Determining resolution of specific image in PDF document?

Can GDAL be used to determine the resolution of an image embedded inside a PDF? If not GDAL, is there another method?

I’m using gdal_translate to convert TIF+TFW files into geospatial PDF. I know the resolution of the TIF, but I’m not sure that gdal_translate retains that resolution when it puts the image into the PDF file. I need a way to examine the image in the resulting PDF to determine what gdal_translate is doing.

The motivation is that these geospatial PDF files are being developed for use in Avenza PDF Maps, and that app makes use of the embedded image resolution when initially importing and tiling the PDF.