JP2733153B2 - Image transmission device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image transmission apparatus for transmitting a video and, if necessary, a voice between two or more points separated from each other.

[0002]

2. Description of the Related Art FIG. 3 shows, for example, Mitsubishi Electric Technical Report Vol. 6
0, No. 10, 1986 is a block diagram showing a conventional image transmission apparatus, wherein 1 is a video signal input unit, 2 is an external video input terminal of the video signal input unit 1, 3
Is an input frame memory unit, 4 is an encoded frame memory unit, 5 is a subtractor for subtracting the output of each of these memory units 3 and 4, 6 is a video encoding unit for encoding the subtracted output data, and 7 is a video image. A transmission buffer unit, 8 is a video decoding unit for decoding encoded video data, 9 is an adder, 10 is an audio input unit, 11 is an external audio input terminal provided in the audio input unit 10, and 12 is an audio input unit. 13, an audio transmission buffer unit; 14, a transmission framing unit for performing multiplex framing of audio data and video data;
Is a transmission interface unit, and 16 is a line output terminal.

Next, the operation will be described. A video signal input to the video signal input unit 1 from a video input device or an external video input terminal 2 is subjected to processing such as YC separation and digital data conversion by the video signal input unit 1 and then to an input frame memory unit. 3 is stored. The video data output from the input frame memory unit 3 at a speed and data format suitable for encoding is stored in the encoded frame memory unit 4.
A difference operation is performed by the subtracter 5 on the encoded previous video data (described later) output from the above, and the result is input to the video encoding unit 6 as inter-frame difference data.

[0004] The video encoding unit 6 encodes the inter-frame difference data with high efficiency according to a predetermined algorithm, and inputs the encoded video data which has been subjected to the data amount compression to the video transmission buffer unit 7. It is input to the video decoding unit 8 for encoding. The video decoding unit 8 performs a decoding process using an algorithm opposite to the encoding, and the data output as inter-frame difference data is output from the coded frame memory unit 4. The encoded previous video data and the adder 9 are added,
The encoded current video data is stored in the encoded frame memory unit 4 for the next operation. On the other hand, the voice input unit 1
The audio signal input from the audio input device 0 or the external audio input terminal 11 is subjected to processing such as amplitude limitation in the audio signal input unit 10, and then encoded in the audio encoding unit 12, and the audio transmission buffer Stored in the unit 13.

On the other hand, the transmission framing section 14 stores the video data stored in the video transmission buffer section 7 at a predetermined transmission rate, and stores the encoded audio data stored in the audio transmission buffer section 13 as the video data. After the time adjustment, the data is input at a predetermined transmission rate. For this reason, the transmission framing unit 14 performs multiplex framing according to the transmission format, and then performs the transmission interface unit 15.
Control suitable for the transmission line is performed, and the line output terminal 1
6 to the transmission line.

As is clear from the above, the video data transmitted to the transmission line is mainly the inter-frame difference data, and for decoding on the receiving side, the encoded frame memory 4 on the transmitting side is used. If the contents do not match the same functional unit on the receiving side, correct transmission will not be performed. Therefore, the video / audio transmission apparatus sets the output data from the coded frame memory unit 4 on the transmission side, which is called an intra-frame coding mode, to certain data irrelevant to the immediately preceding data, and uses this data to generate inter-frame difference data. And a function of transmitting the operation in this mode to the receiving side in the transmission data, so that differences in the contents of the transmission / reception encoding frame memory unit 4 due to a transmission line error or the like are converged. I have.

[0007]

Since the conventional image transmission apparatus is configured as described above, when transmitting video and audio once stored, the encoded data is mainly difference data. Since it is not suitable for storage, data before encoding stored in a device such as a VTR must be input from the external video input terminal 2 and the external audio input terminal 11 using the same device. And other devices, the amount of stored data becomes enormous, and it is difficult to link the status with the incoming / outgoing state of a line.

The invention of claim 1 has been made in order to solve the above-mentioned problem, and can create, save, and transmit storage data to be transmitted without connecting to an external recording device such as a VTR. An object is to obtain an image transmission device.

According to the second aspect of the present invention, there is provided an image transmission apparatus capable of automatically executing a notification by a transmission / reproduction control unit for instructing a start of recording or reproduction of transmission data in accordance with a state of a transmission system. The purpose is to:

[0010]

An image transmitting apparatus according to the first aspect of the present invention notifies recording or reproduction, and causes a video encoding unit to start intra-frame encoding a plurality of times based on the recording notification. A transmission / reproduction control unit for returning to the inter-frame encoding and clearing the data accumulated in the video transmission buffer unit, and recording and saving the video and audio encoded data inputted after the notification. And a transmission data recording / reproducing unit for receiving the notification of the reproduction. The video data and the audio data from the transmission data recording / reproducing unit are transmitted to the transmission framing unit by a video data switch and an audio data switch. Each is switched and input.

The image transmission apparatus according to the second aspect of the present invention notifies the recording or reproduction, and after the recording notification notifies the video encoding unit to start frame encoding a plurality of times, returns to the inter-frame encoding. A transmission and recording control unit for clearing data stored in the video transmission buffer unit,
And a transmission data recording / reproducing unit for recording and storing the input video encoded data and audio encoded data after the notification, receiving the notification of the reproduction, receiving the video data from the transmission data recording / reproducing unit. And the audio data are switched and input to the transmission framing unit by the video data switch and the audio data switch, respectively, and the transmission state recognition unit recognizes the state of the transmission system. The re-control unit is controlled.

[0012]

According to the first aspect of the present invention, the transmission data recording / reproducing unit starts storing the highly-efficient coded data simultaneously with the intra-frame coding in accordance with the instruction of the transmission / recording / replay control unit. Becomes encoded data in a frame, and the encoded data can be effectively stored. As a result, V
There is no need to store and reproduce data before encoding by connecting an external device such as a TR, and the amount of stored data can be reduced by handling encoded data. Also, since the stored data is encoded data, it is possible to save the data as encrypted data using a special algorithm for encoding.

[0013] The transmission state recognizing unit according to the second aspect of the present invention causes the transmission recording / reproducing control unit to automatically output predetermined notification data according to the transmission state.

[0014]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a first embodiment of the present invention; In FIG. 1, 1 is a video signal input unit,
2 is an external video input terminal of the video signal input unit 1, 3 is an input frame memory unit, 4 is an encoded frame memory unit, 5 is a subtracter for subtracting the output of each of the memo units 3 and 4, and 6 is a subtraction output A video encoding unit for video encoding data, 7 a video transmission buffer unit, 8 a video decoding unit for decoding encoded video data, 9 an adder, 10 an audio input unit, and 11 an audio input unit 10. An external audio input terminal provided, 12 is an audio encoding unit for encoding audio input, 13 is an audio transmission buffer unit, 14 is a transmission framing unit that performs multiplex framing of audio data and video data, 15 is a transmission interface unit, 16 is a line output terminal, 20 is a transmission recording / replay control unit for selectively notifying the start of recording or reproduction of transmission data,
Reference numeral 21 denotes a transmission data recording / reproducing unit for recording and reproducing video data and audio data in response to the notification, 22, 23.
Reference numeral denotes a video data switch and an audio data switch which switch the video data and the audio data from the transmission data recording / reproduction unit in the reproduction mode and input the data to the transmission framing unit 14.

Next, the operation will be described. Since the operation at the time of normal operation is the same as that of the conventional example, the operation at the time of recording and reproducing different additional portions will be described below. First, when recording start is selected in the transmission recording / reproduction control unit 20, a notification of the recording start is sent to the video encoding unit 6, the video transmission buffer unit 7, and the transmission data recording / reproduction unit 21. Therefore, the video encoding unit 6 receives the notification, starts a new intra-frame encoding, notifies the transmission data recording / reproducing unit 21 of the start, and performs one or more intra-frame encodings. ,
Return to inter-frame coding. The video transmission buffer unit 7
Clears the data stored before the notification. Further, the transmission data recording / reproducing unit 21 records and stores the input video encoded data and audio encoded data after the above two notices are given.

On the other hand, when the start of reproduction is selected in the transmission / reproduction control section 20, the video data switch 22 and the audio data switch 23 are switched to the output side of the transmission data recording / reproduction section 21, and the transmission data recording / reproduction section 21 By sequentially outputting the stored data from the first recorded intra-frame encoded data, transmission framing and interface processing are performed and transmitted.

FIG. 2 shows an embodiment of the present invention. In this embodiment, the invention of claim 1 controls the transmission data recording / reproducing unit 21 by notifying the start of intra-frame encoding of the video encoding unit 6 and the transmission recording / replay control unit 2 by human operation.
The transmission status recognizing unit 30 is connected to the transmission recording / reproducing control unit 20, and the transmission recording / reproducing control unit 20 is automatically controlled by the transmission status recognizing unit 30. It is like that. In other words, the transmission / reproduction control unit 20 is controlled in accordance with the state of the transmission system, for example, the operation mode determined by the incoming call, line synchronization, or in-channel data, and the control output is used as notification data to control the transmission data recording / reproduction unit 21. Enable control.

[0018]

As described above, according to the first aspect of the present invention, the recording or reproduction is notified, and after the video encoding unit is started a plurality of times of intra-frame encoding by the recording notification, the A transmission recording / replay control unit that clears data stored in the video transmission buffer unit, while returning to encoding,
And a transmission data recording / reproducing unit for recording and storing the input video encoded data and audio encoded data after the notification, receiving the notification of the reproduction, receiving the video data from the transmission data recording / reproducing unit. And the audio data is switched and input to the transmission framing unit by the video data switch and the audio data switch, respectively, so that the same system as that in normal transmission can be used without using other external devices such as a VTR. With the configuration, digital data with a small amount of recorded data can be effectively recorded, and furthermore, this can be reproduced and transmitted. In addition, the data after encoding is encoded by a special algorithm in order to record and save the data. For data, there is an effect that a data that can keep data confidential can be obtained.

According to the second aspect of the present invention, recording or reproduction is notified, and after the recording is notified, the video encoding unit starts intra-frame encoding a plurality of times, and then returns to inter-frame encoding. A transmission recording / reproducing control unit for clearing data stored in the video transmission buffer unit, and a transmission data recording / reproducing unit for recording and storing video encoded data and audio encoded data that are input after the notification, In response to the notification of the reproduction, the video data and the audio data from the transmission data recording / reproduction unit are switched and input to the transmission framing unit by the video data switch and the audio data switch, respectively. A state recognition unit is provided to control the transmission / reception control unit in accordance with the recognition result of the transmission system. You can control the transmission data reproducing unit by the notification data according to the determination or the like of the operation mode by there is an effect to be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an image transmission apparatus according to an embodiment of the present invention.

FIG. 2 is a block diagram showing an image transmission apparatus according to an embodiment of the present invention.

FIG. 3 is a block diagram showing a conventional image transmission device.

[Explanation of symbols]

 Reference Signs List 3 input frame memory unit 4 encoded frame memory unit 5 subtracter 6 video encoding unit 7 video transmission buffer unit 8 video decoding unit 9 adder 12 audio encoding unit 13 audio transmission buffer unit 14 transmission framing unit 20 Control unit 21 Transmission data recording / reproducing unit 22 Video data switching unit 23 Audio data switching unit 30 Transmission state recognition unit

Claims (2)

(57) [Claims] 1. An input frame memory unit in which a video signal is stored, and a subtractor for calculating a difference between video data from the input frame memory unit and encoded previous video data to obtain inter-frame difference data. A video encoding unit that performs high-efficiency encoding of the inter-frame difference data to output video encoded data, a video decoding unit that decodes the encoded video data to generate inter-frame difference data, An adder that adds the inter-frame difference data from the encoding unit to the encoded previous video data and outputs encoded current video data, and performs the encoding based on the addition output data of the adder. A pre-processed video data is generated, and an encoded frame memory to be input to the subtractor, a video transmission buffer for storing video encoded data from the video encoding unit, and an audio signal are encoded. An audio encoding unit, an audio transmission buffer unit for storing the encoded audio data, and the video encoded data from the video transmission buffer unit and the audio transmission buffer unit time-adjusted for the video encoded data. In a video transmission apparatus having a transmission framing unit for performing multiplex framing of audio coded data and outputting the same, a recording or reproduction is notified, and the video coding unit is notified of the recording by a plurality of times of intra-frame coding. After the start, the transmission and replay control unit for returning to the inter-frame encoding and clearing the data stored in the video transmission buffer unit, and the video encoded data and the audio code input after the notification. A transmission data recording / reproducing unit for recording and storing the coded data, and receiving the notification of the reproduction, and Audio data and image transmission apparatus, characterized in that a video data selector and the audio data switching unit for input switching each to the transmission framing unit. 2. An input frame memory unit in which a video signal is stored, and a subtractor for calculating a difference between video data from the input frame memory unit and encoded previous video data to obtain inter-frame difference data. A video encoding unit that performs high-efficiency encoding of the inter-frame difference data to output video encoded data, a video decoding unit that decodes the encoded video data to generate inter-frame difference data, An adder that adds the inter-frame difference data from the encoding unit to the encoded previous video data and outputs encoded current video data, and performs the encoding based on the addition output data of the adder. A pre-processed video data is generated, and an encoded frame memory to be input to the subtractor, a video transmission buffer for storing video encoded data from the video encoding unit, and an audio signal are encoded. An audio encoding unit, an audio transmission buffer unit for storing the encoded audio data, and the video encoded data from the video transmission buffer unit and the audio transmission buffer unit time-adjusted for the video encoded data. In a video transmission apparatus having a transmission framing unit for performing multiplex framing of audio coded data and outputting the same, a recording or reproduction is notified, and the video coding unit is notified of the recording by a plurality of times of intra-frame coding. After the start, the transmission and replay control unit for returning to the inter-frame encoding and clearing the data stored in the video transmission buffer unit, and the video encoded data and the audio code input after the notification. A transmission data recording / reproducing unit for recording and storing coded data, and receiving the notification of the reproduction, and A video data switch and an audio data switch for switching and inputting the audio data to the transmission framing unit, and a transmission state recognition unit for recognizing the state of the transmission system and controlling the transmission / reproduction control unit in accordance with the recognition result. And an image transmission device.