Am 15. Februar 2019 11:08:45 MEZ schrieb Marco Patzer <lists@homerow.info>:

On Fri, 15 Feb 2019 10:22:48 +0100
Lutz Haseloff <lutz.haseloff@toppkieker.info> wrote:

but both scripts trow the same error on windows and linux-armhf:

grph-downsample.lua:32: bad argument #2 to 'format' (number has no
integer representation)

It works here on linux-armhf. No Lua error. Maybe the file got
mangled during transmission.

I've uploaded a modified version to github, maybe try that one:

  https://github.com/mpfusion/context-downsample

It includes a wrapper so you can call it like any other module
(\usemodule[downsample]). It's still Peter's code, but with small
modifications, so it degrades jpg as well as png images at the same
time. It's a quick hack, but works here, also on armhf.

Marco