def replace_lossless(self, block, image_data):
"""
DefineBitsLossless, DefineBitsLossless2 を置き換える関数
画像を置き換える際に行うこと
1. lossless データの置き換え
2. ヘッダーの length の置き換え
3. tag block での length の置き換え
4. width, height, format データの置き換え
"""
tag_raw = block['value'][:2]
old_length = block['block_len'] # block['value'][2:6] と同じはず
image_id = le2byte(block['value'][6:8])
# format = ord(block['value'][8])
# 1.
g = Image2lossless(image_data, block['tag'])
fv_read = g.convert()
new_length = len(fv_read) + 7
# 2.
self.file_length += (new_length - old_length)
# 3.
block['block_len'] = new_length
# 4.
block['value'] = \
tag_raw + \
_h32(new_length) + \
_h16(image_id) + \
g.get_lossless_format() + \
_h16(g.width()) + \
_h16(g.height()) + \
fv_read
def write(self, f):
"swf 出力"
# ヘッダー長を書き換え
fl = _h32(self.file_length)
self.swf_head = self.swf_head[:4] + fl + self.swf_head[8:]
f.write(self.swf_head)
for block in self.swf_blocks:
f.write(block['value'])
f.write('\00\00')
def replace_jpeg(self, block, image_data):
"""
DefineBitsJPEG2 を置き換える関数
1. SWF ヘッダーの length の置き換え
2. tag block の書き換え
"""
assert image_data[:2] == '\xff\xd8' # JPEG SOI marker
tag_raw = block['value'][:2]
image_id = block['value'][6:8]
# 1.
old_length = block['block_len']
new_length = len(image_data) + 2
self.file_length += (new_length - old_length)
# 2.
block['block_len'] = new_length
block['value'] = \
tag_raw + \
_h32(new_length) + \
image_id + \
image_data
