Vectorized fonts in PDF output of ImageMagick montage?

I am using ImageMagick (under Linux) to make a 3x3 montage of nine PNGs which I have, and label them. Desired is PDF output with vectorized fonts as the labels. I use this command:

montage -label '%t' *.png -geometry +3+3 out.pdf

The result looks exactly like I want it to be, but the labels of the panels are actually bitmaps! I.e. if I zoom into the PDF I can see that the label text consists of pixels, and I can not further search for the labels etc in the resulting PDF.

Is there any way how I can make it so that the labels are vectorized, proper fonts in the PDF? If yes, how do I specify this?

Solution 1:

I don't think this is possible with ImageMagick as it does not produce true vector graphics. From the ImageMagick site (http://www.imagemagick.org/Usage/formats/#vector):

In other words, any output from IM will never be a true vector format. While it can convert its internal raster format into a vector format file, the result is only a superficial vector image wrapper around an image in raster format. And unless the raster image is defined properly (at the right resolution) for the output device, the result will not be particularly good. Unfortunately new users to IM do not know anything about this. They see IM as a converter that can convert say PDF to Postscript, producing images with 'blocky' aliasing effects, 'washed out' colors, or blurry images that just do not look good at all, on the intended output device.

If you want to investigate 'vectorizing' the whole output one of the examples on the ImageMagick site suggests using Abobe software or AutoTrace (which is open-source).