set the file type parameter after reading the image

imagemagick, when reading an image, sets its magick parameter to
indicate the file type, overriding the explicitly set file type for
output if it is set at creation.

as a result, previously (with graphicsmagick-libmagick-dev-compat
1.3.18-1 providing Image::Magick), svg output files were not png,
neither svg, but mvg (imagemagick vector graphics).

diff --git a/IkiWiki/Plugin/img.pm b/IkiWiki/Plugin/img.pm
index b92e24cc06fb93d8d88adcf1517903e46e49dc25..c861d707527df787de6224a82704a7805a576568 100644 (file)
--- a/IkiWiki/Plugin/img.pm
+++ b/IkiWiki/Plugin/img.pm
@@ -68,7 +68,7 @@ sub preprocess (@) {
 
        eval q{use Image::Magick};
        error gettext("Image::Magick is not installed") if $@;
-       my $im = Image::Magick->new($issvg ? (magick => "png") : ());
+       my $im = Image::Magick->new();
        my $imglink;
        my $r = $im->Read($srcfile);
        error sprintf(gettext("failed to read %s: %s"), $file, $r) if $r;
@@ -124,6 +124,7 @@ sub preprocess (@) {
                                # don't actually write resized file in preview mode;
                                # rely on width and height settings
                                if (! $params{preview}) {
+                                       $im->set($issvg ? (magick => 'png') : ());
                                        my @blob = $im->ImageToBlob();
                                        writefile($imglink, $config{destdir}, $blob[0], 1);
                                }