Division by 0 in stereo_dft_dec_smooth_parameters_fx()
in c7ca9d3e, a division by zero can occur with the following bitstream :
Command line : IVAS_dec STEREO 32 M1stereo_-dtx_16400_32.bit syn
the issue happens in the function stereo_dft_dec_smooth_parameters_fx() at line 895 where STEREO_DFT_ITD_CNG_XFADE == hStereoDft->itd_xfade_counter.
The same issue seems present in the floating point decoder. @norvell, @multrus, @vaclav any idea if the latest floating encoder can still generate this kind of bitsteam? if yes, then both float and fixed decoder should be corrected.
hStereoDft->itd_xfade_step_fx = BASOP_Util_Divide3232_Scale(L_sub( hStereoDft->itd_xfade_target_fx, hStereoDft->itd_xfade_prev_fx) , L_shl(sub( STEREO_DFT_ITD_CNG_XFADE, hStereoDft->itd_xfade_counter ), **Q15), &q_val);`
Floating-point equivalent :
hStereoDft->itd_xfade_step = ( hStereoDft->itd_xfade_target - hStereoDft->itd_xfade_prev ) / ( STEREO_DFT_ITD_CNG_XFADE - hStereoDft->itd_xfade_counter );