JPH0836399A - Processing device for audio coded data - Google Patents

Abstract

PURPOSE:To efficiently and arbitrarily set frequency characteristics and to prevent degradation in the tone quality without completely decoding from a bit stream condition by providing a control means and a format means. CONSTITUTION:A deformat section 3 outputs band signals Q0<-1> to Q31<-1>, which are inverse-quantization-processed, to a control means 1. The signals are supplied to respective multipliers 120 to 1231 of the means 1. A gain control section 11 of the means 1 controls each of the multipliers 120 to 1231 and the signals Q0<-1> to Q31<-1> from the section 3 are multiplied by gains. The multipliers 120 to 1231 output gain-multiplied signals Q0<-1> to Q31<-1> to a format means 2. The means 2 quantization-processes the signals Q0<-1> to Q31<-1> and assembles bit stream condition data. Thus, the gains, multiplied to each band signal, are individually changed under the control of the section 11 and a frequency equalizing process, which changes the frequency characteristics of inputted audio data, is executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an audio coded data processing apparatus for processing audio data obtained by frequency-decomposing digital audio data and coding the audio data. The present invention relates to a device for processing audio-encoded data, which is suitable for use in the digital equipment.

[0002]

2. Description of the Related Art Generally, there are various high-efficiency coding methods for reducing the data amount of digital audio data, for example, a block frequency band division method, so-called transform coding (transform coding), , A non-blocking frequency band division method, so-called band division coding (subband coding: SBC), and the like.

These high-efficiency coding techniques reduce redundant information by utilizing the property of uneven distribution in the frequency axis direction.

For example, the band division coding method is shown in FIG.
As shown in FIG. 3, an encoding processing unit 100 that divides into frequency bands and encodes, a bitstream processing unit 200 that performs assembly processing into a bitstream and decomposition processing from the bitstream, and decodes into audio data. It is composed of a decoding processing unit 300.

The encoding processing unit 100 divides the input audio data X (n) of a plurality of channels into M frequency bands for each channel and encodes them.

At the time of encoding, the bit stream processing unit 200 rearranges the band signals of a plurality of channels encoded by the encoding processing unit 100 into a bit stream format and assembles them into one data.
Further, at the time of decoding, the bit stream state is decomposed and distributed to the data strings of each band signal.

The decoding processing unit 300 decodes each band signal decomposed by the bit stream processing unit 200 into audio data Y (n).

Here, the system configuration of the coding / decoding apparatus to which the band division coding method shown in FIG. 6 is applied will be described with reference to FIG. 7. The coding processing unit 100 shown in FIG. , An analysis filter bank 101 for dividing the frequency band into M frequency bands, and a quantizer 102 for performing a quantization process for each of the divided band signals.

The bit stream processing section 200 shown in FIG. 6 has a memory 201 for recording the data assembled in the bit stream state.

Further, the decoding processing section 300 shown in FIG.
Is an inverse quantizer 301 that performs an inverse quantization process on each band signal.
And a synthesis filter bank 302 for synthesizing the inversely requantized band signals.

The analysis filter bank 101, for example, audio data X (n), which is a wide signal having a sampling frequency fs, is divided into M equal sampling frequencies fs.
/ M subbands.

The quantizer 102 performs a bit allocation process for assigning a quantization level so that the total data amount becomes a constant amount according to the data amount of each band signal divided by the analysis filter bank 101, Quantization processing is performed on the data of each band signal at the assigned quantization level.

The memory 201 includes the quantizer 10
Data in which each band signal quantized by 2 is assembled into a bit stream state is recorded.

The inverse quantizer 301 performs an inverse quantization process on each decomposed band signal according to the quantization level information.

The synthesizing filter bank 302 synthesizes the respective band signals subjected to the inverse quantization processing by the inverse quantizer 301 and decodes them into audio data.

The operation of the encoding / decoding device having the above-mentioned configuration will be described with reference to FIG.

At the time of encoding, the analysis filter bank 101
For example, divides audio data of a plurality of channels from a digital device such as an editing machine or a mixer into a plurality of frequency bands for each channel, and supplies each of the divided band signals to the quantization processing unit 102 (step 51).

The quantization processing unit 102 performs bit allocation processing on each band signal of a plurality of channels from the analysis filter bank 101 for each channel (step 52), and processes each band signal at the assigned quantization level. Quantization processing is performed (step 53). Then, the quantized band signals and the quantization level information are supplied to the bitstream processing unit 200.

The bit stream processing section 200 assembles the band signals of a plurality of channels which have been quantized by the quantization processing section 102 and the quantization level information into a bit stream according to a predetermined format (step 54). ) Recording in the memory 201.

The data in the bit stream state recorded in the memory 201 is an ECC (Error Ch) (not shown) to which information for error correction is added.
Ecking and Correcting) block, and then recorded on a recording medium or transmitted.

Next, at the time of decoding, the error-corrected data in the bit stream state is decomposed by the bit stream processing unit 200 and distributed to the data string of each band signal for each channel (step 55). Then, each decomposed band signal is supplied to the inverse quantization processing unit 302.

The dequantization processing unit 302 obtains the quantization level from the quantization level information of the data in the bitstream state (step 56), and each channel from the bitstream processing unit 200 according to the quantization level. Inverse quantization processing is applied to each band signal (step 57).
Then, the dequantized band signals are supplied to the synthesis filter bank 301.

The synthesis filter bank 301 synthesizes the band signals of the respective channels subjected to the dequantization processing from the dequantization processing unit 302, and outputs them as audio data to a digital device such as an editor or a mixer. Output (step 58).

The frame cycle control at the time of the above-mentioned encoding / decoding processing is performed by, for example, the timing control unit 59 having a pulse oscillator. The system controller 60 controls input / output data between the encoding / decoding device and the ECC block or digital device.
Done in.

It is expected that the number of digital devices for recording, transmitting, editing, or mixing processing of data encoded by the encoding / decoding device having the above-described configuration will increase in the future. .

[0026]

However, the gain control, the mix processing, and the like for the encoded data in the bit stream state are performed by the digital device as described above. That is, in the case of performing the gain control or the mixing process, it is necessary to once decode the audio data, perform the gain control or the mixing process, perform the encoding again, and restore the bit-bitstream state data.

That is, the number of encoding / decoding processes increases, and the analysis filter bank 101 and the synthesizing filter bank 301 as described above are passed by the number of times. As a result, distortion was increased and it was not possible to prevent sound quality deterioration.

Further, as described above, since the number of encoding / decoding processes is large, the time required for signal processing, that is, the so-called system delay amount becomes large, so that gain control and mix processing can be performed efficiently. I couldn't.

Therefore, the present invention has been made in view of the above-mentioned conventional circumstances, and has the following objects.

That is, an object of the present invention is to perform audio processing such as gain control and mix processing efficiently without completely decoding from the state of a bit stream, and to prevent deterioration of sound quality. An object is to provide a processing device for digitized data.

[0031]

In order to solve the above problems, an audio coded data processing apparatus according to the present invention is an audio code for operating audio data coded by being divided into a plurality of frequency bands. A device for processing encoded data, comprising: a control unit that performs gain control for each encoded band signal, and a formatting unit that assembles each band signal that has been gain controlled by the control unit into a bitstream state. It is characterized by including.

An audio coded data processing apparatus according to the present invention is an audio coded data processing apparatus for operating audio data of a plurality of channels which are coded by being divided into a plurality of frequency bands. Control means for performing gain control on each band signal of the plurality of channels, mix means for mixing each band signal of the plurality of channels for which gain control is performed by the control means, and each band signal mixed by the mixing means And a formatting means for assembling the above into a bit stream state.

Further, in the audio coded data processing apparatus according to the present invention, the control means may change the gain ratio of each band signal of each channel to be mixed by the mixing means so that each channel signal is mixed. It is characterized in that the gain ratio of each band signal is controlled.

[0034]

In the audio coded data processing apparatus according to the present invention, the control means controls the gain of each of the coded band signals with respect to the audio data coded by being divided into a plurality of frequency bands. Give. The formatting means assembles each band signal subjected to the gain control by the control means into a bit stream state.

In the audio coded data processing device according to the present invention, the control means divides the audio data of a plurality of channels divided into a plurality of frequency bands and coded into each of the plurality of coded channels. Gain control is applied to the band signal. The mixing means mixes the band signals of the plurality of channels for which the gain control has been performed by the control means. The formatting means assembles the band signals mixed by the mixing means into a bitstream state.

Further, in the audio coded data processing device according to the present invention, the control means controls the band ratio of each channel to be mixed by the mixing means by changing the gain ratio of each band signal. The gain ratio of each band signal is controlled.

[0037]

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

First, an audio coded data processing apparatus according to the first embodiment of the present invention will be described.

The audio coded data processing apparatus according to the first embodiment of the present invention shown in FIG. 1 has a control means 1 for performing a gain control for each coded band signal, and a gain by the control means 1. Formatting means 2 for assembling each controlled band signal into a bit stream state.

Further, the audio coded data processing apparatus is provided with the input bit stream state data 31.
The deformatter 3 is provided for decomposing and dividing the data into a data string of each band signal.

Here, the input bit stream state data 31 is, for example, coded by a band division coding method and assembled into a bit stream state according to a predetermined format. That is, the audio data is divided into a plurality of frequency bands, and each band signal that has been quantized at the quantization level assigned by the bit allocation process is divided into bits according to the data amount of each divided band signal. It is assembled into a stream.

For example, as shown in FIG. 2, the data in the bit stream state generated by the band division coding method with the number of divisions of 32 and the code length of 320 samples is 10 samples D of 32 band signals Sb0 to Sb31, respectively. 1 from _{0 to} D ₉
It consists of two band signals.

The band signals Sb0 to Sb31 contain information ALLOC indicating the quantization level at the time of quantization.
And information indicating the maximum value of data in each band signal, so-called scale factor SF, is recorded.

The bit stream state data 31 formatted as described above is input to the deformatter 3.

The reformatting unit 3 decomposes the input data 31 in the bit stream state and converts it into a data string of each band signal. Further, the deformatter 3 is provided with the information ALLOC indicating the above-mentioned quantization level recorded in the data 31 in the bitstream state.
Then, a quantization level is obtained from the above, and inverse quantization processing is performed for each band signal according to the above quantization level.

[0046] The control unit 1 includes a multiplier 12 _{0-12 31} applying a gain in each band signal Q ^-1 ₀ to Q ^-1 _31, which are inverse quantized from the deformat unit 3, the multiplier 12 ₀
And a gain control unit 11 for controlling each of 12 to ₃₁ . The multiplier 12 _{0-12 3 1} is obtained by each corresponding to each band signal Q ^-1 ₀ ~Q ^-1 ₃₁ from the deformat unit 3.

That is, the gain control section 11 controls the multipliers 12 _{0 to} 12 ₃₁ , and the multipliers 12 _{0 to} 12 ₃₁ are output from the deformat section 3 according to the control of the gain control section 11. that by applying a gain to each subband signal Q ^-1 ₀ ~Q ^-1 _31, and thus to control the frequency characteristic of the audio data outputted from the processing unit of the audio coded data.

[0048] The formatting means 3, each band signal gain control is performed by the control unit 1 Q ^-1 ₀ ~Q ^-1
Performs each respective bit allocation process _31, the respective band signal Q ^-1 ₀ to Q ^-1 ₃₁ quantization levels allocated for quantizing. Then, the quantized band signals Q _{0 to} Q ₃₁ ,
And, the information indicating the quantization level is assembled into a bitstream state according to a predetermined format.

The operation of the audio coded data processing apparatus having the above configuration will be described.

The de-formatting unit 3 decomposes the input bit stream state data 31 into a data string of each band signal, and the quantum recorded in each bit stream state data 31 together with each band signal encoded. Inverse quantization processing is performed on each of the band signals based on the information ALLOC indicating the quantization level. Then, the de-formatting unit 3 outputs the respective band signal Q ^-1 ₀ ~Q ^-1 ₃₁ subjected to the inverse quantization processing to the control unit 1.

[0051] The de-formatting unit 3 each band signal Q ^-1 ₀ to Q ^-1 ₃₁ output from is respectively supplied to the multipliers 12 ₀ to 12 ₃₁ of the corresponding said control means 1.

At this time, the gain control section 1 of the control means 1
1 controls each of the multipliers 12 _{0 to} 12 ₃₁ .

[0053] The multiplier 12 _{0-12 31,} under control of the gain control unit 11 applies a gain to each subband signal Q ^-1 ₀ to Q ^-1 ₃₁ from the deformat unit 3. Then, the multiplier 12 _{0-12 31} outputs each band signal Q ^-1 ₀ to Q ^-1 ₃₁ multiplied by the gain to the formatting means 2.

The formatting means 2 includes the multiplier 1
2 each band signal gain is multiplied from _{0 ~12 31} Q ^-1 ₀
To Q ^-1 ₃₁ are quantized, and the quantized band signals Q _{0 to} Q ₃₁ are assembled into bit stream state data.

As described above, in this audio coded data processing apparatus, the gain control is performed for each coded band signal without completely decoding from the state of the bit stream. For example, the frequency equalizing process for varying the frequency characteristic of the input audio data can be performed by separately changing the gain applied to each band signal under the control of the gain control unit 11. Further, since the analysis filter for dividing into a plurality of frequency bands and the synthesis filter for synthesizing the respective divided band signals do not pass, the signal distortion due to the calculation accuracy in the filter processing can be eliminated. Furthermore, the time required for signal processing can be significantly reduced.

Next, an audio coded data processing apparatus according to the second embodiment of the present invention will be described.

The audio coded data processing apparatus according to the second embodiment of the present invention shown in FIG. 3 includes, for example, a control means 6 for performing gain control on coded band signals of two channels CH1 and CH2. , The above gain control was applied 2
It comprises a mixing means 7 for mixing the respective band signals of the channels CH1 and CH2, and a formatting means 8 for assembling the respective band signals mixed by the mixing means 7 into data in a bit stream state.

Further, the audio coded data processing device is provided with a de-formatting unit 5 for decomposing the input bit stream state data of the two channels CH1 and CH2 into a data string of each band signal for each channel. There is.

Here, input two channels CH1,
The data 51 and 52 of the CH2 bit stream state are
The data has the same format as the data shown in FIG. 2, and is coded by the band division coding method for each channel and assembled into a bit stream state according to a predetermined format. The reformatting unit 5 receives the input channel CH1.
The data 51 of the bit stream state and the data 52 of the bit stream state of the channel CH2 are decomposed for each channel and converted into the data string of each band signal subjected to the encoding process.

Further, the reformatting unit 5 obtains the quantization level from the information ALLOC indicating the above-mentioned quantization level recorded in the data 51 and 52 in the bit stream state, and each of them is determined in accordance with the quantization level. Inverse quantization processing is performed for each band signal.

The control means 6 multiplies a gain by the dequantized band-passed channel signals Q ^-1 _{100 to} Q ^-1 ₁₃₁ of the channel CH1 from the reformatting unit 5.
_{100 to} 62 ₁₃₁ and each band signal Q ^-1 of the channel CH2 which has been subjected to the inverse quantization process from the deformatting unit 5
Multiplier 63 that multiplies the gain from _{200 to} Q ^-1 ₂₃₁ 63 _{200 to} 63 _{2 31}
And the multipliers 62 _{100 to} 62 ₁₃₁ and the multiplier 63
_The gain control unit 61 controls each of _{200 to} 63 ₂₃₁ .

The multipliers 62 _{100 to} 62 ₁₃₁ have the band signals Q of the channel CH1 from the reformatting unit 5, respectively.
^-1 _{100 to} Q ^-1 ₁₃₁ respectively, and the multipliers 63 _{200 to} 63 ₂₃₁ correspond to the band signals Q ^-1 _{200 to} Q ^-1 ₂₃₁ of the channel CH2 from the reformatting unit 5. Corresponding to each.

That is, the gain control unit 61 controls the multipliers 62 _{100 to} 62 ₁₃₁ and the multipliers 63 _{200 to} 63 ₂₃₁ respectively, and the multipliers 62 _{100 to} 62 ₁₃₁ and the multiplier 63 ₂₀₀ to 63 ₂₃₁ is a channel C output from the reformatting unit 5 under the control of the gain control unit 61.
A gain is applied to each of the band signals Q ^-1 _{100 to} Q ^-1 _{131 of} H1 and CH2 and each band signal Q ^-1 _{200 to} Q ^-1 ₂₃₁ .

Here, the gain control section 61 controls the gain GA of each band signal Q ^-1 _{100 to} Q ^-1 ₁₃₁ of the channel CH1.
IN1 and band signals Q ^-1 _{200 to} Q of channel CH2
The gain GAIN2 of ^-1 _{23 1} (hereinafter referred to as the gain ratio) is controlled so as to be changed. For example, as shown in FIG. 4, gain GAIN1: gain GAIN2 = 1: 0
When the control is performed so that the band signals of the channel CH1 to which the gain GAIN1 is applied by the mixing means 7 and the channel C to which the gain GAIN2 is applied are obtained.
By mixing with each band signal of H2, the audio data of the channel CH1 is output from the mixing means 7 as the audio data of the channel CH3.

Alternatively, gain GAIN1: gain GAIN
When control is performed so that 2 = 0.5: 0.5, the channels CH1 and CH2 are mixed from the mixing means 7 by being mixed by the mixing means 7 in the same manner as the above case. The synthesized audio data is output as the audio data of channel CH3.

When it is desired to control the output level of the channel CH1, the control means 6 changes the gain G applied to each band signal to 0 to 1 or 1 to 0,
By controlling the gain GAIN1: gain GAIN2 = G: 0, the output level of the channel CH1 can be controlled.

Alternatively, in the case of performing crossfade processing between two data, similarly to the above-mentioned output level control,
Gain GAIN1: Gain GAIN2 = G: (1-G)
The level can be adjusted so as to gradually switch from the channel CH1 to the channel CH2 or from the channel CH2 to the channel CH1 by controlling such that

As described above, the gain controller 61
Changes the gain ratio for the channel CH1 and the channel CH2 and applies a gain corresponding to the gain ratio to each band signal of each channel.

The mixing means 7 comprises adders 71 _{0 to} 71 _0.
Includes a 1 _31, each band signal Q ^-1 ₀ to Q ^-1 ₃₁ of channels CH1, CH2 gain is multiplied in accordance with the arbitrary gain ratio by the control unit 6 as described above, and, each band The signals Q ^-1 _{200 to} Q ^-1 ₂₃₁ are mixed.

More specifically, for example, the channel CH1 from the multiplier 62 ₁₀₀ is included in the adder 71 _0.
A band signal Q ^-1 ₁₀₀ of band signals Q ^-1 ₂₀₀ channel CH2 from the multiplier 63 ₂₀₀ is supplied to the adder 71 _1, the channel CH1 from the multiplier 62 _{10 1}
A band signal Q ^-1 ₁₀₁ of band signals Q ^-1 ₂₀₁ channel CH2 from the multiplier 63 ₂₀₁ is supplied. Thus, the adder 71 _{0-71 31} is one corresponding to each band signal of each channel, it is to add the band signal of each channel supplied.

As described above, this mixing means 7
Mixes each band signal of each channel whose gain ratio has been changed by the control means 5.

The formatting means 8 quantizes the band signals mixed by the mixing means 7 and converts the quantized band signals Q _{0 to} Q ₃₁ into bit stream state data 81. Assembling and outputting the assembled data 81 as the data 81 of the channel CH3.

The operation of the audio coded data processing apparatus shown in FIG. 3 and configured as described above will be described with reference to FIG. For example, error-corrected bit stream data 51 of the channel CH1 and data 52 of the channel CH1 are input to the reformatting unit 5 from the ECC block.

The above-mentioned reformatting section 5 uses the channel 1
Data 51 of each band signal is decomposed into a data string of each band signal (step 501), and a quantum is obtained from the information ALLOC indicating the quantization level recorded together with each band signal encoded in the data 51 in the bit stream state. The conversion level is obtained (step 502). Then, dequantization processing is performed on each of the band signals according to the quantization level (step 503), and the channel CH subjected to the dequantization processing is performed.
Each band signal Q ^-1 _{100 to} Q ^-1 ₁₃₁ of ¹ is output to the control means 6.

Further, the reformatting unit 5 decomposes the data 52 of the channel 2 into a data string of each band signal (step 511) and encodes each band signal into the data 52 in the bit stream state. The quantization level is obtained from the information ALLOC indicating the quantization level recorded together with (step 512). Then, the respective band signals are subjected to inverse quantization processing in accordance with the quantization level (step 513), and the respective band signals Q ^-1 _{200 to} Q ^-1 ₂₃₁ of the channel CH2 subjected to the inverse quantization processing are controlled. Means 6
Output to.

The control means 6 controls each band signal Q ^-1 ₁₀₀ of the channel CH1 from the reformatting section 5 according to the gain ratio while controlling according to an arbitrary gain ratio.
~ Q ^{- 1} ₁₃₁ multiplied by gain GAIN1 and channel CH
Each band signal Q ^-1 ₂₀₀ ~Q ^-1 _{2 31} 2 multiplied by gain GAIN2. Then, the band signals Q ^-1 _{100 to} Q ^-1 _{131 of} the channel CH1 multiplied by the gain GAIN1 and the gain G
Each band signal Q ^{-1 of} channel CH2 multiplied by AIN2
_{200 to} Q ^-1 ₂₃₁ is output to the mixing means 7.

The mixing means 7 controls the band signals Q of the respective channels to which the gain control from the control means 6 is applied.
^-1 _{100 to} Q ^-1 ₁₃₁ and each band signal Q ^-1 _{200 to} Q ^-1 ₂₃₁ are mixed. Then, the mix unit 7 outputs each band signal Q ^-1 ₀ ~Q ^-1 ₃₁ that the mix formatting means 8.

[0078] The formatting means 8, each band signal has been mixed from the mixing means 7 Q ^-1 ₀ ~Q ^-1 ₃₁
Bit allocation processing to each of the
1) Quantize the data of each band signal at the assigned quantization level (step 802). Then, the quantized band signals and the information indicating the quantization level are assembled into a bit stream state according to a predetermined format, and output to the ECC block as the bit stream state data 81 of the channel CH3. .

As described above, in this audio coded data processing apparatus, since it is possible to mix by changing the gain ratio of each channel to be mixed, that is, the gain can be controlled, the crossfade processing,
Alternatively, the output level of audio data can be controlled.

Although the audio coded data processing apparatus shown in FIG. 1 and FIG. 3 is provided with a large number of multipliers and adders, it is possible to perform multiplication by performing time division processing. , The number of adders can be reduced. As a result, the circuit configuration of the audio coded data processing device can be simplified.

Further, in the audio coded data processing apparatus shown in FIGS. 1 and 3, the data processing of audio data coded by the band division coding method is performed. It can also be applied to audio data coded by all other coding methods for linear processing and division.

[0082]

In the audio coded data processing apparatus according to the present invention, the control means divides the audio data coded into a plurality of frequency bands into coded band signals. Apply gain control. The formatting means assembles each band signal subjected to the gain control by the control means into a bit stream state. By this means, it is possible to efficiently set arbitrary frequency characteristics without completely decoding from the bitstream state, and prevent deterioration of sound quality.

In the audio coded data processing device according to the present invention, the control means divides the audio data of a plurality of channels divided into a plurality of frequency bands and coded into each of the plurality of coded channels. Gain control is applied to the band signal. The mixing means mixes the band signals of the plurality of channels for which the gain control has been performed by the control means. The formatting means assembles the band signals mixed by the mixing means into a bitstream state. As a result, it is possible to efficiently perform gain control without completely decoding the bitstream state and prevent deterioration of sound quality.

Also, in the audio coded data processing apparatus according to the present invention, the control means of each channel mixes by changing the gain ratio of each band signal of each channel mixed by the mixing means. The gain ratio of each band signal is controlled. As a result, the crossfade process can be efficiently performed.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a device for processing audio coded data according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a data structure assembled into a bitstream state.

FIG. 3 is a diagram showing the configuration of a device for processing audio coded data according to a second embodiment of the present invention.

FIG. 4 is a diagram for explaining control of a gain ratio.

FIG. 5 is a diagram for explaining an operation of the audio coded data processing device.

FIG. 6 is a diagram showing a configuration of a band division encoding method.

FIG. 7 is a diagram showing a system configuration of an encoding / decoding device to which the band division encoding method is applied.

FIG. 8 is a diagram for explaining the operation of the encoding / decoding device.

[Explanation of symbols]

 1,6 Control means 2,8 Formatting means 3,5 Deformatting section 7 Mixing means

Claims (3)

[Claims] 1. A device for processing audio coded data, which operates audio data coded by being divided into a plurality of frequency bands, and a control means for performing gain control for each of the coded band signals. A device for processing audio coded data, comprising: a format unit for assembling each band signal subjected to gain control by the control unit into a bit stream state. 2. A device for processing audio coded data, which operates audio data of a plurality of channels which are divided into a plurality of frequency bands and coded, wherein gain control is performed on each of the coded band signals of the plurality of channels. A mixing means for mixing the band signals of a plurality of channels for which gain control has been performed by the control means, and a formatting means for assembling the band signals mixed by the mixing means into a bit stream state. An apparatus for processing audio-encoded data, comprising: 3. The control means controls the gain ratio of each band signal of each channel so that the band ratio of each band signal of each channel mixed by the mixing means is changed to mix. Claim 2
A device for processing audio coded data according to claim 1.