Convert png, jpg files to pdf, combine them into a merged pdf

generate-merged-pdf-from-png-and-jpg.sh

# Code for downloading Google books is present in tts-converter/DownloadGoogleBooks.kt

for i in $(find . -maxdepth 1 -name "*.png" -print | sort -V -k1); do pdfjam --outfile ${i//png/pdf} $i; done
for i in $(find . -maxdepth 1 -name "*.jpg" -print | sort -V -k1); do pdfjam --outfile ${i//jpg/pdf} $i; done

gs -dNOPAUSE -sDEVICE=pdfwrite -sOUTPUTFILE=merged.pdf -dBATCH `find . -maxdepth 1 -name "*.pdf" -print | sort -V -k1`