Re: RGB colorspace question

Bob Friesenhahn <[email protected]> Tue, 09 Jan 2024 07:33:30 -0600
Newsgroups gmane.comp.video.graphicsmagick.help
Message-ID <[email protected]>
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Thanks for investigating this issue!

Bob

=E2=81=A3Sent from BlueMail =E2=
=80=8B

On Jan 9, 2024, 7:21=E2=80=AFAM, at 7:21=E2=80=AFAM, Michael Orlitz=
ky <michael@orlitzky=2Ecom> wrote:
>On Mon, 2024-01-08 at 15:44 -0600, Bob =
Friesenhahn wrote:
>> 
>> Besides colorspace transformation, there is also =
the possibility of a
>
>> gamma adjustment=2E  A gamma adjustment will also=
 cause a change in 
>> numeric levels=2E
>> 
>
>Hm=2E I'm still not sure wh=
at the problem is, but I now have a minimal
>reproducer showing that ImageM=
agick is to blame:
>
>1=2E Create a single-pixel image with color #e1cbe1
>=
2=2E Save it as a BMP without colorspace information
>3=2E Run the convert =
commands
>4=2E GM has it as #E1CBE1, while IM has it as #C098C0
>
>So, not =
your problem=2E Thanks for the help=2E
>
>
>
>_____________________________=
__________________
>Graphicsmagick-help mailing list
>Graphicsmagick-help@l=
ists=2Esourceforge=2Enet
>https://lists=2Esourceforge=2Enet/lists/listinfo/=
graphicsmagick-help

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<html><head></head><body style=3D"zoom: 0%;"><div dir=3D"auto">Thanks for i=
nvestigating this issue!<br><br></div>
<div dir=3D"auto">Bob<br><br></div>
=
<div dir=3D"auto"><!-- tmjah_g_1299s -->Sent from <!-- tmjah_g_1299e --><a =
href=3D"https://bluemail=2Eme"><!-- tmjah_g_1299s -->BlueMail<!-- tmjah_g_1=
299e --></a><!-- tmjah_g_1299s --> <!-- tmjah_g_1299e --></div>
<div class=
=3D"gmail_quote" >On Jan 9, 2024, at 7:21=E2=80=AFAM, Michael Orlitzky &lt;=
<a href=3D"mailto:michael@orlitzky=2Ecom" target=3D"_blank">michael@orlitzk=
y=2Ecom</a>&gt; wrote:<blockquote class=3D"gmail_quote" style=3D"margin: 0p=
t 0pt 0pt 0=2E8ex; border-left: 1px solid rgb(204, 204, 204); padding-left:=
 1ex;">
<pre class=3D"blue">On Mon, 2024-01-08 at 15:44 -0600, Bob Friesenh=
ahn wrote:<br><blockquote class=3D"gmail_quote" style=3D"margin: 0pt 0pt 1e=
x 0=2E8ex; border-left: 1px solid #729fcf; padding-left: 1ex;"> <br> Beside=
s colorspace transformation, there is also the possibility of a <br> gamma =
adjustment=2E  A gamma adjustment will also cause a change in <br> numeric =
levels=2E<br> <br></blockquote><br>Hm=2E I'm still not sure what the proble=
m is, but I now have a minimal<br>reproducer showing that ImageMagick is to=
 blame:<br><br>1=2E Create a single-pixel image with color #e1cbe1<br>2=2E =
Save it as a BMP without colorspace information<br>3=2E Run the convert com=
mands<br>4=2E GM has it as #E1CBE1, while IM has it as #C098C0<br><br>So, n=
ot your problem=2E Thanks for the help=2E<br><br><br><br><hr><br>Graphicsma=
gick-help mailing list<br>Graphicsmagick-help@lists=2Esourceforge=2Enet<br>=
<a href=3D"https://lists=2Esourceforge=2Enet/lists/listinfo/graphicsmagick-=
help">https://lists=2Esourceforge=2Enet/lists/listinfo/graphicsmagick-help<=
/a><br></pre></blockquote></div></body></html>
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