compare -metric NCC looks like RMSE... it's not NCC

[toto-firestone]

ImageMagick version

6.9.13-34

Operating system

Linux

Operating system, version and so on

xubuntu 20.04.5 LTS

Description

• my compiled compare command
  compare --version
  Version: ImageMagick 6.9.13-34 (Beta) Q16-HDRI x86_64 d93d2ef:20251026 https://legacy.imagemagick.org
  Copyright: (C) 1999 ImageMagick Studio LLC
  License: https://imagemagick.org/script/license.php
  Features: Cipher DPC HDRI Modules
  Delegates (built-in): bzlib djvu fftw jbig jng jpeg ltdl lzma png tiff x xml zlib

• the output of NCC test
  compare -metric NCC /tmp/map-idle-check.png firestone/fstonebash/templates/map-idle-notif.png null:
  32767.5 (0.5)

• the output of RMSE test
  compare -metric RMSE /tmp/map-idle-check.png firestone/fstonebash/templates/map-idle-notif.png null:
  34990.2 (0.533916)

• the real NCC test (worked on my old computer, same xubuntu, but security repository worked fine and don't need to recompile because now it's broken) should be 1 float number ranging from 0 to 1

right now i checkout an older release and try again...

Steps to Reproduce

compare 2 images with latest version and NCC metric

Images

[toto-firestone]

compiling ImageMagick 6.9.10-23 solved the issue