FFT implementation boiler

src/audio/fft.rs

@@ -0,0 +1,29 @@
+use crate::utils::FFTResult;
+use std::collections::VecDeque;
+
+pub struct FFTFrame {
+    buffer: VecDeque<[[i16; 480]; 2]>,
+}
+
+impl FFTFrame {
+    pub fn new() -> FFTFrame {
+        let mut frame = FFTFrame {
+            buffer: VecDeque::new(),
+        };
+        for _ in 0..5 {
+            frame.push([[0; 480]; 2]);
+        }
+        frame
+    }
+
+    pub fn push(&mut self, new_samples: [[i16; 480]; 2]) {
+        if self.buffer.len() == 5 {
+            self.buffer.pop_front();
+        }
+        self.buffer.push_back(new_samples);
+    }
+
+    pub fn compute(&self) -> FFTResult {
+        unimplemented!()
+    }
+}

src/audio/mod.rs

@@ -1,4 +1,5 @@
 use std::{
+    collections::VecDeque,
     sync::{
         mpsc::{channel, Sender},
         Arc,
@@ -9,6 +10,7 @@ use std::{
 use std::sync::mpsc::Receiver;
 
 use codec::DecoderContext;
+use fft::FFTFrame;
 
 use crate::{config::Settings, player::PlayerEvent, utils::Error};
 
@@ -31,6 +33,7 @@ pub struct SoundManager {
     decoder_context: DecoderContext,
     playing: bool,
     volume: f64,
+    fft_frame: FFTFrame,
 }
 
 pub fn init(
@@ -67,5 +70,6 @@ pub fn init(
 
 mod codec;
 mod errors;
+mod fft;
 mod pw;
 mod sound_mgr;

src/audio/sound_mgr.rs

@@ -1,4 +1,5 @@
 use std::{
+    collections::VecDeque,
     sync::{
         mpsc::{channel, Receiver, Sender, TryRecvError},
         Arc,
@@ -10,12 +11,12 @@ use std::{
 use crate::{
     config::Settings,
     player::PlayerEvent,
-    utils::{new_pw_pod, time_rem, Error},
+    utils::{new_pw_pod, time_rem, Error, FFTResult},
 };
 
 const VOLUME_CHANGE_INTERVAL: f64 = 0.05;
 
-use super::{codec, errors::AudioError, pw, AudioEvent, SoundManager};
+use super::{codec, errors::AudioError, fft::FFTFrame, pw, AudioEvent, SoundManager};
 
 impl SoundManager {
     pub fn init(
@@ -49,6 +50,7 @@ impl SoundManager {
             decoder_context,
             playing: false,
             volume: 1.0,
+            fft_frame: FFTFrame::new(),
         })
     }
     pub fn begin(&mut self) -> Result<(), Error> {
@@ -81,8 +83,23 @@ impl SoundManager {
         }
     }
 
+    fn fft_compute(&mut self, frame: &[u8]) -> FFTResult {
+        let mut samples = [[0; 480]; 2];
+        for i in 0..frame.len() / 4 {
+            for j in 0..2 {
+                let mut val_buff = [0; 2];
+                val_buff.copy_from_slice(&frame[4 * i + 2 * j..4 * i + 2 * j + 2]);
+                samples[i][j] = i16::from_le_bytes(val_buff);
+            }
+        }
+        self.fft_frame.push(samples);
+        self.fft_frame.compute()
+    }
+
     fn push_samples(&mut self) -> Result<(), Error> {
         let (mut frame, fetch_more) = self.decoder_context.next_sample();
+        let bins = self.fft_compute(frame.as_slice());
+        self.player_chan.send(PlayerEvent::FFTBins(bins))?;
         self.adjust_volume(frame.as_mut_slice());
         self.sample_in.send(frame)?;
         match fetch_more {

src/player/mod.rs

@@ -13,7 +13,7 @@ use crate::{
     audio::AudioEvent,
     config::Settings,
     ssonic::{response::Song, APIEvent},
-    utils::Error,
+    utils::{Error, FFTResult},
 };
 
 pub enum PlayerEvent {
@@ -23,6 +23,7 @@ pub enum PlayerEvent {
     PlayNext,
     AddAudioChunk(usize),
     FetchChunk,
+    FFTBins(FFTResult),
 }
 
 pub struct Player {

src/utils.rs

@@ -75,3 +75,5 @@ pub fn time_rem(start_time: SystemTime, target_dur: Duration) -> Result<Duration
     let time_since = SystemTime::now().duration_since(start_time)?;
     Ok(target_dur.saturating_sub(time_since))
 }
+
+pub struct FFTResult {}