JPH08321828A - Encoding signal transmission device - Google Patents

Abstract

PURPOSE: To decode the encoding signal of a low bit rate to output it through the use of a decoding signal generation means corresponding to a conventional and specified bit rate by providing a means for converting the bit rate of the encoding signal into a bit rate higher than the rate. CONSTITUTION: A bit rate conversion information generation part 5 inputs information on the rate change of the bit rate of the encoding signal from outside and outputs it to a control part 2 as bit rate conversion information. A frame generation part 6 updates bit rate information included in extracted encoding information in accordance with the output of the control part 2 and sequentially transmits a synchronous pattern, encoding information and encoding data at the updated bit rate by controlling transmission timing. Then, a zero signal is transmitted as correction data until it reaches the transmission time of one frame, which is previously decided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coded signal transmission apparatus for coding information such as a voice signal and transmitting it efficiently.

[0002]

2. Description of the Related Art In recent years, by encoding information,
Technologies for efficiently storing and transmitting the information have been developed. When transmitting an audio signal, for example, I
SO standard MPEG (Moving Pictures Experts Group):
Signals are encoded using encoding methods such as the Video Expert Group). There is also an apparatus that stores the encoded signal in an information storage medium and transmits the information. DCC (Digital
(Compact Cassette: Digital Compact Cassette)
The encoding method used in the PASC (Precision
This is called Adaptive Subband Coding) and is based on ISO / IEC11172-3 in the above-mentioned MPEG standard proposal.

A description of the MPEG standard is omitted here, but in the PASC system, the bit rate is limited to 384 kbps, and the sampling frequency is 48 kHz, 44.1 kHz, 32 kH.
One of z is used.

An example of a coded signal transmission device using the above-described coding method will be described below.

FIG. 9 is a block diagram showing the structure of a conventional coded signal transmission device. Reference numeral 21 is a coded signal generation means, 22 is a modulation means, 23 is a demodulation means, and 24 is a decoded signal generation means. The encoded signal generation means 21 receives an audio signal, encodes the signal in frame units of a fixed length, and outputs the encoded signal at a predetermined specific bit rate. Modulating means 22
Is an input of the encoded signal, and a wireless or wired transmission path 25
The modulated signal is output using a modulation method suitable for.

The demodulation means 23 receives the modulated signal,
It demodulates to a constant frame length coded signal and outputs it. The decoded signal generation means 24 decodes a constant frame length coded signal transmitted at a predetermined specific bit rate into a speech signal and outputs it.

[0007]

However, in the above-mentioned conventional coded signal transmission apparatus, the coded signal generation means generates and transmits a coded signal of a low bit rate capable of more efficient information compression. In this case, the conventional decoded signal generating means has a problem that a complicated synchronization detecting circuit corresponding to a plurality of bit rates is required.

Further, in the above conventional apparatus, the coded signal generating means generates a variable frame length coded signal having a variable frame length, which enables more efficient information compression and transmission than the constant frame length coded signal. In the case of transmitting by using the conventional method, there has been a problem that the conventional means for detecting the synchronizing signal of the decoded signal generating means needs to be a complicated circuit in consideration of the variable frame length.

Further, the conventional device has a problem that it is necessary to generate a frame signal having a synchronization signal for each information to be transmitted, and additional information cannot be transmitted in the same frame.

An object of the present invention is to solve the above-mentioned conventional problems, and to cope with a specific bit rate of the related art by providing a means for converting the bit rate of the encoded signal into a higher bit rate. It is a first object of the present invention to provide a decoded signal transmission device capable of decoding and outputting a low bit rate encoded signal by using the decoded signal generating means.

Further, by providing the means for expanding the frame length, it is possible to decode and output the variable frame length coded signal by utilizing the conventional decoded signal generating means corresponding to the constant frame length coded signal. A second object is to provide a decoded signal transmission device that can be used.

Further, by providing means for superimposing the additional information on the correction portion at the time of expanding the frame length of the encoded signal, it is not necessary to generate a frame signal having a synchronization signal each time the additional information is transmitted. A third object is to provide a signal transmission device.

[0013]

In order to achieve the first object, a coded signal transmission apparatus according to the present invention according to claim 1 is a code for generating a first coded signal composed in frame units. An encoded signal generation unit, a control unit that detects a synchronization pattern from the first encoded signal, and generates a control signal at a timing that corresponds to the detected synchronization pattern, and the first control unit that outputs the control signal. A coded information extraction unit that extracts coded information from a coded signal; a coded data extraction unit that extracts coded data from the first coded signal according to the output of the control unit; A bit rate conversion information generation unit that generates bit rate conversion information indicating a rate equal to or higher than the bit rate of the encoded signal and outputs the bit rate conversion information to the control unit;
A frame generation unit that combines the output of the encoded information extraction unit and the output of the encoded data extraction unit, updates the encoded information according to the output of the control unit, and generates a second encoded signal. It is characterized by having and.

In order to achieve the second object, a second aspect is provided.
The coded signal transmission device according to the present invention described in claim 1 is the coded signal transmission device according to claim 1, wherein the first
A frame length information extraction unit for extracting frame length information from the encoded signal of the above, and in the frame generation unit, the output of the encoded information extraction unit and the output of the encoded data extraction unit are combined, and the output of the control unit and the frame The encoding information is updated according to the output of the length information extracting unit to generate the second encoding information.

In order to achieve the third object, claim 3
The coded signal transmission device according to the present invention described in the above is the coded signal transmission device according to claim 2, further comprising an additional information input unit for inputting additional information for the first coded signal, and the frame generation unit, The output of the encoded information extraction unit and the output of the encoded data extraction unit are combined, and the encoded information is updated according to the output of the control unit and the output of the frame length information extraction unit,
It is characterized in that the second coded information is generated and the additional information is superposed on a correction portion generated when the first coded signal is converted into the second coded signal.

[0016]

In the coded signal transmission device according to the present invention, the bit rate of the generated coded signal is converted to a higher bit rate and the signal to which correction data is added so as to maintain the frame length is transmitted. You can

In the coded signal transmission device according to the second aspect,
It is possible to add the correction data to the frame length of the generated encoded signal and transmit the expanded signal.

In the coded signal transmission device according to claim 3,
When adding the correction data to the frame length of the generated encoded signal to expand the frame, the additional information can be superimposed on the correction portion before transmission.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of the first embodiment of the present invention, in which 1 is an encoded signal generator, 2 is a controller,
3 is a coded information extraction unit, 4 is a coded data extraction unit, 5 is a bit rate conversion information generation unit, and 6 is a frame generation unit.

In the first embodiment, the coded signal generator 1
Encodes the input audio signal in a predetermined constant frame unit and transmits the constant frame length encoded signal at a specific bit rate, for example, 96 kbps. FIG. 2 is an explanatory diagram showing an example of a frame configuration of a coded signal. The coded signal includes a synchronization pattern used for synchronization detection, coding information that is information for coding the signal, and a voice signal. One frame is composed of the encoded data that has been encoded.

The control unit 2 detects the sync pattern from the coded signal, detects the coded information and the coded data at a predetermined position with respect to the sync pattern, and uses those detected signals as control signals. Output. Encoding information extraction unit 3
Extracts the coded information from the coded signal at the timing of the coded information detection signal of the control unit 2. The encoded data extraction unit 4 extracts encoded data from the encoded signal at the timing of the encoded data detection signal of the control unit 2. The bit rate conversion information generating unit 5 inputs from outside the bit rate of the encoded signal, for example, changing the bit rate from 96 kbps to 384 kbps, and the bit rate conversion information is output as the control unit 2 as bit rate conversion information. Output to.

The frame generator 6 updates the bit rate information contained in the extracted coded information in accordance with the output of the controller 2, and then controls the transmission timing to control the synchronization pattern and the coded information. And the encoded data are sequentially transmitted at the updated bit rate, and thereafter, a zero signal is transmitted as the correction data until the predetermined one-frame transmission time is reached.

FIG. 3 is an explanatory diagram showing a frame structure in which the bit rate of the coded signal of FIG. 2 is converted to a higher value and correction data is added. This frame is a synchronization pattern, coding information, coded data and correction data. Composed of and.

As described above, according to the first embodiment, the bit rate of the first coded signal formed in a fixed frame unit is converted to a high value, and the sending time of one frame is kept equal to that before conversion. Thus, the second constant frame length coded signal in which the correction data is added to the coded signal can be transmitted.

FIG. 4 is a block diagram showing the configuration of the second embodiment of the present invention. Hereafter, the members corresponding to the components of the first embodiment which have already been described are designated by the same reference numerals and detailed description thereof will be omitted. To do. The second embodiment differs from the first embodiment in that the frame length information extraction unit 10 is provided.

In the second embodiment, the coded signal generator 1
Encodes the input audio signal in variable frame units and outputs it. FIG. 5 is an explanatory diagram showing an example of a frame structure of a coded signal of a variable frame length. The coded variable frame length signal is a synchronization pattern used for synchronization detection, and coding that is information for coding the signal. One frame is composed of information, frame length information indicating how much the frame length of a coded signal is extended, and coded data obtained by coding voice data.

The control unit 2 detects a sync pattern from the coded signal, detects coded information and coded data at a predetermined position with respect to the sync pattern, and uses those detection signals as control signals. Output. Encoding information extraction unit 3
Extracts the coded information from the coded signal at the timing of the coded information detection signal of the control unit 2. The encoded data extraction unit 4 extracts encoded data from the encoded signal at the timing of the encoded data detection signal of the control unit 2. The bit rate conversion information generation unit 5 outputs the same rate information as the bit rate of the encoded signal to the control unit 2.

The frame length information extraction unit 10 extracts frame length information from the encoded signal at the timing of the frame length information detection signal of the control unit 2. How much this frame length information extends the frame length of the encoded signal, for example,
Indicates information such as expansion to 144 bytes to 288 bytes. The frame generation unit 6 updates the information of the frame length included in the encoded information based on the extracted frame length information, and then controls the transmission timing of the encoded signal by the control signal to generate the synchronization pattern. The encoded information, the frame length information, and the encoded data are sequentially transmitted, and a zero signal is transmitted as correction data until the length of one frame reaches the length designated by the frame length information.

FIG. 6 is an explanatory diagram of a frame structure in which correction data is added to the encoded signal of FIG. 5 to expand the frame. This frame is composed of a synchronization pattern, coding information, frame length information, coded data, and correction data.

As described above, according to the second embodiment, the second encoding is performed by adding the correction data to the frame length of the first encoded signal formed in variable frame units to extend the frame length. It can be converted into a signal and transmitted.

FIG. 7 is a block diagram showing the construction of the third embodiment of the present invention. In the following, the same reference numerals are given to the members corresponding to the constituent members of the first embodiment and the second embodiment already explained. And detailed description is omitted. The third embodiment differs from the second embodiment in that the additional information input section 11 is provided.

In the third embodiment, the coded signal generator 1
Encodes the input audio signal in variable frame units and outputs it. The control unit 2 detects the sync pattern from the coded signal, detects the coded information, the frame length information, and the coded data at a predetermined position with respect to the sync pattern, and outputs the detected signals as a control signal. Output as.
The encoded information extraction unit 3 extracts encoded information from the encoded signal at the timing of the encoded information detection signal of the control unit 2. The encoded data extraction unit 4 uses the encoded signal to control the control unit 2.
The encoded data is extracted according to the timing of the encoded data detection signal of. The bit rate conversion information generation unit 5 outputs the same rate information as the bit rate of the encoded signal to the control unit 2.

The frame length information extraction unit 10 extracts frame length information from the encoded signal at the timing of the encoded information detection signal of the control unit 2. This frame length information indicates how much the frame length of the encoded signal should be expanded. The additional information input unit 11 can externally provide additional information such as control information for controlling the receiving device of the encoded signal to be transmitted. The frame generation unit 6 updates the information of the frame length included in the encoded information based on the extracted frame length information, and then controls the transmission timing of the encoded signal by the control signal while When the correction data is added until the length of one frame reaches the length specified by the frame length information, the additional information is superimposed on the correction portion. The encoded signal is transmitted.

FIG. 8 is an explanatory diagram of a frame structure in which additional information is added to the coded signal of FIG. 5, and this frame is composed of a synchronization pattern, coding information, frame length information, coded data and additional information. To be done.

As described above, according to the third embodiment, the additional information can be superimposed and output when the encoded information is expanded.

[0037]

As described above, according to the configuration of the first aspect of the coded signal transmission apparatus of the present invention, since the bit rate of the coded signal can be converted to be high, the DCC can be converted. It is also possible to decode a low bit rate coded signal having a higher coding efficiency by using a decoded signal generation means corresponding to a specific coded bit rate such as the PASC coding LSI used in 1.

According to the structure of claim 2, since the frame length of the coded signal can be expanded, the decoded signal generating means for decoding only the coded signal of the constant frame length is used to extract the coded signal of the constant frame length. Also, it is possible to decode a variable frame length coded signal with high compression efficiency. Similarly, the variable frame length coded signal efficiently compressed and stored in the storage medium can be decoded by using the conventional decoded signal generating means.

According to the third aspect of the present invention, the additional information is superimposed and transmitted on the correction portion when the frame length is expanded, so that independent information sharing the synchronization detection can be transmitted.
The additional information can be extracted by a simple additional circuit while decoding the coded signal using the conventional decoded signal generation means.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a coded signal transmission device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of a frame structure of a coded signal.

FIG. 3 is an explanatory diagram of a frame configuration of an encoded signal obtained by converting a bit rate of the encoded signal of FIG. 2 to a higher rate and adding correction data.

FIG. 4 is a block diagram showing a configuration of a coded signal transmission device according to a second exemplary embodiment of the present invention.

FIG. 5 is an explanatory diagram of a frame configuration of an encoded signal having frame length information.

6 is an explanatory diagram of a frame structure in a coded signal in which correction data is added to the coded signal in FIG. 5 and a frame length is expanded.

FIG. 7 is a block diagram showing a configuration of a coded signal transmission device according to a third exemplary embodiment of the present invention.

8 is an explanatory diagram of a frame configuration in a coded signal in which additional information is added to the coded signal of FIG.

FIG. 9 is a block diagram showing a configuration of a conventional coded signal transmission device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Encoded signal generation part, 2 ... Control part, 3 ... Encoding information extraction part, 4 ... Encoded data extraction part, 5 ... Bit rate conversion information generation part, 6 ... Frame generation part, 10 ... Frame length information extraction Section, 11 ... Additional information input section.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location H04N 5/928 H04N 5/92 E 7/24 7/13 Z

Claims (3)

[Claims] 1. A coded signal generation unit for generating a first coded signal configured in frame units, a sync pattern is detected from the first coded signal, and at a timing according to the detected sync pattern. A control unit that generates a control signal; a coding information extraction unit that extracts coding information from the first coded signal in response to an output of the control unit; A coded data extraction unit that extracts coded data from a coded signal, and bit rate conversion information that generates bit rate conversion information indicating a rate equal to or higher than a bit rate of the first coded signal and outputs the bit rate conversion information to the control unit. A generation unit, an output of the encoded information extraction unit and an output of the encoded data extraction unit are combined, the encoding information is updated according to the output of the control unit, and a second encoded signal is generated. Frame generation When encoding a signal transmission apparatus characterized by comprising a. 2. A frame length information extraction unit that extracts frame length information from the first encoded signal according to an output of the control unit, wherein the frame generation unit outputs the encoded information from the encoded information extraction unit. Combining the output of the encoded data extraction unit and updating the encoded information according to the output of the control unit and the output of the frame length information extraction unit to generate second encoded information. The encoded signal transmission device according to claim 1. 3. An additional information input unit for inputting additional information to the first coded signal, wherein the frame generation unit outputs the coded information extraction unit and the coded data extraction unit. The output is combined, the encoded information is updated according to the output of the control unit and the output of the frame length information extraction unit, the second encoded information is generated, and the first encoded signal is converted into the first encoded signal. The coded signal transmission device according to claim 2, wherein the additional information is superimposed on a correction portion generated when the coded signal of No. 2 is converted.