It’s easy to tell whether your PDF file is a raster or vector format by viewing it in Adobe Acrobat. This is important since the two file types are converted differently. Vector PDF files are best transformed through data extraction. This is accurate and precise and involves minimal manual clean-up. Raster PDF files are traced since there is no data to extract. This is an approximation and requires operator involvement as well as manual clean-up. Visual Integrity is specialized in tools for vector conversion and will produce high-quality, accurate drawings from vector PDF input. If a raster PDF or scanned drawing is run through our software, we will turn the flat image into a tracing layer for manual work-up.
Test #1 – The Blue Test
Start by opening your PDF file with Acrobat or Acrobat Reader. Click anywhere on the drawing. If it turns blue, it’s a scanned drawing. Depending on the quality of the scan, you may have some success with a raster-to-vector tool. Alternatives are to manually redraw it or outsource it to be redrawn by a service bureau.
Test #2 – The Zoom Test
Open your PDF file with Acrobat or Acrobat Reader. Use the Magnifying Control to zoom in on a detailed section of the file. At 100-150%, it may be hard to tell the difference. Continue zooming until you are at a magnification greater than 400%.
The section of the picture should be magnified on your screen and it should become apparent whether you have a vector or raster PDF file. The Vector PDF file will look clear and smooth at any resolution while the raster PDF will become dirtier and grainier the more it’s zoomed. In the example below, the section is enlarged 400%. Sometimes, it’s necessary to magnify the file more than 1000% when it’s a high-res scan to determine the file type.