Correct comments

pull/16/merge
boblark 1 year ago
parent b056dab06e
commit 6bc40028de
  1. 16
      AudioFilter90Deg_F32.h

@ -2,7 +2,7 @@
* AudioFilter90Deg_F32.h
* 22 March 2020 Bob Larkin
* Parts are based on Open Audio FIR filter by Chip Audette:
*
*
* Chip Audette (OpenAudio) Feb 2017
* - Building from AudioFilterFIR from Teensy Audio Library
* (AudioFilterFIR credited to Pete (El Supremo))
@ -26,7 +26,7 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
/*
* This consists of two uncoupled paths that almost have the same amplitude gain
* but differ in phase by exactly 90 degrees. See AudioFilter90Deg_F32.cpp
@ -34,10 +34,10 @@
* as that produces an easily achievable integer sample period delay. In
* float, the ARM FIR library routine will handle odd numbers.\, so no zero padding
* is needed.
*
*
* No default Hilbert Transform is provided, as it is highly application dependent.
* The number of coefficients is an odd number with a maximum of 250. The Iowa
* Hills program can design a Hilbert Transform filter. Use begin(*pCoeff, nCoeff)
* The number of coefficients is an odd number with a maximum of 251. The Iowa
* Hills program can design a Hilbert Transform filter. Use begin(*pCoeff, nCoeff)
* in the .INO to initialize this block.
*
* Status: Tested T3.6 and T4.0. No known bugs.
@ -46,7 +46,7 @@
* pCoeff = pointer to array of F32 Hilbert Transform coefficients
* nCoeff = uint16_t number of Hilbert transform coefficients
* showError(e); Turns error printing in update() on (e=1) and off (e=0). For debug.
* Examples:
* Examples:
* ReceiverPart1.ino
* ReceiverPart2.ino
* Time: Depends on size of Hilbert FIR. Time for main body of update() including
@ -56,6 +56,8 @@
* 251 tap Hilbert (including 0's) 646 microseconds
* Same 121 tap Hilbert on T4.0 is 57 microseconds per update()
* Same 251 tap Hilbert on T4.0 is 114 microseconds per update()
*
* Rev 7 Feb 23 - Corrected type cast and comments. RSL
*/
#ifndef _filter_90deg_f32_h
@ -98,7 +100,7 @@ public:
// For the equalizing delay in q, if n_coeffs==19, n_delay=9
// Max of 251 coeffs needs a delay of 125 sample periods.
n_delay = (uint8_t)((n_coeffs-1)/2);
n_delay = (uint16_t)((n_coeffs-1)/2);
in_index = n_delay;
out_index = 0;
for (uint16_t i=0; i<256; i++){

Loading…
Cancel
Save