WO2004114673A1

WO2004114673A1 - Transmission device, image processing system, image processing method, program, and recording medium

Info

Publication number: WO2004114673A1
Application number: PCT/JP2004/003021
Authority: WO
Inventors: Takashi Watanabe; Tsuyoshi Maeda
Original assignee: Matsushita Electric Industrial Co., Ltd.
Priority date: 2003-06-19
Filing date: 2004-03-09
Publication date: 2004-12-29

Abstract

There are provided a means and a system for rapidly and accurately transmitting a video signal via a network between screen of PC and a display device such as a projector. The transmission device includes: area decision means (15) for comparing respective blocks of a predetermined frame of a video signal consisting of frames each divided into a predetermined number of blocks to corresponding blocks of a preceding frame immediately before the predetermined frame so as to decide a rectangular area containing an area of different pixel values; extraction means (16) for extracting a video signal contained in [A] the rectangular area decided or [B] a rectangular area obtained from the decided rectangular area by applying a predetermined rule; and output means (17) for outputting the video signal extracted by the extraction means.

Description

Description transmitting device, image processing, image processing method, program, and recording medium

The present invention relates to a transmission device that performs image processing on a video signal and outputs the image signal, an image processing method, an image processing method, a program, and a recording medium. Background art

In recent years, along with the spread of PCs, the spread of wired Z wireless LANs via the Internet and intranet and the development of environments have progressed. LCD screens and large displays display PC screens for presentations. However, video signal cables that connect a PC to a liquid crystal projector, etc., are generally thick and cumbersome to handle. In addition, they often carried their notebook PCs to the hall where the presentations were made. For this reason, real-time transmission of PC screens by wireless z-wired LAN communication is required, which uses an intranet or other network and does not require carrying the PC or reconstructing the environment.

As a system for wirelessly transmitting a screen of a PC to a liquid crystal projector, there is a system disclosed in Japanese Patent Application Laid-Open No. 10-145796. The entire disclosure of the publications of Japanese Patent Application Laid-Open No. H10-10459796 is incorporated herein by reference as it is. This system encodes the video signal from the PC, transmits the signal from the transmitting device, decodes the signal received by the receiver, and projects the decoded video signal from the projector. At this time, the comparison is made between the frames and only the parts that have changed from the previous frame are PT / JP2004 / 003021

Two

Transmit.

FIG. 15 is a model diagram showing a conventional problem. 61 is a PC (Personal Computer) that has screen data. 62 is the PC screen data itself. Reference numeral 63 denotes a transmission area in which a difference value is detected as a result of comparison with the previous frame, and in which all video signals included therein are transmitted. The image data in this area is transmitted. Reference numeral 64 denotes a difference area in which a difference value is detected as a result of comparison with the previous frame.

After calculating a region in which a difference value from the previous frame is detected (hereinafter referred to as a difference region), a minimum rectangular region including all the calculated difference regions 64 is obtained as a transmission region 63. Transmit all video signals in the part included in 3. FIG. 16 shows another example of the screen data 62 shown in FIG. In FIG. 16, 62 a is the screen data itself. 64 a is a difference area in which a difference value is detected as a result of comparison with the previous frame. 63 a is a transmission area in which the difference value is detected as a result of the comparison with the previous frame, and all the video signals contained therein are transmitted.

The area in which the difference value from the previous frame is detected, that is, the difference area 64a is distributed in a point-like manner as indicated by the X mark in Fig. 16, but even in the case of such a point-like distribution. It will be referred to as a difference area 64a. The screen 62 a is processed in the same manner as the screen 62. That is, after calculating the difference area 64a, the smallest rectangular area including all the calculated difference areas 64a is determined as the transmission area 63a, and the video signal of the portion included in this transmission area 63a Is transmitted.

However, in the above configuration, in order to calculate a difference area having a pixel value different from that of the previous frame, if the coordinates of the area where the pixels have changed from the previous frame are used as the difference area, the maximum value and the minimum value of these coordinates are obtained. The area between the is the transmission area. At this time, as shown in Fig. 15 and Fig. 16, when there are two or more difference areas and they are located far apart, the area that is not the difference area, that is, the previous frame and the pixel The same image is also captured as a transmission area. For example, in FIG. 15, a considerably large area other than the transmission area 63 and the difference area 64 is included. As a result, the amount of image data to be transmitted increases, the load due to traffic increases, and the immediacy required for real-time transmission is impaired. '

That is, in the conventional system, there is a problem that the amount of image data to be transmitted increases, the load due to traffic increases, and the immediacy required for real-time transmission is impaired. Disclosure of the invention

The present invention has been made in consideration of the above problems, and does not increase the amount of image data to be transmitted, does not increase the load due to traffic, and does not impair the immediacy required for real-time transmission, an image processing system, and an image processing method. , A program, and a recording medium.

In order to solve the above-described problem, a first aspect of the present invention provides, for each block of a predetermined frame of a video signal composed of each frame divided into a predetermined number of blocks, those blocks, Area determination means for comparing each block of the frame immediately before the predetermined frame corresponding to those blocks, and determining a rectangular area including areas of different pixel values;

(1) extracting means for extracting a video signal included in the determined rectangular area (2) or a rectangular area obtained by applying a predetermined rule from the determined rectangular area;

Output means for outputting the video signal extracted by the extraction means.

In addition, the second present invention relates to each of the even numbers divided into a predetermined number of blocks. For each block of a predetermined even field or odd field of a video signal composed of a field and an odd field, the block and the block immediately before the predetermined even field or the odd field corresponding to the block are provided. Area determining means for comparing each of the blocks of the even field or the odd field and determining a rectangular area including areas of different pixel values;

Output means for outputting the video signal extracted by the extraction means.

Further, the third invention is characterized in that, when the predetermined blocks adjacent in the horizontal or vertical direction both have a rectangular area determined by the area determining means, the predetermined rule is that in the horizontal or vertical direction. The transmission device according to the first or second aspect of the present invention, which is a rule for generating a rectangular area including both rectangular areas of the adjacent predetermined block.

Further, in the fourth aspect of the present invention, the area including both the rectangular area of the predetermined pack adjacent in the horizontal or vertical direction is the predetermined block adjacent in the horizontal or vertical direction. A transmission device according to a third aspect of the present invention, which is a minimum rectangular area including both the rectangular areas.

Further, in the fifth aspect of the present invention, the predetermined rule is that the predetermined blocks adjacent in the horizontal or vertical direction both have a rectangular area determined by the area determining means, and the rectangular areas are horizontal. Or a transmission rule according to the first or second aspect of the present invention, which is a rule for generating a rectangular area that includes both the rectangular areas of the predetermined block adjacent in the horizontal or vertical direction when they are in contact in the vertical direction. It is. In a sixth aspect of the present invention, the rectangular area including both the rectangular areas of the predetermined block adjacent in the horizontal or vertical direction is the predetermined block adjacent in the horizontal or vertical direction. A transmission device according to a fifth aspect of the present invention, which is a minimum rectangular region including both the rectangular regions.

In a seventh aspect of the present invention, the extracting unit includes an encoding unit that encodes the extracted video signal,

The transmitting means according to the first or second aspect of the present invention, wherein the output means outputs the encoded video signal.

In the eighth aspect of the present invention, each of the predetermined blocks may be configured such that a receiving device that receives the transmitted video signal divides a direction orthogonal to a scanning direction when displaying the video signal. The transmission device according to the first or second aspect of the present invention, which is configured.

A ninth aspect of the present invention is the transmission device according to the first or second aspect, wherein a size of each of the predetermined blocks is changed according to a screen resolution of the video signal generator.

A tenth aspect of the present invention is the transmission device according to the first or second aspect, wherein the video signal generating device is a personal computer.

Also, an eleventh aspect of the present invention provides a video signal generating device that generates a video signal composed of frames divided into a predetermined number of blocks,

For each block of a predetermined frame of the video signal generated by the video signal generating device, the block is compared with each block of the frame immediately before the predetermined frame corresponding to the block. A region determining means for determining a rectangular region including regions having different pixel values; (1) a rectangular region obtained by applying a predetermined rule from the determined rectangular region (2) or the determined rectangular region; Extracting means for extracting the video signal included therein, and transmitting means for transmitting the video signal extracted by the extracting means. A transmitting device having

An image processing system comprising: a receiving device having an output unit that outputs a video signal transmitted from the transmitting device.

Also, a twelfth aspect of the present invention provides a video signal generator for generating a video signal composed of each even field and odd field divided into a predetermined number of blocks,

For each block of a predetermined even field or odd field of the video signal generated by the video signal generating device, the blocks and the even number immediately before the predetermined even field or the odd field corresponding to the block. Area determining means for comparing each block of the field or the odd field to determine a rectangular area including an area of a different pixel value; (1) the determined rectangular area (2) or the determined rectangular area A transmitting device comprising: extracting means for extracting a video signal included in a rectangular area obtained by applying a predetermined rule; and transmitting means for transmitting the video signal extracted by the extracting means;

Further, a thirteenth aspect of the present invention, the extracting means includes encoding means for encoding the extracted video signal,

The transmitting means transmits the encoded video signal,

The receiving device includes a decoding unit that decodes the encoded video signal transmitted from the transmission device in a format corresponding to the coding format of the coding unit.

The output means is the image processing system according to the eleventh or eleventh aspect of the present invention, which outputs the video signal decoded by the decoding means.

Further, in a fifteenth aspect of the present invention, the decoding means and the output means 13 is an image processing system according to a thirteenth aspect of the present invention to be executed.

In a fifteenth aspect of the present invention, the transmitting device also serves as the video signal generating device,

The video signal generating device and the transmitting device are personal computers,

The receiving device is the image processing system according to the eleventh or eleventh aspect of the present invention, which is a liquid crystal projector.

Also, in a sixteenth aspect of the present invention, the transmitting device also serves as the video signal generating device,

The image processing system according to the eleventh or eleventh aspect of the present invention, wherein the video signal generating device and the transmitting device are personal computers, and the receiving device is a DLP projector equipped with a network function.

In addition, the seventeenth invention provides, for each block of a predetermined frame of a video signal composed of each frame divided into a predetermined number of blocks, a block corresponding to each block and the blocks. An area determining step of comparing each block of the frame immediately before the predetermined frame with each other and determining a rectangular area including areas of different pixel values;

(1) an extraction step of extracting a video signal included in the determined rectangular area (2) or a rectangular area obtained by applying a predetermined rule from the determined rectangular area;

An output step of outputting the video signal extracted in the extracting step.

Further, the eighteenth aspect of the present invention provides a video signal comprising an even field and an odd field, each of which is divided into a predetermined number of blocks, for each block of a predetermined even field or an odd field. And the predetermined even field or odd number corresponding to the blocks An area determining step of comparing each block of the even field or the odd field immediately before the field and determining a rectangular area including areas of different pixel values;

An output step of outputting the video signal extracted in the extracting step.

Further, a nineteenth aspect of the present invention is the transmission apparatus according to the first aspect of the present invention, wherein each of the predetermined frames of the video signal composed of each frame divided into a predetermined number of blocks is provided. Area determining means for comparing the blocks and blocks corresponding to the blocks in a frame immediately before the predetermined frame to determine a rectangular area including areas having different pixel values;

(1) A program for causing a computer to function as extracting means for extracting a video signal included in the determined rectangular area (2) or a rectangular area obtained by applying a predetermined rule from the determined rectangular area. is there.

A twenty-first aspect of the present invention is the transmission apparatus according to the second aspect, wherein the predetermined even field of the video signal composed of each even field and odd field divided into a predetermined number of blocks. Or, for each block of the odd field, the block is compared with each block of the even field or the odd field immediately before the predetermined even field or the odd field corresponding to the block, and a different pixel value is obtained. Area determining means for determining a rectangular area including the area;

(1) The video signal included in the determined rectangular area (2) or a rectangular area obtained by applying a predetermined rule from the determined rectangular area is obtained. W

9

This is a program that allows a computer to function as an extraction unit.

A twenty-first aspect of the present invention is a recording medium carrying the program of the nineteenth or twenty-third aspect of the present invention, which can be processed by a computer.

According to the present invention, it is possible to regard a difference area existing at a distant position as a separate area, so that the effect of reducing transmission of an area instead of a difference area is obtained.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram showing a form of a system according to the first and second embodiments of the present invention. FIG. 2 is a flowchart illustrating a procedure of a method on the image signal transmitting side according to the first embodiment of the present invention. FIG. 3 is a block diagram showing a configuration of a PC according to the first and second embodiments of the present invention.

FIG. 4 is a model diagram of a method for detecting a difference area by dividing a screen into blocks according to the first and second embodiments of the present invention.

FIG. 5 is another model diagram of a method for detecting a difference area by dividing the screen into blocks according to the first and second embodiments of the present invention.

FIG. 6 is a flowchart illustrating a processing procedure in the projector 1 according to the second embodiment of the present invention. FIG. 7 is a model diagram of a projector that displays data transferred from a PC according to the second embodiment of the present invention via a network.

FIG. 8 is a model diagram of an example of processing in which screen data is divided into blocks in units of blocks according to Embodiment 2 of the present invention. FIG. 9 is a model diagram showing a method of calculating a transmission area by dividing a screen into blocks according to Embodiment 3 of the present invention.

FIG. 10 is an explanatory diagram showing how to name each block according to the third embodiment of the present invention.

FIG. 11 is a flowchart illustrating a method of calculating a transmission area by block area division according to Embodiment 3 of the present invention.

FIG. 12 is an explanatory diagram showing a method of calculating a transmission area by block area division according to Embodiment 3 of the present invention.

FIG. 13 is another flowchart illustrating a method of calculating a transmission area by block area division according to the third embodiment of the present invention.

FIG. 14 is another explanatory diagram showing a method for calculating a transmission area by block area division according to Embodiment 3 of the present invention.

FIG. 15 is a model diagram of the difference area detection of the conventional system.

FIG. 16 is a diagram showing another example of screen data of a conventional system.

(Explanation of code)

11 Northonore Computer

12 Projector

13 screen

Steps to acquire STE P 11 image data

STEP 12 Step of segmenting image data into blocks STEP 13 Step of detecting difference area from previous and subsequent frames

STEP 14 Step of extracting and encoding the image data in the difference area STEP 15 Step of transmitting the encoded image data via the network

STEP 16 Step to determine if it is the last block STEP 1 7 Step to release the acquired image data area

STEP 1 8 Step to determine the end of this application

21 / ヽ. -Sonanore Computer

22 screens

23 Block

24 Difference detection block

25 Inter-frame difference area

STEP 21 Steps for receiving signals over the network

STEP 22 Step of decoding the received signal in a format compatible with the encoding method

STEP 23 Display the decrypted image data

3 1 Projector

32 A memory

32 B decoder

32 C projection unit

32D LAN interface

41 No. -Sonanore Computer

42 Projector

43 screen

51 A Step for receiving image data of first block

5 1 B Decoding step of image data of first block

52 A Step for receiving image data of second block

52 B Decoding step of image data of second block

53 A Step for receiving image data of third block

53 B Decoding step of image data of third block

54 A Step for receiving image data of fourth block 54 B Decoding step of image data of 4th block

61 Northonore Computer

62 screens

63 Transmission area

64 Difference region Best mode for carrying out the invention

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

(Embodiment 1)

FIG. 1 is a diagram showing an embodiment of a system for implementing the image processing method of the present invention. Reference numeral 11 denotes a PC (personal computer) that can transmit signals through a wireless LAN interface. Reference numeral 12 denotes a liquid crystal projector having a wireless LAN interface for receiving signals, decoding received signals, and projecting the obtained image data. Reference numeral 13 denotes a screen for displaying an image projected by the liquid crystal projector. That is, the present embodiment relates to a video signal generation device such as a PC that generates a video signal, and a video display system including a display device such as a projector or a display, and particularly relates to a wireless LAN (Local Area Network). The present invention relates to a network input type video display system for transmitting a video signal generated by a PC, a camera, or the like to a display device for display.

In this system, the PC 11 acquires screen data displayed on the display of the PC 11. Here, the screen data is a video signal composed of a plurality of frames. Then, the PC 11 regards the screen data as a moving image and compares it with the immediately preceding frame to detect a region where a difference occurs (hereinafter referred to as a difference region), and detects the smallest rectangular region including the detected difference region. The transmission area Confuse. Then, the image data of the transmission area is extracted from the screen data. The extracted image data is encoded such as by compression, and the encoded data is transmitted via the LAN interface. This operation is performed by PC11. Further, the projector 12 receives a signal via the LAN interface, decodes the received signal to obtain image data, and projects the image data updated by the image data.

Also, here, the projector 12 is taken as an example, but a display device such as a CRT display plasma display, a liquid crystal display or a DLP projector can be used instead.

In this example, a LAN interface is used, but this LAN can be used either wirelessly or wired. In the case of a wireless LAN, it operates in either peer-to-peer ad hoc mode or infrastructure one mode.

Although the PC 11 is used here as an example, a terminal having a LAN interface and having screen data or a small portable terminal such as a mobile phone may be used. In addition, as a device that generates video signals, it acquires image data from a TV or VTR, detects and extracts the difference area from the immediately preceding frame, and finds the transmission area that is the smallest rectangular area including the difference area. A small attachment part with the function of acquiring image data in the transmission area, encoding it, and transmitting it to the network may be used. Moreover, also these functions may be TV or VTR having a _c, but here is an interface LAN as an example, may be Interferon over scan the system can build a network, such as B luetooth.

FIG. 3 is a block diagram showing a configuration of the PC 11.

Reference numeral 14 denotes screen data acquisition means for acquiring screen data of the PC 11. Reference numeral 15 denotes area determining means 15 for calculating a transmission area for each block. 16 is The extracting means 16 extracts the video signal included in the determined transmission area. Reference numeral 17 denotes output means for transmitting the extracted video signal. Note that these means may be realized by a program stored in the memory of the PC 11 and a CPU that executes the program.

A method of transferring the screen of the PC 11 of this system will be described. FIG. 2 is a flowchart showing a procedure of a method of transmitting an image signal according to the embodiment of the present invention. STEP 11 is a step in which the screen data obtaining means 14 collectively captures the screen data of the PC 11 and obtains the displayed screen as video data in the memory.

STEP 12 is a step of dividing the image data acquired by the region determining means 15 into blocks.

STEP 13 is a step in which the area determination means 15 obtains a difference value from the immediately preceding frame in each block, detects the difference area, and obtains a transmission area that is the smallest rectangular area including the detected difference area.

STEP 14 extracts the image data in the transmission area detected by the extracting means 16, compresses the extracted image data in a lossless encoding format or an irreversible encoding format, and encodes the image data optimal for transmission. Is a step

STEP 15 is a step in which the output means 17 transmits the encoded signal data.

STEP 16 is a step of determining whether the block that has calculated the current transmission area is the last block in the screen or the transmission area has been calculated for all blocks. If the transmission areas of all blocks have not been detected in this step, the process returns to STEP 13.

STEP 17 is a step of discarding the screen data that has been transferred. _C STEP 18 is a step of determining whether to end the process using the screen transfer system. In STEP 11, the screen data acquisition means 14 acquires the screen data of the PC I 1. Normally, screen data is copied from the memory area of the PC 11 having the screen data to the main memory by using an API (Ap- plication Programming Interface) corresponding to the OS (operating system).

At this time, in the acquisition of screen data (STEP 11), the screens are acquired at once. Therefore, it is possible to prevent a screen shift that occurs when a screen is divided and captured. In addition, insert processing to wait for screen capture processing until a signal sent to change the screen from the device driver or kernel to the display device is detected to reduce the load on PC 11 when there is no screen change You can also. It is also useful to acquire not only the API depending on the OS but also the information of the newly rewritten screen data from the graphic driver and acquire only the screen data in that area. Also, if there are multiple monitors, change the image data of one of the monitors, the image data of some of the monitors, or the information of all of them, depending on the settings from the user. it can.

In STEP 12, the area determination means 15 performs area division in units of blocks. Depending on the encoding method of the extracted image data, for example, JPEG (Joint

When performing an 8 × 8 orthogonal transformation using a matrix such as the D C (Discrete Cosine Transfo rm) of the Ph otographic Ex perts Group, a size of at least 8 pixels x 8 pixels is required. . Therefore, in this case, it is more efficient to detect a block with a block whose minimum unit is 8 pixels and is a multiple of 8 blocks.

In addition, depending on the display format of the projector that outputs the image, in the case of a decoded image in which the decoded image is displayed in the scanning line order, a block only in the horizontal direction is used. Screen switching is smoother if you divide the area. The case of performing block area division only in the horizontal direction will be described later.

However, when the block size is reduced and the area is divided into blocks, the transfer time increases because of the increase in transfer overhead, and the immediacy is impaired. When the block size is large and the division into blocks is small, image data that is not in the difference area increases as in the past, and the immediacy may be impaired.

For example, if the screen resolution of the PC 11 is 768 pixels vertically and 104 pixels horizontally, the optimal size of the block for segmentation is 102 pixels horizontally and 96 pixels vertically. If the screen resolution of PC 11 is 600 pixels vertically and 800 pixels horizontally, the optimal block size is 150 pixels vertically and 800 pixels horizontally. For other screen resolutions, if the number of vertical pixels of the screen resolution is divisible by 8 x 8, the block size height is 1/8 of the screen resolution height.

Also, if the vertical resolution of the screen resolution of PC 11 is not divisible by 8 × 8, as described in the example above, such as vertical 600 pixels × horizontal 800 pixels, it is divisible by 8 × 5 The size of the block is 1 Z5. In other cases, resizing is performed, and resizing is performed to a divisible value so as not to change the aspect ratio, or processing such as changing the size with a black line is performed. If the vertical and horizontal sizes of the screen resolution are not divisible by 8, the same process as resizing is performed. If this processing is not performed, the processing in the DCT of J PEG will be time-consuming because of the addition of pixel complementation processing, impairing the immediacy.

In STEP 13, the area determining means 15 detects a difference area from the immediately preceding frame for each block in which the screen data is divided into blocks by blocks, and calculates a transmission area from the detected difference area. Below is the calculation of the transmission area This will be described with reference to the drawings.

FIG. 4 shows a model of a method of detecting a transmission area by dividing a screen block according to the embodiment. 1 1 is a PC having a screen. 22 is the PC screen. 23 is a block that divides the area of the PC screen by this block size. In this example, the height of the block is 1/4 of the screen resolution vertically and the width is 1/4 of the screen resolution horizontally. Reference numeral 25 denotes a difference area where a difference is detected when compared with the immediately preceding frame. In FIG. 4, the difference region 25 is distributed in a point shape as indicated by the X mark, but the difference region 25 may be distributed in a point shape, and the difference region 25 may be distributed from a plurality of adjacent pixels. It may be configured and distributed so as to have an area. Reference numeral 26 denotes a transmission area which is a minimum rectangular area including all the difference areas in one block 23.

Process screen 2 2 in block 2 3 units. In other words, the area determination means 15 compares the image data of the immediately preceding frame and the current screen data in the block 23 for each block 23, and detects the area where a difference is detected, that is, the difference area 25. I do. Then, a transmission area 26 which is a minimum rectangular area including the detected difference area 25 in one block 23 is derived. That is, the transmission area 26 calculates the minimum X coordinate and the maximum X coordinate of the difference area 25, and also calculates the minimum Y coordinate and the maximum Y coordinate of the difference area 25 at the same time. A line segment connecting the point determined by the minimum Y coordinate and the point determined by the maximum X coordinate and the maximum Y coordinate is obtained as a diagonal rectangular area.

At this time, if the area division by block 23 is not performed, if the transmission area to be transferred is calculated from the upper right and lower left coordinates of the difference area, the image data that is not the difference area, that is, image data that does not need to be transmitted, is calculated. There is a risk that the immediacy is lost and network resources are wasted.

In addition, when extracting the contours of the detected difference areas and performing grouping and combination processing in each difference area, it takes a considerable amount of time to perform calculations in performing these processing. As a result, the real-time and instantaneous properties are impaired.

Therefore, in the present embodiment, since the area determining means 15 processes the screen 22 in units of blocks 23, the above-described problem does not occur.

The STEP 14 extracts the image data of the transmission area 26 which is the smallest rectangle including the difference area 25 detected by the extracting means 16 and encodes the extracted image data. First, the extracting means 16 acquires the transmission area 26 which is the smallest rectangular area including the detected difference area 25 in the block 23, and extracts the image data of the transmission area 26 .

The image data extracted here is encoded in a form suitable for transfer. When the whiteboard data (original data before compression) is transferred as it is, the data becomes very large, requiring a long time to transfer, and occupying network resources, resulting in a heavy load on the network. Therefore, by reducing data to be transferred by compressing the data, the time required for the transfer and the load on the network can be reduced.

Regarding the form of compression, an application can be provided by selectively using lossless compression and irreversible compression of an image depending on the situation for each block 23. In the case of JPEG encoding, the compression ratio of JPEG can be changed, and it is useful to change the compression ratio according to the application, or to automatically determine the situation and change the compression ratio.

In STEP 15, the output means 17 transfers the encoded data of the screen data extracted from the transmission area 26 via the network.

In STEP 16, it is currently determined whether the block 23 that has searched, extracted, coded, and transferred the transmission area 26 is the last block. If there is a block 23 that has not been transferred yet, the processing is moved to that block 23 and the processing is performed from STEP 13. The optimal operation sequence for this block is considered to be scanning in raster order from the upper left. In STEP 17, the memory area that stores the acquired image data, the extracted image data, and the data area that has been transmitted are released. By performing this processing, the system resources on the PC 21 side can be prevented from being exhausted, and the memory can be used effectively. In STEP 18, it is determined whether or not there is an end signal from the user. If there is a signal from the user to terminate, the application must be terminated, so the process moves to termination. If there is no end signal, the processing must be continued, so the next screen data is acquired and repeated in order. If there is no signal, move the processing to STEP 11 and execute. Also, the extraction, encoding, and transfer may be performed after calculating the transmission area in all the blocks. At the time of this extraction processing, if there is a transmission area extending between blocks between adjacent blocks, one transmission area can be obtained by using the correlation between the blocks. Note that this point will be described in detail in a third embodiment described later.

As described above, in the present embodiment, the screen is divided into blocks in units of blocks, and a difference region from the previous frame is obtained in units of blocks. For this reason, since the difference regions existing at distant positions can be regarded as separate regions, transmission of a region that is not the difference region is reduced.

As described above, depending on the display format such as the projector that outputs the image, in the case of a device in which the decoded images are displayed in the scanning line order, the block is divided only in the horizontal direction. However, the screen changes smoothly. Fig. 5 shows an example of a screen when such block division is performed only in the horizontal direction.

In FIG. 5, the direction from the left to the right of the screen 22a is the direction of the scanning line. In this case, each block 23 is configured to divide a direction orthogonal to a scanning direction when the projector 112 receiving the transmitted video signal displays the video signal. That is, the horizontal length of the block 23 The length is the same as the horizontal width of the screen 22a, and the vertical length of the block 23 is a length obtained by dividing the vertical width of the screen 22a into eight equal sections. Further, in FIG. 5, 25a is a difference area, and 26a is a transmission area.

Further, in the present embodiment, the screen data is described as a video signal composed of a plurality of frames. However, the present invention is not limited to this, and the screen data is a video signal composed of a plurality of even fields and odd fields. It doesn't matter. When the screen data is a video signal composed of a plurality of even fields and odd fields, the area determining means 15 determines the predetermined even field or odd field of the video signal composed of each even field and odd field. For each block, compare those blocks with each block of the even or odd field that immediately precedes the given even or odd field corresponding to those blocks, and a rectangle containing the area of different pixel values You only have to determine the area.

Furthermore, in the present embodiment, the screen data has been described as being obtained by acquiring the video signal displayed on the screen of the PC 11 by the screen data acquiring means 14. It can be an incoming video signal.

Furthermore, in the present embodiment, the description has been given assuming that the extracting unit 16 extracts the image data of the transmission area 26 and encodes the extracted image data. However, the present invention is not limited to this. The extracting means 16 may extract the image data of the transmission area 26 and output the extracted image data to the output means 17 as it is. That is, the image data may be transmitted to the projector 12 without encoding.

Further, in the present embodiment, the output unit 17 has been described as transmitting the image data of the transmission area 26 to the projector 12, but the present invention is not limited to this. 17 may output the image data of the transmission area 26 to a recording medium such as a hard disk.

Further, in the present embodiment, the transmission area 26 is described as the smallest rectangular area including all the difference areas 25 included in one block 23. However, the transmission area 26 is not limited to this. As long as the rectangular area includes all the difference areas 25 included in one block 23, the area need not be the minimum rectangular area.

Further, the image data of the present embodiment is an example of the video signal of the present invention, the difference area of the present embodiment is an example of the area of the present invention, and the transmission area of the present embodiment is the rectangular of the present invention. It is an example of an area.

(Embodiment 2)

FIG. 1 is a diagram showing an embodiment of the system of the present invention. Reference numeral 11 denotes a PC that can transmit a signal through the interface of the Wire Ares LAN. Reference numeral 12 denotes a liquid crystal projector having a wireless LAN interface for receiving signals, decoding the received signals, and projecting the obtained image data. A screen 13 displays an image projected by the liquid crystal projector. The PC 11 and the liquid crystal projector 12 are the same as those in the first embodiment. Further, the configuration of PC 11 is shown in FIG. 3, as in the first embodiment.

In this system, PC 11 acquires the screen data displayed on the display of PC 11 or, if a secondary monitor exists, the primary monitor and / or the secondary monitor, or both. The obtained video signal is divided into blocks, this screen data is regarded as a moving image, and an area where a difference is generated by comparing with the immediately preceding frame (hereinafter referred to as a difference area) is detected. The transmission area, which is the smallest rectangular area including all the difference areas, is calculated, and the image data of the transmission area is extracted from the screen data. Go out. The extracted image data is encoded by compression or the like, and the encoded data is transmitted via the LAN interface. This operation is performed by the PC 11.

Further, the projector 12 receives a signal via the LAN interface, decodes the received signal to obtain image data, and projects the image data updated by the image data.

Also, here, the projector 12 is taken as an example, but a display device such as a CRT display plasma display, a liquid crystal display, or a DLP projector can be used instead.

In this example, the LAN interface is used. However, this LAN can be used either wirelessly or wired. In the case of a wireless LAN, it operates in either the peer-to-peer ad hoc mode or the infrastructure one mode.

Although PC 11 is taken as an example here, a terminal having a LAN interface and having screen data or a small mobile terminal such as a mobile phone may be used. In addition, as a device that generates a video signal, it acquires image data from a TV or VTR, detects and extracts a difference area from the immediately preceding frame, and extracts a transmission area that is the smallest rectangular area including the extracted difference area. It may be a small attachment part that has the function of calculating, acquiring the image data in the transmission area, encoding it, and transmitting it to the network. Also, a TV or VTR having these functions may be used. Although the LAN interface is described here as an example, an interface to a system that can construct a network such as B1 uet o o th may be used.

In the present embodiment, the area determination means 15 detects and extracts a difference area having a difference from the frame immediately before the moving image, and calculates a transmission area that is the minimum rectangular area including the extracted difference area. Is performed in block units, and the extracted transmission The output means 17 transmits only the video signal included in the area using the wireless / wired LAN.

As for the screen data acquisition, the screen data acquisition means 14 copies the screen data displayed on the PC 11 onto the main memory. At this time, the screen data is acquired collectively instead of dividing the screen data. As a result, it is possible to prevent a screen shift in which an image changes at a boundary of a segmented area of a moving screen such as a moving image. The PC 11 performs these processes.

A TV tuner, DVD player, or VTR that generates a video signal instead of PCI 1 may be used. In this case, the video signal is divided into blocks, and the difference area between the previous and next frames is detected. Calculates the transmission area that is the smallest rectangular area that includes all the difference areas included in one block, extracts the image data in the calculated transmission area, encodes it, and transmits it. It is necessary to incorporate or attach a device to perform the operation. FIG. 7 is a block diagram of the projector 112 for displaying data transferred from the PC 11 via the network. 12 is the projector body. 32 A is a memory for storing and storing transferred data, programs for processing, and the like. 32 B is a decoder for decoding the encoded and transmitted data. 32C is a projection unit for projecting the image data decoded by the decoder toward the screen. 32D is a LAN interface for receiving signals via LAN.

FIG. 6 shows the procedure of the process in the projector 12.

In STEP 21, the LAN interface 32D receives the data transmitted via the LAN and stores it in the memory 32A.

In STEP 22, the received data stored in the memory 32A is sent to the decoder -32B to decode the data. In STEP 23, the projection unit 32C displays the decoded image data on a display device.

In this system, signals are transmitted from the LAN interface 32D. At this point, encoding is performed, the image information, encoding format, and the like are determined based on the header information at the time of transmission, and the data is passed to the next processing. Details about the encode format! As for the value of / and the value, there is information in the header of the image data, but it is sufficient if there is information of which decoder 32B should decode this signal. Decoding is performed by the decoder 32B in the format indicated by the header information of the received data.

Further, it is preferable that the system be capable of performing processing in parallel with the receiving step (STEP 21) and the decoding step (STEP 22). In the display step (STEP 21), the decoded signal is written into a memory area secured as a video memory, and the obtained image data is written. When the writing is completed, a signal is sent to the display device, and the display device displays the data in the video memory.

FIG. 8 shows an example of processing in which screen data is divided into blocks in units of blocks. In this system, the processing by the decoder 32B can be performed simultaneously during the receiving step (STEP 21). This is because the chip that controls the decoder 32B and the chip that controls reception by LAN are different. In addition, even when processing is performed by the same chip, the problem can be solved by performing multi-processing processing by time-division processing such as TSS (Time Sharing System).

When the screen is divided into 4 blocks, the transmitting side detects the difference area in 1/4 screen image, calculates the transmission area from the detected difference area, encodes the detected image data, Perform transmission. For this reason, the process on the receiving side is an optional process. 51A is a receiving operation of the image data of the first block. 51B is the first block decryption process. The decoding process cannot be performed unless all signals are received. Also, in the case of transmission processing in the streaming movie format, the received data is immediately sent to the decoder and decoded while receiving.

52A is the reception processing of the second block. At this time, the processing of 51B can be performed simultaneously. 52B is the decryption of the second block.

53A is the reception processing of the third block. At this time, the processing of 53 A is performed simultaneously with the processing of 52 B.

54A is a process of receiving the image data of the fourth block. At this time, it is performed simultaneously with the processing of 53B. 54B is a fourth block decoding process. In this example, the processing time of the receiving process is longer than that of the decoding process, but in the opposite case, the received data is stored in a buffer so that the receiving process can be performed without stopping the receiving process. This system requires a device that can perform the above processing.

Note that the projector 12 of the present embodiment is not limited to the one having the above configuration and operation, and it is also possible to use a projector used in a conventional technique. In the present embodiment, only a plurality of transmission areas appear in one frame, and any projector having a function of receiving an encoded video signal in a fixed transmission area as used in the conventional technology is used. For example, it is applicable to the present embodiment.

(Embodiment 3)

In FIG. 9, reference numeral 101 denotes a PC (personal computer). The PC has a display device and displays a screen in the display device. 102 is the displayed screen. When displaying the screen continuously, 103a, 103b, 103c, 103d, 103e, 103f, 103g, and 103h are compared with the previous frame, respectively. Is the smallest rectangular area including the part that has changed from the frame of FIG. This area is also called a transmission area in the third embodiment. If the transmission area is detected within a block that divides the screen into arbitrary numbers, and transmission is performed individually, overhead will be incurred during transmission, resulting in inefficient operation. For this reason, transmission areas in adjacent blocks are grouped, and the grouping is performed. This not only reduces overhead during transmission, but also prevents display misalignment when displaying the screen on the receiving side. 1 1 1 and 1 1 2 are transmission areas 103 a, 103 b, 103 c, 103 d, 103 e, 103 f, 103 g, 103 h Is a grouped transmission area generated by grouping in this way. Hereinafter, a grouping algorithm for generating the grouped transmission regions 1 1 1 and 1 1 2 will be described. Note that the grouping algorithm is an algorithm executed by the area determining means 15 in FIG.

As shown in Figure 10, the screen is divided into blocks, and each block is named. (0, 0), (1, 0) from the upper left. Then, the transmission area is searched for each block, and if the transmission area area exists in the block on the upper side and the block on the left side, the transmission area is set as the group with the adjacent transmission area. The method of determining the rectangular coordinates at this time is such that the upper left coordinate is the minimum coordinate among the upper left coordinates of each rectangle, and the lower right coordinate is the maximum coordinate of each rectangle. Note that the origin of the coordinate system provided on the screen 102 in FIG. 9 is the upper left corner of the screen 102, the X axis is the positive direction from left to right of the screen 1◦2, and the Y axis. Means that the downward direction from the top of the screen 102 is positive.

FIG. 11 is a flowchart of this process. As a prerequisite, the number of divisions of the block is assumed to be n in the horizontal direction and m in the vertical direction (in Fig. 10, the number of divisions in the horizontal direction is 4 and the vertical direction is 4). Each block has a sig_flag indicating the presence or absence of a difference area, and the number of the group to which the block currently belongs. With par parameters. As a global parameter, the number of groups to be transmitted is included as GroupNo. When this GroupNo is 0, there is no change area, so there is no need to transmit.

STEP 301 is a step of initializing the sig-flag parameter of each block and the numper of the group. At this time, the X and Y parameters are parameters indicating the position of the block currently pointed to.

STEP 302 is a step of detecting a difference area from the immediately preceding frame in the currently indicated block and calculating a transmission area from the detected difference area.

STEP 303 is a step of performing parameter determination from the execution result of STEP 302. If there is a transmission area in this block, the process is sent to STEP 303, and if there is no transmission area, the process is sent to STEP 310.

STEP 304 is a step of inputting a value of TRUE to sig_flag because the processing result in STEP 302 is “there is a transmission area”.

STEP 305 is a step of determining parameters of a block adjacent to the right side. At this time, this processing is not performed for the block located at the right end of the screen. If the sig-flag of the block on the right is TRUE, the process is sent to STE P 306. If the sig-flag is FALSE, the process is sent to STE P 307.

STEP 306 is a step of grouping the block of interest currently and the block on the left. The grouping process registers the same group number as the block on the left in the parameters of the block, compares the group rectangle with the transmission area in the current block, minimizes the upper left coordinate, and lower right Set the value that makes the coordinates of the maximum and.

STEP 307 is a step of determining the parameters of the block adjacent to the upper side. This step has a transmission area in the block to the left This is not done in the time and block located at the top of the screen. If the sig-flag parameter of the upper adjacent block is TRUE, the process is sent to STEP 309, and if it is FAL SE, the process is sent to STEP 310. STEP 308 is a step of grouping the block of interest and the block immediately above it. At this time, the processing at the time of grouping is as follows: the same group number as the block on the upper side is registered in the parameters of the block, the rectangle of the group is compared with the transmission area of the current block 內, and the upper left coordinates Set the value where is the minimum and the lower right coordinate is the maximum.

STEP 309 is a step of generating a new group because there is no transmission area in an adjacent block. Create a new group and increment the GroupNo parameter. Then, the transmission area of the group that is currently focused on the newly created group is registered.

STEP 310 is a step to move the block of interest to the block on the right.

STEP 311 is a step of determining whether or not the block of interest is at the right end. If the target block before the change is the left end, if the parameter increment results in more than the number of horizontal divisions, there is no adjacent block on the right side. It can be determined that it was located at the left end. At this time, if the block of interest before the parameter change is located at the right end, the process is sent to STEP 312, and if not, the process is sent to STEP 302.

STEP 3 12 is a step in which the block of interest is the block at the left end below. STEP 313 is a step of determining whether or not the block of interest before the parameter is changed in STEP 313 is currently positioned at the lower end. If the increment result is equal to or greater than the number of vertical divisions, it is understood that the target block before parameter change is located at the lower end. This At the time of, when the block of interest before the parameter change is located at the lower end, the process is terminated, and when not, the process is sent to STEP 302.

This will be described with reference to FIGS. In FIG. 12, 102 is the same screen as that shown in FIG. This screen is divided into 4 x 4 blocks this time, and each block is named. Perform initialization processing and implement the grouping algorithm. First, the transmission area 103 a of the (0,0) block is calculated. At this time, the transmission area rectangle of this block is (Xi-Y

It becomes. This block generates the first group because there is no block adjacent to the block in the upward and left directions. This group is called “Group 1”. This group 1

Register. Next, look at the (1,0) block. Transmission area 1 0 3 d of the proc is (Xs- ^ Ys- - (X 2- 2, Υ 2 -. A ₂₎ for the block adjacent on the left is the presence of transmission area 1 0 3 a, left neighbor Add the transmission area of (1,0) block to the group 1 that includes the transmission area of the block of (1). The coordinates on the upper left are Xi-i <X ₂ — ₂ , Υ 1-1> Y ₂ -i, so (X ^ Yw) The lower right coordinate is X-^ Xs-

2 So, (X _₂ - _2, a Y.

The same processing is performed for the (2,0) block and the (3,0) block. Since these blocks have no transmission area, no grouping is performed. The same processing is performed in the order of (0, 1) (1, 1) (2, 1) (3, 1) (0, 2) (1, 2). In the processing for the (2, 2) block, this block has a transmission area 103e. However, there is no transmission area in the blocks adjacent to the upper and left directions, so a new group, “Group 2”, is generated. Then, when all blocks have been processed, two groups are created. The transmission rectangle is a transmission area 111 in which group 1 is grouped (Xi-i, Y-CKa-s.Yn), and a transmission area 112 in which group 2 is grouped ( X

Become. In this manner, blocks adjacent in the horizontal or vertical direction are both area determining means.

In the case of having the transmission area determined in 15 above, if a rectangular area that includes both the transmission areas of the blocks adjacent in the horizontal or vertical direction is set as a grouped transmission area, the transmission area will be over. Can be made smaller.

Also, in the above method, the transmission areas 103a, 103b, 103c and the transmission area 103d as shown in Fig. 12 are not connected, but are in the same group. It is transmitted as a grouped transmission area 1 1 1. At this time, the area between the transmission areas 103a, 103b, 103c and the transmission area 103d does not need to be transmitted, but is transmitted. The following method may be used to solve this problem.

The method is a method to determine whether the transmission area straddles the boundary between adjacent blocks. Figure 13 shows the sequence of this algorithm. In FIG. 13, STEP 501 is a step of performing an initialization process. Set all the parameters of X, Y, and GroupNo to 0, and initialize the parameters and parameters of each block.

S T E P 502 calculates the transmission area with the previous frame in the block

Step 503 is a step of detecting the presence / absence of a transmission area from the processing result of step 502 and making a determination. If the transmission area exists in the block of interest, the processing is sent to STEP 504, and if not, the processing is sent to STEP 515.

STEP 504 is a step of determining whether the transmission area in the block of interest is in contact with the boundary with the block on the right. At this time, if the transmission area is in contact with the boundary line with the block adjacent to the right side, the process is sent to STEP 505; otherwise, the process is sent to STEP 506. STEP 505 is a step of performing processing for providing a parameter indicating that the transmission area of the target block is in contact with the right boundary line. Set TRUE-parameter to Right—sig—flag of this block.

STEP 506 is a step of judging whether or not the transmission area in this block is in contact with the boundary line with the block adjacent downward. At this time, the process is sent to STEP 507 when the transmission area in this block is in contact with the boundary line with the block adjacent downward, and to STEP 508 otherwise.

STEP 507 is a step of performing processing for providing a parameter indicating that the transmission area of the target block is in contact with the lower boundary line. Set a parameter of TRUE to Bottom_sig—flag of this block.

STEP 508 is a step of judging whether or not the transmission area of the target block is in contact with the boundary with the block adjacent upward. At this time, the process is sent to STE P 509 if the transmission area in the block of interest is in contact with the boundary line with the block adjacent downward, and to STE P 511 if not.

STEP 509 is a step of judging whether this block is not located at the left end and whether the transmission area of the block on the left is in contact with the boundary line with the block of interest. At this time, if this block is located at the left end, there is no block on the left, and the process is sent to the STEP 511 without determining the parameter. Further, if the transmission area of the block adjacent on the left is in contact with the boundary line between the attention-flop lock checks Right_si _g one flag parameter of proc left adjacent, STEP 5 1 If the value of this parameter is TRUE To 0, if this parameter is FALSE, send processing to STEP 51 1.

The STE P510 connects the transmission area in the block of interest to the block on the left. This is a step of adding to the group to which the transmission area in the packet belongs. The method of adding to the group is the same as the previous method.

STEP 511 is a step of checking whether or not the transmission area in the target block is in contact with the boundary with the upwardly adjacent block. At this time, if the transmission area in this block is in contact with the boundary with the block on the upper side, the process is sent to STEP 512, and if not, the process is sent to STEP 514.

STEP 5 12 is a step for determining whether or not the current block of interest is not located at the upper end, and whether the transmission area in the upper adjacent block is in contact with the boundary line with the current block of interest. is there. Currently, if the block of interest is at the top, there is no block adjacent to the top, so there is no need to check the parameters. In this case, the process is sent to STEP 514. If this block is not located at the upper end, it is determined whether or not the difference area in the upwardly adjacent block is in contact with the boundary line with the target block using the Bottom-sig_flag parameter on the upper side. At this time, if the Bottom-sig_flag parameter is TRUE, the process is sent to STEP 513, and if it is FALSE, the process is sent to STEP 514.

STEP 513 adds the transmission area in the target block to the group to which the transmission area in the upwardly adjacent block belongs. The additional processing is the same as in the previous method.

STEP 515 is a step of moving the target block to the right block. Increment X parameter.

STEP 516 is a step for determining whether or not the value of X is equal to or greater than the number of horizontal divisions. At this time, if the value obtained by incrementing X is equal to or greater than the number of horizontal divisions, the block to be focused on before changing the parameter is the block located at the right end, so the processing is passed to the right. I can't do it. At this time, if the value of the parameter is equal to or greater than the number of divisions in the horizontal direction, the process proceeds to STEP 517.

STEP 517 is a step of performing processing for moving the processing performed to the rightmost end to the leftmost block of the next column. Increment the value of the Y parameter and set the value of the X parameter to 0.

STEP 518 is a step of determining whether or not the incremented Y parameter is equal to or greater than the number of vertical divisions. At this time, if the value of the Y parameter is equal to or greater than the number of vertical divisions, since it is located at the lowermost position, it is not possible to move the processing to the block below it. Make a determination. If the value of the Y parameter is less than the number of vertical divisions, the process is sent to STEP 502;

An example of this algorithm is shown in FIG. First, an initialization process is performed, and a difference search and a grouping process are performed from the (0, 0) block. The (0,0) block has a transmission area (X-Yi--(Χ ^, Υ) as a transmission area 103a. This transmission area 103a has a boundary with a block 103d adjacent to the right. It does not touch, but touches the border with the block 103b, which is adjacent downward.Therefore, the Bottom—sig__flag parameter of this group is set to the value of T RUE. Since there is no block in contact with the upper direction, a new group (group 1) is created, and the rectangle of the transmission area of this block is used as the group rectangle, and the process is sent to the next block. , 0) block has a transmission area (X 2-Ι, Υ 2-lHX 2-2, Y 2-2) as a transmission area 103 d.

103 d does not touch the boundary between the rightward and downward directions and the adjacent block, so there is no change in the parameters. And since this transmission area 103 d is not in contact with the boundary between the block adjacent to the upper direction and the left direction, A new group (group 2) is generated, and the transmission area 103 d of the group of interest is registered in this group. Since the (0,2) block and (0,3) block do not have a transmission area, no grouping processing is performed. (1, 0) block has a transmission area _{_{(Xi- .Y -CXi- 2, Y 2}} ) as the transmission area 1 0 3 b. Since the transmission area 103b is in contact with the boundary between the adjacent block in the downward direction, the value of the Bottom-sig_flag parameter is set to TRUE. Also, this transmission area

103 b is in contact with the border line with the block next to it. Then, since the Bottom-sig-flag parameter of the upper adjacent block is T RUE, the transmission area of the block focused on group 1 to which the transmission area 103a in the upper adjacent block belongs is added. Thereafter, this process is performed until the last (3, 3) block. _C By performing such a process, three transmission areas 1 are grouped.

1 3, 1 1 4 and 1 1 5 can be obtained.

In this way, blocks adjacent in the horizontal or vertical direction are both area determining means.

If the transmission areas determined in step 5 are in contact in the horizontal or vertical direction and the transmission areas are adjacent in the horizontal or vertical direction, the transmission areas that include the transmission areas of the blocks adjacent in the horizontal or vertical direction are grouped together. If the transmission area is set as described above, the overhead at the time of transmission can be reduced.

According to the present embodiment, for a system for transmitting screen data in real time to a display device such as a projector, a PC screen is divided into sections to process the screen data so that the difference area from the immediately preceding frame can be defined in detail. Since it can be detected, unnecessary information is not transmitted. As a result, it is possible to reduce the time required for transmission and the overall processing time in real-time transmission, reducing the load on the network, the load on the PC for transmission to the network, and It is possible to reduce the network processing on the display system side that performs reception.

Further, according to the present embodiment, screen data can be divided and transmitted in parallel. Thus, decryption can be performed while receiving. As a result, the processing time can be greatly reduced, and real-time and immediateness can be maintained.

Note that the grouped transmission areas of the present embodiment are examples of rectangular areas obtained by applying a predetermined rule from the determined rectangular areas of the present invention.

The program of the present invention is a program for causing a computer to execute the functions of all or a part of the transmitting device of the present invention, and is a program that operates in cooperation with the computer.

Further, the recording medium of the present invention is a recording medium that carries a program for causing a computer to execute the functions of all or a part of the above-described transmitting device of the present invention, and is readable and readable by a computer. The program is a recording medium that executes the function in cooperation with the computer.

The “partial means” of the present invention means one or three or more of the plurality of means.

The “function of the means” of the present invention means all or a part of the functions of the means.

Further, one use form of the program of the present invention may be a form in which the program is recorded on a computer-readable recording medium and operates in cooperation with the computer.

One use form of the program of the present invention may be a form in which the program is transmitted through a transmission medium, read by a computer, and operates in cooperation with the computer.

The recording medium includes ROM and the like, and the transmission medium includes a transmission medium such as the Internet, light, radio waves, and sound waves.

Further, the above-described computer of the present invention is not limited to pure hardware such as a CPU, but also includes firmware, an OS, and peripheral devices. You can use it.

As described above, the configuration of the present invention may be realized by software or hardware. Industrial applicability

As is apparent from the above description, the present invention provides a transmission device and an image processing system in which the amount of image data to be transmitted does not increase, the load due to traffic does not increase, and the immediacy required for real-time transmission is not impaired. , An image processing method, a program, and a recording medium.

Claims

The scope of the claims

1. For each block of a predetermined frame of the video signal composed of each frame divided into a predetermined number of blocks, the blocks and the blocks corresponding to those blocks, immediately before the predetermined frame Area determination means for comparing each block of the frame of the frame of interest and determining a rectangular area including areas of different pixel values;

Output means for outputting the video signal extracted by the extracting means.

2. For each predetermined even or odd field block of the video signal composed of each even field and odd field divided into a predetermined number of blocks, these blocks correspond to the blocks. Area determination means for comparing each block of the even field or the odd field immediately before the predetermined even field or the odd field, and determining a rectangular area including areas of different pixel values;

Output means for outputting the video signal extracted by the extracting means.

3. The predetermined rule is that when the predetermined blocks adjacent in the horizontal or vertical direction both have a rectangular area determined by the area determining means, 3. The transmission device according to claim 1, wherein the rule is a rule for generating a rectangular area including both rectangular areas of the predetermined block adjacent in the horizontal or vertical direction.

4. The region including both the rectangular regions of the predetermined block adjacent in the horizontal or vertical direction is the smallest rectangular region including both the rectangular regions of the predetermined block adjacent in the horizontal or vertical direction. 4. The transmission device according to claim 3, wherein:

5. The predetermined rule is that the predetermined blocks adjacent in the horizontal or vertical direction both have a rectangular area determined by the area determining means, and the rectangular areas are in contact in the horizontal or vertical direction. 3. The transmission device according to claim 1, wherein the rule is a rule that generates a rectangular area that includes both rectangular areas of the predetermined block adjacent in the horizontal or vertical direction.

6. The rectangular area that includes both the rectangular areas of the predetermined block adjacent in the horizontal or vertical direction is the smallest rectangular area that includes both the rectangular areas of the predetermined block adjacent in the horizontal or vertical direction. The transmitting device according to claim 5, wherein the transmitting device is:

7. The transmission device according to claim 1, wherein the extracting unit includes an encoding unit that encodes the extracted video signal.

8. Each of the predetermined blocks is configured to divide a direction orthogonal to a scanning direction when a receiving device that receives the transmitted video signal displays the video signal into zones. Transmitter according to Paragraph 1 or 2.

9. The transmitting device according to claim 1, wherein the size of each of the predetermined blocks is changed according to a screen resolution of the video signal generating device.

10. The video signal generator according to claim 1, wherein the video signal generator is a personal computer. 3. The transmission device according to paragraph 1 or 2.

11. A video signal generator for generating a video signal composed of frames divided into a predetermined number of blocks,

For each block of a predetermined frame of the video signal generated by the video signal generator, each block is compared with each block of the frame immediately before the predetermined frame corresponding to the block. A region determining means for determining a rectangular region including regions having different pixel values; (1) a rectangular region obtained by applying a predetermined rule from the determined rectangular region (2) or the determined rectangular region; A transmitting device, comprising: extracting means for extracting a video signal included therein; and transmitting means for transmitting the video signal extracted by the extracting means;

An image processing system, comprising: a receiving device having output means for outputting a video signal transmitted from the transmitting device.

12. A video signal generator for generating a video signal composed of each even field and odd field divided into a predetermined number of blocks, and a predetermined even field of a video signal generated by the video signal generator Alternatively, for each block of the odd field, the block is compared with each block of the even field or the odd field immediately before the predetermined even field or the odd field corresponding to the block, and different pixel values are obtained. Region determining means for determining a rectangular region including the region of (1), a video included in the determined rectangular region (2) or a rectangular region obtained by applying a predetermined rule from the determined rectangular region A transmitting device comprising: an extracting unit for extracting a signal; and a transmitting unit for transmitting a video signal extracted by the extracting unit. And,

A receiving device having an output unit for outputting a video signal transmitted from the transmitting device.

13. The extracting means includes encoding means for encoding the extracted video signal.

The transmitting means transmits the encoded video signal,

The image processing system according to claim 11, wherein the output unit outputs a video signal decoded by the decoding unit.

14. The image processing system according to claim 13, wherein said decryption unit and said output unit are executed simultaneously.

15. The transmitting device also serves as the video signal generating device,

The image processing system according to claim 11, wherein the receiving device is a liquid crystal projector.

16. The transmitting device also serves as the video signal generating device,

13. The image processing system according to claim 11, wherein the video signal generating device and the transmitting device are personal computers, and the receiving device is a DLP projector equipped with a network function.

17. For each block of a predetermined frame of the video signal composed of each frame divided into a predetermined number of blocks, for each block of the predetermined frame, the blocks and the predetermined frame corresponding to those blocks An area determining step of comparing each block of the immediately preceding frame with each other to determine a rectangular area including areas having different pixel values;

(1) The video signal included in the determined rectangular area (2) or a rectangular area obtained by applying a predetermined rule from the determined rectangular area is obtained. Take out step,

An output step of outputting the video signal extracted in the extracting step.

18. For each predetermined even field or odd field / red block of the video signal composed of each even field and odd field divided into a predetermined number of blocks, the blocks and their An area determining step of comparing each block of the even field or the odd field immediately before the predetermined even field or the odd field corresponding to the block, and determining a rectangular area including areas of different pixel values;

An output step of outputting the video signal extracted in the extracting step.

19. The transmitting apparatus according to claim 1, wherein each block of a predetermined frame of the video signal composed of each frame divided into a predetermined number of blocks, Area determining means for comparing each block of the frame immediately before the predetermined frame corresponding to the blocks, and determining a rectangular area including areas of different pixel values;

(1) A program for causing a computer to function as extracting means for extracting a video signal included in the determined rectangular area (2) or a rectangular area obtained by applying a predetermined rule from the determined rectangular area.

20. The transmission device according to claim 2, wherein each block of a predetermined even field or an odd field of the video signal composed of each even field and odd field divided into a predetermined number of blocks. Each time, the blocks and the predetermined even-numbered fields corresponding to the blocks are Area determination means for comparing each block of the even field or the odd field immediately before the field or the odd field and determining a rectangular area including areas of different pixel values;

21. A recording medium carrying the program according to claim 19 or 20, which can be processed by a computer.