public final int getNumber() {
    if (this == UNRECOGNIZED) {
      throw new java.lang.IllegalArgumentException(
          "Can't get the number of an unknown enum value.");
    }
    return value;
  }
<pre>
crossing_line annotation defines a polyline on top of the content from an
image/video based Vision AI stream, events happening across the line will
be captured. For example, the counts of people who goes acroos the line
in Occupancy Analytic Processor.
</pre>

<code>STREAM_ANNOTATION_TYPE_CROSSING_LINE = 2;</code>
java-visionai/proto-google-cloud-visionai-v1/src/main/java/com/google/cloud/visionai/v1/StreamAnnotationType.java