Function test_mel_spectrogram_sine_wave

cake-core/src/models/luxtts/mel.rs:202–216

()

    #[test]
    fn test_mel_spectrogram_sine_wave() {
        // 440Hz sine wave, should show energy in the corresponding mel bin
        let sample_rate = 24000;
        let duration = 0.5;
        let n_samples = (sample_rate as f32 * duration) as usize;
        let samples: Vec<f32> = (0..n_samples)
            .map(|i| (2.0 * std::f32::consts::PI * 440.0 * i as f32 / sample_rate as f32).sin())
            .collect();
        let mel = mel_spectrogram(&samples, 1024, 256, 100, sample_rate, &Device::Cpu, DType::F32).unwrap();
        let mel_data = mel.to_vec3::<f32>().unwrap();
        // Should have non-uniform energy distribution across mel bins
        let max_val: f32 = mel_data[0].iter().flat_map(|row| row.iter()).cloned().fold(f32::NEG_INFINITY, f32::max);
        let min_val: f32 = mel_data[0].iter().flat_map(|row| row.iter()).cloned().fold(f32::INFINITY, f32::min);
        assert!(max_val > min_val, "mel spectrogram should show energy variation");
    }
}