update to 7.0.9-2 changes PNG size bigger

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update to 7.0.9-2 changes PNG size bigger

Post by taxen »


I just updated from 7.0.8-23-Q16 to 7.0.9-2-Q16 on Windows, both using x64-dll version.
Upon the update, I noticed that there is significant size change in processed PNG files from PDF.
Here is my command to make PNG from PDF

Code: Select all

magick -quiet -density 576 (PDF) -transparent white -alpha off -depth 3 -resize 25% (PNG)
With this, when used 7.0.8-23-Q16, I got 557KB PNG file.
Now, using 7.0.9-2-Q16, I got 1.22MB PNG file from the same PDF (https://www.jma.go.jp/jp/metcht/pdf/kos ... 578_12.pdf).
This is more than x2.25 bigger in size.

For other PDF files (links listed in https://www.jma.go.jp/jp/metcht/kosou.html), the results are mostly similar. The new version PNGs are all larger than the old ones, ranging from x1.076 to x 1.045. The one above mentioned is exceptionally big.

Is this result anticipated due to updates?
In my naked eyes, there seems no difference between the new and the old PNGs. If quality does not improve as size does, I prefer the old on because size matters for daily usage.