Check if a file contains raster or vector elements? (pdf, eps, ai)

Question

Is there a way to check if a file has raster elements in it? I would be interested to do this for the .pdf, .eps and .ai formats.

If the file is only vector I am converting it to .svg and if it has some raster elements I have to convert it to .png file.

I am working in PHP but I can utilize any command line tools as well. For instance I am considering using Inkscape to do the actual conversion.

Answer 1

You could run this command on pdf files and check if anything raster exists on the file:

  grep -c -i "/image" thisfile.pdf

Answer 2

You could convert the image to EPS format, and search if "/ImageType" exists. The "/ImageType" means the following object is a raster image. If it doesn't exist in the whole EPS file, this EPS is a vector file.