Abstract: A method for cleaning a breathing apparatus comprising a respiratory mask, by such precleaning activity as: providing the breathing apparatus in an externally contaminated state, providing a holder for the respiratory mask having at least one curved sealing face and stretching the respiratory mask onto the holder such that a sealing lip of the respiratory mask lies on the curved sealing face and closes off an interior of the respiratory mask, and the holder with the respiratory mask may be introduced into a precleaning chamber, exposing an outer side of the respiratory mask in the precleaning chamber to at least one precleaning fluid. And, after the precleaning, the respiratory mask may be released from the holder, introducing the respiratory mask into a primary cleaning chamber and exposing the respiratory mask, including an inner side of the respiratory mask that faces the interior, to a primary cleaning fluid.

Abstract: A method and device is described for estimating the subglottal air pressure during speech or singing from the intraoral air pressure in essentially real-time by using a type of peak detection and extrapolation means that holds peaks in the low-pass filtered pressure signal for a period of time sufficient to allow their interpretation as real-time subglottal pressure. An electronic circuit suitable for implementing this function is described.

Abstract: Artifacts occurring during frequency compression, in particular in the case of hearing aids, are avoided or reduced. The method compresses the frequency of an audio signal having a fundamental frequency and at least one harmonic. The audio signal is provided in a plurality of frequency channels. The harmonic of the audio signal is shifted or mapped from a first frequency channel of the plurality of frequency channels into a second frequency channel. In addition a frequency which is likewise harmonic with respect to the fundamental frequency is estimated in the second frequency channel, the harmonic being shifted or mapped onto the estimated frequency. As a result the harmonic pattern is preserved in the compressed signal and the artifacts are reduced.

Abstract: Embodiments of the invention provide a system, apparatus and methods for underwater voice communication by a diver to other divers and surface ships. In many embodiments, the system includes a mouthpiece voice communication apparatus having a microphone for sensing the diver's voice and an acoustic transducer that conducts sound via conduction through the diver's teeth and skull to the cochlea so as to allow the diver to hear sounds. The mouthpiece is adapted to be easily attached to portions of a SCUBA or other underwater breathing apparatus. It may also be attached to or integral with a snorkel or similar apparatus.

Abstract: Embodiments described herein provide a system, apparatus and methods to enable a diver to communicate more clearly with other divers or locations Embodiments process the speech to add clarity, or otherwise convert speech into an outputted form that is more intelligible e.g. so as to simulate the diver's unhindered speech. Embodiments provide hardware and software for receiving and recognizing hindered speech of a diver (e.g., speech hindered by a mouthpiece) and then augmenting the speech with generated output sounds corresponding to the intended speech sound or generating or replacing at least some of the diver's speech with synthesized words. The output sounds may be in the speaker's own voice or a synthesized voice. Embodiments may be configured to add clarity to and/or augment speech that is hindered by the wearing of a mouthpiece from a snorkel, SCUBA or other diving apparatus.

Abstract: A voice conversion apparatus stores, in a parameter memory, target speech spectral parameters of target speech, stores, in a voice conversion rule memory, a voice conversion rule for converting voice quality of source speech into voice quality of the target speech, extracts, from an input source speech, a source speech spectral parameter of the input source speech, converts extracted source speech spectral parameter into a first conversion spectral parameter by using the voice conversion rule, selects target speech spectral parameter similar to the first conversion spectral parameter from the parameter memory, generates an aperiodic component spectral parameter representing from selected target speech spectral parameter, mixes a periodic component spectral parameter included in the first conversion spectral parameter with the aperiodic component spectral parameter, to obtain a second conversion spectral parameter, and generates a speech waveform from the second conversion spectral parameter.

Abstract: A procedure and an apparatus for producing an image based on contrast discrimination in an image forming apparatus with one-dimensional or multidimensional image field.

Abstract: Disclosed is apparatus for and a method of decreasing the time duration of playback of recorded speech without distortion. Speech recorded at a normal rate is played back at a higher rate using two variable length buffers in alternating fashion to receive sampled speech segments. Threshold analysis logic circuitry is provided to continually compare the output voltage levels of both buffers and to switch the output between the buffers to a using device when the voltage level of both buffers is approximately zero and of an equal amplitude. In this way output to the using device consists of segments from both buffers joined with a minimum of generated noise and no associated dead zone without regard to any predetermined segment length.