poor type 1c font rendering
Submitted by Germán Poo-Caamaño
Assigned to poppler-bugs
Link to original bug (#100869)
Description
Created attachment 131121 PDF Test case
This was reported in https://bugzilla.gnome.org/show_bug.cgi?id=776924
The following pdf document is being rendered rather ugly in evince:
http://www.scottaaronson.com/papers/pnp.pdf
All fonts are embedded. They're all type 1c fonts.
$ pdffonts pnp.pdf name type encoding emb sub uni object ID
VXEZKP+CMSS17 Type 1C Builtin yes yes no 4 0 YDPTNV+CMR12 Type 1C Builtin yes yes no 5 0 JLCEZQ+CMR17 Type 1C Builtin yes yes no 6 0 NUVJJI+CMSY8 Type 1C Builtin yes yes yes 7 0 VBIHCP+CMBX10 Type 1C Builtin yes yes no 8 0 CXZLTS+CMR10 Type 1C Builtin yes yes yes 9 0 JGIYMZ+CMSS10 Type 1C Builtin yes yes yes 10 0 AGGZPP+CMR7 Type 1C Builtin yes yes no 11 0 RGQKMS+CMSY10 Type 1C Builtin yes yes yes 12 0 BYIFKE+CMBX12 Type 1C Builtin yes yes no 13 0 FNGYIT+CMR8 Type 1C Builtin yes yes yes 15 0 JFBFYB+CMSY6 Type 1C Builtin yes yes yes 32 0 OBXTKK+CMR9 Type 1C Builtin yes yes yes 33 0 GVHKBA+CMTI10 Type 1C Builtin yes yes no 87 0 RVPORJ+CMMI10 Type 1C Builtin yes yes yes 89 0 JKFOWN+CMSS12 Type 1C Builtin yes yes no 93 0 KIISBX+CMR6 Type 1C Builtin yes yes yes 99 0 WWJJES+CMMI9 Type 1C Builtin yes yes yes 100 0 DRXVBH+CMSS9 Type 1C Builtin yes yes no 101 0 IWKPFB+CMMI8 Type 1C Builtin yes yes yes 106 0 IYGFKD+CMMI6 Type 1C Builtin yes yes yes 110 0 SGXEVV+CMTI9 Type 1C Builtin yes yes no 129 0 DNNGNS+CMEX9 Type 1C Builtin yes yes yes 131 0 FPKZIJ+CMSY9 Type 1C Builtin yes yes yes 132 0 DOOAXC+CMSS8 Type 1C Builtin yes yes no 170 0 OLTLXQ+CMCSC10 Type 1C Builtin yes yes no 179 0 JXRWPD+CMEX10 Type 1C Builtin yes yes yes 188 0 KSYIAZ+CMEX7 Type 1C Builtin yes yes no 224 0 UROALT+CMMI5 Type 1C Builtin yes yes no 228 0 SKNWGA+MSBM10 Type 1C Builtin yes yes yes 239 0 PFOPPM+CMSY5 Type 1C Builtin yes yes no 310 0 EFHBMR+CMR5 Type 1C Builtin yes yes no 311 0 PLAHEP+CMEX8 Type 1C Builtin yes yes no 690 0 UEHLMU+MSBM7 Type 1C Builtin yes yes no 852 0
I wonder how the embedded pdf viewer of firefox can do a better job with this document than evince. Most other pdf documents look better in evince.
By ugly the reporter means:
So here are a couple of screenshots. As you can see evince has the lowest font rendering quality, because it's blurry and the stroke width is not concise (especially when it comes to the equal sign in the headline).
The font rendering of the internal pdf viewer of firefox also suffers from being blurry, but at least the stroke width is more concise.
I also added some screenshots taken under macOS. They are not blurry, but the resolution is also much higher. So it's more like a reference. Comparing evince's font rendering in the pdf with the font rendering in the outline window on the left, you can see that it is very well possible to get a better result with the lower linux resolution.
And it's not like I was searching for a zoom factor where evince has problems. Sure, the quality might improve with other zoom factors, but it also declines with others as well. In the end the zoom factor cannot "fix" the font rendering quality; the font rendering is still clearly better in firefox when "optimizing" the zoom factor in both applications.
Attachment 131121, "PDF Test case":
pnp.pdf