Components

The buffers in a container are called its components. In most respects, components are no different from other buffers allocated using the MbufAlloc...functions. Components have their own Aurora Imaging Library buffer identifier and can be used with Aurora Imaging Library functions that take a buffer. However, components are allocated and freed differently from other buffers. Typically, when a container is used as a destination for a grabbing or 3D processing function, that function will allocate and free the components automatically as required. You can allocate components manually using MbufAllocComponent, MbufCopyComponent, or MbufCreateComponent. If you need to free components manually, useMbufFreeComponent or free the container using MbufFree.

Only containers with the appropriate components can be processed using Aurora Imaging Library's 3D functions. See Preparing a container for display or processing for more information on 3D-processable point cloud (M_3D_PROCESSABLE) and 3D-processable depth map (M_3D_PROCESSABLE_DEPTH_MAP) containers.

Component type

Each component has a component type, which indicates the type of information stored in the component. For example, a component with the component type M_COMPONENT_RANGE stores 3D coordinates when the container stores a point cloud. Aurora Imaging Library uses the component type to determine what type of information a component stores about the points in a point cloud container.

Typically, a component's component type is set automatically during acquisition. You can set a component's component type manually usingMbufControlContainerwithM_COMPONENT_TYPE.

Group, region, and source ID

If you grab data from a 3D sensor that transmits data in a format suitable for grabbing into a container, it might assign each component a group, region, and/or source ID number. Typically, components which have the same group, region, or source ID are associated in some way; for example, if your 3D sensor transmits the range and confidence components for multiple 3D scenes in a single grab, each set of components might have a different group ID. These component ID numbers can be inquired using MbufInquireContainerwith M_COMPONENT_GROUP_ID,M_COMPONENT_REGION_ID and M_COMPONENT_SOURCE_ID respectively.

You can create a child container that contains only the components of a single group, using MbufChildContainerwith M_COMPONENT_BY_GROUP_ID(). You can then call MbufConvert3dwith the child container to convert the 3D data to a 3D-processable point cloud container.

Note: Your 3D sensor might transmit group, region, and source IDs that are not sequential. Refer to your 3D sensor manual to determine what ID numbers it will assign to components.

Component criterion

Some functions, such as MbufFreeComponent, allow you to perform operations on the components of a specified container (such as freeing those components) by specifying a criterion. In some cases, these criteria (such as M_COMPONENT_BY_INDEX()) can only refer to a single component in the container. In other cases they can potentially refer to several components in the container (such asM_COMPONENT_INTENSITY, which specifies all intensity components in the container).

By default, 3D functions only apply the operation to core components of a 3D-processable point cloud or depth map container. These components include the range, confidence, reflectance, normals, intensity, mesh, matrix (depth map), and region (depth map); for more information, see MbufInquireContainer with M_3D_PROCESSABLE and M_3D_PROCESSABLE_DEPTH_MAP. Some functions (such as M3dimMerge) allow you to apply the operation to all components, including custom components (M_COMPONENT_CUSTOM + n), if you specify M_APPLY_TO_ALL_COMPONENTS. The components must have the same dimensions as M_COMPONENT_RANGE; otherwise, they will be copied to the destination container unmodified. Note that if a custom component has an associated calibration context, the component's information is modified/copied, but its calibration context is discarded.

Note: Some functions, such as MbufInquireContainer, require that you specify a criterion that identifies only a single component in the container. For these functions, an error will be generated if there is more than one component in the container that meets the specified criterion.