OrgACRN
/
sof
mirror of https://github.com/thesofproject/sof.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

Tools: Test: Audio: Replace the gaussian dither with triangular 

The gaussian (or other normal distribution shape) dither impacts
too much 16 bit signals. The triangular probability density
function (TDPF) is a sufficient compromise between added noise energy
and de-correlation of PCM samples.

This change improves for 48 kHz 16 bit audio measurement the THD+N
from -62.6 dB to -73.6 dB.

Signed-off-by: Seppo Ingalsuo <seppo.ingalsuo@linux.intel.com>
This commit is contained in:
Seppo Ingalsuo 2022-11-07 20:07:24 +02:00 committed by Liam Girdwood
parent 044d0b208d
commit 5471357792
1 changed files with 1 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
tools/test/audio/test_utils/dither_and_quantize.m
View File

@ -51,8 +51,7 @@ sx = size(x);
nx = sx(1);
nch = sx(2);
xq = int32(floor( scale*x + randn(nx,nch) - randn(nx,nch) -0.5)); % TPDF dither
%xq = int32(round( scale*x )); % Omit dither
xq = int32(round(scale * x + rand(nx,nch) + rand(nx, nch) - 1)); % TPDF dither
idx = find(xq > smax);
xq(idx) = smax;
idx = find(xq < smin);