area. The flag is set.
[0029]
Next, when new image data is stored via the LAN I / F 10, the corresponding two data areas (for example, if the image data is to be displayed in the display area 5-2, the data area 52- 1 or 52-2), new image data is overwritten in the data area (in the example of FIG. 5, data area 52-1) where the flag “valid” is not set.
If there is an instruction to read to the BUF memory 13-1 or 13-2 before the image data is stored for one frame, the CPU 11 is flagged as “valid”. The image data is read again from the data area (data area 52-2 in the example of FIG. 5) and output.
The time for the CPU 11 to input new image data via the LAN I / F 10 and store it in the storage device 12 depends on the transmission rate of the image data input from the LAN line 3 or the Internet 4.
[0030]
The timing at which the CPU 11 reads the image data from the storage device 12 and reads it into the BUF memory 13-1 or 13-2 and the subsequent operation timing are the vertical synchronization output from the video encoder 19 that outputs to the video monitor. Pulse V _SYNC It is synchronized with the timing. The video encoder 19 is, for example, an NTSC encoder. Vertical sync pulse V from video encoder 19 to other circuit units _SYNC The signal path for supplying is not shown.
For example, for the NTSC system, the vertical sync pulse V _SYNC The timing cycle is about 15 msec. Synchronous with this cycle, switching between BUF memories 13-1 and 13-2, switching between frame memories 17-1 and 17-2, etc. Processing is performed.
[0031]
The BUF memories 13-1 and 13-2 respectively write image data as they are input. Then, each of the BUF memories 13-1 and 13-2 reads out the written image data and outputs it to the selector 14. The selector 14 controls the image data to be input from either the BUF memory 13-1 or 13-2, and the input image data is Codec Output to (CODEC) 15. Codec After processing the input image data, it sends an interrupt signal to the CPU 11 to inquire about the next processing content, acquires control information such as the image size of the input image data, and based on the acquired control information The encoded image data is converted into video data while reading the input image data. At this time, if the image data is compressed data, it is decompressed and converted.
[0032]
The image data converted as video data is output to a scaler 16. After processing the input image data, the scaler 16 Codec 15 sends an interrupt signal to CPU 11 to inquire about the next processing contents, and obtains control information from CPU 11 such as scaling information for displaying the input image data on multiple screens and information on the display position on the video monitor. Then, the input video data is processed based on the acquired control information, and the video data is written in an appropriate position in the frame memory 17-1 or 17-2.
[0033]
During these operations, the LAN I / F 10 continuously receives image data, stores it in the storage device 12, and stores it in the BUF memory 13-2 (or BUF memory 13-1) that is not read by the decoder 15. Write image data. The CPU 11 that has finished writing to the BUF memory 13-2 (or BUF memory 13-1) waits for the next processing of the decoder 15, that is, the completion of reading of the BUF memory 13-1 (or BUF memory 13-2). It becomes. The decoder 15 that has read the BUF memory 13-1 (or BUF memory 13-2) shifts to reading the BUF memory 13-2 (or BUF memory 13-1) by the selector 14.
[0034]
The frame memories 17-1 and 17-2 store video data for four screens. The selector 18 switches the video data for four screens in the frame memories 17-1 and 17-2 and updates the display on the video monitor 50. Accordingly, the switching cycle of the frame memories 17-1 and 17-2 is a cycle in which video data for four screens are aligned.
However, if the frame memory 17-1 or 17-2 is always stored in the frame memory 17-1 or 17-2 and the frame memory 17-1 or 17-2 is switched, the display of the video monitor 50 is updated. Are controlled by connections with low distribution and transfer capabilities. For connections with low distribution and transfer capabilities, the previous image data is stored in the storage device 12, and the display on the video monitor 50 is updated. The previous image data is converted into video data, written to the frame memory 17-1 or 17-2, and the display on the video monitor 50 is updated to maintain the video update rate of the connection with high distribution capability and transfer capability.
【The invention's effect】
As described above, according to the present invention, image data distributed over a LAN line or the communication infrastructure of the Internet can be displayed on a single video monitor without using a multi-screen switching device, thereby reducing the system equipment configuration. it can.
Also, Point To Multipoint can be selected from Point To Point connection, and multiple screens can be displayed on one video monitor.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of an embodiment of an image distribution / reception system of the present invention.
FIG. 2 is a block diagram showing a configuration of an embodiment of a WEB receiver according to the present invention.
FIG. 3 is a block diagram showing a configuration of a conventional image distribution / reception system.
FIG. 4 is a block diagram showing a configuration of a conventional surveillance camera system.
FIG. 5 is a diagram for explaining an embodiment of the data structure of the storage device of the present invention.
[Explanation of symbols]
1-1, 1-2: WEB receiver, 3: LAN line, 4: Internet, 5-1 to 5-4: Display area, 7: Input / output I / F, 10-1 to 10-4: Receiver 11: CPU, 12: storage device, 13-1, 13-2: BUF memory, 14: selector, 15: codec, 16: scaler, 17-1, 17-2: frame memory, 18: selector, 19: Video encoder, 20-1, 20-2 to 20-n: Web distribution device, 21-1 to 21-k: Distribution server, 22-1 to 22-m: Distribution server, 50: Video monitor, 60: 4 screens Multiplexer, 100-1 to 100-4: Web receiver, 200-1 to 200-4: Imaging device, 600: Four screen switcher.

Claims (6)

An image receiving system for receiving a plurality of encoded image data respectively distributed from a plurality of image distribution apparatuses via a LAN (Local Area Network) line or the Internet,
A video monitor that displays a plurality of received image data ;
An image input interface that converts each of the plurality of received image data into a predetermined image format; a storage device that stores the converted image data; a buffer memory that reads and stores the stored image data; and A codec that inputs image data in a buffer memory and decodes it into video data, a scaler that converts the decoded video data into a predetermined image size, and reads at least one video data converted into the predetermined image size A frame memory that stores video data for one frame, and a reception device that generates video data for displaying the plurality of received image data on the video monitor in multiple screens,
The storage device of the receiving device has a data area for writing image data twice as many as the number of images to be displayed on the video monitor, holds the previously written image data in one of the data areas, An image receiving system , wherein the written image data is read when it is time to read the image data being written to the buffer memory before the writing is completed . The image receiving system according to claim 1 ,
The buffer memory is a first buffer memory and a second buffer memory, and one of the first buffer memory and the second buffer memory reads and stores the stored image data from the storage device. An image receiving system characterized in that image data stored in the other is read out. In the image receiving system according to claim 1 or 2 ,
The frame memory is a first frame memory and a second frame memory, and when one of the first frame memory and the second frame memory reads and stores video data from the scaler, the other An image receiving system for reading stored video data. In claims 1 to image reception system according to any one of claims 3,
The receiving apparatus processes the received plurality of image data in units of one frame. In claims 1 to image reception system according to any one of claims 4,
Control means for controlling the image input interface, the storage device, the buffer memory, the codec , the scaler, and the frame memory;
The control means analyzes the information of the image data input from the image input interface and supplies the control information of the image data or video data to the codec or the scaler. The image receiving system according to any one of claims 1 to 5 ,
The receiving device includes an input / output interface for inputting a user instruction and outputting output information corresponding to the instruction;
The image receiving system, wherein the control device of the receiving device displays a plurality of received image data by selectively connecting an arbitrary image distribution device to the video monitor in accordance with a user instruction.

Images