auto import from //depot/cupcake/@135843
diff --git a/tools/ota/convert-to-bmp.py b/tools/ota/convert-to-bmp.py
new file mode 100644
index 0000000..446c09d
--- /dev/null
+++ b/tools/ota/convert-to-bmp.py
@@ -0,0 +1,79 @@
+#!/usr/bin/python2.4
+
+"""A simple script to convert asset images to BMP files, that supports
+RGBA image."""
+
+import struct
+import Image
+import sys
+
+infile = sys.argv[1]
+outfile = sys.argv[2]
+
+if not outfile.endswith(".bmp"):
+ print >> sys.stderr, "Warning: I'm expecting to write BMP files."
+
+im = Image.open(infile)
+if im.mode == 'RGB':
+ im.save(outfile)
+elif im.mode == 'RGBA':
+ # Python Imaging Library doesn't write RGBA BMP files, so we roll
+ # our own.
+
+ BMP_HEADER_FMT = ("<" # little-endian
+ "H" # signature
+ "L" # file size
+ "HH" # reserved (set to 0)
+ "L" # offset to start of bitmap data)
+ )
+
+ BITMAPINFO_HEADER_FMT= ("<" # little-endian
+ "L" # size of this struct
+ "L" # width
+ "L" # height
+ "H" # planes (set to 1)
+ "H" # bit count
+ "L" # compression (set to 0 for minui)
+ "L" # size of image data (0 if uncompressed)
+ "L" # x pixels per meter (1)
+ "L" # y pixels per meter (1)
+ "L" # colors used (0)
+ "L" # important colors (0)
+ )
+
+ fileheadersize = struct.calcsize(BMP_HEADER_FMT)
+ infoheadersize = struct.calcsize(BITMAPINFO_HEADER_FMT)
+
+ header = struct.pack(BMP_HEADER_FMT,
+ 0x4d42, # "BM" in little-endian
+ (fileheadersize + infoheadersize +
+ im.size[0] * im.size[1] * 4),
+ 0, 0,
+ fileheadersize + infoheadersize)
+
+ info = struct.pack(BITMAPINFO_HEADER_FMT,
+ infoheadersize,
+ im.size[0],
+ im.size[1],
+ 1,
+ 32,
+ 0,
+ 0,
+ 1,
+ 1,
+ 0,
+ 0)
+
+ f = open(outfile, "wb")
+ f.write(header)
+ f.write(info)
+ data = im.tostring()
+ for j in range(im.size[1]-1, -1, -1): # rows bottom-to-top
+ for i in range(j*im.size[0]*4, (j+1)*im.size[0]*4, 4):
+ f.write(data[i+2]) # B
+ f.write(data[i+1]) # G
+ f.write(data[i+0]) # R
+ f.write(data[i+3]) # A
+ f.close()
+else:
+ print >> sys.stderr, "Don't know how to handle image mode '%s'." % (im.mode,)