https://askubuntu.com/questions/150100/extracting-embedded-images-from-a-pdf/1187844#1187844

Check you have it (often pre-installed) with

pdftoppm -v

Example you can try without overwriting anything. Open a Terminal in the folder and do (you can, if you want, change your pdf name to imgtesttt.pdf and just copy-paste these 2 commands).

mkdir -p images && pdftoppm -jpeg -jpegopt quality=100 -r 300 imgtesttt.pdf images/pg

(This is the highest quality jpeg available, although you can set from 0 to 100. Jpegs will be around .2 to 2mb with 8.5x11" pages.

or for png

mkdir -p images && pdftoppm -png -r 300 imgtesttt.pdf images/newimagename

(Note that this does two things. First it creates a folder called 'images', so to create a folder called 'book' you need to change that as well as the latter part of the command)

To do several pdfs that are in the same folder

mkdir -p XXXXX && pdftoppm -png -r 300 XXXXX.pdf XXXXX/XXXXX

mkdir -p YYYYY && pdftoppm -png -r 300 YYYYY.pdf YYYYY/YYYYY

A more simple command

mkdir -p images && pdftoppm imgtesttt.pdf images/pg

(where it creates a folder in that folder called ‘images’ and makes a .ppm image file of every page. Where 300 is 300dpi (default is 150dpi if you don't specify)

Note: you can make:

• PPM (default)
• PNG (with -png)
• JPEG (with -jpeg)
• TIFF (with -tiff)

A tiff example:

mkdir -p images && pdftoppm -tiff -r 300 mypdf.pdf images/pg (300dpi, where each image takes 15-45 seconds. Single core process, so not any faster on faster machines)

A simpler jpeg example:

mkdir -p images && pdftoppm -jpeg -r 300 mypdf.pdf images/pg

I just did png this way:

mkdir -p images && pdftoppm -png -r 300 mypdf.pdf images/pg

image shows jpeg 300dpi and png 300dpi at 100% and 200%

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