Hearing compensation system incorporating signal processing techniques
First Claim
1. An audio output device, comprising:
- an acoustic input transducer for converting input acoustical energy into output electrical signals corresponding to the input acoustical energy;
a plurality of audio bandpass filters coupled to receive said electrical signals, each of said audio bandpass filters having an output; and
a plurality of multiplicative automatic gain control (MAGC) circuits coupled to a respective output of one of said plurality of audio bandpass filters, at least one of said MAGC circuits including a hearing compensation circuit and a noise suppression circuit, and wherein at least one of said MAGC circuits include;
a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output;
a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude;
a noise estimation circuit for obtaining an estimate of noise; and
a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude;
wherein an acoustic signal having approximately a constant amplitude for a period of a predetermined amount of time is attenuated through interaction of said hearing compensation circuit and said noise suppression circuit.
1 Assignment
0 Petitions
Accused Products
Abstract
A hearing compensation system comprises a plurality of bandpass filters having an input connected to an input transducer and each bandpass filter having an output connected to the input of one of a plurality of multiplicative automatic gain control (MAGC) circuits whose outputs are summed together and connected to the input of an output transducer. The MAGC circuits attenuate acoustic signals having a constant background level without the loss of speech intelligibility. The identification of the background noise portion of the acoustic signal is made by the constancy of the envelope of the input signal in each of the several frequency bands. The background noise that will be suppressed includes multi-talker speech babble, fan noise, feedback whistle, florescent light hum, and white noise. For use in the consumer electronics field background acoustic noise may be sensed and used to adjust gain in the various MAGC circuits so as to improve a user'"'"'s listening experience, whether the user is hearing impaired or not.
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Citations
68 Claims
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1. An audio output device, comprising:
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an acoustic input transducer for converting input acoustical energy into output electrical signals corresponding to the input acoustical energy; a plurality of audio bandpass filters coupled to receive said electrical signals, each of said audio bandpass filters having an output; and a plurality of multiplicative automatic gain control (MAGC) circuits coupled to a respective output of one of said plurality of audio bandpass filters, at least one of said MAGC circuits including a hearing compensation circuit and a noise suppression circuit, and wherein at least one of said MAGC circuits include; a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output; a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude; a noise estimation circuit for obtaining an estimate of noise; and a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude; wherein an acoustic signal having approximately a constant amplitude for a period of a predetermined amount of time is attenuated through interaction of said hearing compensation circuit and said noise suppression circuit. - View Dependent Claims (2, 3, 4, 5)
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6. An audio output device, comprising:
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an input transducer for converting input acoustical energy into output electrical energy corresponding to the input acoustical energy; a plurality of audio bandpass filters coupled to the output of said input transducer; a plurality of multiplicative automatic gain control (MAGC) circuits, each of said MAGC circuits coupled to an output of one of said audio bandpass filters, at least one of said MAGC circuits including a hearing compensation circuit and a noise estimation circuit, and wherein at least one of said MAGC circuits include; a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output; a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude; a noise estimation circuit for obtaining an estimate of noise; and a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude; an output transducer responsive to said plurality of MAGC circuits, wherein noise present in the acoustical energy is attenuated through interaction of said hearing compensation circuit and said noise estimation circuit. - View Dependent Claims (7)
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8. An audio output device, comprising,
an input transducer for converting input acoustical energy into output electrical signals corresponding to the input acoustical energy; -
a plurality of audio bandpass filters coupled to the output of said input transducer; a plurality of multiplicative automatic gain control (MAGC) circuits, each of said MAGC circuits coupled to an output of one of said audio bandpass filters, at least one of said MAGC circuits including a hearing compensation circuit and a noise estimation circuit, and wherein at least one of said MAGC circuits include; a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output; a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude; a noise estimation circuit for obtaining an estimate of noise; and a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude; an output transducer responsive to said plurality of MAGC circuits, wherein an acoustic signal having approximately a constant amplitude for a period of a predetermined amount of time is attenuated through interaction of said hearing compensation circuit and said noise estimation circuit.
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9. A hearing aid device, comprising:
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an input transducer for converting input acoustical energy into output electrical signals corresponding to the input acoustical energy; a plurality of audio bandpass filters coupled to receive said output electrical signals, each of said audio bandpass filters having an output; a plurality of multiplicative automatic gain control (MAGC) circuits, each of said MAGC circuits coupled to an output of one of said plurality of audio bandpass filters, at least one of said MAGC circuits including a hearing compensation circuit and a noise suppression circuit, and wherein at least one of said MAGC circuits include; a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output; a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude; a noise estimation circuit for obtaining an estimate of noise; and a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude; an output transducer responsive to said plurality of multiplicative automatic gain control (AGC) circuits, wherein an acoustic signal having approximately a constant amplitude for a period of a predetermined amount of time is attenuated through interaction of said hearing compensation circuit and said noise suppression circuit. - View Dependent Claims (10, 11, 12)
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13. A hearing aid device, comprising:
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an input transducer for converting input acoustical energy into output electrical energy corresponding to the input acoustical energy; a plurality of audio bandpass filters coupled to the output of said input transducer; a plurality of multiplicative automatic gain control (MAGC) circuits, each of said MAGC circuits coupled to an output of one of said audio bandpass filters, at least one of said MAGC circuits including a hearing compensation circuit and a noise estimation circuit, and wherein at least one of said MAGC circuits include; a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output; a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude; a noise estimation circuit for obtaining an estimate of noise; and a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude; an output transducer responsive to said plurality of MAGC circuits, wherein noise present in the acoustical energy is attenuated through interaction of said hearing compensation circuit and said noise estimation circuit. - View Dependent Claims (14)
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15. A hearing aid output device, comprising,
an input transducer for converting input acoustical energy into output electrical signals corresponding to the input acoustical energy; -
a plurality of hearing aid bandpass filters coupled to the output of said input transducer; a plurality of multiplicative automatic gain control (MAGC) circuits, each of said MAGC circuits coupled to an output of one of said hearing aid bandpass filters, at least one of said MAGC circuits including a hearing compensation circuit and a noise estimation circuit, and wherein at least one of said MAGC circuits include; a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output; a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude; a noise estimation circuit for obtaining an estimate of noise; and a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude; an output transducer responsive to said plurality of MAGC circuits, wherein an acoustic signal having approximately a constant amplitude for a period of a predetermined amount of time is attenuated through interaction of said hearing compensation circuit and said noise estimation circuit.
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16. An audio output device, comprising:
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an input transducer for converting input acoustical energy into output electrical signals corresponding to the input acoustical energy; a multiplicative automatic gain control (MAGC) circuit coupled to said input transducer, said MAGC circuit including a high pass filter having an output, a low pass filter having an output, the output of said low pass filter being amplified by a factor of K, and a noise suppression circuit having an output; and an output transducer responsive to said plurality of MAGC circuits, wherein the amplified output of said low pass filter and the output of the noise suppression circuit are linearly combined to produce a first signal, the output of said high pass filter is linearly combined with the first signal; and an acoustic signal having approximately a constant amplitude for a period of a predetermined amount of time is attenuated through interaction of said high pass filter, said low pass filter and said noise suppression circuit. - View Dependent Claims (17, 18)
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19. An audio output device, comprising:
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an input transducer for converting input acoustical energy into output electrical signals corresponding to the input acoustical energy; a plurality of audio bandpass filters coupled to receive said electrical signals, each of said audio bandpass filters having an output; a plurality of multiplicative automatic gain control (MAGC) circuits each having at least one input and at least one output, an input of each of said MAGC circuits coupled to an output of one of said plurality of audio bandpass filters, at least one of said MAGC circuits comprising a hearing compensation circuit and a noise suppression circuit, and wherein at least one of said MAGC circuits include; a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output; a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude; a noise estimation circuit for obtaining an estimate of noise; and a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude; an output transducer responsive to said outputs of said plurality of MAGC circuits; wherein an acoustic signal having approximately a constant amplitude for a period of a predetermined amount of time is attenuated through interaction of said hearing compensation circuit and said noise suppression circuit. - View Dependent Claims (20, 21, 22, 23, 24, 25, 26, 27, 28)
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29. An audio output device, comprising:
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an input transducer for converting input acoustical energy into output electrical energy corresponding to the input acoustical energy; a plurality of audio bandpass filters coupled to the output of said input transducer; a plurality of multiplicative automatic gain control (MAGC) circuits, each having at least one input and at least one output, an input of each of said MAGC circuits coupled to an output of one of said audio bandpass filters, at least one of said MAGC circuits including a hearing compensation circuit and a noise estimation circuit, and wherein at least one of said MAGC circuits include; a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output; a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude; a noise estimation circuit for obtaining an estimate of noise; and a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude; an output transducer responsive to said plurality of MAGC circuits, wherein noise present in the acoustical energy is attenuated through interaction of said hearing compensation circuit and said noise estimation circuit. - View Dependent Claims (30)
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31. An audio output device, comprising:
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an input transducer for converting input acoustical energy into output electrical signals corresponding to the input acoustical energy; a plurality of audio bandpass filters coupled to the output of said input transducer; a plurality of multiplicative automatic gain control (MAGC) circuits, each having at least one input and at least one output, an input of each of said MAGC circuits coupled to an output of one of said audio bandpass filters, at least one of said MAGC circuits including a hearing compensation circuit and a noise estimation circuit, and wherein at least one of said MAGC circuits include; a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output; a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude; a noise estimation circuit for obtaining an estimate of noise; and a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude; an output transducer responsive to said plurality of multiplicative MAGC circuits, wherein an acoustic signal having approximately a constant amplitude for a period of a predetermined amount of time is attenuated through interaction of said hearing compensation circuit and said noise estimation circuit.
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32. A hearing aid device comprising:
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an input transducer for converting input acoustical energy into output electrical signals corresponding to the input acoustical energy; a plurality of audio bandpass filters coupled to receive said electrical signals, each of said audio bandpass filters having an output; a plurality of multiplicative automatic gain control (MAGC) circuits each having at least one input and at least one output, an input of each of said MAGC circuits coupled to an output of one of said plurality of audio bandpass filters, at least one of said MAGC circuits including a hearing compensation circuit and a noise suppression circuit, and wherein at least one of said MAGC circuits include; a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output; a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude; a noise estimation circuit for obtaining an estimate of noise; and a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude; an output transducer responsive to said outputs of said plurality of (MAGC) circuits; wherein an acoustic signal having approximately a constant amplitude for a period of a predetermined amount of time is attenuated through interaction of said hearing compensation circuit and said noise suppression circuit. - View Dependent Claims (33, 34, 35, 36, 37, 38, 39)
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40. A hearing aid device comprising:
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an input transducer for converting input acoustical energy into output electrical energy corresponding to the input acoustical energy; a plurality of audio bandpass filters coupled to the output of said input transducer; a plurality of multiplicative automatic gain control (MAGC) circuits, each having at least one input and at least one output, an input of each of said MAGC circuits coupled to an output of one of said audio bandpass filters, at least one of said MAGC circuits including a hearing compensation circuit and a noise estimation circuit, and wherein at least one of said MAGC circuits include; a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output; a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude; a noise estimation circuit for obtaining an estimate of noise; and a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude; an output transducer responsive to output of said plurality of MAGC circuits, wherein noise present in the acoustical energy is attenuated through interaction of said hearing compensation circuit and said noise estimation circuit. - View Dependent Claims (41, 42)
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43. A hearing aid device comprising:
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an input transducer for converting input acoustical energy into output electrical signals corresponding to the input acoustical energy; a plurality of audio bandpass filters coupled to the output of said input transducer; a plurality of multiplicative automatic gain control (MAGC) circuits, each having at least one input and at least one output, an input of each of said MAGC circuits coupled to an output of one of said audio bandpass filters, at least one of said MAGC circuits including a hearing compensation circuit and a noise estimation circuit, and wherein at least one of said MAGC circuits include; a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output; a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude; a noise estimation circuit for obtaining an estimate of noise; and a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude; an output transducer responsive to said plurality of MAGC circuits, wherein an acoustic signal having approximately a constant amplitude for a period of a predetermined amount of time is attenuated through interaction of said hearing compensation circuit and said noise estimation circuit.
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44. An audio output device, comprising:
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an input transducer for converting input acoustical energy into output electrical signals corresponding to the input acoustical energy; a plurality of audio bandpass filters coupled to receive said electrical signals, each of said audio bandpass filters having an output; a plurality of multiplicative automatic gain control (MAGC) circuits, each having at least one input and at least one output, an input of each of said MAGC circuits coupled to an output of one of said plurality of audio bandpass filters, at least one of said MAGC circuits including a hearing compensation circuit and a noise suppression circuit, and wherein at least one of said MAGC circuits include; a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output; a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude; a noise estimation circuit for obtaining an estimate of noise; and a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude; an output transducer responsive to said plurality of MAGC circuits, wherein an acoustic signal having approximately a constant amplitude for a period of a predetermined amount of time is attenuated through interaction of said hearing compensation circuit and said noise suppression circuit. - View Dependent Claims (45)
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46. An audio output device comprising:
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an input transducer for converting input acoustical energy into output electrical energy corresponding to the input acoustical energy; a plurality of audio bandpass filters coupled to the output of said input transducer; a plurality of multiplicative automatic gain control (MAGC) circuits, each having at least one input and at least one output, an input of each of said MAGC circuits coupled to an output of one of said audio bandpass filters, at least one of said MAGC circuits including a hearing compensation circuit and a noise estimation circuit, and wherein at least one of said MAGC circuits include; a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output; a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude; a noise estimation circuit for obtaining an estimate of noise; and a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude; an output transducer responsive to said plurality of MAGC circuits, wherein noise present in the acoustical energy is attenuated through interaction of said hearing compensation circuit and said noise estimation circuit. - View Dependent Claims (47, 48)
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49. An audio output device comprising:
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an input transducer for converting input acoustical energy into output electrical signals corresponding to the input acoustical energy; a plurality of audio bandpass filters coupled to the output of said input transducer; a plurality of multiplicative automatic gain control (MAGC) circuits, each having at least one input and at least one output, an input of each of said MAGC circuits coupled to an output of one of said audio bandpass filters, at least one of said MAGC circuits including a hearing compensation circuit and a noise estimation circuit, and wherein at least one of said MAGC circuits include; a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output; a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude; a noise estimation circuit for obtaining an estimate of noise; and a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude; an output transducer responsive to said plurality of MAGC circuits, wherein an acoustic signal having approximately a constant amplitude for a period of a predetermined amount of time is attenuated through interaction of said hearing compensation circuit and said noise estimation circuit. - View Dependent Claims (50, 51, 52, 53, 54, 55, 56)
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57. A hearing aid device, comprising:
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an input transducer for converting input acoustical energy into output electrical signals corresponding to the input acoustical energy; a plurality of audio bandpass filters coupled to receive said electrical signals, each of said audio bandpass filters having an output; a plurality of multiplicative automatic gain control (MAGC) circuits, each having at least one input and at least one output, an input of each of said MAGC circuits coupled to an output of one of said plurality of audio bandpass filters, at least one of said MAGC circuits including a hearing compensation circuit and a noise suppression circuit, and wherein at least one of said MAGC circuits include; a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output; a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude; a noise estimation circuit for obtaining an estimate of noise; and a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude; an output transducer responsive to said plurality of MAGC circuits, wherein an acoustic signal having approximately a constant amplitude for a period of a predetermined amount of time is attenuated through interaction of said hearing compensation circuit and said noise suppression circuit. - View Dependent Claims (58)
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59. An hearing aid device comprising:
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an input transducer for converting input acoustical energy into output electrical energy corresponding to the input acoustical energy; a plurality of audio bandpass filters coupled to the output of said input transducer; a plurality of multiplicative automatic gain control (MAGC) circuits, each having at least one input and at least one output, an input of each of said MAGC circuits coupled to an output of one of said audio bandpass filters, at least one of said MAGC circuits including a hearing compensation circuit and a noise estimation circuit, and wherein at least one of said MAGC circuits include; a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output; a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude; a noise estimation circuit for obtaining an estimate of noise; and a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude; an output transducer responsive to said plurality of MAGC circuits, wherein noise present in the acoustical energy is attenuated through interaction of said hearing compensation circuit and said noise estimation circuit. - View Dependent Claims (60)
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61. A hearing aid device, comprising:
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an input transducer for converting input acoustical energy into output electrical signals corresponding to the input acoustical energy; a plurality of audio bandpass filters coupled to the output of said input transducer; a plurality of multiplicative automatic gain control (MAGC) circuits, each having at least one input and at least one output, an input of each of said MAGC circuits coupled to an output of one of said audio bandpass filters, at least one of said MAGC circuits including a hearing compensation circuit and a noise estimation circuit, and wherein at least one of said MAGC circuits include; a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output; a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude; a noise estimation circuit for obtaining an estimate of noise; and a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude; an output transducer responsive to said plurality of multiplicative AGC circuits, wherein an acoustic signal having approximately a constant amplitude for a period of a predetermined amount of time is attenuated through interaction of said hearing compensation circuit and said noise estimation circuit. - View Dependent Claims (62, 63, 64, 65, 66, 67, 68)
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Specification