Dimensions¶
PDAL dimensions describe the combination of data’s type, size, and meaning. The following table provides a list of known dimension names you can use in Filters, Writers, and Readers descriptions.
| Name | Type | Description |
|---|---|---|
| Alpha | uint16 | Alpha |
| Amplitude | float | This is the ratio of the received power to the power received at the detection limit expressed in dB |
| Azimuth | double | Scanner azimuth |
| BackgroundRadiation | float | A measure of background radiation. |
| Blue | uint16 | Blue image channel value |
| ClassFlags | uint8 | Class Flags |
| Classification | uint8 | ASPRS classification. 0 for no classification. See LAS specification for details. |
| Curvature | double | Curvature of surface at this point |
| Density | double | Estimate of point density |
| Deviation | float | A larger value for deviation indicates larger distortion. |
| EchoRange | double | Echo Range |
| EdgeOfFlightLine | uint8 | Indicates the end of scanline before a direction change with a value of 1 - 0 otherwise |
| ElevationCentroid | double | Elevation Centroid |
| ElevationHigh | double | Elevation High |
| ElevationLow | double | Elevation Low |
| Flag | uint8 | Flag |
| GpsTime | double | GPS time that the point was acquired |
| Green | uint16 | Green image channel value |
| HeightAboveGround | double | Height Above Ground |
| Infrared | uint16 | Infrared |
| Intensity | uint16 | Representation of the pulse return magnitude |
| InternalTime | double | Scanner’s internal time when the point was acquired, in seconds |
| IsPpsLocked | uint8 | The external PPS signal was found to be synchronized at the time of the current laser shot. |
| LatitudeCentroid | double | Latitude Centroid |
| LatitudeHigh | double | Latitude High |
| LatitudeLow | double | Latitude Low |
| LongitudeCentroid | double | Longitude Centroid |
| LongitudeHigh | double | Longitude High |
| LongitudeLow | double | Longitude Low |
| LvisLfid | uint64 | LVIS_LFID |
| Mark | uint8 | Mark |
| NormalX | double | X component of a vector normal to surface at this point |
| NormalY | double | Y component of a vector normal to surface at this point |
| NormalZ | double | Z component of a vector normal to surface at this point |
| NumberOfReturns | uint8 | Total number of returns for a given pulse. |
| OffsetTime | uint32 | Milliseconds from first acquired point |
| Omit | uint8_t | Used to shallowly mark a point as being omitted without removing it |
| OriginId | uint32 | A file source ID from which the point originated. This ID is global to a derivative dataset which may be aggregated from multiple files. |
| PassiveSignal | int32 | Relative passive signal |
| PassiveX | double | Passive X footprint |
| PassiveY | double | Passive Y footprint |
| PassiveZ | double | Passive Z footprint |
| Pdop | float | GPS PDOP (dilution of precision) |
| Pitch | float | Pitch in degrees |
| PointId | uint32 | An explicit representation of point ordering within a file, which allows this usually-implicit information to be preserved when reordering points. |
| PointSourceId | uint16 | File source ID from which the point originated. Zero indicates that the point originated in the current file |
| PulseWidth | float | Laser received pulse width (digitizer samples) |
| Red | uint16 | Red image channel value |
| Reflectance | float | Ratio of the received power to the power that would be received from a white diffuse target at the same distance expressed in dB. The reflectance represents a range independent property of the target. The surface normal of this target is assumed to be in parallel to the laser beam direction. |
| ReflectedPulse | int32 | Relative reflected pulse signal strength |
| ReturnNumber | uint8 | Pulse return number for a given output pulse. A given output laser pulse can have many returns, and they must be marked in order, starting with 1 |
| Roll | float | Roll in degrees |
| ScanAngleRank | float | Angle degree at which the laser point was output from the system, including the roll of the aircraft. The scan angle is based on being nadir, and -90 the left side of the aircraft in the direction of flight |
| ScanChannel | uint8 | Scan Channel |
| ScanDirectionFlag | uint8 | Direction at which the scanner mirror was traveling at the time of the output pulse. A value of 1 is a positive scan direction, and a bit value of 0 is a negative scan direction, where positive scan direction is a scan moving from the left side of the in-track direction to the right side and negative the opposite |
| ShotNumber | uint64 | Shot Number |
| StartPulse | int32 | Relative pulse signal strength |
| UserData | uint8 | Unspecified user data |
| WanderAngle | double | Wander Angle |
| X | double | X coordinate |
| XBodyAccel | double | X Body Acceleration |
| XBodyAngRate | double | X Body Angle Rate |
| XVelocity | double | X Velocity |
| Y | double | Y coordinate |
| YBodyAccel | double | Y Body Acceleration |
| YBodyAngRate | double | Y Body Angle Rate |
| YVelocity | double | Y Velocity |
| Z | double | Z coordinate |
| ZBodyAccel | double | Z Body Acceleration |
| ZBodyAngRate | double | Z Body Angle Rate |
| ZVelocity | double | Z Velocity |