In the recent years, many industrial augmented reality (IAR) applications are shifting from video to still images to create a mixed view. This new type of application is called photo-based augmented reality. In order to guarantee the success of these applications, a simple and efficient registration method is required. We present a new method to register an image to a CAD model using a single keyframe. This registration is based on sparse 3D information from the model linked to the keyframe during its offline registration. We demonstrate this method in our in-house IAR software for visual inspection and documentation: VID.

Photo-based augmentation is a growing field in particular for industrial augmented reality (IAR) applications. Registration is at the core of every photo-based AR software. This alignment of the image to the 3D model coordinate system is usually achieved with fiducial markers. When a single keyframe is used, the unknown baseline length has to be estimated in order to superimpose virtual models onto the image. In this paper, we develop an automatic algorithm to augment the relative pose, estimated using a single keyframe, into a full pose that will permit superimposition. This is performed by propagating known 2D-3D correspondences to the target image using perspectively corrected template matching and followed by a refinement of the estimated full pose that combines geometric and photometric information. The performance and the stability of the proposed method is extensively demonstrated on synthetic data and its applicability is shown within an industrial AR software for visual inspection and documentation.