Use Cairo 1.16

[mrliptontea]

Hi,

First of all let me join #2 in saying thank you for this!

Secondly, there is a known bug in Cairo library: https://gitlab.freedesktop.org/cairo/cairo/-/issues/358, which for some PDFs can result in free(): invalid pointer error.

It's present in version 1.17.2 but not in 1.16. There's no later version than 1.17.2 at the moment (although the commit that enabled the bug has been since reverted), so I suggest using 1.16. It's also what's used on alpine linux package:

$ docker run --rm -i -t alpine:edge sh
/ # apk add poppler-utils
fetch https://dl-cdn.alpinelinux.org/alpine/edge/main/x86_64/APKINDEX.tar.gz
fetch https://dl-cdn.alpinelinux.org/alpine/edge/community/x86_64/APKINDEX.tar.gz
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[carasaffi]

Hi this issue seems to be there with font config. [code 127] pdftocairo: symbol lookup error: /opt/lib/libfontconfig.so.1: undefined symbol: FT_Done_MM_Var. Can you provide a fix for this?

[micronaut]

@carasaffi I was able to resolve the undefined symbol: FT_Done_MM_Var error by adding an environment variable to the Lamda function: LD_PRELOAD = /opt/lib/libfreetype.so.