diff --git a/tests/include/helpers.cc b/tests/include/helpers.cc
index a0cd158..16eedee 100644
--- a/tests/include/helpers.cc
+++ b/tests/include/helpers.cc
@@ -437,10 +437,13 @@
   ArgbBuffer buffer(WP2_Argb_32);
   if (image.format() == buffer.format()) {
     WP2_ASSERT_STATUS(buffer.SetView(image));
+    if (rect.GetArea() != 0) WP2_ASSERT_STATUS(buffer.SetView(buffer, rect));
   } else {
-    WP2_ASSERT_STATUS(buffer.ConvertFrom(image));
+    ArgbBuffer cropped_image(image.format());
+    WP2_ASSERT_STATUS(cropped_image.SetView(
+        image, rect.GetArea() != 0 ? rect : image.AsRect()));
+    WP2_ASSERT_STATUS(buffer.ConvertFrom(cropped_image));
   }
-  if (rect.GetArea() != 0) WP2_ASSERT_STATUS(buffer.SetView(buffer, rect));
   WP2_ASSERT_STATUS(SaveImage(buffer, file_path.c_str(), /*overwrite=*/true));
 }
 
diff --git a/tests/include/helpers_incr.cc b/tests/include/helpers_incr.cc
index bca2001..f377a5c 100644
--- a/tests/include/helpers_incr.cc
+++ b/tests/include/helpers_incr.cc
@@ -378,7 +378,7 @@
       if (i > 0) {
         size_t previous_offset, previous_length;
         CHECK_OR_DIE(idec.TryGetFrameLocation(i - 1, &previous_offset,
-                                                  &previous_length));
+                                              &previous_length));
         CHECK_OR_DIE(offset == previous_offset + previous_length);
       }
     }
@@ -443,8 +443,9 @@
       if (has_true_incremental_output_) {
         // Arbitrary formula. There is no theoritical maximum threshold but in
         // practice it is unlikely to go beyond this one.
-        const uint32_t max_num_block_rows_in_two_bytes =
-            std::max(1u, kMinBlockSizePix * kMaxBlockSizePix / features->width);
+        const uint32_t max_num_block_rows_in_two_bytes = std::max(
+            1u, kMinBlockSizePix * kMaxBlockSizePix /
+                    (is_sideways ? features->height : features->width));
         max_num_lines = kMaxBlockSizePix * max_num_block_rows_in_two_bytes;
       } else {
         max_num_lines = features->tile_height;