diff --git a/minui/include/private/resources.h b/minui/include/private/resources.h
new file mode 100644
index 0000000..2a83a10
--- /dev/null
+++ b/minui/include/private/resources.h
@@ -0,0 +1,84 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <stdio.h>
+
+#include <memory>
+#include <string>
+
+#include <png.h>
+
+// This class handles the PNG file parsing. It also holds the ownership of the PNG pointer and the
+// opened file pointer. Both will be destroyed / closed when this object goes out of scope.
+class PngHandler {
+ public:
+  // Constructs an instance by loading the PNG file from '/res/images/<name>.png', or '<name>'.
+  PngHandler(const std::string& name);
+
+  ~PngHandler();
+
+  png_uint_32 width() const {
+    return width_;
+  }
+
+  png_uint_32 height() const {
+    return height_;
+  }
+
+  png_byte channels() const {
+    return channels_;
+  }
+
+  int bit_depth() const {
+    return bit_depth_;
+  }
+
+  int color_type() const {
+    return color_type_;
+  }
+
+  png_structp png_ptr() const {
+    return png_ptr_;
+  }
+
+  png_infop info_ptr() const {
+    return info_ptr_;
+  }
+
+  int error_code() const {
+    return error_code_;
+  };
+
+  operator bool() const {
+    return error_code_ == 0;
+  }
+
+ private:
+  png_structp png_ptr_{ nullptr };
+  png_infop info_ptr_{ nullptr };
+  png_uint_32 width_;
+  png_uint_32 height_;
+  png_byte channels_;
+  int bit_depth_;
+  int color_type_;
+
+  // The |error_code_| is set to a negative value if an error occurs when opening the png file.
+  int error_code_{ 0 };
+  // After initialization, we'll keep the file pointer open before destruction of PngHandler.
+  std::unique_ptr<FILE, decltype(&fclose)> png_fp_{ nullptr, fclose };
+};
diff --git a/minui/resources.cpp b/minui/resources.cpp
index 52ab60b..9f67cf8 100644
--- a/minui/resources.cpp
+++ b/minui/resources.cpp
@@ -14,6 +14,8 @@
  * limitations under the License.
  */
 
+#include "private/resources.h"
+
 #include <fcntl.h>
 #include <linux/fb.h>
 #include <linux/kd.h>
@@ -48,58 +50,13 @@
     return surface;
 }
 
-// This class handles the png file parsing. It also holds the ownership of the png pointer and the
-// opened file pointer. Both will be destroyed/closed when this object goes out of scope.
-class PngHandler {
- public:
-  PngHandler(const std::string& name);
-
-  ~PngHandler();
-
-  png_uint_32 width() const {
-    return width_;
-  }
-
-  png_uint_32 height() const {
-    return height_;
-  }
-
-  png_byte channels() const {
-    return channels_;
-  }
-
-  png_structp png_ptr() const {
-    return png_ptr_;
-  }
-
-  png_infop info_ptr() const {
-    return info_ptr_;
-  }
-
-  int error_code() const {
-    return error_code_;
-  };
-
-  operator bool() const {
-    return error_code_ == 0;
-  }
-
- private:
-  png_structp png_ptr_{ nullptr };
-  png_infop info_ptr_{ nullptr };
-  png_uint_32 width_;
-  png_uint_32 height_;
-  png_byte channels_;
-
-  // The |error_code_| is set to a negative value if an error occurs when opening the png file.
-  int error_code_;
-  // After initialization, we'll keep the file pointer open before destruction of PngHandler.
-  std::unique_ptr<FILE, decltype(&fclose)> png_fp_;
-};
-
-PngHandler::PngHandler(const std::string& name) : error_code_(0), png_fp_(nullptr, fclose) {
+PngHandler::PngHandler(const std::string& name) {
   std::string res_path = android::base::StringPrintf("/res/images/%s.png", name.c_str());
   png_fp_.reset(fopen(res_path.c_str(), "rbe"));
+  // Try to read from |name| if the resource path does not work.
+  if (!png_fp_) {
+    png_fp_.reset(fopen(name.c_str(), "rbe"));
+  }
   if (!png_fp_) {
     error_code_ = -1;
     return;
@@ -138,19 +95,17 @@
   png_set_sig_bytes(png_ptr_, sizeof(header));
   png_read_info(png_ptr_, info_ptr_);
 
-  int color_type;
-  int bit_depth;
-  png_get_IHDR(png_ptr_, info_ptr_, &width_, &height_, &bit_depth, &color_type, nullptr, nullptr,
+  png_get_IHDR(png_ptr_, info_ptr_, &width_, &height_, &bit_depth_, &color_type_, nullptr, nullptr,
                nullptr);
 
   channels_ = png_get_channels(png_ptr_, info_ptr_);
 
-  if (bit_depth == 8 && channels_ == 3 && color_type == PNG_COLOR_TYPE_RGB) {
+  if (bit_depth_ == 8 && channels_ == 3 && color_type_ == PNG_COLOR_TYPE_RGB) {
     // 8-bit RGB images: great, nothing to do.
-  } else if (bit_depth <= 8 && channels_ == 1 && color_type == PNG_COLOR_TYPE_GRAY) {
+  } else if (bit_depth_ <= 8 && channels_ == 1 && color_type_ == PNG_COLOR_TYPE_GRAY) {
     // 1-, 2-, 4-, or 8-bit gray images: expand to 8-bit gray.
     png_set_expand_gray_1_2_4_to_8(png_ptr_);
-  } else if (bit_depth <= 8 && channels_ == 1 && color_type == PNG_COLOR_TYPE_PALETTE) {
+  } else if (bit_depth_ <= 8 && channels_ == 1 && color_type_ == PNG_COLOR_TYPE_PALETTE) {
     // paletted images: expand to 8-bit RGB.  Note that we DON'T
     // currently expand the tRNS chunk (if any) to an alpha
     // channel, because minui doesn't support alpha channels in
@@ -158,8 +113,8 @@
     png_set_palette_to_rgb(png_ptr_);
     channels_ = 3;
   } else {
-    fprintf(stderr, "minui doesn't support PNG depth %d channels %d color_type %d\n", bit_depth,
-            channels_, color_type);
+    fprintf(stderr, "minui doesn't support PNG depth %d channels %d color_type %d\n", bit_depth_,
+            channels_, color_type_);
     error_code_ = -7;
   }
 }
diff --git a/tests/manual/recovery_test.cpp b/tests/manual/recovery_test.cpp
index 224ed5b..c992b07 100644
--- a/tests/manual/recovery_test.cpp
+++ b/tests/manual/recovery_test.cpp
@@ -15,10 +15,14 @@
  */
 
 #include <dirent.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 #include <sys/types.h>
 #include <unistd.h>
 
+#include <memory>
 #include <string>
 #include <vector>
 
@@ -26,13 +30,13 @@
 #include <android-base/strings.h>
 #include <android/log.h>
 #include <gtest/gtest.h>
-#include <png.h>
 #include <private/android_logger.h>
 
 #include "minui/minui.h"
+#include "private/resources.h"
 
-static const std::string myFilename = "/data/misc/recovery/inject.txt";
-static const std::string myContent = "Hello World\nWelcome to my recovery\n";
+static const std::string kInjectTxtFilename = "/data/misc/recovery/inject.txt";
+static const std::string kInjectTxtContent = "Hello World\nWelcome to my recovery\n";
 static const std::string kLocale = "zu";
 
 // Failure is expected on systems that do not deliver either the
@@ -43,9 +47,9 @@
                          const char *buf, size_t len, void *arg) {
   EXPECT_EQ(LOG_ID_SYSTEM, logId);
   EXPECT_EQ(ANDROID_LOG_INFO, prio);
-  EXPECT_NE(std::string::npos, myFilename.find(filename));
-  EXPECT_EQ(myContent, buf);
-  EXPECT_EQ(myContent.size(), len);
+  EXPECT_NE(std::string::npos, kInjectTxtFilename.find(filename));
+  EXPECT_EQ(kInjectTxtContent, buf);
+  EXPECT_EQ(kInjectTxtContent.size(), len);
   EXPECT_EQ(nullptr, arg);
   return len;
 }
@@ -58,13 +62,14 @@
   ssize_t ret = __android_log_pmsg_file_read(
       LOG_ID_SYSTEM, ANDROID_LOG_INFO, "recovery/", __pmsg_fn, nullptr);
   if (ret == -ENOENT) {
-    EXPECT_LT(0, __android_log_pmsg_file_write(LOG_ID_SYSTEM, ANDROID_LOG_INFO,
-        myFilename.c_str(), myContent.c_str(), myContent.size()));
+    EXPECT_LT(0, __android_log_pmsg_file_write(
+                     LOG_ID_SYSTEM, ANDROID_LOG_INFO, kInjectTxtFilename.c_str(),
+                     kInjectTxtContent.c_str(), kInjectTxtContent.size()));
 
-    fprintf(stderr, "injected test data, requires two intervening reboots "
-        "to check for replication\n");
+    fprintf(stderr,
+            "injected test data, requires two intervening reboots to check for replication\n");
   }
-  EXPECT_EQ(static_cast<ssize_t>(myContent.size()), ret);
+  EXPECT_EQ(static_cast<ssize_t>(kInjectTxtContent.size()), ret);
 }
 
 // recovery.persist - Requires recovery.inject, then a reboot, then
@@ -75,30 +80,26 @@
   ssize_t ret = __android_log_pmsg_file_read(
       LOG_ID_SYSTEM, ANDROID_LOG_INFO, "recovery/", __pmsg_fn, nullptr);
   if (ret == -ENOENT) {
-    EXPECT_LT(0, __android_log_pmsg_file_write(LOG_ID_SYSTEM, ANDROID_LOG_INFO,
-        myFilename.c_str(), myContent.c_str(), myContent.size()));
+    EXPECT_LT(0, __android_log_pmsg_file_write(
+                     LOG_ID_SYSTEM, ANDROID_LOG_INFO, kInjectTxtFilename.c_str(),
+                     kInjectTxtContent.c_str(), kInjectTxtContent.size()));
 
-    fprintf(stderr, "injected test data, requires intervening reboot "
-        "to check for storage\n");
+    fprintf(stderr, "injected test data, requires intervening reboot to check for storage\n");
   }
 
   std::string buf;
-  EXPECT_TRUE(android::base::ReadFileToString(myFilename, &buf));
-  EXPECT_EQ(myContent, buf);
-  if (access(myFilename.c_str(), F_OK) == 0) {
-    fprintf(stderr, "Removing persistent test data, "
-        "check if reconstructed on reboot\n");
+  EXPECT_TRUE(android::base::ReadFileToString(kInjectTxtFilename, &buf));
+  EXPECT_EQ(kInjectTxtContent, buf);
+  if (access(kInjectTxtFilename.c_str(), F_OK) == 0) {
+    fprintf(stderr, "Removing persistent test data, check if reconstructed on reboot\n");
   }
-  EXPECT_EQ(0, unlink(myFilename.c_str()));
+  EXPECT_EQ(0, unlink(kInjectTxtFilename.c_str()));
 }
 
-std::vector<std::string> image_dir {
-  "res-mdpi/images/",
-  "res-hdpi/images/",
-  "res-xhdpi/images/",
-  "res-xxhdpi/images/",
-  "res-xxxhdpi/images/"
-};
+static const std::vector<std::string> kResourceImagesDirs{ "res-mdpi/images/", "res-hdpi/images/",
+                                                           "res-xhdpi/images/",
+                                                           "res-xxhdpi/images/",
+                                                           "res-xxxhdpi/images/" };
 
 static int png_filter(const dirent* de) {
   if (de->d_type != DT_REG || !android::base::EndsWith(de->d_name, "_text.png")) {
@@ -107,12 +108,12 @@
   return 1;
 }
 
-// Find out all the PNG files to test, which stay under the same dir with the executable.
+// Finds out all the PNG files to test, which stay under the same dir with the executable.
 static std::vector<std::string> add_files() {
   std::string exec_dir = android::base::GetExecutableDirectory();
   std::vector<std::string> files;
-  for (const std::string& image : image_dir) {
-    std::string dir_path = exec_dir + "/" + image;
+  for (const std::string& images_dir : kResourceImagesDirs) {
+    std::string dir_path = exec_dir + "/" + images_dir;
     dirent** namelist;
     int n = scandir(dir_path.c_str(), &namelist, png_filter, alphasort);
     if (n == -1) {
@@ -133,71 +134,29 @@
   return files;
 }
 
-class ResourceTest : public testing::TestWithParam<std::string> {
+class ResourcesTest : public testing::TestWithParam<std::string> {
  public:
   static std::vector<std::string> png_list;
 
-  // Parse a png file and test if it's qualified for the background text image
-  // under recovery.
-  void SetUp() override {
-    std::string file_path = GetParam();
-    fp = fopen(file_path.c_str(), "rbe");
-    ASSERT_NE(nullptr, fp);
-
-    unsigned char header[8];
-    size_t bytesRead = fread(header, 1, sizeof(header), fp);
-    ASSERT_EQ(sizeof(header), bytesRead);
-    ASSERT_EQ(0, png_sig_cmp(header, 0, sizeof(header)));
-
-    png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, nullptr, nullptr, nullptr);
-    ASSERT_NE(nullptr, png_ptr);
-
-    info_ptr = png_create_info_struct(png_ptr);
-    ASSERT_NE(nullptr, info_ptr);
-
-    png_init_io(png_ptr, fp);
-    png_set_sig_bytes(png_ptr, sizeof(header));
-    png_read_info(png_ptr, info_ptr);
-
-    int color_type, bit_depth;
-    png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type, nullptr, nullptr,
-                 nullptr);
-    ASSERT_EQ(PNG_COLOR_TYPE_GRAY, color_type) << "Recovery expects grayscale PNG file.";
-    ASSERT_LT(static_cast<png_uint_32>(5), width);
-    ASSERT_LT(static_cast<png_uint_32>(0), height);
-    if (bit_depth <= 8) {
-      // 1-, 2-, 4-, or 8-bit gray images: expand to 8-bit gray.
-      png_set_expand_gray_1_2_4_to_8(png_ptr);
-    }
-
-    png_byte channels = png_get_channels(png_ptr, info_ptr);
-    ASSERT_EQ(1, channels) << "Recovery background text images expects 1-channel PNG file.";
-  }
-
-  void TearDown() override {
-    if (png_ptr != nullptr && info_ptr != nullptr) {
-      png_destroy_read_struct(&png_ptr, &info_ptr, nullptr);
-    }
-
-    if (fp != nullptr) {
-      fclose(fp);
-    }
-  }
-
  protected:
-  png_structp png_ptr;
-  png_infop info_ptr;
-  png_uint_32 width, height;
+  void SetUp() override {
+    png_ = std::make_unique<PngHandler>(GetParam());
+    ASSERT_TRUE(png_);
 
-  FILE* fp;
+    ASSERT_EQ(PNG_COLOR_TYPE_GRAY, png_->color_type()) << "Recovery expects grayscale PNG file.";
+    ASSERT_LT(static_cast<png_uint_32>(5), png_->width());
+    ASSERT_LT(static_cast<png_uint_32>(0), png_->height());
+    ASSERT_EQ(1, png_->channels()) << "Recovery background text images expects 1-channel PNG file.";
+  }
+
+  std::unique_ptr<PngHandler> png_{ nullptr };
 };
 
-std::vector<std::string> ResourceTest::png_list = add_files();
-
-TEST_P(ResourceTest, ValidateLocale) {
-  std::vector<unsigned char> row(width);
-  for (png_uint_32 y = 0; y < height; ++y) {
-    png_read_row(png_ptr, row.data(), nullptr);
+// Parses a png file and tests if it's qualified for the background text image under recovery.
+TEST_P(ResourcesTest, ValidateLocale) {
+  std::vector<unsigned char> row(png_->width());
+  for (png_uint_32 y = 0; y < png_->height(); ++y) {
+    png_read_row(png_->png_ptr(), row.data(), nullptr);
     int w = (row[1] << 8) | row[0];
     int h = (row[3] << 8) | row[2];
     int len = row[4];
@@ -206,19 +165,20 @@
     EXPECT_LT(0, len) << "Locale string should be non-empty.";
     EXPECT_NE(0, row[5]) << "Locale string is missing.";
 
-    ASSERT_GT(height, y + 1 + h) << "Locale: " << kLocale << " is not found in the file.";
+    ASSERT_GT(png_->height(), y + 1 + h) << "Locale: " << kLocale << " is not found in the file.";
     char* loc = reinterpret_cast<char*>(&row[5]);
     if (matches_locale(loc, kLocale.c_str())) {
       EXPECT_TRUE(android::base::StartsWith(loc, kLocale));
       break;
-    } else {
-      for (int i = 0; i < h; ++i, ++y) {
-        png_read_row(png_ptr, row.data(), nullptr);
-      }
+    }
+    for (int i = 0; i < h; ++i, ++y) {
+      png_read_row(png_->png_ptr(), row.data(), nullptr);
     }
   }
 }
 
-INSTANTIATE_TEST_CASE_P(BackgroundTextValidation, ResourceTest,
-                        ::testing::ValuesIn(ResourceTest::png_list.cbegin(),
-                                            ResourceTest::png_list.cend()));
+std::vector<std::string> ResourcesTest::png_list = add_files();
+
+INSTANTIATE_TEST_CASE_P(BackgroundTextValidation, ResourcesTest,
+                        ::testing::ValuesIn(ResourcesTest::png_list.cbegin(),
+                                            ResourcesTest::png_list.cend()));