How to convert pictures

To merge many (scanned) jpeg files into one pdf file just do:

convert *.jpeg  all_pictures.pdf

The result will be one single pdf file with one picture / page. To extract the pictures from the pdf file as png for use with memory sticks:

convert all_pictures.pdf pages-%03d.png

The result will be n-pages png-files pages-001.png etc.
The resulting resolution can be adjusted by:

convert -resize 1000x1200 all_pictures.pdf pages-%03d.png

For more information on the powerful tool convert which is a command interface
to ImageMagick contact this webpage