Speech privacy system and/or associated method

• US 10,726,855 B2
• Filed: 03/15/2017
• Issued: 07/28/2020
• Est. Priority Date: 03/15/2017
• Status: Active Grant

• Current Assignee: Guardian Glass LLC (KOCH Industries Incorporated)
• Original Assignee: Guardian Glass LLC (KOCH Industries Incorporated)
• Inventors: Krasnov, Alexey
• Primary Examiner(s): Shin, Seong-Ah A
• Application Number:
  US15/459,220
• Publication Number:
  US 20180268834A1
• Time in Patent Office: 1,231 Days
• CPC Class Codes: G10K 11/175 using interference effects; Masking sound
• CPC Class Codes: G10K 11/1754 Speech masking
• CPC Class Codes: G10L 21/003 Changing voice quality, e.g. pitch or formants
• CPC Class Codes: G10L 21/16 Transforming into a non-visible representation devices or methods enabling ear patients to replace direct auditory perception by another kind of perception A61F11/04
• CPC Class Codes: G10L 25/48 specially adapted for particular use
• CPC Class Codes: H04K 2203/12 for acoustic communication
• CPC Class Codes: H04K 3/41 characterized by the control of the jamming activation or deactivation time control of jamming activation and deactivation time only for the purpose of alternating between jamming mode and target monitoring mode H04K3/45
• CPC Class Codes: H04K 3/45 characterized by including monitoring of the target or target signal, e.g. in reactive jammers or follower jammers for example by means of an alternation of jamming phases and monitoring phases, called "look-through mode"
• CPC Class Codes: H04K 3/46 characterized in that the jamming signal is produced by retransmitting a received signal, after delay or processing
• CPC Class Codes: H04K 3/825 by jamming
• CPC Class Codes: H04K 3/84 related to preventing electromagnetic interference in petrol station, hospital, plane or cinema

Abstract

Certain example embodiments relate to speech privacy systems and/or associated methods. The techniques described herein disrupt the intelligibility of the perceived speech by, for example, superimposing onto an original speech signal a masking replica of the original speech signal in which portions of it are smeared by a time delay and/or amplitude adjustment, with the time delays and/or amplitude adjustments oscillating over time. In certain example embodiments, smearing of the original signal may be generated in frequency ranges corresponding to formants, consonant sounds, phonemes, and/or other related or non-related information-carrying building blocks of speech. Additionally, or in the alternative, annoying reverberations particular to a room or area in low frequency ranges may be “cut out” of the replica signal, without increasing or substantially increasing perceived loudness.

Claims

1. A method for disrupting speech intelligibility, the method comprising:

receiving, via a microphone, an original speech signal corresponding to original speech;

generating an intelligibility-disrupting masking signal comprising smeared cues of the original speech in the original speech signal; and

reducing the level of intelligibility of the original speech signal by outputting, through a speaker, the intelligibility-disrupting masking signal comprising the smeared speech cues,

wherein the intelligibility-disrupting masking signal is time delayed relative to the original speech signal,

wherein the intelligibility-disrupting masking signal is generated such that the amplitude of the intelligibility-disrupting masking signal is modulated in time, and

wherein the time delay oscillates in time.

2. The method of claim 1, wherein the intelligibility-disrupting masking signal is time-delayed by 20-150 ms.

3. The method of claim 1, wherein the intelligibility-disrupting masking signal is time-delayed by 80 ms.

4. The method of claim 1, wherein the time delay oscillates in time in relation to the original signal within a range of 80-230 ms.

5. The method of claim 4, further comprising generating the intelligibility-disrupting masking signal such that gain corresponding to the intelligibility-disrupting masking signal added to the original speech signal is 0.05-0.25%.

6. The method of claim 1, wherein the time delay oscillates with an oscillation frequency of 1-10 Hz.

7. The method of claim 6, wherein the time delay oscillates with an oscillation frequency of 2-6 Hz.

8. The method of claim 1, wherein smeared cues are generated at a frequency of 0.01-20 Hz.

9. The method of claim 8, wherein smeared cues are generated at a frequency of 2-6 Hz.

10. The method of claim 1, further comprising outputting, through the speaker, the intelligibility-disrupting masking signal together with a prerecorded mix of multiple voices.

11. The method of claim 10, wherein the prerecorded mix of multiple voices comprises 2-7 different voices.

12. The method of claim 10, wherein the prerecorded mix of multiple voices comprises 3 different voices.

13. A speech intelligibility disrupting device, comprising:

control circuitry configured to;

receive, from a microphone, an original speech signal corresponding to original speech;

generate an intelligibility-disrupting masking signal comprising smeared cues of the original speech in the original speech signal, the cues being smeared through control circuitry induced reverberation of the original speech signal; and

cause a speaker to output the intelligibility-disrupting masking signal comprising the smeared speech cues to reduce the level of intelligibility of the original speech signal,

wherein the intelligibility-disrupting masking signal is time delayed relative to the original speech signal, and

wherein the intelligibility-disrupting masking signal is generated such that the amplitude of the intelligibility-disrupting masking signal is modulated in time.

14. The device of claim 13, wherein the intelligibility-disrupting masking signal is time-delayed by 20-150 ms.

15. The device of claim 13, wherein the time delay oscillates in time.

16. The device of claim 15, wherein the time delay oscillates in time in relation to the original signal within a range of 80-230 ms.

17. The device of claim 16, wherein the intelligibility-disrupting masking signal is generated such that gain corresponding to the intelligibility-disrupting masking signal added to the original speech signal is 0.05-0.25%.

18. The device of claim 15, wherein the time delay oscillates with an oscillation frequency of 1-10 Hz.

19. The device of claim 13, wherein smeared cues are generated at a frequency of 2-6 Hz.

20. The device of claim 13, further comprising outputting, through the speaker, the intelligibility-disrupting masking signal together with a prerecorded mix of multiple voices.

21. The speech intelligibility disrupting device of claim 13, wherein the reverberation includes temporal phasing and amplitude modulation of the target signal.

22. The speech intelligibility disrupting device of claim 13, wherein the control circuitry is voice-activated, and wherein the control circuitry is configured to automatically adjusts to psycholinguistic aspects and acoustic-phonetic cues of the original speech in generating the intelligibility-disrupting masking signal.

23. The speech intelligibility disrupting device of claim 13, wherein the reverberation is generated to disrupt the rhythm of the original speech, mask acoustic cues of overlapping syllables and vowels, and/or eliminate artificially created infra-sound with sub-threshold frequencies that resonate adversely with the brain waves.

24. The speech intelligibility disrupting device of claim 13, wherein output of the intelligibility-disrupting masking signal causes the original speech signal to be perceivable as an unintelligible foreign language.

25. A speech intelligibility disrupting system, comprising:

a microphone;

a speaker; and

control circuitry configured to;

receive, from the microphone, an original speech signal corresponding to original speech;

generate an intelligibility-disrupting masking signal comprising smeared cues of the original speech in the original speech signal; and

cause the speaker to output the intelligibility-disrupting masking signal comprising the smeared speech cues to reduce the level of intelligibility of the original speech signal,

wherein the intelligibility-disrupting masking signal is time delayed relative to the original speech signal, the time delay oscillating in time, and

wherein the intelligibility-disrupting masking signal is generated such that the amplitude of the intelligibility-disrupting masking signal oscillates in time.

26. An acoustic wall, comprising the system of claim 25.