Hi crackwitz,
I print the information of -.exr:
$ identify -verbose -.exr
Image: -.exr
Format: EXR (High Dynamic-range (HDR))
Class: DirectClass
Geometry: 4288x2412+0+0
Units: Undefined
Colorspace: RGB
Type: TrueColorAlpha
Base type: Undefined
Endianess: Undefined
Depth: 16-bit
Channel depth:
red: 16-bit
green: 16-bit
blue: 16-bit
alpha: 1-bit
Channel statistics:
Pixels: 10342656
Red:
min: 0 (0)
max: 65535 (1)
mean: 27428.7 (0.418535)
standard deviation: 20484.1 (0.312568)
kurtosis: -0.721404
skewness: 0.894195
entropy: 0.82117
Green:
min: 0 (0)
max: 65535 (1)
mean: 34510.8 (0.526601)
standard deviation: 20908 (0.319035)
kurtosis: -1.19547
skewness: 0.471033
entropy: 0.70769
Blue:
min: 71 (0.00108339)
max: 65535 (1)
mean: 45589.1 (0.695645)
standard deviation: 18410 (0.280919)
kurtosis: 0.000131018
skewness: -0.788791
entropy: 0.623624
Alpha:
min: 65535 (1)
max: 65535 (1)
mean: 65535 (1)
standard deviation: -nan (-nan)
kurtosis: -1.61532e+58
skewness: 1.32891e+41
entropy: 0
Image statistics:
Overall:
min: 0 (0)
max: 65535 (1)
mean: 43265.9 (0.660195)
standard deviation: -nan (-nan)
kurtosis: -1.4721
skewness: -0.341945
entropy: 0.538121
Rendering intent: Undefined
Gamma: 1
Background color: rgba(255,255,255,1)
Border color: rgba(223,223,223,1)
Matte color: rgba(189,189,189,1)
Transparent color: rgba(0,0,0,0)
Interlace: None
Intensity: Undefined
Compose: Over
Page geometry: 4288x2412+0+0
Dispose: Undefined
Iterations: 0
Compression: Undefined
Orientation: Undefined
Properties:
date:create: 2022-09-21T19:08:26+08:00
date:modify: 2022-09-21T19:08:26+08:00
signature: dff017f48502e894aadb188b9ada4fe1cc5316858de1eb3e7b41c2688f6253a4
Artifacts:
filename: -.exr
verbose: true
Tainted: False
Filesize: 32.2277MiB
Number pixels: 10.3427M
Pixels per second: 44.9681MB
User time: 0.230u
Elapsed time: 0:01.230
Version: ImageMagick 6.9.10-23 Q16 x86_64 20190101 https://imagemagick.org
It seems that the image statistics don’t contain negative values 