- Use Lanczos everywhere (Mitchell really isn't that good for mipmap scaling)
- Use 1x1 subsampling everywhere (the discoloration just isn't worth it)
- Tone down to quality 87 to get the file sizes back down to almost-normal level.
Mainly tuned for fullscreen viewing (I haven't looked at thumbnails). About 8%
increased file size, it seems.
my $height = $img->Get('rows');
my ($nwidth, $nheight) = scale_aspect($width, $height, $xres, $yres);
- # Use lanczos (sharper) for heavy scaling, mitchell (faster) otherwise
- my $filter = 'Mitchell';
- my $quality = 90;
- my $sf = undef;
-
- if ($width / $nwidth > 8.0 || $height / $nheight > 8.0) {
- $filter = 'Lanczos';
- $quality = 85;
- $sf = "1x1";
- }
+ my $filter = 'Lanczos';
+ my $quality = 87;
+ my $sf = "1x1";
if ($xres != -1) {
$cimg->Resize(width=>$nwidth, height=>$nheight, filter=>$filter, 'sampling-factor'=>$sf);