LAS点云属性

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Field	Type	Description	Chinese Description	Remark
X	Double	X coordinate	X	The X, Y and Z values are stored as long integers. The X, Y and Z values are used in conjunction with the scale values and the offset values to determine the coordinate for each point as described in the Public Header Block section.
Y	Double	Y coordinate	Y
Z	Double	Z coordinate	Z
Intensity	Unsigned16	Representation of the pulse return magnitude.	强度： 代表脉冲返回的强度。	The intensity value is the integer representation of the pulse return magnitude. This value is optional and system specific. However, it should always be included if available. Intensity, when included, is always normalized to a 16 bit, unsigned value by multiplying the value by 65536/(intensity dynamic range of the sensor). For example, if the dynamic range of the sensor is 10 bits, the scaling value would be (65536/1024). If intensity is not included, this value must be set to zero. This normalization is required to ensure that data from different sensors can be correctly merged.
Amplitude	Float	This is the ratio of the received power to the power received at the detection limit expressed in dB.	振幅
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.	反射率
ReturnNumber	Unsigned8	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.	回波数	The Return Number is the pulse return number for a given output pulse. A given output laser pulse can have many returns, and they must be marked in sequence of return. The first return will have a Return Number of one, the second a Return Number of two, and so on up to fifteen returns. The Return Number must be between 1 and the Number of Returns, inclusive.
NumberOfReturns	Unsigned8	Total number of returns for a given pulse.	回波数量	The Number of Returns is the total number of returns for a given pulse. For example, a laser data point may be return two (Return Number) within a total number of fifteen returns.
ScanDirectionFlag	Unsigned8	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.	扫描方向：输出脉冲时扫描镜的行进方向。1为正方向，从轨道内方向的左侧向右侧移动；0为负方向，方向相反。	The Scan Direction Flag denotes the direction at which the scanner mirror was traveling at the time of the output pulse. A bit 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).
EdgeOfFlightLine	Unsigned8	Indicates the end of scan line before a direction change with a value of 1-0 otherwise.	航线边界	The Edge of Flight Line data bit has a value of 1 only when the point is at the edge of a scan. It is the last point on a given scan line before it changes direction or the mirror facet changes. Note that this field has no meaning for 360° Field of View scanners (such as Mobile LiDAR scanners) and should not be set.
Classification	Unsigned8	ASPRS classification, 0 for no classification. See LAS specification for details.	类别	This field represents the "class" attributes of a point. If a point has never been classified, this byte must be set to zero. The format for classification is a bit encoded field with the lower five bits used for the calss and the three high bits used for flags.
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.	扫描角度：输出的激光点角度，包括飞机的横滚角。扫描角度基于最低点，而-90则是飞机在飞行方向上的左侧。	The Scan Angle Rank is a signed one-byte with a valid range from -90 to +90. The Scan Angle Rank is the angle (rounded to the nearest integer in the absolute value sense) at which the laser point was output from the laser system including the roll of the aircraft. The scan angle is within 1 degree of accuracy from +90 to -90 degrees. The scan angle is an angel based on 0 degrees being nadir, and -90 degrees to the left side of the aircraft in the direction of flight.
UserData	Unsigned8	Unspecified user data.	用户数据：未指定的用户数据。	This field may be used at the user's discretion.
PointSourceId	Unsigned16	File source ID from which the point originated. Zero indicates that the point originated in the current file.	点源号	This value indicates the file from which this point originated. Valid values for this field are 1 to 65535 inclusive with zero being used for a special case discussed below. The numerical value corresponds to the File Source ID from which this point originated. Zero is reserved as a convenience to system implementers software should set the Point Source ID equal to the File Source ID of the file containing this point at some time during processing.
Red/Green/Blue	Unsigned16	Red/Green/Blue image channel value.	红/绿/蓝色通道值	The Red/Green/Blue image channel value associated with this point. The Red, Green, Blue values should always be normalized to 16 bit values. For example, when encoding an 8 bit per channel pixel, multiply each channel value by 256 prior to storage in these fields. This normalized allows color values from different camera bit depths to be accurately merged.
GpsTime	Double	GPS time that the point was acquired.	GPS时间	The GPS Time is the double floating point time tag value at which the point was acquired. It is GPS Week Time if the Global Encoding low bit is clear and Adjusted Standard GPS Time if the Global Encoding low bit is set.
InternalTime	Double	Scanner's internal time when the point was acquired, in seconds.	扫描器的内部时间
OffsetTime	Unsigned32	Milliseconds from first acquired point.	获取第一个点的毫秒数
IsPpsLocked	Unsigned8	The external PPS signal was found to be synchronized at the time of the current laser shot.	发现外部PPS信号在当前激光发射时已同步
StartPulse	Signed32	Relative pulse signal strength.	相对脉冲信号强度
ReflectedPulse	Signed32	Relative reflected pulse signal strength.	相对反射的脉冲信号强度
Pdop	Float	GPS PDOP (dilution of precision).	PDOP
Pitch	Float	Pitch in degrees.	横滚角
Roll	Float	Roll in degrees.	俯仰角
PulseWidth	Float	Laser received pulse width (digitizer samples).	激光接收的脉冲宽度（数字化样本）
Deviation	Float	A larger value for deviation indicates larger distortion.	偏差：大的偏差值代表大的失真。
PassiveSignal	Signed32	Relative passive signal.	无源信号：相对无源信号。
BackgroundRadiation	Float	A measure of background radiation.	背景辐射
PassiveX	Double	Passive X footprint.
PassiveY	Double	Passive Y footprint.
PassiveZ	Double	Passive Z footprint.
XVelocity	Double	X Velocity.	X 速度
YVelocity	Double	Y Velocity	Y 速度
ZVelocity	Double	Z Velocity.	Z 速度
Azimuth	Double	Scanner azimuth.	方位角：扫描器的方位角。
WanderAngle	Double	Wander Angle.	漂移角
XBodyAccel	Double	X Body Acceleration.	X 加速度
YBodyAccel	Double	Y Body Acceleration.	Y 加速度
ZBodyAccel	Double	Z Body Acceleration.	Z 加速度
XBodyAndRate	Double	X Body Angle Rate.	X 角速度
YBodyAndRate	Double	Y Body Angle Rate.	Y 角速度
ZBodyAndRate	Double	Z Body Angle Rate.	Z 角速度
Flag	Unsigned8	Flag
Mark	Unsigned8	Mark
Alpha	Unsigned16	Alpha
EchoRange	Double	Echo Range	回波幅度
ScanChannel	Unsigned8	Scan Channel	扫描频道	Scanner Channel is used to indicate the channel (scanner head) of a multi-channel system. Channel 0 is used for single scanner systems. Up to four channels are supported (0-3).
Infrared	Unsigned16	Infrared	红外的
HeightAboveGround	Double	Height Above Ground	与地面高差
ClassFlags	Unsigned8	Class Flags	类别标志
LvisLfid	Unsigned64	LVIS_LFID
ShotNumber	Unsigned64	Shot Number
LongitudeCentroid	Double	Longitude Centroid
LatitudeCentroid	Double	Latitude Centroid
ElevationCentroid	Double	Elevation Centroid
LongitudeLow	Double	Longitude Low
LatitudeLow	Double	Latitude Low
ElevationLow	Double	Elevation Low
LongitudeHigh	Double	Longitude High
LatitudeHigh	Double	Latitude High
ElevationHigh	Double	Elevation High
PointId	Unsigned32	An explicit representation of point ordering within a file, which allows this usually-implicit information to be preserved when reordering points.
OriginId	Unsigned32	A file source ID from which the point originated. This ID is global to a derivative dataset which may be aggregated from multiple files.
NormalX	Double	X component of a vector normal to surface at this point.	法向量的X分量
NormalY	Double	Y component of a vector normal to surface at this point.	法向量的Y分量
NormalZ	Double	Z component of a vector normal to surface at this point.	法向量的Z分量
Curvature	Double	Curvature of surface at this point.	曲率
Density	Double	Estimate of point density.	密度
Omit	Unsigned8	Used to shallowly mark a point as being omitted without removing it.	用于标记点而不删除。
NNDistance	Double	Distance metric related to a point's nearest neighbors.	最邻近距离