MikeA Posted April 25, 2020 Share Posted April 25, 2020 In making a book of photographs to be printed by a print-on-demand company, I found I'd exceeded their 300 MB per PDF limit even before I had all image files placed in the Publisher document. The idea of further JPEG compression was not appealing but I decided (holding my nose the entire time) to try compression settings during export to PDF. The results surprised me. No compression: 388.5 MB No compression (2nd time around): 363.4 MB (why the difference?)Compression setting 100: 211 MB Compression setting 99: 182.7 MB Compression setting 97: 139 MB Compression setting 95: 114 MB Compression setting 90: 83 MB I take it this means that the max quality setting (100) still involves re-compression of the images. All along I'd thought 100 means: no compression. Apparently not. So if output file sizes are plaguing you, perhaps the slight JPEG compression will be helpful. Before starting the tests I ran the original JPEGs through the compression program JPEG-Mini. It made a whopping difference in the files' sizes and without noticeable loss of quality. But using the JPEGs compressed with JPEG-Mini as source files within the Publisher document doesn't seem to have provided a lot of savings during export to PDF. Perhaps JPEG-Mini's major advantage is a "web thing" and not a "print thing". Quote Affinity Publisher and Photo 1.8.3 (Windows). Lenovo laptop with decidedly sub-optimal monitor. At least it works.“The wonderful thing about standards is that you can have as many of ’em as you want.”– Anonymous cynic Link to comment Share on other sites More sharing options...
lacerto Posted April 26, 2020 Share Posted April 26, 2020 (...) MikeA 1 Quote Link to comment Share on other sites More sharing options...
MikeA Posted April 26, 2020 Author Share Posted April 26, 2020 I appreciate your taking the time to do all that. I made a note of most of the file sizes I obtained after doing some more of this (compatibility setting for all exports from Publisher: PDF 1.4): Files marked "[C]" were done with JPEG-Mini Pro compressed source files. Those marked "[F]" were not compressed via JPEG-Mini. The numbers within the filenames indicate compression level in Publisher export dialog. [F] 4/25/2020 19:36 387,526,265 Boise2018-NOCOMP.pdf [C] 4/25/2020 15:35 388,483,998 Boise2018_JPEG-NOcompr.pdf (unexpected result; export with uncompressed JPEGs is smaller, somehow) [F] 4/25/2020 19:39 244,546,273 Boise2018-Compr100.pdf [C] 4/25/2020 16:28 210,858,408 Boise2018_JPEGcompr-100.pdf [F] 4/25/2020 19:43 210,600,433 Boise2018-Compr99.pdf [C] 4/25/2020 16:23 182,725,987 Boise2018_JPEGcompr-99.pdf [F] 4/25/2020 19:46 173,309,855 Boise2018-Compr98.pdf With source files compressed with JPEG-Mini and a PDF compression setting of 90, the PDF's size dropped to ~83 MB. Switching for a couple of tests to PDF/X-1a:2003 produced crazy-large files and I gave up on that idea quick-like. In another discussion about this, someone mentioned using Acrobat to optimize his PDFs' sizes. That's an expensive solution for someone like me who isn't in the trade. Perhaps there's other software specialized for that purpose and without all of Acrobat's bells and whistles. Then again those kinds of tools might produce optimized files that aren't suitable for press. Quote Affinity Publisher and Photo 1.8.3 (Windows). Lenovo laptop with decidedly sub-optimal monitor. At least it works.“The wonderful thing about standards is that you can have as many of ’em as you want.”– Anonymous cynic Link to comment Share on other sites More sharing options...
lacerto Posted April 26, 2020 Share Posted April 26, 2020 (...) MikeA 1 Quote Link to comment Share on other sites More sharing options...
MikeA Posted April 26, 2020 Author Share Posted April 26, 2020 Thanks for the further information. If optimization could foul up the print job, I'll live without it. I just now uploaded the PDF to the on-demand book company and while it wasn't lightning-fast, it didn't give me fits. The export settings I used — PDF 1.4, downsampling on, JPEG compression=99 — produced a file just under the maximum allowed (300 MB). If I'd used the JPEG-mini files I could probably have added a few more images and used quality=100. But this is good enough for now. Well, assuming the book doesn't look like dog-meat-on-a-stick when they're done with it. : ) It's been a long haul learning Publisher from the ground up and acquainting myself with font-related tools I haven't had to think about for years. Thanks a lot for your advice along the way—it was extremely helpful. Quote Affinity Publisher and Photo 1.8.3 (Windows). Lenovo laptop with decidedly sub-optimal monitor. At least it works.“The wonderful thing about standards is that you can have as many of ’em as you want.”– Anonymous cynic Link to comment Share on other sites More sharing options...
R C-R Posted April 26, 2020 Share Posted April 26, 2020 9 hours ago, MikeA said: I take it this means that the max quality setting (100) still involves re-compression of the images. All along I'd thought 100 means: no compression. Apparently not. Yes, even at the maximum "quality" setting the standard JPEG discrete cosine transform (DCT) encoder uses a form of lossy compression. Quote All 3 1.10.8, & all 3 V2.4.1 Mac apps; 2020 iMac 27"; 3.8GHz i7, Radeon Pro 5700, 32GB RAM; macOS 10.15.7 Affinity Photo 1.10.8; Affinity Designer 1.108; & all 3 V2 apps for iPad; 6th Generation iPad 32 GB; Apple Pencil; iPadOS 15.7 Link to comment Share on other sites More sharing options...
MikeA Posted May 1, 2020 Author Share Posted May 1, 2020 On 4/26/2020 at 12:31 AM, Lagarto said: Here is a comparison of quality difference (original left and optimized right, at 300% zoom level): Interesting. Depending on my OCD level for the day, I'll think either that the differences are negligible or that they're very obvious. Then again 300% is a pretty extreme enlargement. Quote Affinity Publisher and Photo 1.8.3 (Windows). Lenovo laptop with decidedly sub-optimal monitor. At least it works.“The wonderful thing about standards is that you can have as many of ’em as you want.”– Anonymous cynic Link to comment Share on other sites More sharing options...
lacerto Posted May 2, 2020 Share Posted May 2, 2020 (...) Quote Link to comment Share on other sites More sharing options...
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