Elphel develops high-performance digital cameras, image processing, 3D imaging and machine learning. The firm offers free software and open hardware. Elphel imaging systems are primarily used for scientific applications that require designs to be user-modifiable at all levels - from the hardware and FPGA code to the system and application software. Elphel cameras offer a combination of high performance and complete openness at all levels from mechanical and circuit design, FPGA RTL code up to all levels of the system and application software. All the design files are publicly available at Elphel web sites and through the popular GitHub repository. These features make Elphel products attractive for scientific research and innovative products. Elphel technology has been referenced in over a hundred scientific publications, and at least six US patent applications that use or reference Elphel products.
Since 2012 Elphel has been developing methods of precise camera calibration and designing photogrammetric multiple-view cameras with thermally compensated SFE resulting in 0.05 pix reprojection error for 5 MPix sensors. We developed modified checkerboard pattern where each edge consists of 2 arcs - this modification from traditional straight lines checkerboard makes power spectrum uniform and improves accuracy of the indirect measurement of the PSF for subsequent optical aberration correction of the acquired images.
From 2016 till present we are working on very long range 3D reconstruction and achieved 0.05 pix disparity resolution by combining several technology components developed by Elphel.
Use of multiple image sensors (4+) instead of conventional binocular stereo.
Advanced calibration, frequency-domain rectification, aberration correction, filtering, and 2D phase correlation.
Training and inference of the Deep Neural Network to predict the depth map from 2D correlation results. DNN analyzes context, extracts object edges, separates background, fuses depth map with textures.
Elphel MNC393-XCAM camera is a narrow baseline 3D perception system providing 10% ranging accuracy at 2000 m, by utilizing the achieved 0.05 pix disparity resolution.