Author: kmalaussene Date: Thu Feb 19 03:25:35 2009 New Revision: 4084 Log: Extract function ff_apply_gain_ctrl that could be reused by the QCELP decoder and other celp codecs. Modified: amr/amrnbfloatdec.c Modified: amr/amrnbfloatdec.c ============================================================================== --- amr/amrnbfloatdec.c Wed Feb 18 01:28:12 2009 (r4083) +++ amr/amrnbfloatdec.c Thu Feb 19 03:25:35 2009 (r4084) @@ -95,6 +95,35 @@ static void weighted_vector_sumf(float * + weight_coeff_b * in_b[i]; } +/** + * @note this function should be moved to acelp_vectors.[ch] + * and used in qcelpdec.c + * + * Apply adaptive gain control by gain scaling. + * + * @param v_out output vector + * @param v_in gain-controlled vector + * @param v_ref vector to control gain of + * @param length vectors length + * + * FIXME: If v_ref is a zero vector, it energy is zero + * and the behavior of the gain control is + * undefined in the specs. + * + * TIA/EIA/IS-733 2.4.8.3-2/3/4/5, 2.4.8.6 + */ +void ff_apply_gain_ctrl(float *v_out, const float *v_ref, const float *v_in, const int length) +{ + int i; + float scalefactor = ff_dot_productf(v_in, v_in, length); + if(scalefactor) + scalefactor = sqrt(ff_dot_productf(v_ref, v_ref, length) / scalefactor); + else + ff_log_missing_feature(NULL, "Zero energy for gain control", 1); + for(i=0; i<length; i++) + v_out[i] = scalefactor * v_in[i]; +} + static void reset_state(AMRContext *p) { int i; @@ -806,21 +835,14 @@ static int synthesis(AMRContext *p, floa if(p->pitch_gain[4] > 0.5 && !overflow) { float excitation_temp[AMR_SUBFRAME_SIZE]; float pitch_factor = (p->cur_frame_mode == MODE_122 ? 0.25 : 0.5)*p->beta*p->pitch_gain[4]; - float eta, temp1 = 0.0, temp2 = 0.0; for(i=0; i<AMR_SUBFRAME_SIZE; i++) { // emphasize pitch vector contribution excitation_temp[i] = excitation[i] + pitch_factor*p->pitch_vector[i]; - // find gain scale - temp1 += excitation[i]*excitation[i]; - temp2 += excitation_temp[i]*excitation_temp[i]; } // adaptive gain control by gain scaling - eta = sqrt(temp1/temp2); - for(i=0; i<AMR_SUBFRAME_SIZE; i++) { - excitation[i] = eta*excitation_temp[i]; - } + ff_apply_gain_ctrl(excitation, excitation, excitation_temp, AMR_SUBFRAME_SIZE); } for(i=0; i<AMR_SUBFRAME_SIZE; i++) {