Synthesis saturates for stereo with dtx and bitrate switching

Basic info

  • Commit SHA: f9549819
  • Platform: msvc, linux

Bug description

With as specific combination of low energy signal, dtx and bitrate switching the decoded synthesis can "explode", causing a severe artifact. The problem is present in float and fixed point

below :

  • Original (stereo)
  • float-float synthesis
  • core_brate
  • element_brate
  • element_mode
  • L_frame

image.png

image.png

Ways to reproduce

(Clear steps or refer to a failing automated test, e.g. with a pipeline link)

IVAS_cod -stereo -dtx switchPaths/sw_13k2_to_128k_10fr.bin 48 in_stm10.wav bit.bin

IVAS_dec stereo 48 bit.bin decoded.flt.wav

The input file can be provided upon request.