https://bugs.documentfoundation.org/show_bug.cgi?id=114532
--- Comment #26 from Tomaz Vajngerl <[email protected]> --- So IMHO we should store both WebP and PNG in the document. The reason is that after we decide that WebP has been supported in enough LO versions, we can just turn off saving the additional PNG fallback. Any documents that were created in the mean time with the WebP images will be able to remove the fallback PNG after this with just re-saving the file. One thing we need to remember is that WebP on the web is mostly used to super-compress the images to save bandwidth, so the images will mostly be using the lossy part of WebP. So if we convert such an image to PNG the size will increase significantly, so storing the original WebP in addition is insignificant compared to the overall size of PNG. I did a test - a 24MP photo compressed to 80% WebP was giving me 2.6MB. Convert that to PNG at compression level 9 resulted in 33.7MB and it took a looong time to compress. Reducing the compression level to a more typical 5 gave me 35.8MB. So the PNG vs. PNG + WebP is not even 10% increase in size and the size of WebP is similar to the difference between the PNG compression levels. There is another thing we can do and instead PNG use JPEG in such cases (Lossy WebP), so we would keep WebP and use JPEG for the fallback when opening in the older versions of LibreOffice. JPEG at 80,85,90 is giving me 4MB/5MB/6.6MB, which combined with the original WebP is still less than 1/3 of the PNG. -- You are receiving this mail because: You are the assignee for the bug.
