The answer is YES. Pix4Dmapper Photogrammetic Software can process both images with and without geolocation.
However, it is advisable to know the position of the camera for at least 50% of the images you have, if you want to achieve the best quality and faster results. As far as the IMU parameters (aircraft’s speed, orientation, and gravitational forces) are concerned, Pix4Dmapper doesn’t require them, as orientation parameters are computed during the processing. IMU values are only used as information in the quality report to indicate the accuracy of the input values and the optimized obtained values.
Warning: If less than 3 images are geolocated, lower precision results are expected.
Using Pix4Dmapper with Images without geolocation
You can process images with no photo geolocation but when doing so, that is when no Ground Control Points are used, the final results have no scale, no orientation and no absolute position information. They consequently can not be used for measurements, overlay and comparison with previous results. Besides, it can also occur that they generate an inverted (upside downn) 3D model in the rayCloud.
Using Pix4Dmapper with images with known position with a camera with built-in GPS tagging
Most of the major manufacturers use GPS tagging; Panasonic, Sony, and Canon are some well known camera manufacturers that have released these cameras so far. Most of these cameras save the GPS coordinates in the images’ EXIF data. Pix4Dmapper reads this information from the EXIF data in order to automatically import the image geolocation into the software.
Warning: if the frequency with which the tag is updated GPS (refresh) is slow and more photos are taken within that interval, the pics will have the same GPS position and the Pix4Dmapper processing will be unable to calibrate the images or worse, it will be unsuccessful. We, therefore, recommend using cameras with a very fast refresh GPS for optimal results. Example: if my camera has a TAG GPS frequency that is updated every 10 seconds and I take 3 photos from different locations in these 10 seconds, my 3 photos will have the same GPS location even if I moved to take my pictures … If I use a camera with a GPS refresh 2-3 seconds GPS refresh, I will not have this problem.
Images with known position using an external GPS logger
GPS loggers are very light devices (easily placed on a UAV) that can collect position information for the images. They register latitude, longitude and altitude values for each camera position while shooting. These values are saved to a file that can be imported directly into Pix4Dmapper if it has the correct file format.
