Assert in ivas_fill_spectrum_fx of BASOP decoder when fed with OMASA bitstream from BASOP encoder

Basic info

• Fixed point:
  • Encoder (fixed): ccb4b561
  • Decoder (fixed): ccb4b561

Bug description

Using OMASA LTV input encoded with BASOP encoder, assert happens in BASOP decoder function ivas_fill_spectrum_fx at frame 4916.

Here is the stack trace:

Ways to reproduce

Use the OMASA LTV test vectors and following command lines. The assert happens in decoder.

IVAS_cod -ism_masa 3 1 ltv48_OMASA_3ISM_1TC_ISM1.csv ltv48_OMASA_3ISM_1TC_ISM2.csv ltv48_OMASA_3ISM_1TC_ISM3.csv ltv48_OMASA_3ISM_1TC.met -max_band swb  128000 48 ltv48_OMASA_3ISM_1TC.wav test_0235.bs
IVAS_dec MONO 48 test_0235.bs 0235_ltv48_OMASA_3ISM_1TC.wav_128k_48-48___MONO.wav