Putting Webcam Resolutions In Focus

Webcams have provided people a means of keeping in touch. Using video in blogging, emails, video chat, and video conferencing web cams have made communication easier than ever before. Resolution is one of the most common considerations, when making a webcam purchase. What most consumers do not know is there are two types of resolutions. There are software enhanced (interpolated) and true sensor resolutions. Understanding the difference helps consumers make the best decision for their budget and needs.

True Sensor Resolution
The sensor of the webcam is made up of a number of points that are sensitive to light. There can be millions of these points on a high quality sensor. These sensors are typically rated in Mega Pixels, or millions of pixels. The higher the rating, the more detail an image can have. A highly detailed image can be viewed in larger formats without pixelation or distortion. Some refer to this as the true resolution. The higher the resolution is, the more expensive and fragile the sensor becomes.

Interpolated Resolution
Interpolation is one of several mathematical formulas used to increase the number of pixels in an image. Interpolation is done through the use of software. The software analyzes the image and adds pixels, creating them from surrounding pixels.



The original image








Software adds pixels









Software compares surrounding pixels to determine what the new pixels should look like.








Non interpolated image magnified.









From these base examples, it can be seen that the use of software interpolation smoothes out the image. Because interpolation does not use true image pixels, there is some quality loss, but far less than a larger image that is non-interpolated.

Webcam Application
The use of software interpolation allows webcam designers to use cheaper lenses to achieve higher quality images. Most webcams are able to produce a standard 640x480 video stream, which is equal to 300k Pixel (300 thousand pixels). Still frame images are often of higher resolutions, because they use software interpolation. By using software interpolation, webcams are able to produce high resolution images without the high cost of advanced lens sensors.

Images used came from a great website on imagery, learn more from the site, Cambridge in Colour.