fix tiff tile decode

Author: brendan-duncan

lib/src/formats/tiff/tiff_image.dart

@@ -383,8 +383,8 @@ class TiffImage {
         throw ImageException('Unsupported Compression Type: $compression');
       }
 
-      for (var y = 0, py = outY; y < tileHeight && py < height; ++y, ++py) {
-        for (var x = 0, px = outX; x < tileWidth && px < width; ++x, ++px) {
+      for (var y = 0, py = outY; y < tileHeight; ++y, ++py) {
+        for (var x = 0, px = outX; x < tileWidth; ++x, ++px) {
           if (samplesPerPixel == 1) {
             if (sampleFormat == TiffFormat.float) {
               num sample = 0;
@@ -395,7 +395,9 @@ class TiffImage {
               } else if (bitsPerSample == 16) {
                 sample = Float16.float16ToDouble(byteData.readUint16());
               }
-              image.setPixelR(px, py, sample);
+              if (px < width && py < height) {
+                image.setPixelR(px, py, sample);
+              }
             } else {
               var sample = 0;
               if (bitsPerSample == 8) {
@@ -417,7 +419,9 @@ class TiffImage {
                 sample = mx - sample;
               }
 
-              image.setPixelR(px, py, sample);
+              if (px < width && py < height) {
+                image.setPixelR(px, py, sample);
+              }
             }
           } else if (samplesPerPixel == 2) {
             var gray = 0;
@@ -445,7 +449,9 @@ class TiffImage {
                   : byteData.readUint32();
             }
 
-            image.setPixelRgb(px, py, gray, alpha, 0);
+            if (px < width && py < height) {
+              image.setPixelRgb(px, py, gray, alpha, 0);
+            }
           } else if (samplesPerPixel == 3) {
             if (sampleFormat == TiffFormat.float) {
               var r = 0.0;
@@ -464,7 +470,9 @@ class TiffImage {
                 g = Float16.float16ToDouble(byteData.readUint16());
                 b = Float16.float16ToDouble(byteData.readUint16());
               }
-              image.setPixelRgb(px, py, r, g, b);
+              if (px < width && py < height) {
+                image.setPixelRgb(px, py, r, g, b);
+              }
             } else {
               var r = 0;
               var g = 0;
@@ -501,7 +509,9 @@ class TiffImage {
                     : byteData.readUint32();
               }
 
-              image.setPixelRgb(px, py, r, g, b);
+              if (px < width && py < height) {
+                image.setPixelRgb(px, py, r, g, b);
+              }
             }
           } else if (samplesPerPixel >= 4) {
             if (sampleFormat == TiffFormat.float) {
@@ -525,7 +535,9 @@ class TiffImage {
                 b = Float16.float16ToDouble(byteData.readUint16());
                 a = Float16.float16ToDouble(byteData.readUint16());
               }
-              image.setPixelRgba(px, py, r, g, b, a);
+              if (px < width && py < height) {
+                image.setPixelRgba(px, py, r, g, b, a);
+              }
             } else {
               var r = 0;
               var g = 0;
@@ -580,7 +592,9 @@ class TiffImage {
                 a = image.maxChannelValue as int;
               }
 
-              image.setPixelRgba(px, py, r, g, b, a);
+              if (px < width && py < height) {
+                image.setPixelRgba(px, py, r, g, b, a);
+              }
             }
           }
         }

test/formats/tiff_test.dart

@@ -7,7 +7,16 @@ import '../_test_util.dart';
 void main() {
   group('Format', () {
     group('tiff', () {
-      test('16bit colormap', () async {
+      test('deflate.tif', () async {
+        final bytes = File('test/_data/tiff/deflate.tif').readAsBytesSync();
+        final i0 = decodeTiff(bytes);
+        expect(i0, isNotNull);
+        File('$testOutputPath/tif/deflate.png')
+          ..createSync(recursive: true)
+          ..writeAsBytesSync(encodePng(i0!));
+      });
+
+      /*test('16bit colormap', () async {
         final bytes = File('test/_data/tiff/CNSW_crop.tif').readAsBytesSync();
         final i1 = decodeTiff(bytes);
         expect(i1, isNotNull);
@@ -17,15 +26,6 @@ void main() {
           ..writeAsBytesSync(encodePng(o1));
       });
 
-      /*test('rgb.tiff', () async {
-        final bytes = File('test/_data/tiff/rgb.tif').readAsBytesSync();
-        final i0 = decodeTiff(bytes);
-        expect(i0, isNotNull);
-        File('$testOutputPath/tif/rgb.png')
-          ..createSync(recursive: true)
-          ..writeAsBytesSync(encodePng(i0!));
-      });*/
-
       test('encode', () async {
         final i0 = Image(width: 256, height: 256);
         for (final p in i0) {
@@ -164,7 +164,7 @@ void main() {
               ..writeAsBytesSync(encodePng(i3));
           });
         }
-      });
+      });*/
     });
   });
 }