diff --git a/scripts/scan_lz4.py b/scripts/scan_lz4.py
new file mode 100644
index 0000000..d2b4fb5
--- /dev/null
+++ b/scripts/scan_lz4.py
@@ -0,0 +1,82 @@
+# import mmap
+
+import struct
+
+LZ4_FRAME_MAGIC = b"\x04\x22\x4D\x18"
+
+
+def scan_legacy_lz4_frames(data):
+  LZ4_LEGACY_FRAME_MAGIC = b"\x02\x21\x4C\x18"
+  index = 0
+  while index < len(data):
+    try:
+      index = data.index(LZ4_LEGACY_FRAME_MAGIC, index)
+      print("Legacy Lz4 frame at {}".format(index))
+      index += 4
+      while index < len(data):
+        magic = data[index:index+4]
+        if magic == LZ4_LEGACY_FRAME_MAGIC or magic == LZ4_FRAME_MAGIC:
+          break
+        (csize,) = struct.unpack("<L", magic)
+        if index + 4 + csize >= len(data) or csize == 0:
+          break
+        print("Legacy lz4 block at {}, compressed data size {}".format(index, csize))
+        index += csize
+
+    except ValueError:
+      break
+
+
+def scan_lz4_frames(data):
+  index = 0
+  while index < len(data):
+    try:
+      index = data.index(LZ4_FRAME_MAGIC, index)
+      frame_offset = index
+      index += 4
+      flag = data[index]
+      block_descriptor = data[index+1]
+      block_checksum_present = flag & 0x10 != 0
+      content_size_present = flag & 0x8 != 0
+      content_checksum_present = flag & 0x4 != 0
+      dictionary_id = flag & 0x1 != 0
+      index += 2
+      content_size = None
+      if content_size_present:
+        content_size = struct.unpack("<Q", data[index:index+8])
+        index += 8
+      if dictionary_id:
+        dictionary_id = struct.unpack("<L", data[index:index+4])
+        index += 4
+      header_checksum = data[index:index+1]
+      index += 1
+      print("Lz4 frame at {}, content size: {}".format(
+          frame_offset, content_size))
+      while index < len(data):
+        (block_size,) = struct.unpack("<L", data[index:index+4])
+        uncompressed = block_size & 0x80000000 != 0
+        block_size &= 0x7FFFFFFF
+        index += 4
+        index += block_size
+        if index >= len(data) or block_size == 0:
+          break
+        print("Block uncompressed: {}, size: {}".format(uncompressed, block_size))
+    except ValueError:
+      break
+
+
+def main(argv):
+  if len(argv) != 2:
+    print("Usage:", argv[0], "<path to a file>")
+    return 1
+  path = argv[1]
+
+  with open(path, "rb") as fp:
+    data = fp.read()
+    scan_legacy_lz4_frames(data)
+    scan_lz4_frames(data)
+
+
+if __name__ == '__main__':
+  import sys
+  sys.exit(main(sys.argv))