Automator - Render multiple PDF as JPG and keep PDF file name

Using homebrew, do the following in the Terminal.

brew update

brew upgrade

brew install ghostscript

brew cleanup

The ghostscript 9.26_1 executable will be installed in /usr/local/bin as gs.

Life is too short to be dealing with internal Automator action mischief. I am changing the solution to a three-action Automator solution. Once you have Ghostscript 9.26.1 installed, edit your Automator application. You do this by launching Automator, cancelling its file dialog, and choosing Open Recent… and your application name.

Keep only these three actions:

1. Ask for Finder Items
2. Filter Finder Items
3. Run Shell Script

Clear the contents from the Run Shell Script action, and copy/paste the following into it:

DPI=300
PAGEMAX=10
OUTFOLDER="$HOME/Desktop/PDF/"

for f in "$@"
do
	page_cnt=$(mdls -name kMDItemNumberOfPages "$f" | awk '{print $NF}')
	# force ten page limit if higher page count
	[[ page_cnt -ge PAGEMAX ]] && page_cnt=$PAGEMAX

	# simultaneously strip path and extension
	shopt -s extglob
	BASE="${f//+(*\/|.*)}"
	shopt -u extglob

	# The intents set to zero is perceptual rendering
	/usr/local/bin/gs -q -dSAFER -sDEVICE=jpeg -r$DPI -dTextAlphaBits=4 -dGraphicsAlphaBits=4 \
    	-dLastPage=$page_cnt -dTextIntent=0 -dRenderIntent=0 -dImageIntent=0 \
    	-dFIXEDMEDIA -dPDFFitPage -o $OUTFOLDER${BASE}_%02d.jpeg "$f"
done



The script will limit the page count to 10 if it is greater in the PDF, and its does sequential numbers of imaged pages correctly.

In the Bash script, when Ghostscript is interrupted, it leaves .jpeg files in a temporary location. These can impact the next run. You should remove these in the Terminal in this location:

cd $TMPDIR

or

cd $TMPDIR/TemporaryItems

After adding -dJPEGQ=100, I would restructure the Ghostscript content by forcing a line continuation character at the end of that line:

None of my original portrait oriented PDF documents that I tested produced rotated images, so curious about that issue. The png image format will give you better text clarity and document compression, because JPEG is really intended for photographs, and not especially text.

The following Automator application workflow allows you to select multiple PDF files, and render the PDF pages as 300 dpi JPEG. Each JPEG page is renamed to append _nn after the name and before the extension. The original PDF filename is retained for each image.

A 10-page PDF named render_images.pdf will result in image files: render_images_01.jpeg ... render_images_10.jpeg.

You set the output folder in the Run Shell Script action. It defaults to a JPEG folder on the Desktop. You save this Automator Application to your Desktop, and double-click to Run. You select multiple PDF by depressing the ⌘ key.

Here is the content for the Run Shell Script:

OUTDIR="$HOME/Desktop/JPEG/"

for f in "$@"
do
	# a by product of the render is generation (nn) sets (e.g. foo nn_01.jpeg) and Ruby removes to make (foo_01.jpeg)
	OUTFILE="$(ruby -e 'puts File.basename(ARGV.first).split(/(?<=\s)\d+(?=_)/).map(&:strip).join;' "$f")"
	mv "$f" "$OUTDIR$OUTFILE"
done



What operating system version are you getting these results? I tested on High Sierra 10.13.6 (17G6030) and Mojave 10.14.4 (18E226). Same version of Ruby on both.

In Terminal, enter the following commands. TMPDIR is the location that Automator writes your JPEG files with the format document nn_nn.JPEG. Remove any *.JPEG that you find in that location:

cd $TMPDIR

ls *.JPEG

rm -f *.JPEG

and to return to your home directory:

cd -

Clean out the files from the output folder, and run the Automator application again.

The sole purpose of the OUTFILE Ruby code is to remove the single whitespace and number that precedes the _nn.JPEG, and I just tested it again using one of your examples from your preceding post and it worked perfectly.

I also have a Ghostscript solution in a Bash script that does the same thing in a single Run Shell Script action.

You were supposed to replace the contents of the Run Shell Script action with what I posted this morning. All I did was introduce a line continuation backslash on the first line of the existing Ghostscript command syntax. Unless the Note tool is somehow garbling what you receive. I couldn't paste into the < > tool which would have preserved accurate syntax.

Spelling counts. That is cd $TMPDIR, not cd $TMDIR. 😉

The Terminal command:

cd $TMPDIR

ls *.jpeg *.jpg

or

cd $TMPDIR/TemporaryiTems

ls *.jpeg *.jpg

There is no open cd $TMPDIR command.