CN1746839A

CN1746839A - Method for displaying and playbacking content of local computer on far-end computer

Info

Publication number: CN1746839A
Application number: CN 200510104936
Authority: CN
Inventors: 张震
Original assignee: WANGTI SCIENCE AND TECHNOLOGY DEVELOPMENT Co Ltd BEIJING
Current assignee: WANGTI SCIENCE AND TECHNOLOGY DEVELOPMENT Co Ltd BEIJING
Priority date: 2005-09-22
Filing date: 2005-09-22
Publication date: 2006-03-15
Anticipated expiration: 2025-09-22
Also published as: CN100337190C

Abstract

A method for displaying and playing back display content of local computer on remote computer includes providing operation command to local computer operation system by application program, dividing operation command to form display command, calling virtual video card interface corresponding to command and sending command to remote computer, carrying out Flash format conversion and storing it to be Flash stream file as well as displaying and playing it back on screen when display command is received by remote computer.

Description

The method that on far-end computer, the local computer displaying contents is shown playback

Technical field

The present invention relates to a kind of method that on far-end computer, the local computer displaying contents is shown playback, particularly a kind of by computer network, the image on the computer screen is sent to the method that the display screen of other far-end computers shows in the network.

Background technology

Along with the development of computer communication technology, the method for utilizing computing machine to carry out long-distance education has obtained to use widely.Long-distance education is a kind of form of teaching that Faculty and Students separate, for the lecture contents with the teacher is transferred to the student, teacher's lecture contents must be saved as courseware, the mode by Network Transmission arrives student's end, and the student comes learning knowledge by the courseware of watching the teacher.

What the teacher taught most of employing is PPT manuscript or other desktop operated.It is synthetic that video, sound and the desktop operating information that courseware development must be gathered the teacher carries out technology, finishes a complete courseware.Here just relate to the collection and the transmission of teacher's presentation screen information, complete, clear, the smoothness of screen message is the key of making the high-quality course.

Normally be converted into the FLASH file after the screen message collection is come, reproduce teaching process at that time.

In existing courseware development process, usually needing screen message with teacher demonstration to be transferred on the computing machine of far-end preserves or direct viewing for downloading, in traditional screen message transmission and recording process, what the information change record of teacher's screen adopted is that screen message is saved as many images, contrast difference according to the front and back image relatively transmits the image that changes then, only transmit the rectangle information of changing unit, and mouse message.

Such as being 16 * 16=256 piece with whole teacher's screen divider, through contrast, before and after variation between adjacent two images only be present in wherein 3 blocks of little images, computing machine just only transmits 3 view data that change so, 3 image overlay with last image and back variation after REMOTE MACHINE receives obtain a back image, and the process that then adds up to change stores.

The benefit of existing this image transfer method is exactly that the technological development ratio is easier to realize, but also has some defectives and deficiency simultaneously, is specially:

1) effect of the obtain manner of image influence broadcast

The obtain manner of this image needs computer CPU contrast images constantly, the difference of two images before and after calculating, expend a large amount of cpu resources and time like this, under the relatively poor situation of machine performance, can cause other to use operation and slowly make the teacher hold computer speed to reduce inconvenient operation normally; Variable quantity obtains new images and also will consume cpu resource and far-end computer also needs constantly to superpose, and influences result of broadcast.

2) bandwidth occupancy is had relatively high expectations

Because transmission all is view data, data volume is very big, makes the requirement of the network bandwidth also than higher, is suitable for broadband environment and uses.If the bandwidth condition deficiency then can cause network congestion, influence result of broadcast.

3) image fault

Teacher's screen message is vector data originally, and zooming in or out to influence the sharpness of screen, still, has just lost the characteristic of its vector after saving as image.On-screen data is when being converted to Flash, because screen message has become piling up of various view data, comprise font, curve, information such as straight line all are that the mode with view data realizes, the Flash file that make to generate does not have vectorial property, when the playback of teaching process, amplifies and dwindles the serious distortion that all can cause image.Fig. 1 is the original vector file before transmitting; Fig. 2 is that source document is at the design sketch that saves as on the far-end computer after the later non-vector file of picture amplifies; Fig. 3 is that source document is at the design sketch that saves as on the far-end computer after the later non-vector file of picture dwindles.As can be seen, prior art makes the original vector file that amplifies on far-end computer or dwindle that serious distortion take place from three figure.

In recent years, along with the development of virtual unit technology, the application of virtual video card Driving technique, making to address the aforementioned drawbacks with deficiency becomes possibility.

Summary of the invention

The objective of the invention is at existing defective of above-mentioned existing image transfer method and deficiency, and a kind of method that the local computer displaying contents is shown playback on far-end computer is provided, this method shows the far-end computer that the image idsplay order of image transmitting terminal is sent to reception, has reduced resource occupation, solved problem of dtmf distortion DTMF.

For achieving the above object, the present invention has adopted a kind of method that the local computer displaying contents is shown playback on far-end computer, carries out following steps:

Application program on step 1, the local computer is submitted to operating system on the local computer with operational order;

Step 2, described operating system are decomposed described operational order, form the screen display instruction, and call described screen display and instruct the interface of pairing virtual video card;

Step 3, the screen display instruction after decomposing described in described virtual video card driven are sent to far-end computer;

Step 4, described far-end computer receive the screen display instruction after the described decomposition, it is carried out the Flash format conversion, and be stored as the Flash stream file, show playback on the display screen of far-end computer.

By above technical scheme as can be known, the present invention is by catching the various idsplay orders of operating system at transmitting terminal, image operation relatively before and after having reduced, it is less to take computer CPU, improve the usability of class preparation system, simultaneously, be the basic display instruction and data of compression owing to what in transmission course, send, so can reduce bandwidth occupancy greatly; Adopt this method, make vectorial property obtain keeping, dwindling or amplifying to influence the reproduction of screen effect.

Below in conjunction with drawings and Examples, technical scheme of the present invention is described in further detail.

Description of drawings

Fig. 1 is an original vector file in the background technology

Fig. 2 is the design sketch that saves as in the background technology after the later non-vector file of picture amplifies;

Fig. 3 is the design sketch that saves as in the background technology after the later non-vector file of picture dwindles;

Fig. 4 is a process flow diagram of using the embodiment of the invention;

Fig. 5 is the Flash vector transition diagram of font;

Fig. 6 is the Flash vector transition diagram of straight line.

Embodiment

Below, in conjunction with specific embodiments and with reference to accompanying drawing, the present invention is described in further detail.

Be illustrated in figure 4 as embodiments of the invention, concrete steps are:

Step 401, at transmitting terminal, application program submits to all operational orders to give operating system;

Step 402, the instruction of operating system operation splitting form the screen display instruction.Under Windows operating system, computer display card drive the basic drawing for order interface need at least to realize (GraphicsDevice Interface, GDI) as follows: as to draw, copy figure, fill path, grid fill, draw straight line, trace, the filling of closed curve path, window stretching, literal, transparency etc.Simultaneously, because the raising of computer display card technology, except basic demonstration drawing for order, in order to quicken to handle the graphic presentation and the computing of various effects, formed the graphic accelerating interface of the two big systems of DirectX and/or OpenGL again, can directly handle atomizing, have an X-rayed, tremble look figures effect.These video cards can be a large amount of the processing of reduction CPU.

Step 403, operating system are called corresponding virtual video card and are driven, and the instruction of the screen display after will decomposing all sends to the virtual video card driving;

Step 404, the logical data that virtual video card is obtained compress storage;

Step 405, logical data is sent to far-end computer by network, write down and change at the logical data type obtaining data terminal;

Step 406, far-end computer are stored as data streaming file with logical data, execution in step 409;

After step 407, far-end computer decompress logical data, also can carry out the Flash conversion to it;

Step 408, the operational order after will changing are stored as the Flash stream file;

Step 409, far-end computer according to the Flash stream file or the data streaming file after decompressing show playback.

Operational order after the virtual video card compression can also can store hard disk into for resetting in the future by Network Transmission to far-end computer.

In the realization of virtual driving, realized DirectX if drive, the interface of OpenGL, application program will directly be called these interfaces so, not realize these interfaces if drive, and application program will be called virtual video card by computing machine GDI so.

At receiving end, receive operational order after, it is resolved, just obtained corresponding operation logic structure, can correspondingly be converted into the Flash form to these logical datas.Main type has in the logical data of screen message: font, and straight line, curve, fill in the path, and grid is filled, and draws etc.These types all have correspondence in Flash.Such as: the operational order that obtains is the body of making one's cross, like this in the Flash stream file just with font type and calligraphy and painting in the fontlib of Flash file, run into the word of identical font type again next time like this, just can directly call, need not draw again again one time, as shown in Figure 5; For drawing straight line, curve, Lu Jing etc., need only obtain 2 points of straight line, the tracing point in path, the corresponding vector graphics that just can draw in the Flash stream file comes, as shown in Figure 6.

What obtain in the Flash stream file like this, has been exactly the figure of vector.Font wherein, image and various idsplay orders etc. all pass through drawing for order corresponding among the Flash to be realized, make that the file of far-end computer storage is little a lot of with respect to the method for whole employing images, simultaneously since in the data except a spot of view data, menu, a large amount of word content such as window directly is exactly to reproduce original information, make when showing playback, amplify or dwindle the effect that can not influence image with Flash.

It should be noted last that, above embodiment is only unrestricted in order to technical scheme of the present invention to be described, although the present invention is had been described in detail with reference to preferred embodiment, those of ordinary skill in the art is to be understood that, can make amendment or be equal to replacement technical scheme of the present invention, and not breaking away from the spirit and scope of technical solution of the present invention, it all should be encompassed in the middle of the claim scope of the present invention.

Claims

1, a kind of method that on far-end computer, the local computer displaying contents is shown playback, wherein, carry out following steps:

Step 2, described operating system are decomposed described operational order, form the screen display instruction after decomposing, and call the interface that the pairing virtual video card of described operational order drives;

Step 3, described virtual video card drive the instruction of the screen display after the described decomposition are sent to far-end computer;

2, the method that the local computer displaying contents is shown playback on far-end computer according to claim 1, wherein, the interface in the described step 2 comprises pattern manipulation interface and/or graphic accelerating interface.

3, the method that on far-end computer, the local computer displaying contents is shown playback according to claim 1 and 2, wherein, before the screen display after described decomposition instruction is sent to far-end computer, also be provided with the operation that processing is compressed in to the screen display after described decomposition instruction in the described step 3; In the described step 4, after the screen display instruction of described far-end computer after receiving described decomposition, also decompression operation is carried out in instruction to the screen display after the described decomposition.

4, the method that on far-end computer, the local computer displaying contents is shown playback according to claim 1, wherein, in the described step 4, after described far-end computer receives screen display instruction after the described decomposition, it is stored as data streaming file, and on the display screen of far-end computer, shows playback.