JPH0440186A - Still picture transmitting method - Google Patents

Abstract

PURPOSE:To shorten time to transmit and display a picture by encoding data of an entire picture as a still picture and transmitting it when transmitting the still picture initially, after a second time, encoding only the prescribed partial area of the picture as an object and transmitting it so as to display the entire picture after synthesizing both of them. CONSTITUTION:When the still picture is transmitted initially, the data of the entire picture of the still picture is encoded as the still picture and transmitted. For each time when the still picture is transmitted after the second time, only a picture data d' of a prescribed area (d) is transmitted. The data of (a), (b), and (c) area except for the prescribed area, which are transmitted initially, are used, and the entire picture is displayed after synthesizing both of them. Thus, the encode processing amounts, decode processing amounts, and transmission amounts of the data after the second time are reduced so that the time to transmit and display the picture can be shortened. The prescribed area is defined as the area whose movement is relatively large in a screen, for example, as the area in which the image of a speaker appears in the screen as for a still picture video telephone or the like.

Description

[Detailed Description of the Invention] [Summary] Regarding a still image transmission method in which a target image is repeatedly captured as a still image, encoded and transmitted, and decoded and displayed on the receiving side, the transmission time and display time are In a still image transmission method, the target image is repeatedly captured as a still image, encoded and transmitted, and decoded and displayed on the receiving side. , during the first still image transmission, the first step is to encode and transmit the data of the entire still image as a still image, and in the second and subsequent still image transmissions, a predetermined part of the target image is encoded and transmitted. A second step is performed in which the image data of only the region is encoded as a still image and transmitted. On the receiving side, when receiving the first still image, the data of the entire still image is received, decoded, and then transmitted. In the third step of displaying, the fourth step of storing data of an area other than the predetermined partial area among the entire image data of the first still image, and the second and subsequent still image reception, a fifth step of receiving and decoding only the data of the predetermined partial area; a sixth step of reading out the stored data for the image of the predetermined partial area; A seventh method that displays the entire still image by combining the decoded data of the partial regions.
and the following steps.

[Industrial Application Field] The present invention relates to a still image transmission method in which a target image is repeatedly captured as a still image, encoded and transmitted, and decoded and displayed on a receiving side.

In a still image videophone or the like, an image of a caller is captured as a still image at predetermined time intervals, encoded, and transmitted, and the receiving side repeatedly receives, decodes, and displays the image.

However, in the encoded transmission of still images, the number of encoded pixels is generally large, and the time for transmitting and displaying one still image is long. Therefore, in the above methods, it is a problem to shorten the transmission time and display time of still images.

[Prior art and problems to be solved by the invention] Conventionally, an image of the above-mentioned object is captured as a still image,
In still image transmission methods that repeatedly encode and transmit, then decode and display on the receiving side, the entire target image is newly captured and encoded as a still image for each repetition of the still image transmission method. , and on the receiving side, the data of the entire still image was decoded and displayed each time. However, in the transmission of still images, since the amount of information to be transmitted is large, it is necessary to perform frame encoding several times, resulting in a problem that the transmission time and display time become extremely long.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a still image transmission method that reduces transmission time and display time.

[Means to solve the problem]

FIG. 1 is a diagram showing the basic procedure on the transmitting side of the still image transmission method of the present invention.

As shown in FIG. 1, on the transmitting side, when transmitting a still image for the first time, there is a first step 1 in which data of the entire still image is encoded and transmitted as a still image; In still image transmission, a second step 2 is performed in which image data of only a predetermined partial area of the target image is encoded as a still image and transmitted.

FIG. 2 is a diagram showing the basic procedure on the receiving side of the still image transmission method of the present invention.

As shown in FIG. 2, on the transmitting side, when receiving the first still image, a third step 11.12 of receiving, decoding and displaying the data of the entire still image; A fourth step 13 of storing data of an area other than the predetermined partial area out of the data of the entire still image of the still image; a fifth step 14 of receiving and decoding; a sixth step 15 of reading out the stored data for the image of the predetermined partial area; and decoding the read data and the data of the partial area. A seventh step 16 is performed in which the entire still image is displayed by composing the images.

[Effect]

According to the present invention, in each still image transmission method from the second time onward, only the image data of the predetermined area is transmitted, and the data of the area other than the predetermined image area is the same as that transmitted the first time. Since both are combined and displayed, the amount of encoding processing, decoding processing amount, and
Since the amount of transmission is reduced, transmission time and display time are shortened. The predetermined area mentioned above is an area where there is relatively large movement within the screen, for example, in a still image videophone, the area where the image of the caller appears on the screen, and the background area does not change. If it is assumed that the change is likely to be the same, or if there is a change, it is not important, then as described above, when displaying the still image from the second time onwards, the one transmitted the first time is used.

〔Example〕

FIG. 3 is an explanatory diagram of the procedure of the first still image transmission in the still image transmission method of the present invention.

As shown in FIG. 3, the entire screen area is divided as shown by dotted lines in FIG. 3, and the data in each partial area is designated as a, b, c, and d. Here, for example, the partial area of data d corresponds to the above-mentioned predetermined area. At that time, the entire image data a is transmitted by the first still image transmission.

When data b, c, and d are encoded and transmitted, they are decoded and displayed on the receiving side, but among these, partial area data a, b, and C are stored in memory. .

FIG. 4 is an explanatory diagram of the procedure for second and subsequent still image transmissions in the still image transmission method of the present invention. As shown in FIG. 4, the still image data captured on the transmitting side is divided into data a, data a,
b, c, and d are respectively a', b', C'l
and d', according to the present invention, only the data d' of the partial area corresponding to the partial area of d is encoded and transmitted from the transmitting side. And the above a
, b, and C, the data a, b, and C transmitted and stored at the first time are used for the second and subsequent still image displays, and these are combined to create the image shown in FIG. Display a still image as shown on the right side of .

FIG. 5 shows the configuration of an embodiment of the present invention. In the example of FIG. 5, among the partial areas divided as described above (FIGS. 3 and 4), a partial area (of the data a, b, c) to be displayed using data stored in the memory is used. (area), in addition to using the data transmitted the first time as described above, it is also possible to combine and display charts, photographs, etc. To this end, in the configuration shown in FIG. 5, data that can be displayed in the display partial area using the data stored in the memory described above is stored in a plurality of memory areas 31, 32, 3.
3, and one is selected by the selector 34 at the time of composite display.

〔Effect of the invention〕

According to the still image transmission method of the present invention, it is possible to particularly shorten the transmission time and display time when repeatedly transmitting images of the same object.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the basic procedure on the transmitting side according to the present invention, Fig. 2 is a diagram showing the basic procedure on the receiving side according to the present invention, and Fig. 3 is a diagram explaining the procedure of the first still image transmission according to the present invention. , FIG. 4 is an explanatory diagram of the procedure for second and subsequent still image transmission according to the present invention, and FIG. 5 is a diagram showing an embodiment of the present invention. Diagram J showing the basic procedure on the transmitting side according to the present invention. Memory clear diagram illustrating the procedure for the first still image transmission according to the present invention'! Figure 3: Information on previous still image encoding stored in memory Figure 4: Diagram illustrating the procedure for second and subsequent still image transmission according to the present invention Figure 4: Diagram showing the basic procedure on the receiving side according to the present invention Figure 4: Information on previous still image encoding stored in memory Figure 5 showing an example

Claims (1)

[Claims] 1. In a still image transmission method in which a target image is repeatedly captured as a still image, encoded and transmitted, and decoded and displayed on the receiving side, the transmitting side When transmitting an image, the first step (
1), and a second step (2) of encoding and transmitting image data of only a predetermined partial area of the target image as a still image in the second and subsequent still image transmissions, and the receiving side When receiving the first still image, the third step (11) is to receive the entire still image data, decode it and display it.
, 12), a fourth step (13) of storing data of an area other than the predetermined partial area among the entire image data of the first still image, and in receiving the still image from the second time onwards, a fifth step (14) of receiving and decoding only the data of the predetermined partial area; and a sixth step (15) of reading out the stored data for the image of the predetermined partial area; A still image transmission method, characterized in that a seventh step (16) of displaying the entire still image by composing the read data and the decoded data of the partial area is performed.