net.java.sip.communicator.impl.media.codec.audio.g729
Class Gainpred

java.lang.Object
  net.java.sip.communicator.impl.media.codec.audio.g729.Gainpred

 class Gainpred
extends Object

Author:

Lubomir Marinov (translation of ITU-T C source code to Java)

Constructor Summary

Gainpred()

Method Summary

(package private) static float	gain_predict(float[] past_qua_en, float[] code, int l_subfr) MA prediction is performed on the innovation energy (in dB with mean removed).
(package private) static void	gain_update_erasure(float[] past_qua_en) Update table of past quantized energies (frame erasure).
(package private) static void	gain_update(float[] past_qua_en, float g_code) Update table of past quantized energies.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Gainpred

Gainpred()

Method Detail

gain_predict

static float gain_predict(float[] past_qua_en,
                          float[] code,
                          int l_subfr)

MA prediction is performed on the innovation energy (in dB with mean removed).

Parameters:

past_qua_en - (i) :Past quantized energies

code - (i) :Innovative vector.

l_subfr - (i) :Subframe length.

Returns:

Predicted codebook gain

gain_update

static void gain_update(float[] past_qua_en,
                        float g_code)

Update table of past quantized energies.

Parameters:

past_qua_en - input/output :Past quantized energies

g_code - input: gbk1[indice1][1]+gbk2[indice2][1]

gain_update_erasure

static void gain_update_erasure(float[] past_qua_en)

Update table of past quantized energies (frame erasure).

     av_pred_en = 0.0;                                                     
     for (i = 0; i < 4; i++)                                               
        av_pred_en += past_qua_en[i];                                      
     av_pred_en = av_pred_en*0.25 - 4.0;                                   
     if (av_pred_en < -14.0) av_pred_en = -14.0; 
 

Parameters:

past_qua_en - input/output:Past quantized energies