Autocrop not working when no changes #234

buildSrc/src/main/kotlin/Libs.kt

@@ -3,8 +3,7 @@ object Libs {
    const val kotlinVersion = "1.5.20"
 
    const val org = "com.sksamuel.scrimage"
-   const val CommonsIoVersion   = "2.11.0"
-   const val CommonsLangVersion = "3.11"
+
 
    object TwelveMonkeys {
       private const val Version = "3.7.0"
@@ -24,7 +23,7 @@ object Libs {
    }
 
    object Kotest {
-      private const val version = "4.6.1"
+      private const val version = "4.6.3"
       const val assertions = "io.kotest:kotest-assertions-core-jvm:$version"
       const val api = "io.kotest:kotest-framework-api:$version"
       const val junit5 = "io.kotest:kotest-runner-junit5-jvm:$version"
@@ -41,6 +40,8 @@ object Libs {
    }
 
    object Commons {
+      private const val CommonsIoVersion   = "2.11.0"
+      private const val CommonsLangVersion = "3.11"
       const val io   = "commons-io:commons-io:$CommonsIoVersion"
       const val lang = "org.apache.commons:commons-lang3:$CommonsLangVersion"
    }

scrimage-core/src/main/java/com/sksamuel/scrimage/AutocropOps.java

@@ -18,11 +18,11 @@ public static int scanright(Color color, int height, int width, int col, PixelsE
          return scanright(color, height, width, col + 1, f, tolerance);
    }
 
-   public static int scanleft(Color color, int height, int width, int col, PixelsExtractor f, int tolerance) {
+   public static int scanleft(Color color, int height, int col, PixelsExtractor f, int tolerance) {
       if (col == 0 || !PixelTools.colorMatches(color, tolerance, f.apply(new Rectangle(col, 0, 1, height))))
          return col;
       else
-         return scanleft(color, height, width, col - 1, f, tolerance);
+         return scanleft(color, height,  col - 1, f, tolerance);
    }
 
    public static int scandown(Color color, int height, int width, int row, PixelsExtractor f, int tolerance) {
@@ -32,10 +32,10 @@ public static int scandown(Color color, int height, int width, int row, PixelsEx
          return scandown(color, height, width, row + 1, f, tolerance);
    }
 
-   public static int scanup(Color color, int height, int width, int row, PixelsExtractor f, int tolerance) {
+   public static int scanup(Color color, int width, int row, PixelsExtractor f, int tolerance) {
       if (row == 0 || !PixelTools.colorMatches(color, tolerance, f.apply(new Rectangle(0, row, width, 1))))
          return row;
       else
-         return scanup(color, height, width, row - 1, f, tolerance);
+         return scanup(color, width, row - 1, f, tolerance);
    }
 }

scrimage-core/src/main/java/com/sksamuel/scrimage/ImmutableImage.java

@@ -40,7 +40,12 @@
 import org.apache.commons.io.IOUtils;
 import thirdparty.colorthief.ColorThief;
 import thirdparty.colorthief.MMCQ;
-import thirdparty.mortennobel.*;
+import thirdparty.mortennobel.BSplineFilter;
+import thirdparty.mortennobel.BiCubicFilter;
+import thirdparty.mortennobel.Lanczos3Filter;
+import thirdparty.mortennobel.ResampleFilters;
+import thirdparty.mortennobel.ResampleOp;
+import thirdparty.mortennobel.TriangleFilter;
 
 import javax.imageio.ImageIO;
 import java.awt.*;
@@ -410,9 +415,10 @@ public ImmutableImage autocrop(Color color) {
     */
    public ImmutableImage autocrop(Color color, int colorTolerance) {
       int x1 = AutocropOps.scanright(color, height, width, 0, pixelExtractor(), colorTolerance);
-      int x2 = AutocropOps.scanleft(color, height, width, width - 1, pixelExtractor(), colorTolerance);
+      int x2 = AutocropOps.scanleft(color, height, width - 1, pixelExtractor(), colorTolerance);
       int y1 = AutocropOps.scandown(color, height, width, 0, pixelExtractor(), colorTolerance);
-      int y2 = AutocropOps.scanup(color, height, width, height - 1, pixelExtractor(), colorTolerance);
+      int y2 = AutocropOps.scanup(color, width, height - 1, pixelExtractor(), colorTolerance);
+      if (x1 == 0 && y1 == 0 && x2 == width - 1 && y2 == height - 1) return this;
       return subimage(x1, y1, x2 - x1, y2 - y1);
    }
 

scrimage-tests/src/test/kotlin/com/sksamuel/scrimage/core/autocrop/AutoCropTest.kt

@@ -4,13 +4,22 @@ import com.sksamuel.scrimage.Dimension
 import com.sksamuel.scrimage.nio.ImmutableImageLoader
 import io.kotest.core.spec.style.FunSpec
 import io.kotest.matchers.shouldBe
+import io.kotest.matchers.types.shouldBeSameInstanceAs
+import java.awt.Color
 
 class AutoCropTest : FunSpec() {
    init {
+
       test("autocrop should work with transparent backgrounds") {
          val image = ImmutableImageLoader.create()
             .fromResource("/com/sksamuel/scrimage/core/autocrop/1b64a74b-ae2b-417e-a7db-b238e8ec5555.png")
          image.autocrop().dimensions() shouldBe Dimension(744, 1868)
       }
+
+      test("autocrop with no matching content should return the same image") {
+         val image = ImmutableImageLoader.create()
+            .fromResource("/com/sksamuel/scrimage/core/autocrop/1b64a74b-ae2b-417e-a7db-b238e8ec5555.png")
+         image.autocrop(Color.ORANGE).shouldBeSameInstanceAs(image)
+      }
    }
 }

scrimage-tests/src/test/kotlin/com/sksamuel/scrimage/core/autocrop/Issue234Test.kt

@@ -0,0 +1,15 @@
+package com.sksamuel.scrimage.core.autocrop
+
+import com.sksamuel.scrimage.ImmutableImage
+import io.kotest.core.spec.style.FunSpec
+import io.kotest.matchers.shouldBe
+import java.awt.Color
+
+class Issue234Test : FunSpec() {
+   init {
+      test("Autocrop not working properly when on small images #234") {
+         val input = ImmutableImage.loader().fromResource("/issue234.png")
+         input.autocrop(Color.green).dimensions() shouldBe input.dimensions()
+      }
+   }
+}