CN1547186A

CN1547186A - A reverberation generating circuit

Info

Publication number: CN1547186A
Application number: CNA2003101169790A
Authority: CN
Inventors: 程青云; 金传恩
Original assignee: Vimicro Corp
Current assignee: Vimicro Corp
Priority date: 2003-12-05
Filing date: 2003-12-05
Publication date: 2004-11-17
Anticipated expiration: 2023-12-05
Also published as: CN100342425C

Abstract

The invention discloses a kind of reverberation generating circuit, which includes a superposition synthesizing circuit, there has a feedback circuit between the output end and the input end of the superposition synthesizing circuit. There has a compressing circuit, a delay circuit, a decompressing circuit and an attenuation circuit in series in the feedback loop; the voice signal outputted by the output end of the superposition synthesizing circuit is compressed through the compressing circuit before passing through the delay circuit, the compressed voice data is transmitted to the delay circuit be memorized, when the voice data passes through the delay circuit and is delayed with preset time, the compressed data will be transmitted to the decompressing circuit by the delay circuit, the compressed data is decompressed by the decompressing circuit and carries on attenuation process; the circuit reduces the area of the circuit, reduces the hardware cost.

Description

A kind of reverberation generating circuit

Technical field

The present invention relates to the synthetic field of sound, particularly in the speech synthesizing device in order to the reverberation generating circuit of the reflection reverberation effect that produces.

Background technology

Reverb (reverberation) audio is a kind of reflection reverberation sound effect, it is through a cross section be reflected (decay has taken place the sound that reflects certainly) after simulated sound sends out, and then and the current sound mix sound effect together the time, such audio sounds the people more stereoscopic sensation, gives the sensation of a kind of spaciousness of people.

Realizing the scheme of Reverb audio in the prior art, mainly is the principle that adopts the time-delay stack, and the sound that at first allows is into delivered to a delay circuit, and the acoustic playback that mixes newly to come in that superposes is then gone out, and just can realize the Reverb audio so like this.As shown in Figure 1, the voice signal of the output terminal output of stack combiner circuit is sent to a delay circuit, by being transferred to attenuator circuit after the delay process, sue for peace in the voice signal stack that superposes combiner circuit and newly come in through the voice signal after the attenuator circuit processing, output terminal just can obtain having had the voice signal of Reverb effect like this, the United States Patent Office (USPO) patent No. is USP4, the description that 955,057 patent is detailed similar device.

But there is such shortcoming in the reverberation generating circuit that utilizes this loop to realize: the general delay circuit here need be used a block storage and come the stored sound data, if voice signal to be processed be 16 PCM formatted data, the sampled voice rate of playback is 48k/s, so we to realize 1 second effect the Reverb effect time, just need 48k 16 PCM data of storage 96k byte data just, therefore just need the big RAM of 96k, so jumbo RAM area is the same very big, so just make hardware cost too high, so common way is the Reverb effect that does not realize that 1 second is so long, perhaps reduce output sampling rate, so certainly will can influence to some extent the Reverb effect.

Summary of the invention

In order to solve problems of the prior art and deficiency, the object of the present invention is to provide a kind of reverberation generating circuit that has improved, described reverberation generating circuit has reduced the capacity of required storer, and then has also reduced the area of circuit, reduced hardware cost.

In order to realize the foregoing invention purpose, the present invention proposes following technical scheme:

A kind of reverberation generating circuit comprises: a stack combiner circuit, a delay circuit, an attenuator circuit; An input end of described stack combiner circuit receives a voice signal, this voice signal superposes from the voice signal of output terminal through importing with above-mentioned input end the stack combiner circuit behind the backfeed loop of described stack combiner circuit, is in series with a delay circuit and an attenuator circuit in the above-mentioned backfeed loop successively;

Its design feature is, also comprises a compressor circuit and a decompression circuit in described backfeed loop, and the input end of described compressor circuit connects the output terminal of stack combiner circuit, and the output terminal of compressor circuit connects the input end of delay circuit; The input end of described decompression circuit connects the output terminal of delay circuit, and the output terminal of described decompression circuit connects the input end of attenuator circuit.

The voice signal of the output terminal output of stack combiner circuit is before entering delay circuit, compress through described compressor circuit earlier, then the voice data after the compression being sent into delay circuit stores, after voice data has carried out the time-delay of the schedule time through delay circuit, delay circuit can be exported packed data to decompression circuit, and decompression circuit can be decompress reduction and then carry out attenuation processing of packed data.

Described compressor circuit and decompression circuit are respectively ADPCM compressor circuit and ADPCM decompression circuit.

The contrast prior art the invention has the advantages that:

Because scheme of the present invention has increased compressor circuit and decompression circuit in reverberation generating circuit, the voice data that feasible needs are stored in the delay circuit reduces greatly, so, not only reduce the capacity of required storer in the design and then also reduced the area of circuit, reduced hardware cost, simultaneously, also can effectively adapt to the sound increase of time expand.

But advantage of the present invention is not limited to the above-mentioned application of lifting, below in conjunction with accompanying drawing be not that certain embodiments comes the utility model is done more detailed explanation.

Description of drawings

Fig. 1 is a general reverberation generative circuit structural representation in the prior art;

Fig. 2 is a reverberation generative circuit structural representation of the present invention.

Embodiment

In the following description, known function or structure will no longer describe in detail, to avoid there be unnecessary obscuring with content of the present invention.

As shown in Figure 2, a kind of reverberation generating circuit comprises: 12, one attenuator circuits 14 of stack 10, one delay circuits of combiner circuit; An input end of described stack combiner circuit 10 receives a voice signal, this voice signal superposes from the voice signal of output terminal through importing with above-mentioned input end stack combiner circuit 10 behind the backfeed loop of described stack combiner circuit 10, is in series with a delay circuit 12 and an attenuator circuit 14 in the above-mentioned backfeed loop successively; In described backfeed loop, also comprise an ADPCM compressor circuit 11 and an ADPCM decompression circuit 13, the input end of described ADPCM compressor circuit 11 connects the output terminal of stack combiner circuit 10, and the output terminal of ADPCM compressor circuit 11 connects the input end of delay circuit 12; The input end of described ADPCM decompression circuit 13 connects the output terminal of delay circuit 12, and the output terminal of described ADPCM decompression circuit 13 connects the input end of attenuator circuit 14.What adopt in the present embodiment is the ADPCM compression, ADPCM (Adaptive DifferentialPulse Code Modulation), be called adaptive difference pulse code, it is a kind of lossy compression method, it has lost partial information, but owing to the insensitivity of people's ear to sound, suitable lossy compression method is little to the influence of audiovisual result of broadcast; The quantized value of ADPCM record is not the amplitude of each sampled point, but this amplitude and previous sampled point amplitude is poor.PCM to 16bitd compresses like this, and the quantization of each sampled point does not just need 16bit, can reduce the capacity of signal thus.Certainly, reverberation generating circuit of the present invention adopts other sound compression method and the device also can fine realization.

After the input end of stack combiner circuit 10 receives the voice signal of a PCM (pulse code modulation (PCM)) form, through its output terminal this voice signal is sent in the backfeed loop, this voice signal is before entering delay circuit 12, compress through described ADPCM compressor circuit 11 earlier, ADPCM compressor circuit 11 is 16 PCM data compression the data of position still less at first, the present invention adopts the ADPCM compression algorithm, data after the compression are 4, then the data after the compression are sent in the delay circuit 12 and stored, we will realize the time-delay of 1 second kind in this supposition, and our the sampled voice frequency of output is 48k/s, this delay circuit just needs the voice data after 48k of storage compressed so, it is the 24k byte, the storage unit that needs is 24k just also, same voice signal, if before not compressing, store, then need be up to the storage space of 96k byte data; After data have been carried out the time-delay of the schedule time through delay circuit 12, export packed datas to ADPCM decompression circuit 13 from delay circuit 12 again, ADPCM decompression circuit 13 can decompress packed data and be reduced to the data (these errors are within the imperceptible scope of people's ear) of approximate original sound, data after decompressing have been exactly real sound PCM data, its superposes synthetic through corresponding attenuator circuit 14 (decay in the simulated sound communication process) and the voice signal that newly enters stack combiner circuit 10, hold at OUT like this and just can hear the voice signal that has the Reverb effect.

In sum, reverberation generating circuit of the present invention, be not limited only to listed utilization in instructions and the embodiment, it can be applied to various suitable the present invention's field fully, for those skilled in the art, can easily realize additional advantage and make amendment, therefore under the situation of the spirit and scope of the universal that does not deviate from claim and equivalency range and limited, the examples shown that the present invention is not limited to specific details, representational equipment and illustrates here and describe.

Claims

1, a kind of reverberation generating circuit comprises: a stack combiner circuit, a delay circuit, an attenuator circuit; An input end of described stack combiner circuit receives a voice signal, this voice signal superposes from the voice signal of output terminal through importing with above-mentioned input end the stack combiner circuit behind the backfeed loop of described stack combiner circuit, is in series with a delay circuit and an attenuator circuit in the above-mentioned backfeed loop successively; It is characterized in that,

Also comprise a compressor circuit and a decompression circuit in described backfeed loop, the input end of described compressor circuit connects the output terminal of stack combiner circuit, and the output terminal of compressor circuit connects the input end of delay circuit; The input end of described decompression circuit connects the output terminal of delay circuit, and the output terminal of described decompression circuit connects the input end of attenuator circuit.

2, reverberation generating circuit according to claim 1 is characterized in that, described compressor circuit and decompression circuit are respectively ADPCM compressor circuit and ADPCM decompression circuit.