On Fri, 15 Feb 2019 07:56:31 +0100
Lutz Haseloff <lutz.hasel...@toppkieker.info> wrote:
> First i tried the grph-downsample.lua script.
> Unfortunately i get an error message
> grph-downsample.lua:31: bad argument #2 to 'format' (number has no
> integer representation) See attached log file.
I remember that error. The script worked up to a particular context
version. I believe a Lua upgrade broke it. The version attached
should work.
Marco
if not modules then modules = { } end modules ['t-downsample'] = {
version = 1.001,
comment = "companion to grph-inc.mkiv",
author = "Peter Münster",
copyright = "PRAGMA ADE / ConTeXt Development Team",
license = "see context related readme files"
}
local format = string.format
-- figures.cachepaths.path = "cache" -- should be setup-option
local function sample_down(oldname, newname, resolution)
local request = figures.current().request
local width = request.width
local height = request.height
if resolution == "" or (not width and not height) then
print(format("Nothing to do: %s, %s, %s", oldname, newname, resolution))
return
end
local inch = 72.27
local image = img.scan{filename = oldname}
local xy = image.xsize / image.ysize
if not width then
width = height * xy / 65536
end
if not height then
height = width / xy / 65536
end
local xsize = resolution * width / inch
local ysize = resolution * height / inch
if xsize < image.xsize or ysize < image.ysize then
local s = format("gm convert -strip -resize %dx%d %s %s",
xsize, ysize, oldname, newname)
print("Conversion: " .. s)
os.execute(s)
else
print(format("Nothing to do: %s, %s, %s", oldname, newname, resolution))
print(format("xsize = %d, ysize = %d", xsize, ysize))
end
end
local formats = {"png", "jpg", "gif"}
for _, s in ipairs(formats) do
figures.converters[s] = figures.converters[s] or {}
figures.converters[s]["lowres." .. s] = sample_down
end
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