Multisignal ground truth data, specified as agroundTruthMultisignalobject or vector ofgroundTruthMultisignal对象。

EachgroundTruthMultisignalobject ingTruthmust include all the signals specified in thesignalNamesinput.

In addition, each object must include at least one marked label per gathered label definition. SupposegTruthis agroundTruthMultisignal对象包含标签数据or a single video signal namedvideo_front_camera。The object contains marked rectangle region of interest (ROI) labels for thecarlabel definition but not for thetrucklabel definition. If you use this syntax to gather labels of typeRectanglefrom this object, then thegatherLabelDatafunction returns an error.

labelData = gatherLabelData(gTruth,"video_front_camera",labelType.Rectangle);

Names of the signals from which to gather label data, specified as a character vector, string scalar, cell array of character vectors, or string vector. The signal names must be valid signal names stored in the input multisignal ground truth data,gTruth。

To obtain the signal names from agroundTruthMultisignalobject, use this syntax, wheregTruthis the variable name of the object:

gTruth.DataSource.SignalName

Example:'video_01_city_c2s_fcw_10s'

Example:"video_01_city_c2s_fcw_10s"

Example:{'video_01_city_c2s_fcw_10s','lidarSequence'}

Example:["video_01_city_c2s_fcw_10s" "lidarSequence"]

Label types from which to gather label data, specified as alabelTypeenumeration scalar,labelTypeenumeration vector, or a cell array oflabelTypeenumeration scalars and vectors. ThegatherLabelDatafunction gathers label data for each signal specified by inputsignalNamesand eachgroundTruthMultisignalobject specified by inputgTruth。The number of elements inlabelTypesmust match the number of signals insignalNames。

Gather Label Data for Single Label Type per Signal

To gather label data for a single label type per signal, specifylabelTypesas alabelTypeenumeration scalar or vector. Across allgroundTruthMultisignal对象ingTruth,gatherLabelDatafunction gatherslabelTypes(n)label data fromsignalName(n), wherenis the index of the label type and the corresponding signal name whose label data is to be gathered. Each returned table in the outputlabelDatacell array contains data for only one label type per signal.

In this code sample, thegatherLabelDatafunction gathers labels of typeRectanglefrom a video signal namedvideo_front_camera。The function also gathers labels of typeCuboidfrom a lidar point cloud sequence signal stored in a folder namedlidarData。ThegTruthinput contains thegroundTruthMultisignal对象from which this data is to be gathered.

labelData = gatherLabelData(gTruth,。..["video_front_camera","lidarData"],。..[labelType.Rectangle,labelType.Cuboid];

To gather label data for a single label type from separate signals, you must repeat the label type for each signal. In this code sample, thegatherLabelDatafunction gathers labels of typeRectanglefrom thevideo_left_cameraandvideo_right_cameravideo signals.

labelData = gatherLabelData(gTruth,。..["video_left_camera","video_right_camera"],。..[labelType.Rectangle,labelType.Rectangle];

Gather Label Data for Multiple Label Types per Signal

To gather label data for multiple label types per signal, specifylabelTypesas a cell array oflabelTypeenumeration scalars and vectors. Across allgroundTruthMultisignal对象ingTruth,gatherLabelDatafunction gatherslabelTypes{n}label data fromsignalName(n), wherenis the index of the label types and the corresponding signal name whose label data is to be gathered. The function groups the data for these label types into one table per signal pergroundTruthMultisignalobject.

In this code sample, thegatherLabelDatafunction gathers labels of typeRectangleandLinefrom thevideo_front_cameravideo signal. The function also gathers labels of typeCuboidfrom a lidar point cloud sequence signal stored in a folder namedlidarData。ThegTruthinput contains thegroundTruthMultisignal对象from which this data is to be gathered.

labelData = gatherLabelData(gTruth,。..["video_front_camera",。.."lidarData"],。..{[labelType.Rectangle labelType.Line],。..labelType.Cuboid};

Valid Enumeration Types

You can specify one or more of these enumeration types.

To gather label data for scenes, you must specifylabelTypesas thelabelType.Sceneenumeration scalar. You cannot specify any other label types withlabelType.Scene。

Sample factor used to subsample label data, specified as a positive integer. A sample factor ofKincludes everyKth signal frame. Increase the sample factor to drop redundant frames from signals with high sample rates, such as videos.

Example:'SampleFactor',5