Elphel Eyesis4Pi
Contents
About
Elphel Eyesis4Pi is an open hardware / free software panoramic camera solution that is able to capture high-resolution - 64 MPix total (120 MPix before stitching) - 360° panoramas at a rate up to 5 frames per second at full resolution. It is the successor of the Elphel Eyesis. Images are recorded to 8 solid-state-discs (Eyesis4Pi Data Storage) which can store up to 11 hours of footage at full resolution. Meta-data like GPS-coordinates (geotags), viewing direction, movement speed, etc. are directly embedded into the images EXIF fields. Eyesis4Pi uses 24 sensor-front-ends and high-grade lenses that are triggered simultaneously with microsecond accuracy to ensure a full homogeneous spherical snapshot.
Usage Scenarios
The system was designed to be small and lightweight with a minimal distance between the entrance pupils (46.5mm) to achieve lowest possible parallax.
The primary usage scenario is to mount Eyesis4Pi on the roof of a vehicle. When driving at 50 mph (22.3 m/s) and recording at 5 FPS a full panorama is captured every 4.46 meters.
Operation & Monitoring
Eyesis is controlled from a laptop, via a web-based interface (Eyesis GUI). Which also displays real-time previews of your captured panorama footage.
Eyesis is supplied with 110V/220V AC and can be used with car power adapter (inverter), when mounted on a car roof. Power consumption is around ???W.
Models
4π (or 4Pi) corresponds to a full full spherical (360°x180°) field of view in steradians.
There are 2 version of the camera Eyesis4Pi with 24 image sensors and full sperical field of view and Eyesis3Pi with 16 sensors (without 8 bottom modules) with slightly smaller field of view.
Comparison between Eyesis and Eyesis4Pi
| Parameter |
Eyesis |
Eyesis4Pi (Eyesis 3Pi without 8 bottom modules) |
Notes |
|---|---|---|---|
| Combined field of view (steradians) |
3*π |
4*π (3*π) | |
| Number of image sensors |
9 |
24 (16) |
|
| Angular resolution +/-30° from the horizon |
≥4.2Mpix/steradian |
≥4.2Mpix/steradian |
1 |
| Angular resolution +30° to +90°(zenith) |
≥0.83Mpix/steradian |
≥4.2Mpix/steradian | 1 |
| Angular resolution -30° to -90°(nadir) | none | ≥4.2Mpix/steradian (none) | 1 |
| Combined megapixels | 45.0 | 120.0 (80.0) | |
| Combined megapixels (w/o overlapping areas) | 34.0 | 64.0 (48.0) | |
| Combined megapixels (w/o overlapping areas, worst case resolution) |
29.0 | 52.8 (39.6) | 1,2 |
| Distance between entrance pupils of adjacent horizontal lenses |
34.5mm | 46.5mm | |
| Distance between entrance pupils of horizontal and top/bottom lenses |
75mm | 50mm | 3 |
| Maximal frame rate | 5fps | 5fps | 4 |
| Maximal recording data rate | 48MB/s | 128MB/s (96Mb/s) | |
| Maximal direct network data rate | 30MB/s | 80MB/s (60MB/s) | |
| GPS receiver | external, USB | External/internal, USB/RS232 | |
| GPS pulse-per-second input | no |
yes |
|
| IMU | none | ADIS163xx,ADIS164xx | |
| Data unload | removable SSD in cradles | eSATAx2 | |
| Storage devices type | 2.5″ SSD | 1.8″SSD | |
| Number of storage devices | 3 |
8 (6) |
|
Notes:
- Angular resolution per pixel differs in the sub-camera FOV, minimal resolution is used.
- Zenith area for Eyesis (covered by fisheye lens) is calculated separately.
- For Eyesis the distance is measured from the entrance pupil of the horizontal lens to that of the top fisheye, for Eysis-4pi – to the entrance pupil of the lens immediately above/below the first one.
- Frame rate may be limited by the recording (or network if the SSD are not used) datarate for high compression quality (>0.3 bytes/pixel), required for the aberration correction.
