JPH01126892A - Transmitting method for color picture - Google Patents

Abstract

PURPOSE:To shorten the visual waiting time of a picture by converting a color picture signal photographed by a color television camera to a digital signal, decomposing to the luminance signals of plural steps and transmitting to a remote place. CONSTITUTION:The picture signal from the television camera 2 is converted in an A/D converting circuit 3, stored in first and second V-RAMs 5, 6 through digitizing circuit 4 and the picture signal at that time is not only decomposed to R, G, B but also a brightness is decomposed to four steps and stored. The color picture signal stored in the first and the second V-RAMs 5, 6 is transmitted for every brightness. Then, a rough entire image is reproduced initially, and as the picture signals decomposed to the four steps of a high brightness to a low brightness are sequentially fed and superposed, a fine image is gradually completed. Thereby, the visual waiting time is shortened to transmit the color picture to the remote place.

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention is a method for transmitting color images in non-store sales, catalog sales, etc., which reduces visual waiting time and enables transmission of color images to distant locations. It is related to.

"Conventional technology" Conventionally, as a technology for transmitting one image to a remote location using digital communication, the image is A/D converted, the obtained digital information is sent to the remote location via a telephone line, and the receiving side performs D/A conversion. There is a so-called facsimile machine that reproduces images.

``Problems to be solved by the invention'' Conventional facsimile machines have only two gradations, black and white, and cannot reproduce images with intermediate gradations. Second, the image can be reproduced using the received data, but the data cannot be stored in memory and used. Third, it is impossible to reproduce a good image.
Another problem is that it takes time to transmit a color image signal, and the waiting time until the image is completed is extremely long.Fourth, only information that has been printed or written on a flat sheet of paper can be transmitted.

The present invention aims to solve these problems.

The present invention digitally processes one screen of image data taken with a color television camera, and decomposes each color signal component into multiple levels of brightness and stores them in a video memory. However, in this method, the color image signal stored in the video memory is transmitted for each luminance.

``Operation'' Analog image signals taken with a color television camera are converted into digital signals and stored in video memory (V-RA).
M). At this time, one image signal is R, G, B
Each color signal is decomposed into four levels of luminance signals and stored in memory. When the modem is switched to the image communication side by a command from the CPU of the personal computer, of the image signals stored in the V-RAM, for example, only the signals for one screen of the highest brightness R, G, and H will be transmitted through the communication line. It is sent to a remote computer via the computer. On the receiving side, the sent high-brightness image signal for one screen is temporarily stored in V-RAM, sent to the palette circuit, further converted to an analog signal by the D/A conversion circuit, and sent to the 4G TV receiver. indicate. At this point, only a rough overview is reproduced, but the waiting time is perceived to be shorter than if the screen were not reproduced at all. Image signals decomposed into four stages from high brightness to low brightness are sent in sequence, and as they are superimposed, a finer and finer image is gradually completed. Note that a color image of 4096 colors can be obtained by combining four levels of brightness.

"Example" An embodiment of the present invention will be described below with reference to FIG.

( ]) is a television receiver, and a television camera (2) is connected to this television receiver (1), and A that converts the analog image signal captured by this television camera (2) into digital. /D conversion circuit (3), digitizing circuit (
4) First and second V-RAMs as video memories
(5) (6) are combined. These first and second V-RAM (s) (6) are pallet circuits (7),
The television receiver (1) via the D/A conversion circuit (8)
is combined with

Next, (9) is a floppy disk that stores computer programs, and this disk (9) is a deck (1
0) to the deck controller (11);
This deck controller (11) is the main CPU (
12), main RAM (13), and serial controller (14). In addition, the main CP
U (12) and main RAM (13) are connected to the first. Second V-
RAM (5) (6) and sub-CPU (16) are combined, and this sub-CPU (16) is connected to encoder (17).
) to the keyboard (18).

The serial controller (14) is a modem for modulation and demodulation (
19) to the communication line (20);

A telephone set (21) is coupled to this modem (19).

The communication line (20) can be a private line as well as a public line such as a telephone line.

Next, the operation will be explained with reference to flowcharts shown in FIGS. 2 and 3.

In Figure 2, turn on the power and start.

Perform initialization and internal settings for each device. next,
A menu is displayed on the television receiver (1), and the operator makes menu selections such as transmission and reception. keyboard (18)
When auto dial is selected, a call is made to the other party. That is, the modem (19) is controlled via the serial controller (14) in response to a command from the main CPU (12) to auto-dial to a pre-registered destination. If maintenance is selected, the recipient's name, phone number, etc. can be registered or edited. If you select image sending/receiving, the image taken by the television camera (2) will be sent or received.

The operation of this communication will be explained in more detail.

When the operator selects transmission using the keyboard (18), the television camera (2) continues to capture images until the capture end key is pressed.

The image signal from the television camera (2) is converted by an A/D conversion circuit (3) and sent to the first digitization circuit (4).
, 2nd (7) V-RAM (5) (6) Nimemo IJ Sarel.

At this time, the image signal is R9G, as shown in FIG.
In addition to being decomposed into H, each brightness is decomposed into four levels (numbered 3, 2, and 1.0 in order from highest to lowest brightness) and stored in memory. That is, the first (7) V-
RAM (5) contains B3. B2. R3, R2, G3. G
2 is stored in memory, and the second V-RAM (6) stores Bl, B
O, R1, RO, Gl, GO are memorized. When the capture of one screen's worth of memory is completed and the capture end key is pressed and the result becomes YES, the process remains on standby unless the cancel key is pressed.

When the send key is pressed and the result is YES, the call mode changes to the communication mode.0 When the communication mode is reached, the first and second v
- From RAM (5) and (6), high-luminance R3, G3. The B3 image signal is read out, and the read data is thinned out and compressed every other bit to reduce the transmission time. However, compression is not an essential requirement of the present invention.
Transmission data is created by combining several lines (for example, 16 lines (8 lines when uncompressed)) of each B into one. At the same time, a control signal is output from the serial controller (14) based on a command from the main CPU (12), and the modem (]G9 connects the communication line (20) to the PC main body for PC communication.Then, the image data is transferred to the other party. Send to.

As shown in FIG. 5, the television receiver (1) displays a mark (22) indicating how far on the screen the signal has been received.

If one screen has 152 lines, 16 lines are sent at one time, so the marks (22) for each 16 lines...
・Display. After transmitting 16 lines 9.5 times, the transmission of one high-brightness screen is completed and a rough screen is displayed. R
3, G3. When one screen of B3 is completed, the brightness read from the first and second V-RAM (5) (6) is changed, and the brightness read from R2, G2. One screen of B2 is transmitted and superimposed on the previous high-brightness screen. Thereafter, R1, Gl, Bl are transmitted in the same way, and finally RO, Go, BO
is transmitted, a detailed screen is formed, and the transmission ends.

Next, when the operator presses the receive key of the transmit/receive keys, the high-intensity R
3, G3. B3 data is received and input via the modem (19) and serial controller (14). If the data is compressed every other bit, the main CPU (12) decompresses and reproduces the data. The reproduced image data is written to the first and second V-RAMs (5) and (6),
Eight lines are displayed on the TV receiver (1), and the first line is displayed on the TV receiver (1). 2nd (7) V-RAM (5) (6) R3, G3
When writing for one screen of B3 is completed, a rough overall image is reproduced on the television receiver (1). Then R2゜G
2. Change to B2, write one screen, overlap the previous image, and reproduce it in slightly more detail. Similarly, 1 of R1, Gl, Bl
When the screen portion is superimposed and finally one screen portion of RO, Go, and BO is written to complete the full brightness portion, a detailed image is reproduced on the television receiver (1).

During playback, the 4-level signal is output to 409 in the palette circuit (7).
After being combined into six color image signals, it is converted into an analog signal by a D/A conversion circuit (8) and sent to a television receiver (1).
) is displayed.

Next, HDLC (High
Level Date Link Control P
rocedures) method is adopted.

The features of this HDLC are as follows.

(1) In the basic procedure, there are restrictions on the information to be transmitted, and there is a lack of independence between transmission control and terminal control. In contrast,
In HDLC, transmission is bit-oriented, and transmission control and information are completely independent, and it is possible to transmit information of any bit pattern and any number of bits.

(2) In the basic procedure, so-called alternate monitoring transmission is performed. On the other hand, in HDLC, numbers are assigned to frames corresponding to blocks in the basic procedure, and up to the next 7 (255 in extended mode) frames can be postponed before confirming the response to one frame. You can respond to them all at once. Furthermore, it is possible to add an acknowledgment response to the frame received from the other station to the information frame, resulting in extremely high transmission efficiency.

(3) In the basic procedure, response codes and supervisory codes (ACK) are used.
, NAK, ENQ, etc.), but in HDLC, CRC (Cyclic Redundancy Clock, etc.) is attached to all frames.
heck) bit is added to ensure high reliability of transmission.

(4) Full-duplex communication cannot be performed on a branch line in the basic procedure, but it is possible in HDLC.

(5) In HDLC, the frame format is unified and conceptually simple.

Further, regarding the structure of an HDLC frame, a transmission unit in HDLC is called a frame. As shown in Figure 6, a frame consists of a flag sequence called the F pattern for synchronization, an address field, a control field, an information (data) field, and a frame check sequence (Fe
2).

The F pattern is an 8-bit sequence of 11θ1111110'', and this flag indicates the start/end of the frame.
In a sequence, it can serve both as the end of one frame and the start of the next frame.

In order to maintain the transparency of frame information, on the transmitting side, the pid pad 0 must be placed immediately after the five consecutive bits # I II.
``''Insert one hair. The receiving side receives 5 consecutive bits L
If the line immediately after L I II is II OII, it must be automatically deleted, so that the F pattern does not appear within such information.

The address field is a field for specifying a secondary station, and the control field is a field for setting control information such as command/response type and sequence number. Upper level information is set in the information field.

There are three types of control fields.

The information transfer format (I frame) is a frame for transferring information, and includes a transmission sequence number, a reception sequence number,
Consists of P/F bit. The monitoring format (S frame) is used to control reception confirmation of I frames, retransmission requests, - time suppression, etc., and includes reception sequence number, control function type,
Consists of P/F bit. The non-number format (U frame) is used to set the data link mode at the start of communication, disconnect at the end of communication, notify errors, etc.
= Consists of function type and P/F bit.

"Effects of the Invention" As described above, the present invention converts a color image signal taken by a color television camera into a digital signal, decomposes it into multiple levels of brightness signals, and transmits them to a remote location. A rough image is received in 1/1 of the time and gradually becomes a finer image.

Therefore, the visual waiting time for images can be significantly reduced. Furthermore, since it is possible to thin out and compress the contents of the video memory every other bit, even greater reductions are possible.

Furthermore, the data stored in the memory can be freely retrieved and displayed or copied at a later time. Furthermore, this is not limited to what is printed or written on a flat sheet of paper in advance, and three-dimensional objects or landscapes photographed with a television camera can also be transmitted.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a device for realizing a color image transmission method according to the present invention. Figures 2 and 3 are flowcharts, Figure 4 is VR
An explanatory diagram of AM, FIG. 5 is a front view of a television receiver, and FIG. 6 is a frame configuration diagram of an HDLC system. (1)...TV receiver, (2)...TV camera, (3)...A/D conversion circuit, (4)...digitizing circuit, (5)...first (7)... ), V-RAM, (6)
...Second V-RAM, (7)...Palette circuit,
(8)...D/A conversion circuit, (9)...floppy disk, (10)...deck, (11)...deck controller, (12)...main CPU, (1
3)...Main RAM, (14)...Serial controller, (15)...Memory switching register,
(16)...Sub CPU, (17)...Encoder, (18)...Keyboard, (19)...Modem, (20)...Communication line, (21)...Telephone ,
(22)...landmark. Applicant Fujitsu General Ltd.

Claims (3)

[Claims] (1) One screen of image data taken with a color television camera is digitally processed, separated into multiple levels of brightness for each color signal component, and stored in a video memory, and the color image stored in this video memory is A color image transmission method characterized in that signals are transmitted for each luminance. (2) The method of transmitting a color image according to claim 1, wherein the color image signal is transmitted sequentially from a high-luminance signal to a low-luminance signal. (3) A color image transmission method according to claim 1 or 2, wherein the contents of the video memory are thinned out and compressed before being transmitted.