Improved Audio Encryption Algorithm with Empirical Mode Decomposition and Random Bit Pool Integration

Abstract

In our work, we propose an improved voice encryption algorithm based on chaotic dynamics that makes the voice encryption algorithm more secure against attacks. The unique contribution of this work is the combination of SHA3-512 hash function, Empirical Mode Decomposition (EMD) operations, and an optimized random bit pool in a high-integrity encryption framework. The distinguishing feature is that the encryption key is obtained from a cryptographic quality random bit pool generated by optimization-based generators, exhibiting good statistical properties. This structure offers unpredictability beyond known key generation mechanisms. At the same time, the signal adaptive feature of EMD, encrypting only the residue component, has increased the computational efficiency and improved the algorithm's suitability for real-time applications. The dependence of the chaotic parameters on the seed value conditions and the use of a hybrid with an optimized random bit pool significantly improves the reliability of the encryption system. Experimental analysis statistically demonstrates that the algorithm shows low correlation, high entropy growth, and satisfactory decryption accuracy. Thus, it proves to be a significant contribution to the literature in terms of both cryptographic security and computational efficiency for voice encryption operations.

Keywords

• Audio Encryption
• Empirical Mode Decomposition (EMD)
• Optimization
• Cryptographic signal processing

Ampirik Mod Ayrıştırma ve Rastgele Bit Havuzu Entegrasyonu ile Geliştirilmiş Ses Şifreleme Algoritması

Abstract

Çalışmamızda, ses şifreleme algoritmasını saldırılara karşı daha güvenli hale getiren kaotik dinamiklere dayalı geliştirilmiş bir ses şifreleme algoritması öneriyoruz. Bu çalışmanın benzersiz katkısı, SHA3-512 hash fonksiyonu, Ampirik Mod Ayrıştırma (EMD) işlemleri ve optimize edilmiş bir rastgele bit havuzunun yüksek bütünlüklü bir şifreleme çerçevesinde birleştirilmesidir. Ayırt edici özellik, şifreleme anahtarının optimizasyon tabanlı jeneratörler tarafından üretilen ve iyi istatistiksel özellikler sergileyen kriptografik kalitede bir rastgele bit havuzundan elde edilmesidir. Bu yapı bilinen anahtar üretim mekanizmalarının ötesinde bir öngörülemezlik sunmaktadır. Aynı zamanda, EMD'nin yalnızca kalıntı bileşenini şifreleyen sinyal uyarlamalı özelliği, hesaplama verimliliğini artırmış ve algoritmanın gerçek zamanlı uygulamalar için uygunluğunu geliştirmiştir. Kaotik parametrelerin tohum değeri koşullarına bağlı olması ve optimize edilmiş rastgele bit havuzuna sahip bir hibritin kullanılması şifreleme sisteminin güvenilirliğini önemli ölçüde artırmaktadır. Deneysel analizler, algoritmanın düşük korelasyon, yüksek entropi büyümesi ve tatmin edici şifre çözme doğruluğu gösterdiğini istatistiksel olarak ortaya koymaktadır. Böylece, ses şifreleme işlemleri için hem kriptografik güvenlik hem de hesaplama verimliliği açısından literatüre önemli bir katkı olduğunu kanıtlamaktadır.

Keywords

• Ses şifreleme
• Ampirik Mod Ayrıştırma (EMD)
• Optimizasyon
• Kriptografik sinyal işleme

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