What steps will reproduce the problem?
1. convert a pdf with the command: pdf2image c:\test.pdf
2. png files are generated, and an empty file is generated too, named "c:\test"
What is the expected output? What do you see instead?
the empty json file should not generated if the json parameter is not specified
in command line
What version of the product are you using? On what operating system?
0.52
Please provide any additional information below.