Image Net

Image Net is a site which has organized more than 14 million images into more than 21,000 different categories and subcategories. So if one searches for the term, 'computer' one gets a list of 26 categories (or 'synsets') that this term may apply to.

If we select just one of these synsets we are taken to a link to hundreds of images which fall in a category and a collapsible tree which shows the particular category's place in the overall hierarchy.

Image Net appears to get better organized results than Google Image search, and it can help you delineate the particular object or concept you want to show a photo of in your presentation or demonstrative.

Mixed Raster Content

You can reduce the size of a PDF by choosing the mixed raster content method. MRC compresses or removes the color background of a document so that only text and pictures are shown against a white background. The picture objects themselves (photos, diagrams, etc.) may also be slightly compressed.

As you can see in this screen grab when saving a PDF in Nuance Power PDF Advanced, you have the option to select, 'MRC PDF Document'.

If you click on settings, you can adjust the conversion rate. Minimal will generate the smallest possible file. Good will reduce image quality somewhat. Lossless preserves the original image quality. Using this method with 'Good' option I was able to reduce on 52 MB file to 4.5 MB this evening.

Here we can see the slight reduction in image quality between the compressed image on the top, and the original image on the bottom. Not much of a compromise.

Choosing the Minimal option would only reduce the file size a few KB more.

How to convert bitmaps to vector images

Raster based images such as bitmap files will pixelate when you zoom in on them. So for example an apparently clear, crisp image like this one:

. . . will have a grid like pattern when you zoom in:

If you want to convert these images you can use the online service, www.vectormagic.com . As you can see the choppy image is converted to smooth lines: