CN1290107A

CN1290107A - Method for implementing picture-in-picture mode at remote end

Info

Publication number: CN1290107A
Application number: CN 99124655
Authority: CN
Inventors: 郭宏智; 邹孟睿; 火焰; 黄强
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 1999-12-18
Filing date: 1999-12-18
Publication date: 2001-04-04
Anticipated expiration: 2019-12-18
Also published as: CN1148062C

Abstract

A method for implementing the remote picture-in-picture of video meeting is disclosed, which includes such steps as converting the image taken by master comera to data in CIF format, converting the images taken by secondary cemeras to small images to be overlapped, overlapping them in video overlapping module to obtain a frame of image data in CIF format, encoding and transmitting to channel via multiplexer module.

Description

The implementation method of far-end picture-in-picture

The invention belongs to electrical communication technology, be specifically related to the video conferencing field.

In TV conference system, the terminal in a plurality of meeting-place of multipoint control unit (MCU) below network control, the terminal in each meeting-place have the function that sends this client information and receive the other side's information simultaneously.Generally speaking, each terminal also will show the image an of width of cloth this locality when receiving the other side's image, and promptly local picture-in-picture, this image generally are the images of local main camera.

Generally, the main meeting-place is an auditorium that can hold the hundreds of people, because the meeting-place is too big, a video camera can't all be taken into the scene in whole meeting-place, so can arrange the video camera more than two or two, a video camera is taken the picture on the rostrum, the picture on remaining video camera shooting auditorium etc.

As shown in Figure 1, the terminal equipment in each meeting-place can connect a plurality of video cameras, terminal equipment not only needs to transmit the image of main camera, also requirement can transmit the image of one or more auxiliary cameras (as: picture and text video camera), the image that transmits is many more, and the information that the other side obtains is also just many more.At present to this problem, video conferencing both domestic and external manufacturer adopts the method in Switch Video source to make to can seeing the image of other video cameras picked-ups, but this method synchronization can only transmit the image of a video camera picked-up.When meeting is carried out, switch two video source in same meeting-place as required, make the participant in other meeting-place can see the scene in whole meeting-place.

The objective of the invention is to propose a kind of implementation method of far-end picture-in-picture, can overcome the above-mentioned shortcoming of existing technology, make the both sides of meeting both remove the trouble of wanting frequent Switch Video source from, can see the image of two or more scenes of the other side again simultaneously.

The notion of far-end picture-in-picture proposes with respect to local picture-in-picture.That is to say, can see the picture more than three on each terminal of far-end picture-in-picture TV conference system simultaneously, the master image that piece image sends over for the other side, another width of cloth is the local picture-in-picture that is superimposed upon on the master image, also has a width of cloth or is superimposed upon the far-end picture-in-picture that sends over from the other side on the master image more than the width of cloth.

Method of the present invention is to realize by following technical scheme: the image of main camera picked-up is converted into the desired standard data of encoder earlier by format converting module, as: CIF (public intermediate form), QCIF (CIF 1/4th); The image of a plurality of auxiliary camera picked-ups is converted into the little image that needs stack by format converting module respectively; Then master image is sent into the video superimpose module together with the little image that needs stack and superpose, become the desired standard data of a frame encoder; Give encoder again and do coding; Data behind the coding are served channel through Multiplexing module.

Method of the present invention has realized that video conference terminal equipment transmits the motion video image of two or more video camera picked-ups simultaneously, when holding video conference, the recipient of meeting can see the image of two or more scenes of the other side simultaneously, has promptly realized the far-end picture-in-picture; Also saved simultaneously the trouble in Switch Video source.

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

Fig. 1 is the connection diagram of video conference terminal video camera in the prior art;

Fig. 2 is the schematic flow sheet of video conference terminal image encoding in the prior art;

Fig. 3 is to be the application examples of the present invention of example with two video source;

Fig. 4 (a) is the stack schematic diagram of brightness signal Y in the video superimpose process;

Fig. 4 (b) is the stack schematic diagram of carrier chrominance signal U in the video superimpose process;

Fig. 4 (c) is the stack schematic diagram of carrier chrominance signal V in the video superimpose process.

Fig. 1 is the description to the connection situation of video conference terminal video camera in the prior art, has done detailed introduction in the background technology in front.

Fig. 2 is the video conference terminal image encoding schematic flow sheet of prior art, in the prior art, video conference terminal image encoding process is as shown in Figure 2: be analog video signal the form of standard by the format conversion module converts at first, as: CIF (public intermediate form), QCIF (CIF 1/4th) form, give encoder then and do coding, the data behind the coding are through the multiplexing channel of serving.This mode obviously only is suitable for synchronization and transmits piece image.

Fig. 3 is to be example to connect two video source, and the implementation procedure of the inventive method has been described:

Video source 1 is the image of main camera picked-up, be converted into the desired formatted data of encoder earlier by format converting module, as: CIF (public intermediate form), QCIF (CIF 1/4th) formatted data, video source 2 is the image of auxiliary camera picked-up, is converted into the little image that needs stack by format converting module; Then master image is sent into the video superimpose module with the little image that needs stack and superpose, the synthetic desired formatted data of a frame encoder, as: the view data of CIF, QCIF form; Give encoder again and encode, here, the little image that needs stack is that the size and the position of far-end picture-in-picture can be provided with according to client's demand.For encoder, therefore image after the stack and the view data of having only piece image originally just can not influence speed of coding and effect without any difference; Data behind the coding are served channel through Multiplexing module.Compare with video conference terminal image encoding process in the prior art of Fig. 2, the present invention had increased this step of video superimpose before common image encoding.

Fig. 4 is to be the specific implementation process that example has illustrated video superimpose with two video source: piece image is made up of the several rows pixel, each pixel generally comprises a brightness signal Y and two carrier chrominance signal U and V, because human eye is not very sensitive to carrier chrominance signal, and it is relatively more responsive to luminance signal, therefore, the less carrier chrominance signal of general extraction is encoded, and has so both reduced the operand of image encoding, and being unlikely again influences picture quality.For example the pixel of the CIF image of YUV420 form is Y:352 * 288, U:176 * 144, V:176 * 144.

Among Fig. 4, the form that carries out the video source 1 of video superimpose is: YUV420, CIF, (be Y:352 * 288, U:176 * 144, V:176 * 144), carry out the video source 2 of video superimpose, promptly the form of far-end picture-in-picture is: YUV420, and 100 * 80 (is Y:100 * 80, U:50 * 40, V:50 * 40).Suppose that the user wishes the far-end picture-in-picture is placed the position of screen (200,100), additive process is as follows so:

(1) stack of brightness signal Y shown in Fig. 4 (a): find out the brightness signal Y 1 that video source 1 is positioned at 200＜x＜300,100＜y＜180, this regional luminance signal replaces with the brightness signal Y 2 of video source 2.Wherein, Y1 and Y2 are respectively the luminance signal of video source 1 and video source 2 collections;

(2) stack of carrier chrominance signal U shown in Fig. 4 (b): find out the carrier chrominance signal U1 that video source 1 is positioned at 100＜x＜150,50＜y＜90, this regional carrier chrominance signal replaces with the carrier chrominance signal U2 of video source 2.Wherein U1 and U2 are respectively the carrier chrominance signal of video source 1 and video source 2 collections;

(3) stack of carrier chrominance signal V shown in Fig. 4 (c): find out the carrier chrominance signal V1 that video source 1 is positioned at 100＜x＜150,50＜y＜90, this regional carrier chrominance signal replaces with the carrier chrominance signal V2 of video source 2.Wherein, V1 and V2 are respectively the carrier chrominance signal of video source 1 and video source 2 collections;

So far, the video superimpose process finishes.

Because the present invention has used the method for video superimpose, make the both sides that have a meeting can see two or more scenes of the other side simultaneously, can realize the transmission of far-end picture-in-picture, easy to use.

Claims

1, a kind of implementation method of far-end picture-in-picture may further comprise the steps:

1) image that main camera is absorbed is converted into and meets the formatted data that encoder requires;

2) image of a plurality of auxiliary camera picked-ups is separately converted to the little image that needs stack;

3) the little image that described master image and need are superposeed is sent into together and is carried out video superimpose, becomes frame symbol

Close the formatted data of encoder requirement;

4) view data after the stack is encoded;

5) data behind the coding are through serving channel after multiplexing.

2, the implementation method of a kind of far-end picture-in-picture as claimed in claim 1 is characterized in that: described video superimpose process comprises the stack of brightness signal Y, the stack of carrier chrominance signal U and the stack of carrier chrominance signal V:

Need at first to determine the original position of little image in big image of stack; According to the original position and the size of little image, find out the zone of little image in big image then; To be positioned at the brightness signal Y of the big image in this zone at last, carrier chrominance signal U, V use the brightness signal Y of little image respectively, carrier chrominance signal U, and V replaces.