I am aware of the lossy format of JPEG that cause generation loss.The intermediate images unfortunately have to be JPEG in this case as Guetzli is too slow to be fed one whole image.What command & tool will you recommand to merge the JPEG tiles , applying as minimum compression as possible during the merge process.Ofcourse keeping in mind that there will be some lossfmw42 wrote: ↑2017-11-22T12:45:52-07:00P.S. If you, say, use -quality 80 to make the jpg images, then if you add -quality 100, you will get as close visual quality as you had before, but the file size will increase dramatically. So you probably want to make the new combined result have a similar or slightly larger quality than 80, but not 100. Each time you compress and decompress with JPG, you lose some visual quality. You cannot get that back. You would be better keeping your intermediate images in non-lossy compressed form, such as tif with lzw compression or png.
Questions and postings pertaining to the usage of ImageMagick regardless of the interface. This includes the command-line utilities, as well as the C and C++ APIs. Usage questions are like "How do I use ImageMagick to create drop shadows?".
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All depends upon whether you want the file size to increase or not. If you want the best quality after combining then use -quality 100. If you want about the same file size as all the JPG combined, then use the same -quality you used to create the JPG cropped images.What command & tool will you recommand to merge the JPEG tiles , applying as minimum compression as possible during the merge process.Ofcourse keeping in mind that there will be some loss