Apparatus and methods for vocal tract analysis of speech signals

• US 20060190257A1
• Filed: 03/15/2004
• Published: 08/24/2006
• Est. Priority Date: 03/14/2003
• Status: Abandoned Application

• Current Assignee: King's College London
• Original Assignee: King's College London
• Inventors: Pike, Edward Roy, Forbes, Barbara Janey
• Application Number:
  US10/548,844
• Publication Number:
  US 20060190257A1
• Time in Patent Office: Days
• US Class Current: 704/255
• CPC Class Codes: G10L 15/02 Feature extraction for speech recognition; Selection of recognition unit
• CPC Class Codes: G10L 2015/025 Phonemes, fenemes or fenones being the recognition units

Abstract

The present invention provides for speech processing apparatus arranged for the input or output of a speech data signal and including a function generating means arranged for producing a representation of a vocal-tract potential function representative of a speech source and as an example, a speaker identification process can comprise means to capture an incoming voice signal, for example from a microphone or telephone line; means to process the signal electronically to generate a time varying series of binary vocal-tract potentials and associated non-vowel binary parameters; means to refine the signal to revoke the speaker-independent speech components; and means to compare the residual signal with a database of such residual features of known individuals.

Claims

1-51. -51. (canceled)

52. Speech processing apparatus arranged for the input or output of a speech data signal and including a function generating means arranged for producing a representation of a vocal-tract six bit potential function for vowel identification representative of a speech source.

53. An apparatus as claimed in claim 52, and including means for deriving single-bit consonantal features.

54. An apparatus as claimed in claim 53, wherein consonantal sounds are defined as five or six additional bits.

55. As apparatus as claimed in claim 52, and arranged for deriving linguistic parameters representing sonorant sounds from the said 6-bits.

56. An apparatus as claimed in claim 55, wherein the sonorant sounds comprise one or more of nasalised vowels, laterals and rhotics.

57. An apparatus as claimed in claim 55, and arranged to include a further binary parameter with the said 6-bits serving to indicate the absence of periodic voicing at the glottis and/or the presence of aperiodic energy.

58. An apparatus as claimed in claim 55, wherein linguistic parameters in the order of two or three additional bits are defined for consonant sounds.

59. An apparatus as claimed in claim 52, and including means for specifying the said potential function as a general function having parameters serving to discriminate between phonemes.

60. An apparatus as claimed in claim 52, wherein the said function generating means is arranged to perform an inversion algorithm derived from a Green'"'"'s function solution for a vocal-tract wave function.

61. An apparatus as claimed in claim 52, wherein the said function generating means is arranged to produce potential function strings.

62. An apparatus as claimed in claim 52, and including means for discriminating between speaker dependent and speaker independent parts of the potential function.

63. Speech recognition apparatus including means for receiving a speech data signal and speech processing apparatus as claimed in claim 52, and further including means for conducting a template matching procedure on the output of the function generating means.

64. An apparatus as claimed in claim 63, and including means for performing an inversion calculation on the said speech data signal so as to derive the potential function.

65. An apparatus as claimed in claim 63, wherein the said template matching procedure is arranged to be conducted on a speaker independent part of the potential function.

66. An apparatus as claimed in claim 63, wherein the said means for conducting the template matching procedure is arranged to provide comparison to binary potential function strings stored in look-up tables, and which serves to achieve vocal-tract length normalization.

67. An apparatus as claimed in claim 66, and including parsing means arranged to receive phoneme identifiers output from the template matching means.

68. Voice identification apparatus including means for receiving a data signal, and speech processing apparatus as claimed in claim 52.

69. An apparatus as claimed in claim 68, and including means for performing an inversion calculation on the said speech data signal so as to derive the potential function.

70. An apparatus as claimed in claim 69, and including means for performing a matching operation on stored data identifying individual and on the basis of speaker-dependent parts of the potential function.

71. Speech synthesis apparatus including speech processing apparatus of claim 52, and including means for receiving speech parameters and for reconstructing a speech sound wave on the basis of the said potential function which serves to produce a speech token stream.

72. An apparatus as claimed in claim 71, and arranged such that the speech sound wave is reconstructed having regard to speaker-independent parts of the potential function.

73. An apparatus as claimed in claim 71, and including means for converting a stream of speech tokens into an analogue speech signal.

74. Speech signal compression apparatus including means for receiving a speech data signal, and speech processing apparatus as claimed in claim 52.

75. An apparatus as claimed in claim 74, and including means for performing an inversion calculation on the speech data signals so as to derive the potential function.

76. An apparatus as claimed in claim 74, and including template matching means for receiving the output from the function generating means and for reconstructing speaker independent parts of the potential function as compressed speech data.

77. An apparatus as claimed in 52, wherein the said function generating means is arranged to generate a time varying series of binary vocal-tract potentials and associated non-vowel binary parameters.

78. A speech processing method for processing input or output speech data and including the step of generating a representation of a vocal-tract six bit potential function for vowel identification representative of a speech source.

79. A method as claimed in claim 78, and including the step of specifying the said potential function as a general function having parameters serving to discriminate between phonemes.

80. A method as claimed in claim 78, and including the step of deriving single-bit consonantal features.

81. A method as claimed in claim 78, and including the definition of consonantal sounds as five or six additional bits.

82. A method as claimed in claim 78, and including the step of deriving linguistic parameters representing sonorant sounds for the said 6-bits.

83. A method as claimed in claim 80, wherein the sonorant sounds comprise one ore more of nasalised vowels, laterals and rhotics.

84. A method as claimed in claim 80, and including the step of including a further binary parameter with the said 6-bits serving to indicate the absence of periodic voicing at the glottis and/or the presence of aperiodic energy.

85. A method as claimed in claim 82, wherein linguistic parameters in the order of two or three additional bits are defined for consonant sounds.

86. A method as claimed in claim 78, and including the step of performing an inversion algorithm derived from a Green'"'"'s function solution for the vocal-tract wave function.

87. A method as claimed in claim 78, and including the step of producing the vocal-tract potential function as potential function strings.

88. A method as claimed in claim 78, and including the step of discriminating between speaker-dependent, and speaker-independent, parts of the potential function.

89. A speech recognition method including the step of receiving a speech data signal and further including the processing steps of claim 78 and also the step of conducting a template matching procedure on the vocal-tract potential function.

90. A method as claimed in claim 89, and including the step of performing an inversion calculation on the speech data signal so as to derive the potential function.

91. A method as claimed in claim 89, wherein the template matching procedure is conducted on a speaker-independent part of the potential function.

92. A method as claimed in claim 89, wherein the step of conducting the template matching procedure includes the step of providing a comparison with binary potential function strings stored in look-up tables.

93. A method as claimed in claim 92, and including the step of parsing received phoneme identifiers resulting from the template-matching step.

94. A voice identification method including the step of receiving a speech data signal and including speech-processing steps such as defined in claim 78.

95. A method as claimed in claim 94, and including the step of specifying the said potential function as a general function having parameters serving to discriminate between phonemes.

96. A method as claimed in claim 95, and including the step of performing a matching operation on the stored data identifying individuals, and on the basis of speaker-dependent parts of the potential function.

97. A speech synthesis method including the processing steps of claim 78, and further including the step of receiving speech parameters and for reconstructing a speech sound wave on the basis of the said potential function.

98. A method as claimed in claim 97, and including the step of reconstructing the speech sound wave having regard to speaker-independent parts of the potential function.

99. A method as claimed in claim 97, and including the step of converting a stream of speech tokens into an analogue speech signal.

100. A speech signal compression method, including the steps of receiving a speech data signal and further including the speech processing steps of claim 78.

101. A method as claimed in claim 100, and including the step of performing an inversion calculation on the speech data signals so as to derive the potential function.

102. A method as claimed in claim 100, and including the step of receiving the result of the potential function and for delivering the same to template matching means and for reconstructing speaker-independent parts of the potential function as compressed speech data.