JPH077580A - Still image transmission device - Google Patents

Abstract

(57) [Abstract] [Purpose] In the encoding / decoding unit of the still image transmission device, all the data handled in the terminal is processed by the standard table to simplify the control of the encoding unit and to transmit the data. And improve the efficiency of storage processing. [Structure] The image processing unit 4 has three types of tables for encoding / decoding, a reception image transmission / reception table 22, a captured image transmission table 23, and a storage / reproduction table 24. A table detection / comparison circuit 21 is provided. When each image data is transmitted, each code table is added and output.
The code table detection / comparison circuit 21 detects the code table, transmits the added code table as it is when the data is different, and deletes the added code table and transmits when the data is the same.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a still image transmitting apparatus for transmitting and receiving image information using a communication line, and more specifically, a coding / decoding section of the image transmitting apparatus handles it within its own terminal. The present invention relates to a still image transmission apparatus in which control of an encoding unit is simplified and processing of transmission and storage is efficiently performed by processing all data by a standard table.

[0002]

2. Description of the Related Art DCT (Discrete Cosine Transform) is one of the methods for compressing and encoding color still image data.
There is a method. In this method, in order to transmit data efficiently, a difference between different components depending on the characteristics of a still image is tabulated as a coefficient to reduce the amount of each transmitted data. For example, in the case of a system that transmits and receives natural images, a natural image code table is prepared as a standard table on each of the transmitting side and the receiving side, so that encoding / decoding can be performed without transmitting the code table data itself. Since the amount of data to be transmitted can be reduced and the time required for transmission and reception can be shortened, efficient transmission is possible.

However, the code table generally has a standard table common to the transmitting side and the receiving side, and if it is added on the receiving side of the image data, it is the added table and the code table is added. If not, the standard table or the table transmitted immediately before the standard table is used for decoding. In the example of FIG. 6, assuming that T0 is the standard table, the code table data is not added to the image data D0 transmitted first, so decoding is performed using the standard table T0 and the code table T1 is added. The image data D1 is decoded by the code table T1, and the image data D2 transmitted next is not added with the code table data. Therefore, the code table T transmitted immediately before is decoded.
1. Similarly, the image data D2 is decoded as the code table T1, D3 as T1, D4 as T2, and D5 as T2.

In a system using such a compression / encoding system, when the received image data is recorded in the storage device and the reproduced image data is transmitted to the partner terminal, a still image transmission device is constructed. The encoding / decoding unit requires two types of tables for transmission and reception. The reception table is necessary for holding the table data added to the reception image data as shown in FIG. 6, and the transmission table is necessary for encoding / decoding the accumulated image or encoding the captured image.

When the image data is transmitted by the system having such a configuration, the image data and the table data must not be inconsistent with the decoding unit of the other party. Therefore, when adding the table data in the encoding / decoding unit. Requires complex management. For example, table data need not be added to the captured image encoded by the standard table immediately after the line connection, but table data need to be added to the accumulated image data having table data different from the standard. In addition, when the captured image is encoded after transmitting the accumulated image data having the table data different from the standard, it is necessary to reload the standard table data in the table on the transmitting side and add the table data for transmission. Conventionally, in order to easily solve the problem without complicated table addition management control of the encoding / decoding unit, the only method is to add a table to all transmission data.

[0006]

As described above, in the conventional still image transmission apparatus, since the table data is added to all the transmission data, the transmission data amount is large, and the compression / encoding method is originally efficient. There was a drawback that transmission was not possible. In addition, the code table data may be added to the transmission data, and the code table data must be added to the accumulated image data without fail. Therefore, the disadvantage is that the transmission time is long and the number of accumulated data is small. was there.

The present invention has been made in view of the above circumstances, and provides a still image transmission apparatus having a code table detection / comparison function and a standard coding table with a simple coding processing function. Has an aim.

[0008]

In order to achieve the above object, the present invention provides (1) means for taking in still image data obtained by digitally converting a video signal into a memory, and a transmission / reception image. A transmission / reception memory for displaying / storing, a coding / decoding device for compressing / decompressing image data during transmission / reception processing, and a storage device for recording / reproducing / storing received or captured image data. In a still image transmission device that is provided with the transmission / reception of image information via a communication line, the transmission image data output stage has a code table detection / comparison circuit, and the encoding / decoding device uses a new code table reception. Two types of code tables for receiving and transmitting the received image data and for transmitting and receiving the stored and reproduced image data, which are updated at any time, and a captured image data transmitting code table that always has a standard value are provided. When transmitting each image data, each code table is added and output, and the code table detection / comparison circuit detects the code table and compares it with the table of the image data transmitted immediately before that. If the data is different, the additional code table is transmitted as it is, and if the data is the same, the additional code table is deleted and transmitted, or (2) the video signal is digitally transmitted. A means for loading the still image data obtained by the conversion into a memory, and transmitting / receiving
A transmission / reception memory for displaying / accumulating a reception image, a coding / decoding device for compressing / decompressing image data at the time of transmission / reception processing, and recording / playback / storing of received or captured image data. In the still image transmission device, comprising: a storage device for transmitting and receiving image information via a communication line, the encoding / decoding device includes a code table for receiving image data that is updated at any time by receiving a new code table, And a code table for transmitting captured image data, transmitting / receiving stored image data, and receiving image data, which always have standard values, and a code table for transmitting captured image data, transmitting / receiving stored image data, and receiving image data. It is characterized in that it is provided with a coding / decoding means for always coding / decoding with a standard table.

[0009]

According to the present invention, it is not necessary for the encoding / decoding section to judge whether the table should be added or not, and the circuit can be simplified. Further, by having the code table for transmitting / receiving the stored / reproduced image data and the code table for transmitting the captured image data, the transmitting side when encoding the captured image after transmitting the accumulated image data having table data different from the standard It is not necessary to reload the standard table data to the table, and the processing time is reduced, and the code table detection / comparison circuit compares with the table of the image data transmitted immediately before and adds / deletes the code table. Since there is provided a means for transmitting the data, the data can be efficiently transmitted, and the operability of the apparatus is significantly improved.

Further, since the transmission data does not need to include the encoding table data, the amount of transmission data is small, the transmission time is shortened, and the accumulated data need not include the encoding table data. The number of absolute image data stored in the storage device increases, and there is no need to perform complicated table addition management in the image encoding / decoding unit, which has the effect of significantly improving the operability of the device.

[0011]

Embodiments will be described below with reference to the drawings. FIG. 1 is a block diagram for explaining an embodiment of a still image transmission apparatus according to the present invention, in which 1 is a communication circuit and 2 is a communication circuit.
Is a communication interface unit, 3 is an image transmission / reception buffer memory, 4 is an image processing unit, 5 is a reception memory, 6 is a video output unit, 7 is a monitor, 8 is a camera, 9 is a video input unit, 10 is a transmission memory, and 11 is a memory. System control unit, 12 is a storage device,
Reference numeral 13 is an operation unit, 14 is a voice processing unit, and 15 is a handset.

Audio information / still image information / call control information input / output from the still image transmission apparatus of the present invention is connected to the communication line 1 via the communication interface section 2 and transmitted. In the communication interface unit 2, two information channels and one control signal channel are demultiplexed. First, the image processing unit 4 performs image compression / decompression / encoding / decoding during transmission / reception when the reception memory 5 and the transmission memory 10 are connected. The image processing unit 4 operates under the control of the system control unit 11 and performs data compression / decompression / encoding / decoding processing when transmitting / receiving still image data. Still image information is input from the communication line 1, separated by the communication interface unit 2, and then input to the image transmission / reception buffer memory 3, control information and the like are extracted, and only image information is extracted, and the image processing unit 4 The decoding process and the decompression process of the compressed and transmitted information are performed and temporarily stored in the reception memory 5. The image data stored in the reception memory 5 is D / A converted into an analog video signal by the video output unit 6 so as to be output to the monitor 7, and the image is displayed on the monitor 7 adjusted to an appropriate level. .

When transmitting image information, the image data (captured image data) converted into an analog image signal by the camera 8 is adjusted to an appropriate level by the image input unit 9 and converted into digital data by A / D conversion. The converted data is temporarily stored in the image transmission memory 10 and is output from the video output unit 6 to the monitor 7. Further, the image data stored in the transmission memory 10 is subjected to image compression processing and encoding processing in the image processing unit 4 to form a digital image information signal, which is necessary for transmission in the image transmission / reception buffer memory 3. Control information and the like are added, supplied as a signal of an information channel to the communication interface 2, multiplexed, and transmitted to the other terminal through the communication line 1.
Reference numeral 12 denotes a storage device for recording / reproducing / storing the received or captured image data. The image data in the reception memory 5 or the transmission memory 10 is compressed / encoded via the image processing unit 4 and stored in the storage device 12. Records are kept.

The operation unit 13 is for inputting a dial number when making a call, and the operation signal is supplied to the system control unit 11 for processing. In addition, a handset 15 is connected to the voice processing unit 14, and during a call, an analog voice signal output from the microphone unit of the handset 15 is input to the voice processing unit 14 and is subjected to A / D conversion processing and the like and digitally processed. Voice information signal is formed, is supplied to the communication interface section 2 as an information channel signal, is multiplexed, and is transmitted to the other party through the communication line 1. Also, the voice signal from the other party's terminal is input to the communication interface unit 2 via the communication line 1, separated from the signal of the information channel into digital voice data, processed by D / A conversion and the like, and converted into analog voice. A signal is formed and voice is output from the speaker unit of the handset 15.

FIG. 2 is a block diagram for explaining the code table detection / comparison circuit of the still image transmission apparatus according to the present invention. In the figure, 21 is a table detection / comparison circuit, 22 is a TR (received image table), 23 is a TO (captured image table), 24 is a TS (stored and reproduced image table),
Other parts that have the same functions as those in FIG. 1 are designated by the same reference numerals.

The image processing unit 4 has three types of tables, that is, a received image transmission / reception table 22, a captured image transmission table 23, and a storage / reproduction table 24 as encoding / decoding tables. A table detection / comparison circuit 21 is provided. As shown in FIG. 6, the still image data transmitted from the partner terminal is transmitted with both the code table not added and the code table added. It is indispensable to have the received image table 22 so as to be able to cope with the table change (the contents of the table should not be changed by the storage reproduction).

The received image data a is the received image table 2
The image signal of Y, CB, and CR is decoded by 2 and stored in the receiving memory 5. In addition, the transmission memory 10
Stored either in the captured image data captured by the camera 8 or the accumulated image data in which the image data recorded in the storage device 12 is reproduced and displayed.
In the case of captured image data, when the content of the code table is other than the standard value due to the reproduced image data, it is necessary to reset the standard table value, and processing time is required, so the captured image data transmission encoding table 23 is provided. In the case of stored image data, the table contents may differ each time it is played back, and thus the stored image data table 24 is provided.

When these image data are transmitted to the partner terminal, the contents of each table may be different. Therefore, depending on the type and order of the image to be transmitted, a table may or may not be added, and complicated management and control may be required. Will be required. Therefore, in this system, table data is added to all the image data output from the image processing unit 4 without complicated management control and output (b, c,
e), the table detection / comparison circuit 21 compares each transmission data with the table of the immediately preceding transmission to realize efficient transmission.

The received image, the captured image, and the accumulated image are coded by each table as image data with a table and input to the table detection / comparison circuit 21. Here, the image data includes the image data start code 31 and the image data end code 3 as shown in FIG.
Enclosed by 6 and having a table data header code 32 at the beginning of the code table data 33 and an image data header code 34 at the beginning of the image data 35, the code table data including the table data header code 32 33 can be omitted.

FIG. 4 is a flow chart for explaining the operation of the table detection / comparison circuit according to the present invention.
Hereinafter, each step will be described in order. First, step1
If there is no input for determining whether the image data has been input by detecting the image data start code 31 in step 1, repeat step 1
If is detected, the process proceeds to step 2 and the next data is verified. In step 2, the table data header code 32 is detected, and if different, go to step 7. If the table data header code 32 is detected, it is compared with the table data of the image data transmitted immediately before in step 3, and it matches in step 4. If so, the table data is extracted and deleted (step 5). If they do not match, the table data is added and output, and the table data is temporarily stored for comparison with the next data. The image data end code 36 is detected in step 7, and if different, step
The next data is searched in 2 and the image data end code 36
In the case of detection, the processing is ended and the next still image data input is awaited. Through the above processing, the table detection / comparison circuit 21
The output data of is in an efficient and optimal state.

FIG. 5 is a block diagram showing another embodiment of the still image transmission apparatus according to the present invention, and is a block diagram for explaining the operation of the simple coding process by the standard coding table.
In the figure, 51 is a received image table, 52 is a standard table, and other parts having the same operations as in FIG. The image processing unit 4 has two types of tables, a reception image transmission / reception table 51 and a captured image transmission / storage / reproduction table 52 as encoding / decoding tables.

As shown in FIG. 6, the still image data transmitted from the partner terminal is transmitted with both the code table not added and the code table added. It is indispensable to have the received image table 51 so as to be able to cope with table changes other than the above, and the received image data A is decoded by the received image table 51 into Y, CB, and CR image signals, and the received memory 5 Stored in. Further, the transmission memory 10 stores either captured image data captured by the camera 8 or accumulated image data obtained by reproducing and displaying the image data recorded in the storage device 12.

Here, in this system, in order to perform complicated management and transmission in the image processing unit 4 and to reduce the data amount of the stored image,
At the time of transmission or storage, regardless of the received image, captured image, or stored image, the encoding / decoding processing is performed using the standard table. Therefore, it is not necessary to add the code table data to the image data in the route of B, C, D,
Since the data amount of the image data itself is reduced, the transmission time is shortened and the number of absolute image data stored in the storage device is increased.

[0024]

As is apparent from the above description, the present invention has the following effects. (1) Effect corresponding to claim 1: It is not necessary for the encoding / decoding unit to determine whether to add a table, and the circuit can be simplified. Further, by having the code table for transmitting / receiving the stored / reproduced image data and the code table for transmitting the captured image data, it is possible to transmit the accumulated image data having table data different from the standard after transmitting the captured image. There is no need to reload the standard table data into the side table, and the processing time is reduced. Further, the code table detection / comparison circuit includes means for comparing with the table of the image data transmitted immediately before, and adding / deleting the code table to transmit, so that efficient data transmission can be performed. (2) Effect corresponding to claim 2: Since transmission data and accumulated data do not need to include encoding table data,
Since the amount of data to be transmitted is small, the transmission time is shortened, and the number of absolute image data to be stored in the storage device is increased, the waiting time during image transmission / reception and storage is reduced, and the operability of the device is significantly improved. It has the effect of improving.

[Brief description of drawings]

FIG. 1 is a configuration diagram for explaining an embodiment of a still image transmission device according to the present invention.

FIG. 2 is a block diagram for explaining a code table detection / comparison circuit of the still image transmission apparatus according to the present invention.

FIG. 3 is a diagram showing an image data format in the present invention.

FIG. 4 is a flowchart for explaining the operation of the table detection / comparison circuit in FIG.

FIG. 5 is a diagram showing another embodiment of the still image transmission apparatus according to the present invention.

FIG. 6 is a diagram showing an example of conventional image data transmission.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Communication circuit, 2 ... Communication interface part, 3 ... Image transmission / reception buffer memory, 4 ... Image processing part, 5 ... Reception memory, 6 ... Video output part, 7 ... Monitor, 8 ... Camera, 9 ... Video input part, 10 ... transmission memory, 11 ... system control unit,
12 ... Storage device, 13 ... Operation unit, 14 ... Voice processing unit, 1
5 ... Handset.

Claims (2)

[Claims] 1. A means for fetching still image data obtained by digitally converting a video signal into a memory, a transmission / reception memory for displaying and accumulating transmission / reception images, and image data during transmission / reception processing. In a still image transmission device that includes an encoding / decoding device for compressing / decompressing an image and a storage device for recording / reproducing / storing received or captured image data, and that transmits / receives image information via a communication line. , The transmission image data output stage has a code table detection / comparison circuit, and the encoding / decoding device is provided with two types of transmission / reception image data transmission / reception and storage reproduction image data transmission / reception that are updated at any time by receiving a new code table. It has a code table and a code table for transmitting captured image data that always has a standard value. When transmitting each image data, each code is sent. No. table is added and output, and the code table detection / comparison circuit detects the code table and compares it with the table of the image data transmitted immediately before, and if the data is different, the added code table is unchanged. A still image transmitting apparatus comprising: a transmitting unit that transmits and deletes an added code table when transmitting the same data. 2. A means for fetching still image data obtained by digitally converting a video signal into a memory, a transmission / reception memory for displaying / storing an image for transmission / reception, and image data during transmission / reception processing. In a still image transmission device that includes an encoding / decoding device for compressing / decompressing an image and a storage device for recording / reproducing / storing received or captured image data, and that transmits / receives image information via a communication line. The encoding / decoding device has a code table for receiving image data reception, which is updated at any time by receiving a new code table, and a code for transmitting captured image data and storing / reproducing image data transmission / reception and receiving image data transmission which always has a standard value. And a code table for transmitting the captured image data, transmitting / receiving the stored image data, and transmitting the received image data. A still image transmission apparatus, characterized in that it is provided with a coding / decoding means for coding / decoding with a standard table.