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Swap fftw in the stft example out for realfft

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The FFTW bindings can't statically link on Windows.
This commit is contained in:
Robbert van der Helm 2022-03-28 17:05:28 +02:00
parent b56c9892c0
commit 80c3fb8d51
3 changed files with 102 additions and 52 deletions
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65
Cargo.lock generated
View file

@ -1002,7 +1002,7 @@ dependencies = [
"fftw-sys",
"lazy_static 1.4.0",
"ndarray",
"num-complex",
"num-complex 0.3.1",
"num-traits",
"thiserror",
]
@ -1028,7 +1028,7 @@ checksum = "e8e3951d695cc2f17610cd041e87ebc15078d1af5eb8c6be77921381fc98b3fd"
dependencies = [
"fftw-src",
"libc",
"num-complex",
"num-complex 0.3.1",
]
[[package]]
@ -2138,7 +2138,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "6c0d5c9540a691d153064dc47a4db2504587a75eae07bf1d73f7a596ebc73c04"
dependencies = [
"matrixmultiply",
"num-complex",
"num-complex 0.3.1",
"num-integer",
"num-traits",
"rawpointer",
@ -2276,6 +2276,15 @@ dependencies = [
"num-traits",
]
[[package]]
name = "num-complex"
version = "0.4.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "26873667bbbb7c5182d4a37c1add32cdf09f841af72da53318fdb81543c15085"
dependencies = [
"num-traits",
]
[[package]]
name = "num-integer"
version = "0.1.44"
@ -2658,6 +2667,15 @@ version = "0.2.16"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "eb9f9e6e233e5c4a35559a617bf40a4ec447db2e84c20b55a6f83167b7e57872"
[[package]]
name = "primal-check"
version = "0.3.1"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "01419cee72c1a1ca944554e23d83e483e1bccf378753344e881de28b5487511d"
dependencies = [
"num-integer",
]
[[package]]
name = "proc-macro-error"
version = "1.0.4"
@ -2871,6 +2889,15 @@ version = "0.4.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "9ae028b272a6e99d9f8260ceefa3caa09300a8d6c8d2b2001316474bc52122e9"
[[package]]
name = "realfft"
version = "3.0.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "a83b876fe55da7e1bf5deeacb93d6411edf81eba0e1a497e79c067734729053a"
dependencies = [
"rustfft",
]
[[package]]
name = "redox_syscall"
version = "0.2.12"
@ -2991,6 +3018,20 @@ dependencies = [
"semver",
]
[[package]]
name = "rustfft"
version = "6.0.1"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "b1d089e5c57521629a59f5f39bca7434849ff89bd6873b521afe389c1c602543"
dependencies = [
"num-complex 0.4.0",
"num-integer",
"num-traits",
"primal-check",
"strength_reduce",
"transpose",
]
[[package]]
name = "rustybuzz"
version = "0.4.0"
@ -3308,10 +3349,16 @@ checksum = "a2eb9349b6444b326872e140eb1cf5e7c522154d69e7a0ffb0fb81c06b37543f"
name = "stft"
version = "0.1.0"
dependencies = [
"fftw",
"nih_plug",
"realfft",
]
[[package]]
name = "strength_reduce"
version = "0.2.3"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "a3ff2f71c82567c565ba4b3009a9350a96a7269eaa4001ebedae926230bc2254"
[[package]]
name = "svg_fmt"
version = "0.4.1"
@ -3445,6 +3492,16 @@ dependencies = [
"serde",
]
[[package]]
name = "transpose"
version = "0.2.1"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "95f9c900aa98b6ea43aee227fd680550cdec726526aab8ac801549eadb25e39f"
dependencies = [
"num-integer",
"strength_reduce",
]
[[package]]
name = "triple_buffer"
version = "6.0.0"

2
plugins/examples/stft/Cargo.toml
View file

@ -11,4 +11,4 @@ crate-type = ["cdylib"]
[dependencies]
nih_plug = { path = "../../../", features = ["assert_process_allocs"] }
fftw = "0.7.0"
realfft = "3.0"

87
plugins/examples/stft/src/lib.rs
View file

@ -1,9 +1,9 @@
use fftw::array::AlignedVec;
use fftw::plan::{C2RPlan, C2RPlan32, R2CPlan, R2CPlan32};
use fftw::types::{c32, Flag};
use nih_plug::prelude::*;
use realfft::num_complex::Complex32;
use realfft::{ComplexToReal, RealFftPlanner, RealToComplex};
use std::f32;
use std::pin::Pin;
use std::sync::Arc;
const WINDOW_SIZE: usize = 2048;
const OVERLAP_TIMES: usize = 4;
@ -17,51 +17,47 @@ struct Stft {
window_function: Vec<f32>,
/// The FFT of a simple low-pass FIR filter.
lp_filter_kernel: Vec<c32>,
lp_filter_kernel: Vec<Complex32>,
/// The algorithms for the FFT and IFFT operations.
plan: Plan,
/// Scratch buffers for computing our FFT. The [`StftHelper`] already contains a buffer for the
/// real values.
complex_fft_scratch_buffer: AlignedVec<c32>,
/// The algorithm for the FFT operation.
r2c_plan: Arc<dyn RealToComplex<f32>>,
/// The algorithm for the IFFT operation.
c2r_plan: Arc<dyn ComplexToReal<f32>>,
/// The output of our real->complex FFT.
complex_fft_buffer: Vec<Complex32>,
/// Scratch buffers for computing our FFT. RustFFT requires a separate scratch buffer. The
/// [`StftHelper`] already contains a buffer for the real values.
fft_scratch_buffer: Vec<Complex32>,
}
/// FFTW uses raw pointers which aren't Send+Sync, so we'll wrap this in a separate struct.
struct Plan {
r2c_plan: R2CPlan32,
c2r_plan: C2RPlan32,
}
unsafe impl Send for Plan {}
unsafe impl Sync for Plan {}
#[derive(Params)]
struct StftParams {}
impl Default for Stft {
fn default() -> Self {
let mut r2c_plan: R2CPlan32 =
R2CPlan32::aligned(&[WINDOW_SIZE], Flag::MEASURE | Flag::DESTROYINPUT).unwrap();
let c2r_plan: C2RPlan32 =
C2RPlan32::aligned(&[WINDOW_SIZE], Flag::MEASURE | Flag::DESTROYINPUT).unwrap();
let mut real_fft_scratch_buffer: AlignedVec<f32> = AlignedVec::new(WINDOW_SIZE);
let mut complex_fft_scratch_buffer: AlignedVec<c32> = AlignedVec::new(WINDOW_SIZE / 2 + 1);
let mut planner = RealFftPlanner::new();
let r2c_plan = planner.plan_fft_forward(WINDOW_SIZE);
let c2r_plan = planner.plan_fft_inverse(WINDOW_SIZE);
let mut real_fft_buffer = r2c_plan.make_input_vec();
let mut complex_fft_buffer = r2c_plan.make_output_vec();
let mut fft_scratch_buffer = r2c_plan.make_scratch_vec();
// Build a super simple low-pass filter from one of the built in window function
const FILTER_WINDOW_SIZE: usize = 33;
let filter_window = util::window::hann(FILTER_WINDOW_SIZE);
real_fft_scratch_buffer[0..FILTER_WINDOW_SIZE].copy_from_slice(&filter_window);
real_fft_buffer[0..FILTER_WINDOW_SIZE].copy_from_slice(&filter_window);
// And make sure to normalize this so convolution sums to 1
let filter_normalization_factor = real_fft_scratch_buffer.iter().sum::<f32>().recip();
for sample in real_fft_scratch_buffer.as_slice_mut() {
let filter_normalization_factor = real_fft_buffer.iter().sum::<f32>().recip();
for sample in &mut real_fft_buffer {
*sample *= filter_normalization_factor;
}
r2c_plan
.r2c(
&mut real_fft_scratch_buffer,
&mut complex_fft_scratch_buffer,
.process_with_scratch(
&mut real_fft_buffer,
&mut complex_fft_buffer,
&mut fft_scratch_buffer,
)
.unwrap();
@ -71,14 +67,12 @@ impl Default for Stft {
stft: util::StftHelper::new(2, WINDOW_SIZE),
window_function: util::window::hann(WINDOW_SIZE),
lp_filter_kernel: complex_fft_scratch_buffer
.iter()
.take(WINDOW_SIZE)
.copied()
.collect(),
lp_filter_kernel: complex_fft_buffer.clone(),
plan: Plan { r2c_plan, c2r_plan },
complex_fft_scratch_buffer,
r2c_plan,
c2r_plan,
complex_fft_buffer,
fft_scratch_buffer,
}
}
}
@ -146,19 +140,18 @@ impl Plugin for Stft {
OVERLAP_TIMES,
|_channel_idx, real_fft_scratch_buffer| {
// Forward FFT, the helper has already applied window function
self.plan
.r2c_plan
.r2c(
self.r2c_plan
.process_with_scratch(
real_fft_scratch_buffer,
&mut self.complex_fft_scratch_buffer,
&mut self.complex_fft_buffer,
&mut self.fft_scratch_buffer,
)
.unwrap();
// As per the convolution theorem we can simply multiply these two buffers. We'll
// also apply the gain compensation at this point.
for (fft_bin, kernel_bin) in self
.complex_fft_scratch_buffer
.as_slice_mut()
.complex_fft_buffer
.iter_mut()
.zip(&self.lp_filter_kernel)
{
@ -167,11 +160,11 @@ impl Plugin for Stft {
// Inverse FFT back into the scratch buffer. This will be added to a ring buffer
// which gets written back to the host at a one block delay.
self.plan
.c2r_plan
.c2r(
&mut self.complex_fft_scratch_buffer,
self.c2r_plan
.process_with_scratch(
&mut self.complex_fft_buffer,
real_fft_scratch_buffer,
&mut self.fft_scratch_buffer,
)
.unwrap();
},