Acoustic Echo Cancellation Software AEC Providing Reliable Signal Processing Solutions Since 2001 • • • • • • • • • • • • • • • • • • • • • • • ACOUSTIC ECHO CANCELATION DSP ALGORITHMS has a long history providing reliable acoustic echo cancellation solutions. Our AEC solutions have been used in pioneering projects such as the British Telecom's VoIP client on Windows Mobile smartphones back in 2006 when smartphones were dominated by Windows Mobile devices. Back then smartphone application processors used to operate at maximum speed of 200 MHz and needed to run a complete VoIP client including the AEC on top of the Windows Mobile operating system, and all had to be responsive with good audio quality. With today's multiple cores and GHz processors, AEC audio quality is more important than resource consumption, and our AEC solutions have been evolving with market requirements like no others, improving quality while keeping the robust features intact. Today, our acoustic echo cancellation solutions are used in all communication and conferencing markets where an AEC has an added value, from large multi-microphone installed audio systems to tiny mobile devices.

What professionals say about our AEC Solutions William Westlake, product manager at British Telecom after testing the Microsoft VoIP client with DSP ALGORITHMS AEC plug-in on Windows Mobile 6.0: 'The Voice Quality is now superb, better than GSM and maybe as good as PSTN.' Mark Hemmer, after testing Symetrix' SymNet Designer 6.0: 'I loaded 6.0 into the system for testing in an Auditorium that seats up 500 people. This location has over 40 audience microphones used for questions and answers, plus another 4 wireless and 5 wired microphones on the platform, plus a podium microphone. Morphvox Pro Best Woman Settings_omnibox. They regularly do both video and teleconferencing from this location and due to the size of the room, PA is mandatory. I submixed all 50 microphones through 2 automixers and simply inserted a SymNet 6.0 single channel AEC in the signal path. I was amazed at how well it worked. This Facility uses a Polycom for video conference and A Gentner DH20 for teleconference, both of these items work well but we would still notice some glitches and echo at times probably due to the extreme environment.

Running the SymNet 6.0 AEC in circuit with these two devices completely removed this problem with no artifacts. With the internal AEC in the Gentner and Polycom bypassed, the system was equally problem free.' SOURCES OF ACOUSTIC ECHO Acoustic echo is generated whenever an application plays sound to a loudspeaker and at the same time records sound from a microphone located in the same listening space. Examples of such applications are speakerphones, audio and video conferencing, hands-free car kits, and many others. The figure shows one side of a full-duplex communication application in which the acoustic echo problem arises. The far-end voice signal received from the communication channel is played through a loudspeaker. In addition to the voice of the near-end user, the microphone also picks up sounds directly emitted from the loudspeaker and their reflections off the room walls, ceiling, floor, furniture, and other near-by objects (the acoustic echo), as well as background noise.

If nothing is done to remove this echo from the microphone signal before transmitting it, the far-end talker will hear her own voice distorted and delayed by the communication channel. The longer the channel delay, the more annoying the echo becomes until natural conversation becomes impossible. Full-duplex communication systems make use of an Acoustic Echo Canceller (AEC) to prevent the acoustic echo from being transmitted back to the far-end. The AEC basically tries to estimate the echo and subtracts the estimated echo from the microphone signal as shown in the figure. To successfully estimate the echo, an AEC makes use of an adaptive digital filter.

The filter coefficients are adjusted in real-time to model the impulse response between the loudspeaker and the microphone. For more in depth understanding of acoustic echo cancellers, their internal components, algorithms, and performance metrics, please refer to our. PERFORMANCE Our AEC solution has been optimized in quality, features, and performance based on extensive field testing and valuable customer feedback over the years.

It includes advanced features that are required in modern high end conferencing and communication applications such as fast convergence, low processing delay, robustness during double talk, microphone muting support, automatic estimation and compensation of initial delay, performance reporting, and much more. CODE PERFORMANCE Efficient implementation at the algorithm level as well as at the code level resulted in unparalleled performance. For instance a single without any external memory can implement up to 8 channels of echo cancellers, each channel has 250 ms echo tail length at 48 kHz audio sampling rate, with plenty of MIPS and memory left over for other tasks. QUALITY PERFORMANCE The sample audio files below demonstrate the audio quality of the processed speech signal during extended double-talk periods.

Up vote 0 down vote. If you are doing a commercial project that this should be easy. You can integrate a commercial audio cancellation software in your VoIP application. Htc Desire Echo Cancellation Software: Acoustic: Echo And The. And 3D-sound positioning * Acoustic Echo Cancellation. Free to try and free programs for.

The female voice in the unprocessed microphone signal (LEFT side) is the echo that must be removed, while the male voice is the voice of the local conference participant that must be preserved. The signal at the RIGHT side shows how the AEC can remove the female voice entirely without distorting the male speech. The image at the left shows the spectral contents of the unprocessed microphone signal, while the image at the right shows the spectral contents of the processed signal. Microphone Signal AEC Output FEATURES • Low algorithm processing delay; defined by the user-adjustable block length. • Supports multiple loudspeakers and multiple microphones. • Complies fully with G.167, P.340, and VDA (category 1). • Employs a robust and efficient block frequency domain adaptive algorithm.

• Provides superior and consistent single-talk echo reduction of 80 dB in any acoustic environments. • Provides stable echo reduction of 40 dB or more during double-talk periods. • Convergence rate up to 100 dB per second.

• Echo tail length is user adjustable. • A multichannel high quality echo suppressor is also included which further reduces any remaining residual echo with negligible double-talk distortion.

• Echo suppressor can be enabled or disabled in real-time • True Comfort Noise Generator that accurately estimates and tracks the background noise spectrum and level • Works at any sampling frequency without any calibration or modification. It has been already deployed in top quality products running at sample rates ranging from 8kHz to 48kHz. • Provides consistent performance in all acoustic environments, from a small car with a reverberation time of less than 100 ms to a large conference hall with reverberation time of several seconds. • Trivial to integrate due to its simple Application Programming Interface. • Fully configurable.

System designers have complete control on algorithm parameters. • Already lab and field tested on several fixed-point and floating-point processors and DSPs with and without an operating system. • Supported on all major desktop, mobile, and embedded platforms. • Floating-point and Fixed-point implementations optimized for several general purpose processors, microcontrollers, as well as digital signal processors are directly available. • Proven excellent performance in many high end applications including installed audio and video conferencing, Unified Collaboration, hands-free telephones, and consumer electronics. DEMONSTRATIONS Several demonstration are available on different embedded, mobile, and desktop platforms. A multichannel AEC demonstration is also directly available on the.

To request one of those demonstrations. Copyright © DSP ALGORITHMS, All rights reserved.

Echo Cancellation is used to enhance speech for Radio, Mobile, VoIP and Voice applications VOCAL offers a range of echo cancellation solutions including acoustic echo cancellers (AEC) and line / network echo cancellers (LEC / NEC). We have extensive experience in the development, integration, and configuration of echo cancellation solutions in a wide variety of products.

To discuss your echo cancellation application requirements. Echo Cancellation is the reduction of the reflected copies of a direct path wave in a signal. In telephony, the source of these reflections can be generated electrically due to an impedance mismatch in the transmission path or as a result of an acoustic and/or mechanical coupling between a loudspeaker and a microphone, usually because they are in the same physical enclosure. For acoustic/mechanical coupling an Acoustic Echo Canceller (AEC) is required; whereas, a Line Echo Canceller (LEC) is used to address impedance mismatch. Acoustic Echo Cancellation Acoustic Echo Cancellation is an essential part of providing speech enhancement (or voice quality enhancement) to any telephone communication. An (AEC) operates on the digitally sampled audio signals of the communication device. The transfer function of the acoustic environment from the loudspeaker to the microphone on the device is estimated to cancel the received echoes from the microphone signal.

Line/Network Echo Cancellation uses voice activated devices placed in the 4-wire portion of a circuit (which may be an individual circuit path or a path carrying a multiplexed signal) and are used for reducing the echo by subtracting an estimation from the circuit echo. They may be characterized by whether the transmission path or the subtraction of the echo is by analogue or digital means.

Adaptive Filters An is used in voice echo cancellation to accommodate the time varying nature of the echo path. The filter learns the path when the far-end speaker is talking and the near-end speaker is silent and adjusts its coefficients (transfer function) according to the algorithm optimization criterion. Echo Tail Length Echo tail length is considered the length of the.

The required length of the tail is dependent on the application. For line echoes the impulse is generally in the range of 8 to 32ms, while acoustic impulse responses can be on the order of 100ms. Double-Talk Detection For an adaptive filter to learn the echo path it must have an undisturbed reference signal to adapt to. Unfortunately, in full-duplex communications, this scenario cannot be guaranteed as the near-end speaker may want to interrupt the far-end speaker. In other words, the near-end and far-end speakers will be talking simultaneously (double-talk), resulting in disturbances in the reference signal. These disturbances will result in divergent behavior of the adaptive filter and is required to slow adaptation of the filter and prevent divergence.

Non-Linear Processing Non-linear processing is the removal of residual echo left by the adaptive filter. Residual echoes are the un-modeled components of the echo path. Most adaptive filters are linear and can only cancel the linear portions of the echo path. Thus the nonlinear portions cannot be removed via the adaptive filter and a residual echo suppressor follows the filter to portions of the echo that remain. More Information • • • • • • • • •.

I used to have a motherboard with Realtek HD Audio drivers. Although the driver and bundled software were clunky, annoying, and redundant, surprisingly it had features for Noise Suppression and Echo Cancellation when using microphones.

I have been taking this for granted as I work in data centers throughout the week, and I need to make calls over skype/google. Unfortunately the receiving end hears the blasting noise of air conditioners in the background. I later switched to a computer that uses VIA drivers, also with a bundle of clunky drivers. Unfortunately, they don't have any of these features. So I've been looking hard, but can't find any software that can perform the noise cancellation. It seems like it would need to hook in the driver level, but maybe this can be a generic filter that is used by applications that need to interface with the microphone. Any information would be useful.

Closed as off-topic by,,,, May 26 '14 at 19:10 This question appears to be off-topic. The users who voted to close gave this specific reason: • 'Questions seeking product, service, or learning material recommendations are off-topic because they become outdated quickly and attract opinion-based answers. Instead, describe your situation and the specific problem you're trying to solve.

Share your research. On how to properly ask this type of question.'

– Nifle, Tog, Kevin Panko, Ramhound, soandos If this question can be reworded to fit the rules in the, please. There are basically two scenarios here, noise reduction and echo suppression, which are very different beasts. I am more familiar with echo suppression (AEC), and to do this properly it needs to be done at the lowest level possible as close to the captured mic input and playback hardware as possible.

Ideally the device driver would be the perfect place to put it, but few windows drivers support it probably because most good AEC algorithms cost money to license. It can be done at the program/application level if you can access the buffer immediately as it has been recorded, and the buffer that has just been played. This is usually done in the application, and each application does it slightly differently if at all. So the answer to the echo cancellation is No I do not believe there is generic software or filters that can do AEC. Noise suppression is a different issue and requires some well understood algorithms be applied to the recorded microphone data before passing onto the application, so in this case I think it would be possible to apply a filter to the mic and generic application level software (or drivers) should be available, unfortunately I am not aware of any.