[SOLVED] using imagemagick convert in bash

Hi to all, I wish you all a happy and prosperous 2020!

From this old thread I am trying to convert .pdf to a series of .jpg

I get this:

Quote:

pedro@pedro-newssd:~/babystuff/mergedPdf$ convert -colorspace RGB -interlace none -density 300x300 -quality 100 exam1.pdf exam1.jpg convert-im6.q16: not authorized `exam1.pdf' @ error/constitute.c/ReadImage/412. convert-im6.q16: no images defined `exam1.jpg' @ error/convert.c/ConvertImageCommand/3258. pedro@pedro-newssd:~/babystuff/mergedPdf$

I was sort of hoping convert would number the .jpgs automatically. Looks like that is not so.

This is from Imagemagick.org

Quote:

Filename References Optionally, use an embedded formatting character to write a sequential image list. Suppose our output filename is image-%d.jpg and our image list includes 3 images. You can expect these images files to be written: image-0.jpg image-1.jpg image-2.jpg

So I tried this, get the same error:

Quote:

pedro@pedro-newssd:~/babystuff/mergedPdf$ convert exam1.pdf exam1_%d.jpg convert-im6.q16: not authorized `exam1.pdf' @ error/constitute.c/ReadImage/412. convert-im6.q16: no images defined `exam1_%d.jpg' @ error/convert.c/ConvertImageCommand/3258. pedro@pedro-newssd:~/babystuff/mergedPdf$

How do I tweak this please?

My goal is to use pytesseract to convert a lot of old Chinese exams to Chinese text. Reading about this, I got the idea that maybe .tiff was better than .jpg.

Is that true?