Renderer Binaural output at 16khz for main-pc branch is 6 dB louder compare to main or float-pc branch

Basic info

• Float reference: float-pc
  • Encoder (float): c10fcf4e
  • Decoder (float):c10fcf4e
• Fixed point: main-pc
  • Encoder (fixed): 8a7bc3f3
  • Decoder (fixed): 8a7bc3f3
• Fixed point: main
  • Encoder (fixed): 4cdfe14b
  • Decoder (fixed):4cdfe14b

Bug description

Renderer Binaural output at 16khz for main-pc branch is 6 dB louder compare to main or float-pc branch. Run hereunder command for the different branch

output for main :

output for float-pc :

output for main-pc:

It seems to be related to following code :

in renderer.c file file at line 1610 :

    outBuffer.pq_fact = &outBuffer.q_factor;
    Word16 subframe_len = (Word16) ( args.sampleRate / ( 200 ) ); // sample rate /FRAMES_PER_SEC * MAX_PARAM_SPATIAL_SUBFRAMES
    Word16 gd_bits = find_guard_bits( subframe_len );
Then line 1636

        *outBuffer.pq_fact = 16 - ( gd_bits ); (gd_bits = 7 at 16kHz, 8 at 32kHz and 48kHz )

The output scaling factor seems to depend on value of subframe_len.

Ways to reproduce

stv714MC16c.wav.zip

IVAS_rend -i stv714MC16c.wav -if 7_1_4 -o rend_out_714_hrir_16khz.wav -of BINAURAL -fs 16