diff --git a/generate_image.gypi b/generate_image.gypi
deleted file mode 100644
index 025e925..0000000
--- a/generate_image.gypi
+++ /dev/null
@@ -1,27 +0,0 @@
-{
-  'variables': {
-    'out_dir': '<(SHARED_INTERMEDIATE_DIR)/<(image_out_dir)',
-    'generator': 'sample_images/generate_image.sh',
-  },
-  'rules': [
-    {
-      'rule_name': 'generate_image',
-      'extension': 'txt',
-      'inputs': [
-        '<(generator)',
-        '<(RULE_INPUT_PATH)',
-      ],
-      'outputs': [
-        '<(out_dir)/<(RULE_INPUT_ROOT).img',
-      ],
-      'action': [
-        '<(generator)',
-        '<(RULE_INPUT_PATH)',
-        '<(out_dir)',
-      ],
-      'msvs_cygwin_shell': 0,
-      'message': 'Generating image from <(RULE_INPUT_PATH)',
-      'process_outputs_as_sources': 1,
-    },
-  ],
-}
diff --git a/sample_images/disk_ext2_1k.txt b/sample_images/disk_ext2_1k.txt
deleted file mode 100644
index 1494535..0000000
--- a/sample_images/disk_ext2_1k.txt
+++ /dev/null
@@ -1 +0,0 @@
-default 16777216 1024
diff --git a/sample_images/disk_ext2_4k.txt b/sample_images/disk_ext2_4k.txt
deleted file mode 100644
index cac718f..0000000
--- a/sample_images/disk_ext2_4k.txt
+++ /dev/null
@@ -1 +0,0 @@
-default 16777216 4096
diff --git a/sample_images/disk_ext2_ue_settings.txt b/sample_images/disk_ext2_ue_settings.txt
deleted file mode 100644
index 554f7da..0000000
--- a/sample_images/disk_ext2_ue_settings.txt
+++ /dev/null
@@ -1 +0,0 @@
-ue_settings 16777216 4096
diff --git a/sample_images/generate_image.sh b/sample_images/generate_images.sh
similarity index 83%
rename from sample_images/generate_image.sh
rename to sample_images/generate_images.sh
index c4f132a..d8d92f5 100755
--- a/sample_images/generate_image.sh
+++ b/sample_images/generate_images.sh
@@ -4,6 +4,11 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+# This script generates some sample images used in unittests and packages them
+# in the sample_images.tar.bz2 file. The list of generated images and their
+# options are described in the main() function. You need to manually run this
+# script to update the generated images whenever you modify this script.
+
 set -e
 
 # cleanup <path>
@@ -145,14 +150,28 @@
   trap - INT TERM EXIT
 }
 
-image_desc="${1:-}"
-output_dir="${2:-}"
+OUTPUT_DIR=$(dirname "$0")
+IMAGES=()
 
-if [[ ! -e "${image_desc}" || ! -d "${output_dir}" ]]; then
-  echo "Use: $0 <image_description.txt> <output_dir>" >&2
-  exit 1
-fi
+# generate_image <image_name> [<image args> ...]
+generate_image() {
+  echo "Generating image $1.img"
+  IMAGES+=( "$1.img" )
+  generate_fs "${OUTPUT_DIR}/$1.img" "${@:2}"
+}
 
-args=( $(cat ${image_desc}) )
-dest_image="${output_dir}/$(basename ${image_desc} .txt).img"
-generate_fs "${dest_image}" "${args[@]}"
+main() {
+  # Add more sample images here.
+  generate_image disk_ext2_1k default 16777216 1024
+  generate_image disk_ext2_4k default 16777216 4096
+  generate_image disk_ext2_ue_settings ue_settings 16777216 4096
+
+  # Generate the tarball and delete temporary images.
+  echo "Packing tar file sample_images.tar.bz2"
+  tar -jcf "${OUTPUT_DIR}/sample_images.tar.bz2" -C "${OUTPUT_DIR}" \
+    "${IMAGES[@]}"
+  cd "${OUTPUT_DIR}"
+  rm "${IMAGES[@]}"
+}
+
+main
diff --git a/sample_images/sample_images.tar.bz2 b/sample_images/sample_images.tar.bz2
new file mode 100644
index 0000000..0982271
--- /dev/null
+++ b/sample_images/sample_images.tar.bz2
Binary files differ
diff --git a/tar_bunzip2.gypi b/tar_bunzip2.gypi
new file mode 100644
index 0000000..4ba7528
--- /dev/null
+++ b/tar_bunzip2.gypi
@@ -0,0 +1,27 @@
+{
+  'variables': {
+    'out_dir': '<(SHARED_INTERMEDIATE_DIR)/<(image_out_dir)',
+  },
+  'rules': [
+    {
+      'rule_name': 'tar-bunzip2',
+      'extension': 'bz2',
+      'inputs': [
+        '<(RULE_INPUT_PATH)',
+      ],
+      'outputs': [
+        # The .flag file is used to mark the timestamp of the file extraction
+        # and re-run this action if a new .bz2 file is generated.
+        '<(out_dir)/<(RULE_INPUT_ROOT).flag',
+      ],
+      'action': [
+        'sh',
+        '-c',
+        'tar -xvf "<(RULE_INPUT_PATH)" -C "<(out_dir)" && touch <(out_dir)/<(RULE_INPUT_ROOT).flag',
+      ],
+      'msvs_cygwin_shell': 0,
+      'process_outputs_as_sources': 1,
+      'message': 'Unpacking file <(RULE_INPUT_PATH)',
+    },
+  ],
+}
diff --git a/update_engine.gyp b/update_engine.gyp
index e339a4c..3a6714f 100644
--- a/update_engine.gyp
+++ b/update_engine.gyp
@@ -338,7 +338,7 @@
           ],
           'includes': ['../common-mk/openssl_pem.gypi'],
         },
-        # Sample images used for testing.
+        # Unpacks sample images used for testing.
         {
           'target_name': 'update_engine-test_images',
           'type': 'none',
@@ -346,11 +346,9 @@
             'image_out_dir': '.',
           },
           'sources': [
-            'sample_images/disk_ext2_1k.txt',
-            'sample_images/disk_ext2_4k.txt',
-            'sample_images/disk_ext2_ue_settings.txt',
+            'sample_images/sample_images.tar.bz2',
           ],
-          'includes': ['generate_image.gypi'],
+          'includes': ['tar_bunzip2.gypi'],
         },
         # Test HTTP Server.
         {