runlength_featuresrunlength_featuresRunlengthFeaturesRunlengthFeaturesrunlength_features (算子)

名称

runlength_featuresrunlength_featuresRunlengthFeaturesRunlengthFeaturesrunlength_features — 区域游程编码的特征值。

签名

描述

算子 runlength_featuresrunlength_featuresRunlengthFeaturesRunlengthFeaturesRunlengthFeaturesrunlength_features calculates for every input region from RegionsRegionsRegionsRegionsregionsregions the number of runs necessary for storing this region with the aid of runlength coding. Furthermore the so-called “K-factor” is determined, which indicates by how much the number of runs differs from the ideal of the square in which this value is 1.0.

The K-factor (KFactorKFactorKFactorKFactorKFactorkfactor) is calculated according to the formula: wherein Area indicates the area of the region. It should be noted that the K-factor can be smaller than 1.0 (in case of long horizontal regions).

The L-factor (LFactorLFactorLFactorLFactorLFactorlfactor) indicates the mean number of runs for each line index occurring in the region.

MeanLengthMeanLengthMeanLengthMeanLengthmeanLengthmean_length indicates the mean length of the runs. The parameter BytesBytesBytesBytesbytesbytes indicates how many bytes are necessary for coding the region with runlengths.

注意

All features calculated by the operator runlength_featuresrunlength_featuresRunlengthFeaturesRunlengthFeaturesRunlengthFeaturesrunlength_features are not rotation invariant because the runlength coding depends on the direction. The operator runlength_featuresrunlength_featuresRunlengthFeaturesRunlengthFeaturesRunlengthFeaturesrunlength_features does not serve for calculating shape features but for controlling and analyzing the efficiency of the runlength coding.

执行信息

• 多线程类型：可重入（与非独占算子并行运行）。
• 多线程作用域：全局（可从任何线程调用）。
• 在元组级别上自动并行化。

参数

复杂度

The mean runtime complexity is O(1).

结果

算子 runlength_featuresrunlength_featuresRunlengthFeaturesRunlengthFeaturesRunlengthFeaturesrunlength_features 返回值 2 ( H_MSG_TRUE) if the input is not empty。如有必要，则抛出异常。

可能的前趋

thresholdthresholdThresholdThresholdThresholdthreshold, regiongrowingregiongrowingRegiongrowingRegiongrowingRegiongrowingregiongrowing, connectionconnectionConnectionConnectionConnectionconnection

另见

runlength_distributionrunlength_distributionRunlengthDistributionRunlengthDistributionRunlengthDistributionrunlength_distribution

模块

基础