我每0.03秒只能得到735个频率的音频数据。
我想弄清楚怎样才能得到每帧的频谱。下面的代码每帧只返回735个数据（因为samples_in_frame是735，这是每帧的样本数），但是我想得到0.03秒样本的整个~20，000 hz。我该怎么做呢？
path：波形文件的路径
second_start：以秒为单位的进程起始点，0
second_length：处理时间（秒），10
frame_rate：每秒多少帧，60

fn fft_this(mut buffer: Vec<Complex<f64>>, samples_in_frame: usize) -> Vec<f64> {
    let mut planner = FftPlanner::new();

    let fft = planner.plan_fft_forward(samples_in_frame);

    fft.process(&mut buffer[..]);

    let mut frame_data: Vec<f64> = Vec::with_capacity(samples_in_frame);

    for i in 0..samples_in_frame {
        frame_data.push(buffer[i].norm())
    }

    return frame_data;
}

#[tauri::command]
pub fn analyze(
    path: &str,
    second_start: f64,
    second_length: f64,
    frame_rate: f64,
) -> Vec<Vec<f64>> {
    let wave_file: Wave64 = Wave64::load(path).expect("Could not load wave.");

    let samples_start: f64 = second_start * wave_file.sample_rate();
    let samples_in_each_frame: usize = (wave_file.sample_rate() / frame_rate) as usize;

    let frames_in_length: usize = (second_length * frame_rate) as usize;

    let mut wave_buffer: Vec<Vec<f64>> = vec![];

    for frame_index in 0..frames_in_length {
        let mut frame_buffer: Vec<Complex<f64>> = vec![];

        for sample_index in 0..samples_in_each_frame {
            let buffer_index: usize = frame_index * sample_index + samples_start as usize;

            frame_buffer.push(Complex {
                re: wave_file.at(0, buffer_index),
                im: 0.0,
            });
        }

        let processed_frame: Vec<f64> = fft_this(frame_buffer, samples_in_each_frame);

        wave_buffer.push(processed_frame);
    }

    return wave_buffer;
}