diff --git a/runtime/Android.mk b/runtime/Android.mk
index 74cc899..36c81fb 100644
--- a/runtime/Android.mk
+++ b/runtime/Android.mk
@@ -491,9 +491,9 @@
   LOCAL_C_INCLUDES += art
 
   ifeq ($$(art_static_or_shared),static)
-    LOCAL_STATIC_LIBRARIES := libnativehelper libnativebridge libsigchain_dummy libbacktrace
+    LOCAL_STATIC_LIBRARIES := libnativehelper libnativebridge libsigchain_dummy libbacktrace liblz4
   else
-    LOCAL_SHARED_LIBRARIES := libnativehelper libnativebridge libsigchain libbacktrace
+    LOCAL_SHARED_LIBRARIES := libnativehelper libnativebridge libsigchain libbacktrace liblz4
   endif
 
   ifeq ($$(art_target_or_host),target)
diff --git a/runtime/gc/collector/immune_spaces_test.cc b/runtime/gc/collector/immune_spaces_test.cc
index f741117..4884e66 100644
--- a/runtime/gc/collector/immune_spaces_test.cc
+++ b/runtime/gc/collector/immune_spaces_test.cc
@@ -113,7 +113,9 @@
         /*oat_data_end*/PointerToLowMemUInt32(map->End() + oat_size),
         /*oat_file_end*/PointerToLowMemUInt32(map->End() + oat_size),
         /*pointer_size*/sizeof(void*),
-        /*compile_pic*/false);
+        /*compile_pic*/false,
+        ImageHeader::kStorageModeUncompressed,
+        /*storage_size*/0u);
     return new DummyImageSpace(map.release(), live_bitmap.release());
   }
 };
diff --git a/runtime/gc/space/image_space.cc b/runtime/gc/space/image_space.cc
index e2b2431..8f67c21 100644
--- a/runtime/gc/space/image_space.cc
+++ b/runtime/gc/space/image_space.cc
@@ -17,12 +17,12 @@
 #include "image_space.h"
 
 #include <dirent.h>
+#include <lz4.h>
+#include <random>
 #include <sys/statvfs.h>
 #include <sys/types.h>
 #include <unistd.h>
 
-#include <random>
-
 #include "art_method.h"
 #include "base/macros.h"
 #include "base/stl_util.h"
@@ -677,11 +677,12 @@
     *error_msg = StringPrintf("Invalid image header in '%s'", image_filename);
     return nullptr;
   }
-  // Check that the file is large enough.
-  uint64_t image_file_size = static_cast<uint64_t>(file->GetLength());
-  if (image_header.GetImageSize() > image_file_size) {
-    *error_msg = StringPrintf("Image file too small for image heap: %" PRIu64 " vs. %zu.",
-                              image_file_size, image_header.GetImageSize());
+  // Check that the file is larger or equal to the header size + data size.
+  const uint64_t image_file_size = static_cast<uint64_t>(file->GetLength());
+  if (image_file_size < sizeof(ImageHeader) + image_header.GetDataSize()) {
+    *error_msg = StringPrintf("Image file truncated: %" PRIu64 " vs. %" PRIu64 ".",
+                              image_file_size,
+                              image_header.GetDataSize());
     return nullptr;
   }
 
@@ -697,7 +698,11 @@
   }
 
   const auto& bitmap_section = image_header.GetImageSection(ImageHeader::kSectionImageBitmap);
-  auto end_of_bitmap = static_cast<size_t>(bitmap_section.End());
+  // The location we want to map from is the first aligned page after the end of the stored
+  // (possibly compressed) data.
+  const size_t image_bitmap_offset = RoundUp(sizeof(image_header) + image_header.GetDataSize(),
+                                             kPageSize);
+  const size_t end_of_bitmap = image_bitmap_offset + bitmap_section.Size();
   if (end_of_bitmap != image_file_size) {
     *error_msg = StringPrintf(
         "Image file size does not equal end of bitmap: size=%" PRIu64 " vs. %zu.", image_file_size,
@@ -706,16 +711,60 @@
   }
 
   // Note: The image header is part of the image due to mmap page alignment required of offset.
-  std::unique_ptr<MemMap> map(MemMap::MapFileAtAddress(image_header.GetImageBegin(),
-                                                       image_header.GetImageSize(),
-                                                       PROT_READ | PROT_WRITE,
+  std::unique_ptr<MemMap> map;
+  if (image_header.GetStorageMode() == ImageHeader::kStorageModeUncompressed) {
+    map.reset(MemMap::MapFileAtAddress(image_header.GetImageBegin(),
+                                       image_header.GetImageSize(),
+                                       PROT_READ | PROT_WRITE,
+                                       MAP_PRIVATE,
+                                       file->Fd(),
+                                       0,
+                                       /*low_4gb*/false,
+                                       /*reuse*/false,
+                                       image_filename,
+                                       error_msg));
+  } else {
+    // Reserve output and decompress into it.
+    map.reset(MemMap::MapAnonymous(image_location,
+                                   image_header.GetImageBegin(),
+                                   image_header.GetImageSize(),
+                                   PROT_READ | PROT_WRITE,
+                                   /*low_4gb*/false,
+                                   /*reuse*/false,
+                                   error_msg));
+    if (map != nullptr) {
+      const size_t stored_size = image_header.GetDataSize();
+      const size_t write_offset = sizeof(image_header);  // Skip the header.
+      std::unique_ptr<MemMap> temp_map(MemMap::MapFile(sizeof(ImageHeader) + stored_size,
+                                                       PROT_READ,
                                                        MAP_PRIVATE,
                                                        file->Fd(),
-                                                       0,
+                                                       /*offset*/0,
                                                        /*low_4gb*/false,
-                                                       /*reuse*/false,
                                                        image_filename,
                                                        error_msg));
+      if (temp_map == nullptr) {
+        DCHECK(!error_msg->empty());
+        return nullptr;
+      }
+      memcpy(map->Begin(), &image_header, sizeof(image_header));
+      const uint64_t start = NanoTime();
+      const size_t decompressed_size = LZ4_decompress_safe(
+          reinterpret_cast<char*>(temp_map->Begin()) + sizeof(ImageHeader),
+          reinterpret_cast<char*>(map->Begin()) + write_offset,
+          stored_size,
+          map->Size());
+      // TODO: VLOG(image)
+      VLOG(class_linker) << "Decompressing image took " << PrettyDuration(NanoTime() - start);
+      if (decompressed_size + sizeof(ImageHeader) != image_header.GetImageSize()) {
+        *error_msg = StringPrintf("Decompressed size does not match expected image size %zu vs %zu",
+                                  decompressed_size + sizeof(ImageHeader),
+                                  image_header.GetImageSize());
+        return nullptr;
+      }
+    }
+  }
+
   if (map == nullptr) {
     DCHECK(!error_msg->empty());
     return nullptr;
@@ -723,16 +772,16 @@
   CHECK_EQ(image_header.GetImageBegin(), map->Begin());
   DCHECK_EQ(0, memcmp(&image_header, map->Begin(), sizeof(ImageHeader)));
 
-  std::unique_ptr<MemMap> image_map(MemMap::MapFileAtAddress(nullptr,
-                                                             bitmap_section.Size(),
-                                                             PROT_READ, MAP_PRIVATE,
-                                                             file->Fd(),
-                                                             bitmap_section.Offset(),
-                                                             /*low_4gb*/false,
-                                                             /*reuse*/false,
-                                                             image_filename,
-                                                             error_msg));
-  if (image_map.get() == nullptr) {
+  std::unique_ptr<MemMap> image_bitmap_map(MemMap::MapFileAtAddress(nullptr,
+                                                                    bitmap_section.Size(),
+                                                                    PROT_READ, MAP_PRIVATE,
+                                                                    file->Fd(),
+                                                                    image_bitmap_offset,
+                                                                    /*low_4gb*/false,
+                                                                    /*reuse*/false,
+                                                                    image_filename,
+                                                                    error_msg));
+  if (image_bitmap_map == nullptr) {
     *error_msg = StringPrintf("Failed to map image bitmap: %s", error_msg->c_str());
     return nullptr;
   }
@@ -741,9 +790,11 @@
                                        bitmap_index));
   std::unique_ptr<accounting::ContinuousSpaceBitmap> bitmap(
       accounting::ContinuousSpaceBitmap::CreateFromMemMap(
-          bitmap_name, image_map.release(), reinterpret_cast<uint8_t*>(map->Begin()),
+          bitmap_name,
+          image_bitmap_map.release(),
+          reinterpret_cast<uint8_t*>(map->Begin()),
           accounting::ContinuousSpaceBitmap::ComputeHeapSize(bitmap_section.Size())));
-  if (bitmap.get() == nullptr) {
+  if (bitmap == nullptr) {
     *error_msg = StringPrintf("Could not create bitmap '%s'", bitmap_name.c_str());
     return nullptr;
   }
diff --git a/runtime/image.cc b/runtime/image.cc
index 2eac3fb..7d2ef75 100644
--- a/runtime/image.cc
+++ b/runtime/image.cc
@@ -24,7 +24,7 @@
 namespace art {
 
 const uint8_t ImageHeader::kImageMagic[] = { 'a', 'r', 't', '\n' };
-const uint8_t ImageHeader::kImageVersion[] = { '0', '2', '3', '\0' };
+const uint8_t ImageHeader::kImageVersion[] = { '0', '2', '4', '\0' };
 
 ImageHeader::ImageHeader(uint32_t image_begin,
                          uint32_t image_size,
@@ -36,7 +36,9 @@
                          uint32_t oat_data_end,
                          uint32_t oat_file_end,
                          uint32_t pointer_size,
-                         bool compile_pic)
+                         bool compile_pic,
+                         StorageMode storage_mode,
+                         size_t data_size)
   : image_begin_(image_begin),
     image_size_(image_size),
     oat_checksum_(oat_checksum),
@@ -47,7 +49,9 @@
     patch_delta_(0),
     image_roots_(image_roots),
     pointer_size_(pointer_size),
-    compile_pic_(compile_pic) {
+    compile_pic_(compile_pic),
+    storage_mode_(storage_mode),
+    data_size_(data_size) {
   CHECK_EQ(image_begin, RoundUp(image_begin, kPageSize));
   CHECK_EQ(oat_file_begin, RoundUp(oat_file_begin, kPageSize));
   CHECK_EQ(oat_data_begin, RoundUp(oat_data_begin, kPageSize));
diff --git a/runtime/image.h b/runtime/image.h
index a16f3c9..3032beb 100644
--- a/runtime/image.h
+++ b/runtime/image.h
@@ -78,10 +78,27 @@
 // header of image files written by ImageWriter, read and validated by Space.
 class PACKED(4) ImageHeader {
  public:
+  enum StorageMode : uint32_t {
+    kStorageModeUncompressed,
+    kStorageModeLZ4,
+    kStorageModeCount,  // Number of elements in enum.
+  };
+  static constexpr StorageMode kDefaultStorageMode = kStorageModeUncompressed;
+
   ImageHeader()
-      : image_begin_(0U), image_size_(0U), oat_checksum_(0U), oat_file_begin_(0U),
-        oat_data_begin_(0U), oat_data_end_(0U), oat_file_end_(0U), patch_delta_(0),
-        image_roots_(0U), pointer_size_(0U), compile_pic_(0) {}
+      : image_begin_(0U),
+        image_size_(0U),
+        oat_checksum_(0U),
+        oat_file_begin_(0U),
+        oat_data_begin_(0U),
+        oat_data_end_(0U),
+        oat_file_end_(0U),
+        patch_delta_(0),
+        image_roots_(0U),
+        pointer_size_(0U),
+        compile_pic_(0),
+        storage_mode_(kDefaultStorageMode),
+        data_size_(0) {}
 
   ImageHeader(uint32_t image_begin,
               uint32_t image_size,
@@ -93,7 +110,9 @@
               uint32_t oat_data_end,
               uint32_t oat_file_end,
               uint32_t pointer_size,
-              bool compile_pic);
+              bool compile_pic,
+              StorageMode storage_mode,
+              size_t data_size);
 
   bool IsValid() const;
   const char* GetMagic() const;
@@ -194,6 +213,14 @@
     return compile_pic_ != 0;
   }
 
+  StorageMode GetStorageMode() const {
+    return storage_mode_;
+  }
+
+  uint64_t GetDataSize() const {
+    return data_size_;
+  }
+
  private:
   static const uint8_t kImageMagic[4];
   static const uint8_t kImageVersion[4];
@@ -241,6 +268,13 @@
   // Image methods.
   uint64_t image_methods_[kImageMethodsCount];
 
+  // Storage method for the image, the image may be compressed.
+  StorageMode storage_mode_;
+
+  // Data size for the image data excluding the bitmap and the header. For compressed images, this
+  // is the compressed size in the file.
+  uint32_t data_size_;
+
   friend class ImageWriter;
 };
 
@@ -248,6 +282,7 @@
 std::ostream& operator<<(std::ostream& os, const ImageHeader::ImageRoot& policy);
 std::ostream& operator<<(std::ostream& os, const ImageHeader::ImageSections& section);
 std::ostream& operator<<(std::ostream& os, const ImageSection& section);
+std::ostream& operator<<(std::ostream& os, const ImageHeader::StorageMode& mode);
 
 }  // namespace art