Image Encoding (watermarking) – read me first
Encoding images with Linkz is easy. But certain ground rules are necessary. Just as images for Web, video and print all have different production characteristics, images for Linkz requires a few guidelines. Generally speaking – if you can print an image – you can upload and encode it with Linkz.
- You must provide the final print size of the image. Remember – cropping an image is fine (Linkz watermarks are repeated throughout the image) but enlarging or reducing an image plus or minus 10 to 15% will start to degrade the speed of the payoff when scanned by the smart phone.
- “Image width” is the actual dimension of the image if it was printed with no cropping, no reduction and no enlargement – not the necessarily the size of the image in a page layout application. Often, an image is enlarged or reduced more than 10% in a layout application – using the layout application dimensions will result in poor scanning. If you reduce or enlarge the image in your layout application, this scaling factor must be taken into account in the Linkz “Image Width” dimension. Generally, cropping an image in your layout application is fine – provided there is enough of the image to be scanned – typically at least 3x3cm.
- Images must be a JPEG or TIFF file. See the PDF handling FAQ page to see how to deal with vector or PDF files. Of course, for a fee, we will do the required adjustments.
- Encoding must have color data to work with – this means image areas with little to no dots when printed will not scan. At the other end, if an image’s density is too large – over 300% ink coverage for CMYK or 85% for single color – scanning can fail as the smartphone camera cannot distinguish tonal variations in the image.
In short – no pure whites and no super heavy densities. But despair not! See the How to work with Text FAQ for how to deal with areas of very low color data.