Scaleye

A scala wrapper for OpenCV using futures for parallel processing.

Installation

Scaleye is published at Maven Central. Use the following sbt snippet

libraryDependencies ++= Seq(
  "com.danielsanrocha" %% "scaleye" % "[version]"
)

Here a list of available versions for each scala version.

Scaleye Version	Scala Version
0.1.0	2.13

Sample Usages

Converting a image to grayscale

It is easy to realize simple images operations with scaleye

import com.danielsanrocha.scaleye.Image
import com.danielsanrocha.scaleye.transformers.ColorConverter

import scala.concurrent.Await
import scala.concurrent.duration._

object Main {
  val source = "./examples/images/flower.jpg"
  val outputFile = "./examples/output/grayscale.jpg"
  
  val img = Image.load(source)

  def main(args: Array[String]): Unit = {

    // All operations are realized inside a Future making it easy to parallelize tasks
    Await.ready(ColorConverter(img, ColorConverter.GRAYSCALE), 10.seconds)

    Image.save(img, outputFile)
  }
}

Extracting Lines and Drawing

The following code snippet show to execute sequential and parallel image processing tasks using scaleye.

The code load a image located at "./sudoku.jpg" then, sequentially, apply a ColorConverter, a ColorMask transformation and extracts lines using HoughLines algorithm; after that, it draws the extracted lines in the original image (in parallel) and write the created image at "./houghlines.jpg'.

import scala.concurrent.ExecutionContext.Implicits.global
import com.danielsanrocha.scaleye.{Color, Image}
import com.danielsanrocha.scaleye.extractors.HoughLines
import com.danielsanrocha.scaleye.transformers.{
  ColorConverter,
  ColorMask,
  Drawer
}

import scala.concurrent.{Await, Future}
import scala.concurrent.duration._

object Main {
  val source = "./sudoku.jpg"
  val outputFile = "./houghlines.jpg"

  val houghLinesDetector = new HoughLines(1, 3.14 / 180, 200, 160, 5)

  def main(args: Array[String]): Unit = {

    val img = Image.load(source.toString)
    val copy = img.clone()

    Await.ready(
      (for {
        _ <- ColorConverter(copy, ColorConverter.GRAYSCALE)
        _ <- ColorMask(copy, Color(0, 0, 0), Color(80, 80, 80))
        lines <- houghLinesDetector(copy)
      } yield {
        Future.sequence(lines map { line =>
          Drawer(img, line, Color.RED, 2)
        })
      }).flatten,
      10.seconds
    )

    Image.save(img, outputFile)
  }
}

Applying the above transformation for the image in "examples/images/sudoku.jpg" yields the following result:

Other examples can be found in the "examples/src/main/scala" folder in this repo.

Contributing

Any contribution is welcome =)

License

This project is licensed under the Apache 2.0 license - see the LICENSE file for details.

Contributors

Daniel Santana Rocha

danielsanrocha / scaleye 0.1.0