Patent ID: 11924628
Assignee: HEAR360 INC
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H | IPC H

Claim 10:
11. A virtual surround sound process for loudspeaker systems comprising:
inputting a standard stereo audio source signal with a left information and a right information into a virtualization process;
extracting center image information from the stereo sound-source signal;
subtracting low frequency information from the extracted center image information and routing the result to a center audio path;
Mid-Side decode processing the extracted center image information with a low pass filter to extract mid and high frequency information and routing the result to a “Left (L)” and a “Right (R)” output path;
routing the Mid-Side decode processing output to the “Left (L)” and “Right (R)” output paths;
processing the Mid-Side decode processing output with a high pass filter to remove low frequency information, splitting the output thereof to a left side and a right side, processing the left side by an audio delay block to provide a delayed left side, and routing the delayed left side and right side to a left surround rear and a right surround rear output;
processing the left information and right information with a band pass filter to extract both high and low frequencies, leaving a left middle signal and a right middle signal with only middle frequencies present, at which the processed left middle signal and a right middle signal are then routed to “Left Side Surround (LSS)” and “Right Side Surround (RSS)” output paths;
summing the left information and right information to create a single mono audio source,
processing the single mono audio source with a Low Pass filter to remove middle and high frequency information, and then routing to a “Low Frequency Effects (LFE)” output path;
connecting the (L) output to a “Processing Bus A”;
connecting the (R) output path to a “Processing Bus B”;
connecting a Center (C) output path is connected to “Processing Bus A” and “Processing Bus B”
connecting a “Low Frequency Effects (LFE)” output path to “Processing Bus A” and “Processing Bus B”;
connecting a “Left Surround Rear (LSR)” output path to a convolution engine, processed by an HRTF filter with an externally controllable azimuth and elevation (impulse response), connected to a crosstalk cancelation processing block with a controllable loudspeaker width, and then connecting the output thereof to “Processing Bus A”;
connecting a “Right Surround Rear (RSR)” output to a first convolution engine, processed by a first HRTF filter with an externally controllable azimuth and elevation (impulse response), connected to crosstalk cancelation processing block with an controllable loudspeaker width, and then connecting the output thereof to “Processing Bus B”;
connecting the (LSS) output to a second convolution engine, processed by a second HRTF filter with an externally controllable azimuth and elevation (impulse response), connected to crosstalk cancelation processing block with a controllable loudspeaker width, and then connecting the output thereof to “Processing Bus A”;
connecting the (RSS) output to a convolution engine, processed by an HRTF filter with an externally controllable azimuth and elevation (impulse response), connected to crosstalk cancelation processing block with a controllable loudspeaker width, and then connecting the output thereof to “Processing Bus B”;
connecting the (TSL) output to a convolution engine, processed by an HRTF filter with a controllable azimuth and elevation (impulse response), connected to a crosstalk cancelation processing block with a controllable loudspeaker width, and then connecting the output thereof to “Processing Bus A”;
connecting the (TSR) output path to a convolution engine, processed by an HRTF filter with a controllable azimuth and elevation (impulse response), connected to crosstalk cancelation processing block with a controllable loudspeaker width, and then connecting the output thereof to “Processing Bus B”;
connecting the Processing Bus A to an equalization and dynamic control processing block, and then connecting the output thereof to a Left Loudspeaker;
connecting the Processing Bus B to an equalization and dynamic control processing block, and then connecting the output thereof to a Right Loudspeaker.