Bug with ocr_cpu_arg

[R-e-d-J]

Following the k2pdfopt doc, there muse be a space between ocr_cpu_arg_name and the %, like this -ocr -nt -50.

So I think there is a minor bug in your code

        # negtive integer means percentage
        ocr_cpu_arg = (
            ocr_cpu_arg_name + '-' +
            strvarOcrCpuPercentage.get().strip()
        )

the third line should be : ocr_cpu_arg_name + ' -' + (with a space before the minus sign).