This April we attached Eyesis camera to a backpack and took it to the Southern Utah. Unfortunately I did not finish the IMU hardware then so we could rely only on a GPS for tagging the imagery. GPS alone can work when the camera is on the car, but with a camera moving at pedestrian speed (images were taken 1-1.5 meters apart) it was insufficient even in the open areas with a clear view of the sky. Additionally, camera orientation was changing much more than when it is attached to a car that moves (normally) in the direction the wheels can roll. Before moving forward with the IMU data processing we decided to try to orient/place some of the imagery we took manually – just by looking through the panoramas, adjusting the camera heading/tilt/roll to make them look level and oriented so the next camera location matches the map. Just tweaking the KML file with the text editor seemed impractical to adjust hundreds of panoramic images so we decided to add more functionality to our simple WebGL panorama viewer, make it suitable for both walking through the panorama sets and for the editing orientations and locations of the camera spots. (more…)
June 15, 2011
May 19, 2011
For almost 3 years we had a possibility to geo-tag the images and video using external GPS and optional accelerometer/compass module that can be mounted inside the camera. Information from the both sensors is included in the Exif headers of the images and video frames. The raw magnetometer and accelerometer data stored at the image frame rate has limited value, it needs to be sampled and processed at high rate to be useful for the orientation tracking , and for tracking position it has to be combined with the GPS measurements.
We had developed the software to receive positional data from either Garmin GPS18x (that can be attached directly to the USB port of the camera) or a standard NMEA 0183 compatible device using USB-to-serial adapter. In the last case it may need a separate power supply or a special (or modified) USB adapter that can provide power to the GPS unit from the USB bus. (more…)
April 26, 2011
Tacking high-resolution panoramic images in the remote places, that can only be accessed by feet is an option now available with the Elphel-Eyesis 360 degree panorama camera. The camera’s size (1.3 x 0.3 meters) and relatively light weight (10kgs) allow to mount it on a backpack frame and carry by a person.
There were multiple requests for the backpack option by our customers since the development of Elphel-Eyesis camera, but other projects were of higher priority, until this spring, when we finally decided it was time to take Eyesis hiking. After all, we have worked hard on this project for many months, so we ought to have some fun with it too, and take panorama images of the places we knew and enjoyed for it’s scenery.
On April 19th, 2011, we took the Elphel mobile office to camp for 5 days in Southern Utah near the Goblin Valley State Park to try out Eyesis in beautiful places not yet available in continuous panoramic imagery, mainly because of their inaccessibility for car, ATV, or even a tricycle.
Hiking with Eyesis in the backpack (30 lbs/14 kg total weight with the battery pack) allows us to capture a continuous stream of geotagged (GPS) 360° panoramic images. With the current battery pack (just a regular UPS with lead battery) we can take up to one hour and forty minutes of footage at a rate of 5 frames per second.
February 28, 2011
Current state of the Eyesis project,
what worked and what did not. Or worked not as good as we would like it to
Most of the last year we spent developing Eyesis panoramic cameras, designing and then assembling the hardware, working on the software for image acquisition and processing. It was and continues to be a very interesting project, we had to confront multiple technical challenges, come up with the solutions we never tried before at Elphel – many of these efforts are documented in this blog.
We had built and shipped to the customers several Eyesis cameras, leaving one for ourselves, so we can use it for development of the new code and testing performance of the camera as a whole and the individual components. Most things worked as we wanted them to, but after building and operating the first revision of Eyesis we understood that some parts should be made differently.
January 3, 2011
December 21, 2010
This is a quick update to the Zoom in. Now… enhance. – a practical implementation of the aberration measurement and correction in a digital camera post published last month. It had many illustrations of the image post-processing steps, but lacked the most important the real-life examples of the processed images. At that time we just did not have such images, we also had to find out a way to acquire calibration images at the distance that can be considered “infinity” for the lenses – the first images used a shorter distance of just 2.25m between the camera and the target, the target size was limited by the size of our office wall. Since that we improved software combining of the partial calibration images, software was converted to multi-threaded to increase performance (using all the 8 threads in the 4-core Intel i7 CPU resulted in approximately 5.5 times faster processing) and we were able to calibrate the two actual Elphel Eyesis cameras (only 8 lenses around, top fisheye is not done yet). It was possible to apply recent calibration data (here is a set of calibration files for one of the 8 channels) to the images we acquired before the software was finished. (more…)
November 30, 2010
In my search for an affordable and reasonable solution of creating high-res panoramic river views I came along the Elphel camera and it’s photo-finish mode. As part of my ongoing projects Danube Panorama Project, Nile Studies and the new umbrella project River Studies, I am capturing virtually endless panoramic river views from a moving vessels with a slit- or line-scan method. I was using webcams or DV-cameras before, and all possible ways to upgrade to higher resolutions either seemed clumsy (I don’t want to be loaded with much more than a tiny laptop or tablet and the camera itself), very processing intense and/or expensive and far out of reach of my (very limited) budget.
The “all-purpose camera” Elphel stepped in as a good, reasonable and flexible solution for that task. The first season using an Elphel353 is over, so time to share some of my experiences with Elphel and it’s not so well know photo-finish mode for line-scanning.
November 18, 2010
“Zoom in. Now… enhance.” – a practical implementation of the aberration measurement and correction in a digital camera
This post describes the implementation of the optical aberration measurement and correction developed for Elphel Eyesis cameras, the same methods and the code (available under GNU GPLv3) can be applied to many other camera systems. With 1/2.5″ 5 megapixel sensor we achieved average sharpness improvement over the image area around 40% compared to the raw images, effectively doubling the resolved pixel count. The applied correction varied significantly with the location on the image plane, orientation and color channel, making simple uniform isotropic sharpening (i.e. with “unsharp mask” or similar filtering) useless in our case. The aberrations correction is based on well-known measurement and inversion of the system point-spread function (PSF), additionally we describe used frequency domain de-mosaic filtering (“spectral scissors”) compatible with the inverted PSF convolution.
October 27, 2010
While still polishing it; but you can see the sneak preview:
August 31, 2010
Today I created a tiny bit of OpenLayers code for the Eyesis display page. It is basically a demo what you can do by playing points of interest on a map. Displaying the panorama and a smaller map.
Currently I did not add a panorama player yet. But since it is only a matter of changing div’s that could be done easily. Personally I would like to go for a HTML5 kind of player, since for most browsers that would be the least resource intensive way of displaying. The code is available at http://eyesis.openstreetphoto.org/ there are some images there but only lowres from the initial stichting tryouts.