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Showing papers on "Noise published in 2012"


Journal ArticleDOI
TL;DR: The audio inpainting framework that recovers portions of audio data distorted due to impairments such as impulsive noise, clipping, and packet loss is proposed and this approach is shown to outperform state-of-the-art and commercially available methods for audio declipping in terms of Signal-to-Noise Ratio.
Abstract: We propose the audio inpainting framework that recovers portions of audio data distorted due to impairments such as impulsive noise, clipping, and packet loss. In this framework, the distorted data are treated as missing and their location is assumed to be known. The signal is decomposed into overlapping time-domain frames and the restoration problem is then formulated as an inverse problem per audio frame. Sparse representation modeling is employed per frame, and each inverse problem is solved using the Orthogonal Matching Pursuit algorithm together with a discrete cosine or a Gabor dictionary. The Signal-to-Noise Ratio performance of this algorithm is shown to be comparable or better than state-of-the-art methods when blocks of samples of variable durations are missing. We also demonstrate that the size of the block of missing samples, rather than the overall number of missing samples, is a crucial parameter for high quality signal restoration. We further introduce a constrained Matching Pursuit approach for the special case of audio declipping that exploits the sign pattern of clipped audio samples and their maximal absolute value, as well as allowing the user to specify the maximum amplitude of the signal. This approach is shown to outperform state-of-the-art and commercially available methods for audio declipping in terms of Signal-to-Noise Ratio.

229 citations


Journal ArticleDOI
TL;DR: To the knowledge, this is the first evidence that insects from noisy habitats produce different acoustic signals than conspecifics from quiet habitats, possibly using a more permanent mechanism for signal adjustment than behavioural plasticity, which was found in different bird species adjusting to high background noise levels.
Abstract: Summary 1. Anthropogenic noise is known to affect acoustic signal production in birds, frogs and mammals. These animals use different mechanisms to adjust their signals to elevated background noise levels (increase in signal amplitude, shift to higher frequencies, etc.). Previous studies have concentrated on behaviourally plastic changes in signal production as a result of elevated background noise levels. To our knowledge, long-term effects of anthropogenic noise on signal production have not yet been investigated. Moreover, strategies of invertebrate species to ensure acoustic signal transmission under anthropogenic noise have not been examined, so far. 2. We tested whether and how male Chorthippus biguttulus grasshoppers from noisy roadside habitats may adjust acoustic courtship signals to elevated background noise levels, compared with conspecifics from quiet control habitats. In this species, sexually selected male courtship signals serve to attract potential mating partners, which make the undisturbed transmission of signals in habitats with increased background noise levels crucial for male reproductive success. 3. Compared to males from control populations, males from roadside habitats produced songs with a significantly higher local frequency maximum under standardized, quiet recording conditions. This local frequency maximum (in the range of c .6 –9 kHz) overlaps with low-frequent road noise that has the potential to degrade or mask this part of the signals’ frequency spectrum. 4. To our knowledge, this is the first evidence that insects from noisy habitats produce different acoustic signals than conspecifics from quiet habitats, possibly using a more permanent mechanism for signal adjustment than behavioural plasticity, which was found in different bird species adjusting to high background noise levels. Such an effect of anthropogenic noise has not been shown for any invertebrate species before, and our results suggest that similar strategies to avoid degradation or masking by noise (i.e. increase in carrier frequency) are used over a wide range of taxa, including both, vertebrates and invertebrates.

104 citations


Journal ArticleDOI
TL;DR: This is the first study to investigate how noise and urban development affect song frequency characteristics of multiple bird species, and found that minimum song frequency increased as noise level increased for 2 of 6 species, with 5 of6 species showing a strong trend in the predicted direction.
Abstract: Many avian species live, breed, and communicate in urban areas. To survive and reproduce in these areas, birds must transmit their signals to intended receivers. As an arena for acoustic communication, 2 salient features of the urban environment are an abundance of reflective surfaces and a high level of low-frequency anthropogenic noise. Each presents unique communication challenges, with hard surfaces reflecting and distorting high frequencies and noise masking low-frequency song components. Based on this, we predicted that noise level would affect minimum song frequency and urban development (percentage of impervious surface) would affect maximum frequency and frequency range. We compared the effects of urban development and noise on songs of 6 bird species at 28 sites along an urban to rural gradient, across a broad range of noise levels. We found that minimum song frequency increased as noise level increased for 2 of 6 species, with 5 of 6 species showing a strong trend in the predicted direction. Species with lower frequency songs were more affected by noise. Maximum frequency and frequency range decreased for 2 of 6 species as urban development increased, and this effect was stronger for species with higher frequency songs. For some species, minimum frequency only increased with noise at less urban sites and similarly, maximum frequency and frequency range only decreased with urbanization at quiet sites, suggesting a trade-off between different vocal adjustments. Ours is the first study to investigate how noise and urban development affect song frequency characteristics of multiple bird species.

93 citations


Journal ArticleDOI
TL;DR: The relationship between pure-tone thresholds, the articulation index, and the ability to recognize speech in quiet and in noise is investigated to find a new classification scheme of hearing impairment based on the audiogram and the speech reception in noise thresholds, as measured with the HINT.
Abstract: Background Speech recognition in noise testing has been conducted at least since the 1940s (Dickson et al, 1946). The ability to recognize speech in noise is a distinct function of the auditory system (Plomp, 1978). According to Kochkin (2002), difficulty recognizing speech in noise is the primary complaint of hearing aid users. However, speech recognition in noise testing has not found widespread use in the field of audiology (Mueller, 2003; Strom, 2003; Tannenbaum and Rosenfeld, 1996). The audiogram has been used as the "gold standard" for hearing ability. However, the audiogram is a poor indicator of speech recognition in noise ability. Purpose This study investigates the relationship between pure-tone thresholds, the articulation index, and the ability to recognize speech in quiet and in noise. Research design Pure-tone thresholds were measured for audiometric frequencies 250-6000 Hz. Pure-tone threshold groups were created. These included a normal threshold group and slight, mild, severe, and profound high-frequency pure-tone threshold groups. Speech recognition thresholds in quiet and in noise were obtained using the Hearing in Noise Test (HINT) (Nilsson et al, 1994; Vermiglio, 2008). The articulation index was determined by using Pavlovic's method with pure-tone thresholds (Pavlovic, 1989, 1991). Study sample Two hundred seventy-eight participants were tested. All participants were native speakers of American English. Sixty-three of the original participants were removed in order to create groups of participants with normal low-frequency pure-tone thresholds and relatively symmetrical high-frequency pure-tone threshold groups. The final set of 215 participants had a mean age of 33 yr with a range of 17-59 yr. Data collection and analysis Pure-tone threshold data were collected using the Hughson-Weslake procedure. Speech recognition data were collected using a Windows-based HINT software system. Statistical analyses were conducted using descriptive, correlational, and multivariate analysis of covariance (MANCOVA) statistics. Results The MANCOVA analysis (where the effect of age was statistically removed) indicated that there were no significant differences in HINT performances between groups of participants with normal audiograms and those groups with slight, mild, moderate, or severe high-frequency hearing losses. With all of the data combined across groups, correlational analyses revealed significant correlations between pure-tone averages and speech recognition in quiet performance. Nonsignificant or significant but weak correlations were found between pure-tone averages and HINT thresholds. Conclusions The ability to recognize speech in steady-state noise cannot be predicted from the audiogram. A new classification scheme of hearing impairment based on the audiogram and the speech reception in noise thresholds, as measured with the HINT, may be useful for the characterization of the hearing ability in the global sense. This classification scheme is consistent with Plomp's two aspects of hearing ability (Plomp, 1978).

76 citations


Journal ArticleDOI
TL;DR: The Quiet Places Project in Amsterdam suggests that creating quiet places and enhancing possibilities for quiet recreation in urban environments can have a positive effect on the quality of life in the city.
Abstract: This paper describes the Quiet Places Project in Amsterdam. The purpose of the study was to find out: (1) which public quiet places there are according to Amsterdam residents; (2) what characterizes a quiet place; (3) to what extent do residents want peace and quiet; (4) how do residents realize these needs. The factors determining the need for quietness are presented in a model showing the influence of demographic and socio-economic issues, health status, sensitiveness to noise, daily activities and the noisiness in and around home. Most important of these factors is sensitivity to noise. Elderly and less healthy people are more often sensitive to noise. People who are annoyed by sound from traffic, airplanes and the like show a higher need for quietness. People with a lively household or neighbourhood report lower needs for quietness. Visiting a quiet place and going outside to walk or bike can have a compensating effect on the need for quietness. This suggests that creating quiet places and enhancing possibilities for quiet recreation in urban environments can have a positive effect on the quality of life in the city. Objective noise levels at the quiet places were taken from environmental noise maps. This shows that there may be a preference for low transportation noise levels, but levels up to 60 dB Lday are acceptable. Apparently this depends on a relative quietness or on non-acoustic characteristics of an area: the presence of vegetation and other pleasant stimuli.

73 citations


Journal ArticleDOI
TL;DR: The inclusion of a voice activity detector in the weighting scheme improves speech recognition over different system architectures and confidence measures, leading to an increase in performance more relevant than any difference between the proposed confidence measures.
Abstract: The integration of audio and visual information improves speech recognition performance, specially in the presence of noise. In these circumstances it is necessary to introduce audio and visual weights to control the contribution of each modality to the recognition task. We present a method to set the value of the weights associated to each stream according to their reliability for speech recognition, allowing them to change with time and adapt to different noise and working conditions. Our dynamic weights are derived from several measures of the stream reliability, some specific to speech processing and others inherent to any classification task, and take into account the special role of silence detection in the definition of audio and visual weights. In this paper, we propose a new confidence measure, compare it to existing ones, and point out the importance of the correct detection of silence utterances in the definition of the weighting system. Experimental results support our main contribution: the inclusion of a voice activity detector in the weighting scheme improves speech recognition over different system architectures and confidence measures, leading to an increase in performance more relevant than any difference between the proposed confidence measures.

71 citations


Journal ArticleDOI
TL;DR: The quiet side effect seems to be especially applicable for noise sensitive persons, and a bedroom located at the quiet side leads to an even stronger reduction of the self-reported noise annoyance.
Abstract: This study provides additional evidence for the positive effect of the presence of a quiet facade at a dwelling and aims at unraveling potential mechanisms. Locations with dominant road traffic noise and high Lden-levels at the most exposed facade were selected. Dwellings both with and without a quiet facade were deliberately sought out. Face-to-face questionnaires (N = 100) were taken to study the influence of the presence of a quiet side in relation to noise annoyance and sleep disturbance. As a direct effect, the absence of a quiet facade in the dwelling (approached as a front-back facade noise level difference smaller than 10 dBA) leads to an important increase of at least moderately annoyed people (odds-ratio adjusted for noise sensitivity equals 3.3). In an indirect way, a bedroom located at the quiet side leads to an even stronger reduction of the self-reported noise annoyance (odds-ratio equal to 10.6 when adjusted for noise sensitivity and front facade Lden). The quiet side effect seems to be especially applicable for noise sensitive persons. A bedroom located at the quiet side also reduces noise-induced sleep disturbances. On a loud side, bedroom windows are more often closed, however, conflicting with the preference of dwellers.

66 citations


Patent
12 Apr 2012
TL;DR: In this paper, the subband gain control using information from a noise reference is proposed to enhance audio quality in a noisy environment, based on sub-band gain controlling using information of the noise reference.
Abstract: Enhancement of audio quality (e.g., speech intelligibility) in a noisy environment, based on subband gain control using information from a noise reference, is described.

62 citations


Proceedings ArticleDOI
25 Mar 2012
TL;DR: This paper proposes an effective splicing detection method for audios by detecting abnormal differences in the local noise levels in an audio signal and demonstrates the efficacy and robustness of the proposed method using both synthetic and realistic audio splicing forgeries.
Abstract: One common form of tampering in digital audio signals is known as splicing, where sections from one audio is inserted to another audio. In this paper, we propose an effective splicing detection method for audios. Our method achieves this by detecting abnormal differences in the local noise levels in an audio signal. This estimation of local noise levels is based on an observed property of audio signals that they tend to have kurtosis close to a constant in the band-pass filtered domain. We demonstrate the efficacy and robustness of the proposed method using both synthetic and realistic audio splicing forgeries.

61 citations


Proceedings ArticleDOI
25 Mar 2012
TL;DR: This paper develops a technique for detecting signature audio events, that is based on identifying patterns of occurrences of automatically learned atomic units of sound, which it is called Acoustic Unit Descriptors or AUDs.
Abstract: In most real-world audio recordings, we encounter several types of audio events. In this paper, we develop a technique for detecting signature audio events, that is based on identifying patterns of occurrences of automatically learned atomic units of sound, which we call Acoustic Unit Descriptors or AUDs. Experiments show that the methodology works as well for detection of individual events and their boundaries in complex recordings.

58 citations


Patent
Nitin Kwatra1
24 May 2012
TL;DR: In this article, a secondary path estimating adaptive filter is used to estimate the electro- acoustical path from the noise canceling circuit through the transducer so that source audio can be removed from the error signal.
Abstract: A personal audio device, such as a wireless telephone, includes an adaptive noise canceling (ANC) circuit that adaptively generates an anti-noise signal from a reference microphone signal and injects the anti-noise signal into the speaker or other transducer output to cause cancellation of ambient audio sounds. An error microphone is also provided proximate the speaker to provide an error signal indicative of the effectiveness of the noise cancellation. A secondary path estimating adaptive filter is used to estimate the electro- acoustical path from the noise canceling circuit through the transducer so that source audio can be removed from the error signal. Noise is injected either continuously and inaudibly below the source audio, or in response to detection that the source audio is low in amplitude, so that the adaptation of the secondary path estimating adaptive filter can be maintained, irrespective of the presence and amplitude of the source audio.

Journal ArticleDOI
Junhong Zhou1, Dongdong Liu1, Xin Li1, Jing Ma1, Jue Zhang1, Jing Fang1 
TL;DR: It is demonstrated that steady pink noise has significant effect on reducing brain wave complexity and inducing more stable sleep time to improve sleep quality of individuals.

Journal ArticleDOI
TL;DR: The results strongly suggest an active role for female birds in steering male song behaviour under noisy conditions, which is important to understand the mechanisms related to communication in noise and reveal the critical role of ecology in shaping animal interactions.
Abstract: Summary 1. Anthropogenic noise can affect intra-pair communication and therefore interfere with reproductive success. However, many animals have various signal strategies to cope with noise, although it is unclear whether they rely on direct auditory feedback from their own perception of noise or signal-to-noise level or on indirect social feedback from receivers. 2. We studied the role of social feedback on male great tit (Parus major) song adjustment by exclusively exposing females to artificial traffic noise inside their nest box. 3. We found a delay in female response latencies to male song in the noisy condition compared to the control condition on the first day of noise exposure. Males from the noise treatment group, not directly exposed to noise themselves, sang closer to the nest box within 3 days after the start of exposure. 4. The male's closer proximity to the nest box most likely led to the observed higher song amplitudes at the noisy nest boxes compared to quiet control nest boxes, and explains why the inside signal-to-noise ratios were restored to equal levels between treatment and control nest boxes after several days of exposure. 5. The initial difference between treatment groups in female response latencies at the start of exposure also disappeared accordingly. 6. Our results strongly suggest an active role for female birds in steering male song behaviour under noisy conditions. Males did not receive direct exposure during intra-pair communication, but adjusted their behaviour in the predicted direction. These data are important to understand the mechanisms related to communication in noise and reveal the critical role of ecology in shaping animal interactions.

Patent
09 May 2012
TL;DR: In this article, a self-adaptive voice endpoint detection method was proposed for automatic caption generating system, in particular to a selfadaptive VO detection method for continuous voice under the condition that the background noise is changed frequently so as to improve the VO endpoint detection efficiency under a complex noise background.
Abstract: The invention relates to voice detection technology in an automatic caption generating system, in particular to a self-adaptive voice endpoint detection method The method comprises the following steps: dividing an audio sampling sequence into frames with fixed lengths, and forming a frame sequence; extracting three audio characteristic parameters comprising short-time energy, short-time zero-crossing rate and short-time information entropy aiming at data of each frame; calculating short-time energy frequency values of the data of each frame according to the audio characteristic parameters, and forming a short-time energy frequency value sequence; analyzing the short-time energy frequency value sequence from the data of the first frame, and seeking for a pair of voice starting point and ending point; analyzing background noise, and if the background noise is changed, recalculating the audio characteristic parameters of the background noise, and updating the short-time energy frequencyvalue sequence; and repeating the processes till the detection is finished The method can carry out voice endpoint detection for the continuous voice under the condition that the background noise ischanged frequently so as to improve the voice endpoint detection efficiency under a complex noise background

Journal ArticleDOI
TL;DR: The results of the study suggest that the N nucleus 5 sound processor provides significantly better speech recognition in quiet and in noise when compared with performance with the Nucleus Freedom processor.
Abstract: Objective Previous research shows that cochlear implant users experience significant difficulty with speech perception in noisy listening situations. There is a paucity of research evaluating the potential improvement in speech recognition in noise provided by a dual-microphone directional system in a commercial implant sound processor. The primary objective of this study was to compare speech recognition in quiet and in noise for the Nucleus Freedom and Nucleus 5 CP810 sound processors set to the manufacturer's default user programs for quiet and noisy environments. Research design Crossover with repeated-measures design. Setting This multi-center study was conducted across four cochlear implant clinics in the United States. Patients Thirty-five adults with unilateral Nucleus Freedom cochlear implants. All subjects had used their cochlear implant for at least 6 months and had substantial open-set word recognition as evidenced by a score of at least 40% correct on the Consonant-Nucleus-Consonant (CNC) monosyllabic word recognition test in quiet. Intervention All subjects (previous users of the Nucleus Freedom sound processor) were fitted with the Nucleus 5 sound processor. Performance was assessed while these subjects used each sound processor in the default user program the manufacturer recommends for quiet and noisy conditions. Main outcome measures Speech recognition was assessed with CNC monosyllabic words in quiet and sentences in noise from the BKB-SIN (Bamford-Kowal-Bench Sentences in Noise) test. The data were analyzed with descriptive statistics and performance with each processor in each listening condition was compared using a repeated-measures analysis of variance. Results Word recognition in quiet was significantly better with the Nucleus 5 sound processor when compared to performance with the Nucleus Freedom processor. In noise, the Nucleus 5 sound processor also provided a significant improvement in speech recognition relative to the performance with the Nucleus Freedom. Conclusion The results of the study suggest that the Nucleus 5 sound processor provides significantly better speech recognition in quiet and in noise when compared with performance with the Nucleus Freedom processor.

PatentDOI
Jeffrey J. Terlizzi1
TL;DR: In this article, the authors proposed a method for noise cancellation and power management in a wireless headset using two or more omni-directional microphones to generate a noise canceling cone.
Abstract: This includes systems and methods for noise cancellation and power management in a wireless headset. The wireless headset can perform noise cancellation by using two or more omni-directional microphones to generate a noise canceling “cone.” Audio signals received outside of the cone can be filtered out. An accelerometer can be used to determine the location of the wireless headset and the system can then properly position the cone to face the user's voice and filter out other audio signals. Additionally, by monitoring the ambient noise, the system can save power by turning off the noise cancellation system when the amount of ambient noise is below a threshold value.

Patent
14 Feb 2012
TL;DR: The spectral domain is efficiently used in order to parameterize the background noise thereby yielding a background noise synthesis which is more realistic and thus leads to a more transparent active to inactive phase switching as mentioned in this paper.
Abstract: The spectral domain is efficiently used in order to parameterize the background noise thereby yielding a background noise synthesis which is more realistic and thus leads to a more transparent active to inactive phase switching.


Journal ArticleDOI
TL;DR: The findings indicate that the preschool sound environment is hazardous regarding auditory disorders and the dB(A) level and fluctuation of the noise exposure were significantly correlated to the number of children per department.
Abstract: Hearing impairments and tinnitus are being reported in an increasing extent from employees in the preschool. The investigation included 101 employees at 17 preschools in Umea county, Sweden. Individual noise recordings and stationary recordings in dining rooms and play halls were conducted at two departments per preschool. The effects of noise exposures were carried out through audiometric screenings and by use of questionnaires. The average individual noise exposure was close to 71 dB(A), with individual differences but small differences between the preschools. The noise levels in the dining room and playing halls were about 64 dB(A), with small differences between the investigated types of rooms and preschools. The hearing loss of the employees was significantly higher for the frequencies tested when compared with an unexposed control group in Sweden. Symptoms of tinnitus were reported among about 31% of the employees. Annoyance was rated as somewhat to very annoying. The voices of the children were the most annoying noise source. The dB(A) level and fluctuation of the noise exposure were significantly correlated to the number of children per department. The preschool sound environment is complex and our findings indicate that the sound environment is hazardous regarding auditory disorders. The fluctuation of the noise is of special interest for further research.

01 Jan 2012
TL;DR: 42 distinct labels, the “noisemes”, developed for the manual annotation of noise segments as they occur in audio streams of consumer captured and semiprofessionally produced videos are introduced.
Abstract: Audio information retrieval is a difficult problem due to the highly unstructured nature of the data. A general labeling system for identifying audio patterns could unite research efforts in the field. This paper introduces 42 distinct labels, the “noisemes”, developed for the manual annotation of noise segments as they occur in audio streams of consumer captured and semiprofessionally produced videos. The labels describe distinct noise units based on audio concepts, independent of visual concepts as much as possible. We trained a recognition system using 5.6 hours of manually labeled data, and present recognition results.

Journal ArticleDOI
TL;DR: The OlKiSa is a valid audiometric test to quantify speech perception in quiet in children from age 4 to 10 years, and age-specific standards for 50% speech Perception in quiet (speech reception threshold, SRT) are provided.
Abstract: Objective: To assess speech perception in children, speech audiometric sentence tests are generally better suited than single word tests because of their steeper discrimination function and thus higher sensitivity. A disadvantage of older German single word speech audiometric tests for children is their inapplicability in quiet and in noise. Moreover, their discrimination functions are shallower than those of optimized sentence tests, particularly in noise. The Oldenburg sentence test for children (Oldenburger Kinder-Satztest; OlKiSa) has already been shown to test reliably the speech perception in noise in normal-hearing children. Testing hearing-impaired children in noise, however, may be difficult. Therefore, quality criteria and norms for testing in quiet are also needed. Study sample: The OlKiSa in quiet was validated with 224 normal-hearing children between ages 4 to 10 years. Results: The discrimination functions are steeper (6.4 to 10.7 %/dB) than those of the commonly used German single w...

Patent
21 Feb 2012
TL;DR: In this paper, a wearable accoutrement such as a wristwatch records noises within a wearer's vicinity, and white noises may be filtered out to output pure human voices, which can be activated manually or automatically during a "panic mode" as indicated by a loud noise or sudden biological changes such as an increase in heart rate or body temperature.
Abstract: A wearable accoutrement such as a wristwatch records noises within a wearer's vicinity, and white noises may be filtered out to output pure human voices. The voice recording feature can be activated manually or automatically during a “panic mode” as indicated by a loud noise or sudden biological changes such as an increase in heart rate or body temperature. The accoutrement can also monitor other environmental elements such as light, motion and audio and may be paired with a wireless phone such that noise from a stressful event can be sent to a remote server which processes the data. A motion sensor in the accoutrement may also activate an audible alarm in the event of physical trauma to the wearer to induce an attacker to flee.

Patent
10 Jan 2012
TL;DR: In this article, the authors describe a communication system that includes a receiving path over which received speech signals traverse in an audio stream, and a dynamic audio enhancement device disposed in the receiving path.
Abstract: Various embodiments relate to signal processing and, more particularly, to processing of received speech signals to preserve and enhance speech intelligibility. In one embodiment, a communications apparatus includes a receiving path over which received speech signals traverse in an audio stream, and an dynamic audio enhancement device disposed in the receiving path. The dynamic audio enhancement ("DAE") device is configured to modify an amount of volume and an amount of equalization of the audio stream. The DAE device can include a noise level estimator ("NLE") configured to generate a signal representing a noise level estimate. The noise level estimator can include a non-stationary noise detector and a stationary noise detector. The noise level estimator can be configured to generate the signal representing a first noise level estimate based on detection of the non-stationary noise or a second noise level estimate based on detection of the stationary noise.

Proceedings ArticleDOI
01 Nov 2012
TL;DR: This paper presents an algorithm based on mean-quantization in Discrete Wavelet Transform (DWT) domain that improves systemic security and robustness against malicious attack, and maintains high audio quality and yields a high recovery rate after attacks by commonly used audio data manipulations.
Abstract: To enhance security and robustness of digital audio watermarking algorithms, this paper presents an algorithm based on mean-quantization in Discrete Wavelet Transform (DWT) domain. A binary image is used as a watermark, and is encrypted with chaotic encryption with secret key. This approach is based on the embedding of an encrypted watermark in the low frequency components using a two wavelet functions with adaptation to the frame size. The reason for embedding the watermark in the low frequency components is that these components' energy is high enough to embed the watermark in such a way that the watermark is inaudible; therefore, it should not alter the audible content and should not be easy to remove. The algorithm has a good security because only the authorized can detect the copyright information embedded to the host audio signal. The watermark can be blindly extracted without knowledge of the original signal. To evaluate the performance of the presented audio watermarking method, objective quality tests including bit error rate (BER), normalized cross correlation(NCC), peak-signal to noise ratio (PSNR) are conducted for the watermark and Signal-to-Noise Ratio(SNR) for audio signals. The tests' results show that the approach maintains high audio quality, and yields a high recovery rate after attacks by commonly used audio data manipulations such as noise addition, amplitude modification, low-pass filtering, re-quantization, re-sampling, cropping, cutting, and compression. Simulation results show that our approach not only makes sure robustness against common attacks, but it also further improves systemic security and robustness against malicious attack.

Patent
20 Nov 2012
TL;DR: In this paper, a method and apparatus that filters audio data received from a speaking person that includes a specific filter for that speaker is presented, where audio characteristics of the speaker's voice may be collected and the specific filter may be formed to reduce noise while also enhancing voice quality.
Abstract: A method and apparatus that filters audio data received from a speaking person that includes a specific filter for that speaker The audio characteristics of the speaker's voice may be collected and the specific filter may be formed to reduce noise while also enhancing voice quality For instance, if a speaker's voice does not contain specific frequencies, then a filter may cancel the noise at such frequencies to ease noise cancellation and reduce processing sound spectrum for cleaning that is not needed Additionally, the strength frequencies of a speaker's voice may be identified from the collected audio characteristics and those spectrums can be filtered with finer granularity to provide a speaker specific filter that enhances the voice quality of the speaker's voice data that is transmitted or output by a communication device The audio data may also be output based upon a user's predefined hearing spectrum

Journal ArticleDOI
01 Jul 2012
TL;DR: Investigation of habitat occupancy and signal change in response to noise in the Blue-gray Gnatcatcher and the Spotted Towhee found that species that alter the frequency of their vocalizations in responded to noise would use noisy and quiet areas similarly, and thatspecies that do not adjust their vocalization in responseto noise may avoid noisy areas.
Abstract: Several urban-adapted species sing at a higher frequency in noisy urban areas than in quiet locations. Yet it remains unclear whether the ability to adjust signals in response to noise is related to an ability to persist in noisy areas, because signal change and habitat use are infrequently measured within a single study. We investigated occupancy and signal change in response to noise in the Blue-gray Gnatcatcher (Polioptila caerulea) and the Spotted Towhee (Pipilo maculatus) using a study system that eliminates uncontrolled effects of habitat features that may influence song frequency or habitat use and controls for the negative effect of noise on bird surveys. We predicted that species that alter the frequency of their vocalizations in response to noise would use noisy and quiet areas similarly, and that species that do not adjust their vocalizations in response to noise may avoid noisy areas. Both study species were uninfluenced by noise in their habitat occupancy, but only Spotted Towhees sa...

Journal ArticleDOI
28 Nov 2012-PLOS ONE
TL;DR: The results indicate that the temporal and the spectral weighting of the loudness of a time-varying sound are independent processes, which are discussed in the context of current loudness models.
Abstract: Real-world sounds like speech or traffic noise typically exhibit spectro-temporal variability because the energy in different spectral regions evolves differently as a sound unfolds in time. However, it is currently not well understood how the energy in different spectral and temporal portions contributes to loudness. This study investigated how listeners weight different temporal and spectral components of a sound when judging its overall loudness. Spectral weights were measured for the combination of three loudness-matched narrowband noises with different center frequencies. To measure temporal weights, 1,020-ms stimuli were presented, which randomly changed in level every 100 ms. Temporal weights were measured for each narrowband noise separately, and for a broadband noise containing the combination of the three noise bands. Finally, spectro-temporal weights were measured with stimuli where the level of the three narrowband noises randomly and independently changed every 100 ms. The data consistently showed that (i) the first 300 ms of the sounds had a greater influence on overall loudness perception than later temporal portions (primacy effect), and (ii) the lowest noise band contributed significantly more to overall loudness than the higher bands. The temporal weights did not differ between the three frequency bands. Notably, the spectral weights and temporal weights estimated from the conditions with only spectral or only temporal variability were very similar to the corresponding weights estimated in the spectro-temporal condition. The results indicate that the temporal and the spectral weighting of the loudness of a time-varying sound are independent processes. The spectral weights remain constant across time, and the temporal weights do not change across frequency. The results are discussed in the context of current loudness models.

Patent
28 Nov 2012
TL;DR: In this article, the authors proposed a method of virtually tuning an audio system that incorporates an acoustic compensation system, where the audio system is adapted to play audio signals in a listening environment over one or more sound transducers.
Abstract: A method of virtually tuning an audio system that incorporates an acoustic compensation system, where the audio system is adapted to play audio signals in a listening environment over one or more sound transducers. The acoustic compensation system has an audio sensor located at a sensor location in the listening environment. The transfer functions from each sound transducer to the audio sensor location are inherent. The method contemplates recording noise at the sensor location, and creating virtual transfer functions from each sound transducer to the sensor location based on the inherent transfer functions from each sound transducer to the sensor location. Audio signals are processed through the virtual sound transducer to sensor location transfer functions. A virtual sensor signal is created by combining the audio signals processed through the virtual sound transducer to sensor location transfer functions with the noise recorded at the sensor location.

Journal ArticleDOI
TL;DR: The model which is presented as one of the solutions is based on two stages of operation with the first stage based on the ALE (Adaptive Line Enhancer) filters and the second stage on NLMS (Normalized Least Mean Square) filter.
Abstract: The basic theme of our paper is to implement a new idea of noise reduction in the real time applications using the concepts of adaptive filters. Our model which is presented as one of the solutions is based on two stages of operation with the first stage based on the ALE (Adaptive Line Enhancer) filters and the second stage on NLMS (Normalized Least Mean Square) filter. The first stage reduces the sinusoidal noise from the input signal and the second stage reduces the wideband noise. Two input sources of voice are used; one for the normal speech and the other for the noise input, using separate microphones for both signals. The first signal is of the corrupted speech signal and the second signal is of only the noise containing both wideband and narrowband noise. In the first stage the narrowband noise is reduced by using the ALE technique. The second stage gets a signal with ideally only the wideband noise which is reduced using the NLMS technique. In both the stages the concerned algorithms are used to update the filter coefficients in such a way that the noise is cancelled out from the signal and a clean speech signal is heard at the output. DOI: http://dx.doi.org/10.11591/ijece.v2i3.246

Journal ArticleDOI
TL;DR: A Bayesian method based on the reversible-jump Metropolis-Hastings algorithm for joint detection and removal of impulsive noise in audio signals is devised.
Abstract: Impulsive noise, also known as clicks, is a very common type of distortion in old gramophone recordings. Existing methods (both heuristic and statistical) for removal of this type of defect usually do not exploit its underlying physical generation. This work proposes a model in which each click is individually modeled, which is more physically meaningful. A Bayesian method based on the reversible-jump Metropolis-Hastings algorithm for joint detection and removal of impulsive noise in audio signals is devised. Simulations with artificial and real audio signals as well as comparisons with competing approaches are presented to illustrate and validate the proposed method.