We introduce here an improved design of the Uniform Marker Fields and an algorithm for their fast and reliable detection. Our concept of the marker field is designed so that it can be detected and recognized for camera pose estimation: in various lighting conditions, under a severe perspective, while heavily occluded, and under a strong motion blur. Our marker field detection harnesses the fact that the edges within the marker field meet at two vanishing points and that the projected planar grid of squares can be defined by a detectable mathematical formalism. The modules of the grid are grey scale and the locations within the marker field are defined by the edges between the modules. The assumption that the marker field is planar allows for a very cheap and reliable camera pose estimation in the captured scene. The detection rates and accuracy are slightly better compared to state-of-the-art marker-based solutions. At the same time, and more importantly, our detector of the marker field is several times faster and the reliable real-time detection can be thus achieved on mobile and low-power devices. We show three targeted applications where the planarity is assured and where the presented marker field design and detection algorithm provide a reliable and extremely fast solution.

In this article, we propose an instant matchmoving solution for green screen. It uses a recent technique of planar uniform marker fields. Marker fields are an extension of planar markers used in augmented reality, offering better reliability and performance suitable for our task: tolerance to occlusion, speed of detection, and use of arbitrary low-contrast colors. We show that marker fields of shades of green (or blue or other color) can be used to obtain an instant and effortless camera pose estimation. We provide exemplar applications of the presented technique: virtual camera/simulcam and live storyboarding or shot prototyping. The matchmoving technique based on marker fields of shades of green is very computationally efficient - our measurements show that the matchmoving preview and living storyboard editing and recording can be easily done on today's ultramobile devices. Our technique is thus available to anyone at low cost and with easy setup, opening space for new levels of filmmakers' creative expression.

One limitation of existing fiduciary markers is that the camera motion is tightly limited: the marker (one of the markers) must be visible and it must be observed at a proper scale. This paper introduces a fractal structure of markers similar to matrix codes (such as QR-code or Data Matrix): the Fractal Marker Field. The FMF allows for embedding markers of a virtually unlimited number of scales. At the same time, for each of the scales it guarantees a constant density of markers at that scale over the whole marker field's surface. The Fractal Marker Field can provide unprecedented freedom of motion to camera-based augmented reality applications.

In various applications, a wider area needs to be covered by fiduciary markers but a large marker cannot be used because only a fraction of the area is to be viewed by the camera. Such an area can be covered by a number of small markers with unique identifiers. However, with the camera freely moving in the scene and with occluders present, it is difficult to ensure that at least one of the individual markers is completely visible, unless the markers are small and numerous. In that case, the markers are not recognizable from larger distances.