A codec is a device which helps to encode or decode digital data signals, it encodes a data stream or encrypted form and a decoder operates a reverse process of encoder. This codec's are applied in signal editing, video editing; signal conferencing, video conferencing etc. The codec's have two major principles like pulse code modulation method and delta modulation method. In this paper, we proposed a survey of various effective codec implementation and performance analyzing methods with different applications. The various effective codec's are implemented such as CELP codec, MELP codec, SPEEX speech codec, and OPUS speech codec. A CELP codec is code excited linear prediction method which helps to increase bit detection rate, high efficient process in speech coding, and peak quality in low bit rates. A CELP codec is to be applied in real time advanced technologies such as automatic watermarking process, communication field, Zigbee applications, filtering process, power spectrum analyzing fields, quantization methods, Gaussian processing fields, ARM processors etc. A MELP is a mixed excitation liner prediction method which helps to eliminate the voicing error obtains in multiple state excitation method. A SPEEX method helps to analyze speech quality and bit rate and an OPUS is high flexible speech codec technique which plays a vital role in real time applications. These methods are implemented and performances are analyzed based on different real world applications.

A Survey of Various Effective Codec Implementation Methods with Different Real Time Applications

This paper proposes the unification of the codeexcited linear prediction (CELP) codec process with watermarking based on formant tuning. The serial problem in atermarking and then encoding with the CELP codec was thereby reduced by using the proposed method which also ncreased the bit detection rate. We took advantage of two key properties: I) humans do not perceive alterations applied to formants and II) CELP and watermarking based on formant tuning methods utilize lineal prediction coefficients. We investigated the inaudibility and robustness of the proposed method by carrying out three different experiments using log-spectrum distance (LSD), the perceptual evaluation of speech quality (PESQ) and the bit detection rate (BDR). The results indicated that the proposed method satisfied the inaudibility requirement when watermarking was applied to the CELP codec, which increased the watermarking detection rate.

Erick Christian Garcia Alvarez

Papers

An Automatic Watermarking in CELP Speech Codec Based on Formant Tuning