https://bugzilla.redhat.com/show_bug.cgi?id=2001332
Bug ID: 2001332
Summary: pango-view with --backend=ft2 and ---antialias=none
generates antialiased renderings
Product: Fedora
Version: 34
Hardware: x86_64
OS: Linux
Status: NEW
Component: pango
Severity: high
Assignee: [email protected]
Reporter: [email protected]
QA Contact: [email protected]
CC: [email protected],
[email protected],
[email protected],
[email protected], [email protected],
[email protected], [email protected],
[email protected], [email protected],
[email protected]
Target Milestone: ---
Classification: Fedora
Created attachment 1820649
--> https://bugzilla.redhat.com/attachment.cgi?id=1820649&action=edit
image showing the problem
Description of problem:
Hello Fedora Team,
I have a recently updated Fedora 34 installation.
The problem I want to report is that it looks like
the pango-view tool is always turning antialiasing on
when one uses the FreeType backend --backend=ft2,
even when one explicitly switches antialiasing off with --antialias=none,
whereas it works for the --backend=cairo option.
A second question would be if the FreeType backend
generally doesn't/can't support --antialias=none?
I tried to find some examples in C with antialising turned off
but I wasn't successful.
I must confess I didn't check other distributions.
As pango-view is regarded as a tool for creating minimal reproducers
against the font rendering stack, I dare to set the severity to 'high' :-)
Best Regards
Andre
Version-Release number of selected component (if applicable):
$ uname -a
Linux localhost.localdomain 5.13.13-200.fc34.x86_64 #1 SMP Thu Aug 26 17:06:39
UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
$ dnf list installed | grep dejavu
dejavu-lgc-sans-fonts.noarch 2.37-16.fc34
@fedora
dejavu-lgc-sans-mono-fonts.noarch 2.37-16.fc34
@fedora
dejavu-lgc-serif-fonts.noarch 2.37-16.fc34
@fedora
dejavu-sans-fonts.noarch 2.37-16.fc34
@fedora
dejavu-sans-mono-fonts.noarch 2.37-16.fc34
@fedora
dejavu-serif-fonts.noarch 2.37-16.fc34
@fedora
$ dnf list installed | grep ImageMagick
ImageMagick.x86_64 1:6.9.11.27-3.fc34
@fedora
ImageMagick-libs.x86_64 1:6.9.11.27-3.fc34
@fedora
$ dnf list installed | grep pango
pango.i686 1.48.9-2.fc34
@updates
pango.x86_64 1.48.9-2.fc34
@updates
pango-devel.x86_64 1.48.9-2.fc34
@updates
pangomm.x86_64 2.46.1-1.fc34
@updates
$ dnf list installed | grep freetype
freetype.i686 2.10.4-3.fc34
@fedora
freetype.x86_64 2.10.4-3.fc34
@fedora
freetype-devel.x86_64 2.10.4-3.fc34
@fedora
$ dnf list installed | grep fontconfig
fontconfig.i686 2.13.94-2.fc34
@updates
fontconfig.x86_64 2.13.94-2.fc34
@updates
fontconfig-devel.x86_64 2.13.94-2.fc34
@updates
$ dnf list installed | grep cairo
cairo.i686 1.17.4-3.fc34
@fedora
cairo.x86_64 1.17.4-3.fc34
@fedora
cairo-devel.x86_64 1.17.4-3.fc34
@fedora
cairo-gobject.i686 1.17.4-3.fc34
@fedora
cairo-gobject.x86_64 1.17.4-3.fc34
@fedora
cairomm.x86_64 1.14.2-8.fc34
@fedora
python2-cairo.x86_64 1.18.2-8.fc34
@fedora
python3-cairo.x86_64 1.20.0-2.fc34
@fedora
How reproducible:
Always
Steps to Reproduce:
$ pango-view --no-display --dpi=72 --backend=cairo --antialias=none
--font="DejaVu Sans 38" --text="ABCDEFGHIJKLMNOPQRSTUVWXYZ"
--output=abc-cairo-aa-none.png
$ pango-view --no-display --dpi=72 --backend=cairo --antialias=gray
--font="DejaVu Sans 38" --text="ABCDEFGHIJKLMNOPQRSTUVWXYZ"
--output=abc-cairo-aa-gray.png
$ pango-view --no-display --dpi=72 --backend=cairo --antialias=subpixel
--font="DejaVu Sans 38" --text="ABCDEFGHIJKLMNOPQRSTUVWXYZ"
--output=abc-cairo-aa-subpixel.png
$ pango-view --no-display --dpi=72 --backend=ft2 --antialias=none
--font="DejaVu Sans 38" --text="ABCDEFGHIJKLMNOPQRSTUVWXYZ"
--output=abc-ft2-aa-none.png
$ pango-view --no-display --dpi=72 --backend=ft2 --antialias=gray
--font="DejaVu Sans 38" --text="ABCDEFGHIJKLMNOPQRSTUVWXYZ"
--output=abc-ft2-aa-gray.png
$ pango-view --no-display --dpi=72 --backend=ft2 --antialias=subpixel
--font="DejaVu Sans 38" --text="ABCDEFGHIJKLMNOPQRSTUVWXYZ"
--output=abc-ft2-aa-subpixel.png
$ gimp abc-*.png
Actual results:
Attached pngs.
The file abc-ft2-aa-none.png is in gray-scale and not as expected in
black-white.
The file abc-cairo-aa-none.png is in black-white as expected.
Expected results:
I would have expected the files abc*--aa-none.png looking near identical.
Additional info:
--
You are receiving this mail because:
You are on the CC list for the bug.
_______________________________________________
fonts-bugs mailing list -- [email protected]
To unsubscribe send an email to [email protected]
Fedora Code of Conduct:
https://docs.fedoraproject.org/en-US/project/code-of-conduct/
List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines
List Archives:
https://lists.fedoraproject.org/archives/list/[email protected]
Do not reply to spam on the list, report it:
https://pagure.io/fedora-infrastructure
