142 lines
3.8 KiB
Python
Executable File
142 lines
3.8 KiB
Python
Executable File
import struct
|
|
import zlib
|
|
|
|
LZMA_OK = True
|
|
|
|
try:
|
|
|
|
import pylzma as lzma
|
|
|
|
except:
|
|
|
|
try:
|
|
|
|
import lzma
|
|
|
|
except:
|
|
|
|
LZMA_OK = False
|
|
|
|
|
|
# hydrus_dev added ZWS support
|
|
|
|
def parse(input):
|
|
"""Parses the header information from an SWF file."""
|
|
if hasattr(input, 'read'):
|
|
input.seek(0)
|
|
else:
|
|
input = open(input, 'rb')
|
|
|
|
def read_ui8(c):
|
|
return struct.unpack('<B', c)[0]
|
|
|
|
def read_ui16(c):
|
|
return struct.unpack('<H', c)[0]
|
|
|
|
def read_ui32(c):
|
|
return struct.unpack('<I', c)[0]
|
|
|
|
header = {}
|
|
|
|
# Read the 3-byte signature field
|
|
signature = ''.join(struct.unpack('<3c', input.read(3)))
|
|
if signature not in ('FWS', 'CWS', 'ZWS'):
|
|
raise ValueError('Invalid SWF signature: %s' % signature)
|
|
|
|
# Compression
|
|
header['compressed'] = signature.startswith('C') or signature.startswith( 'Z' )
|
|
|
|
# Version
|
|
header['version'] = read_ui8(input.read(1))
|
|
|
|
# File size (stored as a 32-bit integer)
|
|
header['size'] = read_ui32(input.read(4))
|
|
|
|
# Payload
|
|
if signature.startswith( 'F' ):
|
|
|
|
buffer = input.read(header['size'])
|
|
|
|
elif signature.startswith( 'C' ):
|
|
buffer = input.read(header['size'])
|
|
# Unpack the zlib compression
|
|
buffer = zlib.decompress(buffer)
|
|
elif signature.startswith( 'Z' ):
|
|
|
|
uncompressed_size = input.read( 4 )
|
|
|
|
if LZMA_OK:
|
|
|
|
buffer = lzma.decompress( input.read() )
|
|
|
|
else:
|
|
|
|
raise Exception( 'LZMA library not available, so ZWS flash files cannot be parsed.' )
|
|
|
|
|
|
|
|
# Containing rectangle (struct RECT)
|
|
|
|
# The number of bits used to store the each of the RECT values are
|
|
# stored in first five bits of the first byte.
|
|
nbits = read_ui8(buffer[0]) >> 3
|
|
|
|
current_byte, buffer = read_ui8(buffer[0]), buffer[1:]
|
|
bit_cursor = 5
|
|
|
|
for item in 'xmin', 'xmax', 'ymin', 'ymax':
|
|
value = 0
|
|
for value_bit in range(nbits - 1, -1, -1): # == reversed(range(nbits))
|
|
if (current_byte << bit_cursor) & 0x80:
|
|
value |= 1 << value_bit
|
|
# Advance the bit cursor to the next bit
|
|
bit_cursor += 1
|
|
|
|
if bit_cursor > 7:
|
|
# We've exhausted the current byte, consume the next one
|
|
# from the buffer.
|
|
current_byte, buffer = read_ui8(buffer[0]), buffer[1:]
|
|
bit_cursor = 0
|
|
|
|
# Convert value from TWIPS to a pixel value
|
|
header[item] = value / 20
|
|
|
|
header['width'] = header['xmax'] - header['xmin']
|
|
header['height'] = header['ymax'] - header['ymin']
|
|
|
|
# Appendix A of the SWF specification states the following about the FPS
|
|
# field:
|
|
#
|
|
# [FPS] is supposed to be stored as a 16-bit integer, but the first
|
|
# byte (or last depending on how you look at it) is completely ignored.
|
|
#
|
|
# We handle this by parsing the value as UI16 and taking only the first
|
|
# byte as the value.
|
|
header['fps'] = read_ui16(buffer[0:2]) >> 8
|
|
header['frames'] = read_ui16(buffer[2:4])
|
|
|
|
input.close()
|
|
return header
|
|
|
|
|
|
def main():
|
|
import sys
|
|
|
|
if len(sys.argv) < 2:
|
|
print 'Usage: %s [SWF file]' % sys.argv[0]
|
|
sys.exit(1)
|
|
|
|
header = parse(sys.argv[1])
|
|
print 'SWF header'
|
|
print '----------'
|
|
print 'Version: %s' % header['version']
|
|
print 'Compression: %s' % header['compressed']
|
|
print 'Dimensions: %s x %s' % (header['width'], header['height'])
|
|
print 'Bounding box: (%s, %s, %s, %s)' % (header['xmin'], header['xmax'], header['ymin'], header['ymax'])
|
|
print 'Frames: %s' % header['frames']
|
|
print 'FPS: %s' % header['fps']
|
|
|
|
|
|
if __name__ == '__main__':
|
|
main()
|