Command parameters
Command line usage:

pdftojpg <-i PDF File> [-o Output] [Options]

-i <string> Specify PDF files or directory which contains PDF files.
-o <string> Specify output directory.
-d Include sub directory.
-# Keep original subfolder.
-f Set overwrite if output file is exist.
-a Do not popup message box after convert done.
-l <string> If no set. default save log in the same folder as program.
-l off Turn off to save log. default is turn on
-l "c:\pdf_image.log" Specify log file.
-u <string> User password.
-n <string> Owner password.
-z <int> Page zoom (50-200)%.
-v View the result image files after convert done.
-q <int> Set jpg/jpeg quality (1-100).
-x <int> Set horizontal resolution(DPI,change image quality) in generated image files,default 150.
-y <int> Set vertical resolution(DPI,change image quality) in generated image files,default 150.
-b <int> Set bit count in generated image files. 7(8bit grayscale), 8.
-g <int> Set rotate an image in 90, 180, 270,clockwise direction.
-w <int> Set width of the output image files.
-h <int> Set height of the output image files.
-e <string> Custom page range, Example:
"first" Extract the first page.
"last" Extract the last page.
"even" Extract even pages.
"odd" Extract odd pages.
"1,3,5-7,9-" Extract page 1, page 3, page 5 through 7, page 9 through end.
-r <string> Register.
-? Help.
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Example:
  pdftojpg -i "c:\input.pdf" -o "c:\output\" Extract "c:\input.pdf" to "c:\output\".
  pdftojpg -i "c:\input.pdf" -i "c:\input\" -o "c:\output\" -b 8 -q 70 Extract "c:\input.pdf" and all pdf files placed in"c:\input\" to "c:\output\", it is output 8bits jpg files and quality is 70.
  pdftojpg -i "c:\input.pdf" -o "c:\output\" -n password Extract Encrypted PDF file "c:\input.pdf" to "c:\output\", you will need a password.
  pdftojpg -i "c:\input.pdf" -o "c:\output\" -e 2-11 Extract pages 2 through 11 of "c:\input.pdf" to "c:\output\".
  pdftojpg -i "c:\input.pdf" -o "c:\output\" -w 320 -h 240 -v Extract "c:\input.pdf" to "c:\output\", it is output size 320x240 image files and view the result image files.