The libdsp-x15 library was created to offload typical audio processing operations to the C66x DSPs (integrated in AM5728 SoC of TI). Currently the library offers the following signal operations:
- Fast Fourier Transform (FFT)
- Inverse Fast Fourier Transform (IFFT)
- Biquad Filter (2nd order IIR filter (often used in audio applications due to stability))
The CTAG face2|4 Multichannel Audio Card driver has been succesfully ported to AM5728 SoC. The driver (compatible with BeagleBone Black/green and BeagleBoard.org - x15) has been merged in the offical BeagleBoard kernel and is ready to use by default in the BeagleBone images since end of 2016.
The BeagleBoard-X15 is a single board computer (SBC) based on AM5728 SoC by Texas Instruments.
AM5728 offers two integrated C66x DSPs, which can be used for real-time signal processing in asymmetric multiprocessor configurations.
Moreover the digital audio interface (DAI) of AM5728 is compatible with BeagleBone Black/Green.
An audio system consisting of our multi-channel audio card CTAG face2|4 and an easy to use DSP library would offer a powerful platform for real-time, low-latency audio processing and synthesis.
- Create library to make use of C66x DSPs
- Porting the CTAG face2|4 Audio Card drivers to AM5728 SoC (see project page or hackaday project)
The DSP library libdsp-x15 focuses on audio processing and offers the following signal operations.
|Fast Fourier transform (FFT)||Operation which transforms signal from time domain to frequency domain (spectrum). Often used for signal analysis and further processing in frequency domain (e.g. audio coding).|
|Inverse fast Fourier transform (IFFT)||Inverse operation of FFT which transforms signal from frequency domain back to time domain. Often used for additive synthesis.|
|Biquad filter||Two pole and two zero infinite impulse response (IIR) filter. Biquad filters are often used in audio applications due to its stability. To achieve a higher filter slope, biquad filters can be serially cascaded instead of using higher order IIR filters (can be highly sensitive to quantization errors of their coefficients => unstable).|