We are frequently being asked to give examples of what different pixel densities look like and we thought it would be useful to address this FAQ in a visual blog post. So here we go…
The images below speak for themselves and don't require much in the way of commentary. The images were taken with an Axis P1354-E outdoor network camera Axis P1354-E camera at a resolution of 1280x960 for consistency.
Please note there are no ‘official’ standards regarding pixel density and its relation to image purposefulness at the time of writing. The indicated purposefulness of each image is based on our own interpretation of what currently seems to be the accepted standards in the UK security industry.
Example image 1: 500 pixels/metre. Suitable for identification, recognition, observation and detection
Example image 2: 400 pixels / metre. Suitable for recognition, observation and detection
Example image 3: 300 pixels / metre. Suitable for recognition, observation and detection
Example image 4: 200 pixels / metre. Suitable for recognition, observation and detection
Example image 5: 150 pixels / metre. Suitable for recognition, observation and detection
Example image 6: 100 pixels / metre. Suitable for observation and detection
Example image 7: 50 pixels / metre. Suitable for detection (note: down to 20 pixels/metre is also deemed suitable for the purpose of detection)
What do we mean by the terminology used? In simple terms:
- Identification: identification of an unknown individual or object
- Recognition: recognition of a known individual or object
- Observation: being able to interpret what is going on
- Detection: detection of activity within a scene
Obviously, in these examples, we have ignored the effects of lighting levels and visibility, which will always need to be taken into consideration when choosing your cameras.
We hope you will find this useful as a simple guide and encourage you to share your experiences and comments with us.
We would like to thank Axis Communications for their help with creating this information.
Other useful tools and information: