Convert PDF to PNG in Ubuntu

Install this

sudo apt install poppler-utils

Basic command

pdftoppm -png <input_file> prefix_output_filename

Advanced commands

for f in *.pdf
do
new_f=${f::(-4)}
echo ${new_f}
pdftoppm -png $f ${new_f}
done

What the above command doing is:

for each pdf file, split the file by page and save them as png file with

pdf_filename-1.png

pdf_filename-2.png

…

Explanation of more commands

https://linux.die.net/man/1/pdftoppm#:~:text=Pdftoppm%20converts%20Portable%20Document%20Format,%2C%20PPM%2Droot%2Dnnnnnn.