Scala VOC parser. For Medium article

VocParser.scala

import scala.xml.Elem

object VocParser {

  def parse(xml: Elem): Voc = {
    val filename   = (xml \ "filename").text
    val objects    = xml \ "object"
    val vocObjects = objects.map(n => {
      val name = (n \ "name").text
      // VOC is 1-based index. Convert to 0 based.
      // See https://cv.gluon.ai/_modules/gluoncv/data/pascal_voc/detection.html#VOCDetection
      val xmin = (n \ "bndbox" \ "xmin").text.toInt - 1
      val ymin = (n \ "bndbox" \ "ymin").text.toInt - 1
      val xmax = (n \ "bndbox" \ "xmax").text.toInt - 1
      val ymax = (n \ "bndbox" \ "ymax").text.toInt - 1
      VocObject(name, xmin, ymin, xmax, ymax)
    });
    Voc(filename, objects = vocObjects)
  }

}