Commit b1164c83 authored by Jan Kiene's avatar Jan Kiene
Browse files

add proposed fix for correct power spec scaling

parent 9af190bf

lib_com/options.h

+1 −0
Original line number Diff line number Diff line
@@ -188,6 +188,7 @@ 
#define FIX_1139_REV_COLORATION_SHORT_T60               /* Nokia,FhG: Fix issue 1139, prevent sound coloration artefacts at very low reverberation times */

#define NONBE_FIX_1208_DFT_STEREO_PLC_BURST             /* Ericsson: Issue 1208, fix for overflow of sample offset counter for burst error in DFT Stereo PLC. */

#define FIX_1206_ZERO_OUT_IMDCT_BUFFERS_FOR_MCT_IGNORE  /* FhG: zero out all relevant imdct buffers in MCT decoding of channels with mct_chan_mode == MCT_CHAN_MODE_IGNORE */

#define NONBE_FIX_1204_MDCT_STEREO_NOISE_EST_SCALING



/* ##################### End NON-BE switches ########################### */

lib_dec/ivas_stereo_mdct_core_dec.c

+13 −0
Original line number Diff line number Diff line
@@ -620,14 +620,27 @@ static void run_min_stats( 
               computed only once (for ch == 0) and not again in the second run sive the outcome will be the same anyway */

            if ( ( will_estimate_noise_on_channel[0] == will_estimate_noise_on_channel[1] ) || ch == 0 )

            {

#ifdef NONBE_FIX_1204_MDCT_STEREO_NOISE_EST_SCALING

                float power_spec_scale_fac;



                /* calculate power spectrum from MDCT coefficients and estimated MDST coeffs */

                power_spec_scale_fac = 1.f / (float) ( L_FRAME16k * L_FRAME16k );

                power_spec[0] = spec_in[0] * spec_in[0] * power_spec_scale_fac;

                power_spec[L_FRAME16k - 1] = spec_in[L_FRAME16k - 1] * spec_in[L_FRAME16k - 1] * power_spec_scale_fac;

#else

                /* calculate power spectrum from MDCT coefficients and estimated MDST coeffs */

                power_spec[0] = spec_in[0] * spec_in[0];

                power_spec[L_FRAME16k - 1] = spec_in[L_FRAME16k - 1] * spec_in[L_FRAME16k - 1];

#endif

                for ( int16_t i = 1; i < L_FRAME16k - 1; i++ )

                {

                    float mdst;

                    mdst = spec_in[i + 1] - spec_in[i - 1];

#ifdef NONBE_FIX_1204_MDCT_STEREO_NOISE_EST_SCALING

                    power_spec[i] = power_spec_scale_fac * ( spec_in[i] * spec_in[i] + mdst * mdst );

#else

                    power_spec[i] = spec_in[i] * spec_in[i] + mdst * mdst;

#endif

                }

            }