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pdf.js (PDF preview) font rendering is sometimes ugly




PDF Viewer
4 years ago
3 years ago


(Reporter: Vincent Lefevre, Unassigned)


27 Branch

Firefox Tracking Flags

(Not tracked)


(Whiteboard: [pdfjs-c-rendering][pdfjs-d-font-linux], URL)


(1 attachment)



4 years ago
Created attachment 821030 [details]

Font rendering done by Mozilla's internal PDF viewer (pdf.js) is sometimes ugly.

Note that the status of "Allow pages to choose their own fonts..." doesn't matter. This is *not* bug 738627 (which is fixed in this version, BTW).

For instance, the problem can be seen on:

I've attached a part of a screenshot on page 3, obtained with Iceweasel 24 (Debian/unstable). But the same problem occurs with Nightly 27.0a1 (2013-10-23).

External PDF viewers Evince and xpdf do not have any problem on this PDF file.

My Debian bug report:


4 years ago
Priority: -- → P4
Whiteboard: [pdfjs-c-rendering][pdfjs-d-font-linux]
Mozilla/5.0 (X11; Linux x86_64; rv:27.0) Gecko/20100101 Firefox/27.0
I couldn't reproduce the issue on latest Aurora (20131118004001).

Do you have hardware acceleration enabled? Thank you
Flags: needinfo?(vincent-moz)

Comment 2

4 years ago
Here's what about:support gives me for Graphics:

Adapter Description	nouveau -- Gallium 0.4 on NV98
Device ID	Gallium 0.4 on NV98
Driver Version	3.0 Mesa 9.2.2
GPU Accelerated Windows	0/1 Basic
Vendor ID	nouveau
WebGL Renderer	nouveau -- Gallium 0.4 on NV98
windowLayerManagerRemote	false
AzureCanvasBackend	cairo
AzureContentBackend	none
AzureFallbackCanvasBackend	none

(I'm currently using Debian's Iceweasel 24.1.0, where I can reproduce the bug.)
Flags: needinfo?(vincent-moz)
Also reproduced using Firefox 25 on WinXP with HWA disabled (blocked due to driver version).
Looks like the font selection is incorrect, so the (wrong) selected font is stretched badly.
Ever confirmed: true
OS: Linux → All
Hardware: x86_64 → All
Reproduced with the latest PDF.js add-on (0.8.713).

Comment 5

4 years ago
I have the same problem on FF 25.0.1 viewing the same pdf on two Windows 7 x64 systems. The older system has a Radeon X600 graphics card with the Microsoft-supplied drivers, and has an ugly display. The other uses the internal Intel HD graphics on the i3-2100 CPU and is fine. gfx.direct2d.disabled is false on both FF's.

Comment 6

4 years ago
The same on FF esr 24.2.0 with Win XP et 7. It's ok with Chrome or FF+Acrobat Reader.
I just understand that this new feature is buggy at first but why change the pdf reader by default during installation of FF 24??

Comment 7

4 years ago
The same with Firefox Nightly (firefox-29.0a1.en-US.win32.installer.exe)
(In reply to Thomas Blohorn from comment #6)
> I just understand that this new feature is buggy at first but why change the
> pdf reader by default during installation of FF 24??

Thomas, on latest Firefox versions, this pref is set by default (see Options -> Applications: Portable Document Format (PDF) - Preview in Firefox) and can be changed.
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