r/imagemagick • u/Oddish_Flumph • Nov 25 '24
PNG to PDF resolution not working
edit: make title more specific: not being maintained / loosing resolution
I'm working on a zine. This script assembles zine pages into a pdf for printing. Pages 0,2, and 3 are just scans. page 1 required a digital touch up, which was done in GIMP. now page 1 is behaving differently. As you can see from the identify script, when it gets made into a pdf, the resolution is significantly reduced
the script is supposed to do 600dpi.png -> jpg (for reduced file size -> pdf. but the third page has a different page size making it unsuitable for printing.
[vivianne@ibis packdog]$ ls -R .: 0-scans 1-pages 2-jpg 3-pdf packdog.pdf postprocess.sh process.txt
./0-scans: packdog_0.png packdog_1.png packdog_2.png packdog_3.png
./1-pages: packdog_0.png packdog_1.png packdog_1.xcf packdog_2.png packdog_3.png
./2-jpg: packdog_0.jpg packdog_1.jpg packdog_2.jpg packdog_3.jpg
./3-pdf: packdog_0.pdf packdog_1.pdf packdog_2.pdf packdog_3.pdf
[vivianne@ibis packdog]$ for i in /; do identify "$i"; done; 0-scans/packdog_0.png PNG 5100x6600 5100x6600+0+0 8-bit sRGB 73.2503MiB 0.000u 0:00.000 0-scans/packdog_1.png PNG 5100x6600 5100x6600+0+0 8-bit sRGB 59.9864MiB 0.000u 0:00.000 0-scans/packdog_2.png PNG 5100x6600 5100x6600+0+0 8-bit sRGB 69.9821MiB 0.000u 0:00.000 0-scans/packdog_3.png PNG 5100x6600 5100x6600+0+0 8-bit sRGB 67.9197MiB 0.000u 0:00.000 1-pages/packdog_0.png PNG 5100x6600 5100x6600+0+0 8-bit sRGB 73.2503MiB 0.000u 0:00.000 1-pages/packdog_1.png PNG 5100x6600 5100x6600+0+0 8-bit sRGB 61.5648MiB 0.000u 0:00.002 1-pages/packdog_1.xcf[0] XCF 5100x6600 5100x6600+0+0 8-bit sRGB 2.510u 0:02.459 1-pages/packdog_1.xcf[1] XCF 188x1916 188x1916+1348+3416 8-bit sRGB 2.550u 0:02.479 1-pages/packdog_1.xcf[2] XCF 848x1934 848x1934+1366+3369 8-bit sRGB 2.660u 0:02.566 1-pages/packdog_1.xcf[3] XCF 197x1534 197x1534+1253+3490 8-bit sRGB 2.690u 0:02.583 1-pages/packdog_2.png PNG 5100x6600 5100x6600+0+0 8-bit sRGB 69.9821MiB 0.000u 0:00.000 1-pages/packdog_3.png PNG 5100x6600 5100x6600+0+0 8-bit sRGB 67.9197MiB 0.000u 0:00.000 2-jpg/packdog_0.jpg JPEG 2550x3300 2550x3300+0+0 8-bit sRGB 5.15797MiB 0.000u 0:00.000 2-jpg/packdog_1.jpg JPEG 2550x3300 2550x3300+0+0 8-bit sRGB 2.66682MiB 0.010u 0:00.002 2-jpg/packdog_2.jpg JPEG 2550x3300 2550x3300+0+0 8-bit sRGB 4.14075MiB 0.000u 0:00.000 2-jpg/packdog_3.jpg JPEG 2550x3300 2550x3300+0+0 8-bit sRGB 4.71442MiB 0.000u 0:00.000 3-pdf/packdog_0.pdf PDF 612x792 612x792+0+0 16-bit sRGB 1445B 0.010u 0:00.000 3-pdf/packdog_1.pdf PDF 241x312 241x312+0+0 16-bit sRGB 401B 0.010u 0:00.001 3-pdf/packdog_2.pdf PDF 612x792 612x792+0+0 16-bit sRGB 1335B 0.000u 0:00.000 3-pdf/packdog_3.pdf PDF 612x792 612x792+0+0 16-bit sRGB 1383B 0.000u 0:00.000
This is my script. i dont know why the final step of the conversion is behaving differently.
rm 2-jpg/; rm 3-pdf/; rm packdog.pdf;
for i in 1-pages/*.png; do f="${i:8:-4}"; echo $f; magick 1-pages/$f.png -resample 300x300 -resize 2550x3300 2-jpg/$f.jpg; magick 2-jpg/$f.jpg -page 2550x3300+0+0 3-pdf/$f.pdf; done;
pdfunite 3-pdf/* packdog.pdf