VIDEO CONFERENCE DEVICE

• US 20100165071A1
• Filed: 05/01/2008
• Published: 07/01/2010
• Est. Priority Date: 05/16/2007
• Status: Abandoned Application

• Current Assignee: Yamaha Corporation
• Original Assignee: Yamaha Corporation
• Inventors: Ishibashi, Toshiaki, Tanaka, Ryo
• Application Number:
  US12/600,400
• Publication Number:
  US 20100165071A1
• Time in Patent Office: Days
• US Class Current: 348/14.80
• CPC Class Codes: H04M 9/082 using echo cancellers echo cancellers per se H04B3/23
• CPC Class Codes: H04N 7/142 Constructional details of the terminal equipment, e.g. arrangements of the camera and the display
• CPC Class Codes: H04N 7/15 Conference systems
• CPC Class Codes: H04R 3/02 for preventing acoustic reaction , i.e. acoustic oscillatory feedback specially adapted for hearing aids H04R25/453

Abstract

A video conference device capable of suppressing a processing burden of an echo canceller in such a situation that speakers, microphones, and a camera are arranged in close vicinity of a monitor is provided. A preliminary filter portion 18 is provided in a preceding stage of an echo canceller 19. The preliminary filter portion 18 has an LPF 181, a fixed filter 182, and a post processor 183. A controlling portion 14 sets a filter coefficient corresponding to a sound collecting beam signal that a signal selecting portion 17 selected, in the fixed filter 182. This filter coefficient is set to simulate a transfer function of an acoustic transfer system that feedbacks from the speakers to the microphones. A component of a low frequency band (e.g., 1 kHz or less) out of sound signals (input sound signals) being input into the speakers is input into the fixed filter 182, and a pseudo signal is produced. The pseudo signal (feedback component) is removed by the post processor 183, and a corrected sound collecting beam signal MSs is produced.

Claims

1. A video conference device, comprising:

an image picking-up portion which picks up an image;

a sound emitting portion which emits a sound;

a sound collecting portion which collects a sound;

a sound collection signal processing portion which applies a signal processing to a sound signal that is collected by the sound collecting portion to output a sound collecting signal;

an input signal processing portion which applies a signal processing to an input signal that is input from an outside, and inputs the input signal that is subjected to the signal processing to the sound emitting portion;

a fixed filter which applies a filtering to the input signal based on a filter coefficient;

a filter coefficient setting portion which sets a pseudo filter coefficient that simulates a transfer function of an acoustic transfer system which is extended from the sound emitting portion to the sound collecting portion, as the filter coefficient of the fixed filter;

a post processor which produces a corrected sound collecting signal by subtracting an output signal of the fixed filter from the sound collecting signal; and

an adaptive echo canceller which subtracts a pseudo echo signal, which is obtained by processing the input signal by an adaptive filter, from the corrected sound collecting signal produced by the post processor.

2. The video conference device according to claim 1, wherein the sound collecting portion has a microphone array in which a plurality of microphones are aligned;

wherein the sound collection signal processing portion includes;

a sound-collection beam producing portion for producing a plurality of sound collecting beam signals having a sound collecting directivity in a plurality of directions, by applying a delay processing to the sound signal picked up by the plurality of microphones and synthesizing delayed sound signals; and

a signal selecting portion for sensing a talker'"'"'s direction based on levels of sound volumes of the plurality of sound collecting beam signals, and outputting a sound collecting beam signal in the talker'"'"'s direction as the sound collecting signal;

wherein the filter coefficient setting portion sets the filter coefficient, which corresponds to the sound collecting beam signal that the signal selecting portion selects, out of a plurality of filter coefficients which correspond to the sound collecting directivities of the plurality of sound collecting beam signals produced by the sound-collection beam producing portion to the fixed filter, as the pseudo filter coefficient.

3. The video conference device according to claim 1, further comprising:

a band-pass filter provided at a preceding stage of the fixed filter to allow only a predetermined frequency band of the input signal to pass through.

4. The video conference device according to claim 3, wherein the band-pass filter is a low-pass filter whose pass band is below 1 kHz.

5. The video conference device according to claim 2, wherein the image picking-up portion changes a shooting condition, based on the talker'"'"'s direction sensed by the signal selecting portion.

6. The video conference device according to claim 2, wherein the signal selecting portion further includes a band pass filter that allows a main component band of a human voice to pass through, and senses the talker'"'"'s direction based on the signal levels of the plurality of sound collecting beam signals subjected to a band-pass filtering process by the band pass filter.