Assert in stereo_dft_generate_comfort_noise_fx in BASOP decoder with LTV MASA input with dtx and rate switching

Basic info

• Float reference:
  • Encoder (float): 5067d70d
  • Decoder (float):
• Fixed point:
  • Encoder (fixed): 492e1181
  • Decoder (fixed): 492e1181

Bug description

There is an assert in frame 3536 of BASOP decoder when fed with bitstream generated with BASOP or float encoder. There is DTX and rate switching involved and BW limitation might play some role. Below is the stack trace:

Ways to reproduce

Use these command lines with BASOP or float encoder, and decode with BASOP decoder. The assert happens in the decoder.

The rate switching pattern is here generic_start_128k_20frames.bin

IVAS_cod -masa 2 ltv48_MASA2TC.met -max_band wb -dtx generic_start_128k_20frames.bin 48 ltv48_MASA2TC.wav test_0067.bs
IVAS_dec EXT 48 test_0067.bs 0067_ltv48_MASA2TC.wav_generic_start_128k_20frames_48-48___EXT.wav