M7350/bootable/recovery/tools/ota/convert-to-bmp.py
2024-09-09 08:52:07 +00:00

80 lines
2.5 KiB
Python

#!/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,)