From 9de43b7281dfc2e71e3a52d483318a5d2d140e77 Mon Sep 17 00:00:00 2001
From: gursi26 <gursimar.batra@gmail.com>
Date: Sat, 2 Mar 2024 19:47:18 -0500
Subject: [PATCH] added initial visualizer demo with raylib + spectrum-analyzer

---
 visualizer-trial/Cargo.toml  |  12 ++++
 visualizer-trial/src/main.rs | 130 +++++++++++++++++++++++++++++++++++
 2 files changed, 142 insertions(+)
 create mode 100644 visualizer-trial/Cargo.toml
 create mode 100644 visualizer-trial/src/main.rs

diff --git a/visualizer-trial/Cargo.toml b/visualizer-trial/Cargo.toml
new file mode 100644
index 0000000..010d06e
--- /dev/null
+++ b/visualizer-trial/Cargo.toml
@@ -0,0 +1,12 @@
+[package]
+name = "visualizer-trial"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+itertools = "0.12.1"
+raylib = "3.7.0"
+rodio = "0.17.3"
+spectrum-analyzer = "1.5.0"
diff --git a/visualizer-trial/src/main.rs b/visualizer-trial/src/main.rs
new file mode 100644
index 0000000..63f5fed
--- /dev/null
+++ b/visualizer-trial/src/main.rs
@@ -0,0 +1,130 @@
+#![allow(unused_imports, dead_code, unused)]
+
+use itertools::Itertools;
+use rodio::cpal::PlayStreamError;
+use rodio::{source::Source, Decoder, OutputStream};
+use spectrum_analyzer::scaling::divide_by_N_sqrt;
+use spectrum_analyzer::windows::hann_window;
+use spectrum_analyzer::{samples_fft_to_spectrum, FrequencyLimit};
+use std::fs::File;
+use std::io::{stdout, BufReader, Write};
+use std::usize;
+// use macroquad::prelude::*;
+use std::{thread, time};
+use raylib::prelude::*;
+
+const FREQUENCY_RESOLUTION: u32 = 50;
+const FREQ_WINDOW_LOW: f32 = 0.0;
+const FREQ_WINDOW_HIGH: f32 = 20000.0;
+const MONO_SCALING_FACTOR: i32 = 10;
+const FFT_FPS: u32 = 30;
+const FFT_WINDOW: i32 =
+    ((256 as u64 / 107 as u64) * FREQUENCY_RESOLUTION as u64).next_power_of_two() as i32;
+
+
+// const AUDIO_PATH: &str = "/Users/gursi/Desktop/60 BPM - Metronome-[AudioTrimmer.com].mp3";
+const AUDIO_PATH: &str = "/Users/gursi/Desktop/gurenge.mp3";
+
+
+
+
+fn main() {
+    let fft = get_fft();
+    let mut i = 0;
+
+    let (mut rl, thread) = raylib::init()
+        .size(640, 480)
+        .title("audio-visualizer-trial")
+        .build();
+    rl.set_target_fps(FFT_FPS);
+
+    let (_stream, stream_handle) = OutputStream::try_default().unwrap();
+    let file = BufReader::new(File::open(AUDIO_PATH).unwrap());
+    let source = Decoder::new(file).unwrap();
+    stream_handle.play_raw(source.convert_samples());
+
+    while !rl.window_should_close() {
+        let mut d = rl.begin_drawing(&thread);
+
+        d.clear_background(Color::BLACK);
+        if i >= fft.len() {
+            break;
+        }
+
+        let fft_chunk = &fft[i as usize];
+        let (h, w) = (d.get_screen_height(), d.get_screen_width());
+        let bar_start_idxs = (0..((w as i32) + 1)).step_by(w as usize / FREQUENCY_RESOLUTION as usize).collect::<Vec<i32>>();
+
+        for j in 0..(FREQUENCY_RESOLUTION as usize) {
+            let curr_fft_value = (fft_chunk[j] * h as f32 * 2.0) as i32;
+            let (start_x_id, end_x_id) = (bar_start_idxs[j], bar_start_idxs[j + 1]);
+            d.draw_rectangle(start_x_id, h - curr_fft_value, end_x_id - start_x_id, curr_fft_value, Color::GREEN);
+        }
+         i += 1;
+    }
+}
+
+fn get_fft() -> Vec<Vec<f32>> {
+    let (_stream, stream_handle) = OutputStream::try_default().unwrap();
+    let file = BufReader::new(File::open(AUDIO_PATH).unwrap());
+    let source = Decoder::new(file).unwrap();
+
+    let n_channels = source.channels() as i32;
+    let sample_rate = source.sample_rate() as i32;
+    println!("{}, {}", n_channels, sample_rate);
+
+    println!("Collecting...");
+
+    // Collecting takes too long
+    let sample_vec: Vec<i32> = source.map(|x| x as i32).collect();
+    println!("{}", sample_vec.len());
+
+    let mut output_vec = Vec::new();
+
+    let (mut min, mut max): (f32, f32) = (100.0, 0.0);
+
+    for x in sample_vec.chunks((sample_rate * n_channels) as usize / FFT_FPS as usize) {
+        let frame = &x[..(FFT_WINDOW as usize * n_channels as usize)];
+        let mut samples = [0.0; FFT_WINDOW as usize];
+        for (i, stereo) in frame.chunks(n_channels as usize).enumerate() {
+            samples[i] = stereo
+                .iter()
+                .map(|x| x.clone() as f32 / (n_channels * MONO_SCALING_FACTOR) as f32)
+                .sum::<f32>();
+        }
+
+        let hann_window = hann_window(&samples);
+        let spectrum_hann_window = samples_fft_to_spectrum(
+            &hann_window,
+            sample_rate as u32,
+            FrequencyLimit::Range(FREQ_WINDOW_LOW, FREQ_WINDOW_HIGH),
+            Some(&divide_by_N_sqrt),
+        )
+        .unwrap();
+
+        let curr_vec = spectrum_hann_window
+            .data()
+            .into_iter()
+            .map(|(f, fval)| fval.val())
+            .collect::<Vec<f32>>();
+
+        for val in curr_vec.iter() {
+            max = max.max(*val);
+            min = min.min(*val);
+        }
+        output_vec.push(curr_vec);
+    }
+
+    let scale = 1.0 / (max - min);
+    for j in 0..output_vec.len() {
+        for k in 0..output_vec[j].len() {
+            output_vec[j][k] -= min;
+            output_vec[j][k] *= scale;
+        }
+    }
+
+
+    println!("Min: {}, Max: {}", min, max);
+    println!("{}, {}", output_vec.len(), output_vec[0].len());
+    output_vec
+}