Speech enhancement on smartphone Voice Recording

Abstract

Speech enhancement is a challenging task in audio signal processing to enhance the quality of targeted speech signal while suppressing other noises. In the beginning, the speech enhancement algorithm growth rapidly from spectral subtraction, Wiener filtering, spectral amplitude MMSE estimator to Non-negative Matrix Factorization (NMF). Smartphone as a revolutionary device now is being used in all aspect of life including journalism; personally and professionally. Although many smartphones have two microphones (main and rear) the only main microphone is widely used for voice recording. This is why the NMF algorithm widely used for this purpose of speech enhancement. This paper evaluates speech enhancement on smartphone voice recording by using some algorithms mentioned previously. We also extend the NMF algorithm to Kulback-Leibler NMF with supervised separation. The last algorithm shows improved result compared to others by spectrogram and PESQ score evaluation.

For full paper please download here (submitted to ICOPIA 2016). For Octave code (obtained from single source separation: mini tutorial), and latex code please refer to this link.

AirDroid: WebApp untuk Koneksi Smartphone Android

Untuk mengkomunikasikan smartphone dan tablet berbasis android, selain melalui sshdroid seperti yang telah saya jelaskan disini, ternyata ada cara lain yang lebih praktis dan efisien, yakni menngunakan aplikasi AirDroid.

Konsep dasar aplikasi AirDroid ini adalah bahwa smartphone / tablet bukan seperti USB flashdisk, jadi ketika terhubung ke komputer, seharusnya menampilkan jenis-jenis data seperti gambar, musik, kontak telfon dan sejenisnya. Hal ini berbeda dengan ketika anda menghubungkan ponsel/tablet android anda dengan kabel USB, maka tampilan yang diperoleh berupa drive-drive sistem Android. Konsep tersebut diimplementasikan dengan tiga filosofi AirDroid: One less cable, One less screen dan One less worry.

Untuk memulai koneksi smartphone Android dengan PC, terlebih dahulu silakan download aplikasi AirDroid di Google Play. Setelah terinstall, silakan tekan ikon AirDorid dan akan muncul gambar seperti di bawah. Di layar PC anda silakan ketik alamat URL yang ditunjukkan oleh smartphone ini. Metode koneksi melalui URL ini lebih cepat karena hanya melalui interlan wlan saja daripada koneksi langsung ke web airdroid.com.

Screenshot AirDroid saat diaktikfkan di smartphone

How-to: Maximize Battery Life of Smartphone and Tablet

Step-by-step:

1. Use black wallpaper
If don't have one, you can use mine here.
2. Set low brightness
In Android: Setting >> Display >> Brightness
3. Use no animation
In Android: Setting >> Display >> Animation >> No Animation
4. Take the shortest time to turn off screen when inactive
In Android: Setting >> Display >> Screen timeout >> 15 seconds
5. Disable sound or keep in vibrate mode in some condition
lower your volume button or hold the power button and select silent mode
6. Disconnect wifi when screen turns off
In Android: Setting >> Wireless and Network >> Wifi Setting >> [option] Advanced >> Disconnect wifi when the screen turns off
7. Install battery saver app
I use JuiceDefender and Go Power Saver 

Those are my tips and tricks to maximize battery life based on my experience using several tablets and smartphones e.q: Lenovo IdeaPad A5, Asus Transformer Prime TF-201, Sony Xperia Tab S, Dell Streak Pro, Creative Ziio, Sharp Aquos 101, and Motorola Razr. The following is screenshot of my tablet Asus Transformer using black wallpaper to save battery, and it also shown the icon of battery saver application JuiceDefender.

Screenshot of my tablet: Transformer TF-201