| 1 | module mid_side |
| 2 | implicit none |
| 3 | contains |
| 4 | |
| 5 | subroutine mid_side_sub(inbuf, outbuf, vocal_gain, n) |
| 6 | ! inbuf : real(8) array of length 2*N (interleaved stereo: |
| 7 | ! L,R,L(ol),R,...) |
| 8 | ! outbuf : real(8) array, same length, to receive processed sam- |
| 9 | ! -ples |
| 10 | ! vocal_gain : real(8) scalar in [0,1] |
| 11 | ! |
| 12 | !f2py intent(in) :: inbuf, vocal_gain, n |
| 13 | !f2py intent(out) :: outbuf |
| 14 | !f2py depend(n) :: inbuf, outbuf |
| 15 | integer, intent(in) :: n |
| 16 | real(8), intent(in) :: inbuf(2*n) |
| 17 | real(8), intent(out) :: outbuf(2*n) |
| 18 | real(8), intent(in) :: vocal_gain |
| 19 | integer :: i |
| 20 | real(8) :: L, R, mid, side, out |
| 21 | |
| 22 | do i = 1, n |
| 23 | ! extract left and right channels of frame i |
| 24 | L = inbuf(2*(i-1) + 1) |
| 25 | R = inbuf(2*(i-1) + 2) |
| 26 | |
| 27 | ! capture the mids and stereo-only shite |
| 28 | mid = 0.5d0 * (L + R) |
| 29 | side = 0.5d0 * (L - R) |
| 30 | |
| 31 | ! if gain is 1.0, both instrumentals and vocals (as mid) |
| 32 | ! otherwise 0.0, just instrumental, hope all goes well ;) |
| 33 | out = side + vocal_gain * mid |
| 34 | |
| 35 | ! writeback the mixed sample to the bout uffa |
| 36 | outbuf(2*(i-1) + 1) = out |
| 37 | outbuf(2*(i-1) + 2) = out |
| 38 | end do |
| 39 | end subroutine mid_side_sub |
| 40 | |
| 41 | end module mid_side |