You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
477 lines
15 KiB
477 lines
15 KiB
5 months ago
|
"""
|
||
|
|
Blizzard Mipmap Format (.blp)
|
||
|
|
Jerome Leclanche <jerome@leclan.ch>
|
||
|
|
|
||
|
|
The contents of this file are hereby released in the public domain (CC0)
|
||
|
|
Full text of the CC0 license:
|
||
|
|
https://creativecommons.org/publicdomain/zero/1.0/
|
||
|
|
|
||
|
|
BLP1 files, used mostly in Warcraft III, are not fully supported.
|
||
|
|
All types of BLP2 files used in World of Warcraft are supported.
|
||
|
|
|
||
|
|
The BLP file structure consists of a header, up to 16 mipmaps of the
|
||
|
|
texture
|
||
|
|
|
||
|
|
Texture sizes must be powers of two, though the two dimensions do
|
||
|
|
not have to be equal; 512x256 is valid, but 512x200 is not.
|
||
|
|
The first mipmap (mipmap #0) is the full size image; each subsequent
|
||
|
|
mipmap halves both dimensions. The final mipmap should be 1x1.
|
||
|
|
|
||
|
|
BLP files come in many different flavours:
|
||
|
|
* JPEG-compressed (type == 0) - only supported for BLP1.
|
||
|
|
* RAW images (type == 1, encoding == 1). Each mipmap is stored as an
|
||
|
|
array of 8-bit values, one per pixel, left to right, top to bottom.
|
||
|
|
Each value is an index to the palette.
|
||
|
|
* DXT-compressed (type == 1, encoding == 2):
|
||
|
|
- DXT1 compression is used if alpha_encoding == 0.
|
||
|
|
- An additional alpha bit is used if alpha_depth == 1.
|
||
|
|
- DXT3 compression is used if alpha_encoding == 1.
|
||
|
|
- DXT5 compression is used if alpha_encoding == 7.
|
||
|
|
"""
|
||
|
|
|
||
|
|
from __future__ import annotations
|
||
|
|
|
||
|
|
import os
|
||
|
|
import struct
|
||
|
|
from enum import IntEnum
|
||
|
|
from io import BytesIO
|
||
|
|
|
||
|
|
from . import Image, ImageFile
|
||
|
|
|
||
|
|
|
||
|
|
class Format(IntEnum):
|
||
|
|
JPEG = 0
|
||
|
|
|
||
|
|
|
||
|
|
class Encoding(IntEnum):
|
||
|
|
UNCOMPRESSED = 1
|
||
|
|
DXT = 2
|
||
|
|
UNCOMPRESSED_RAW_BGRA = 3
|
||
|
|
|
||
|
|
|
||
|
|
class AlphaEncoding(IntEnum):
|
||
|
|
DXT1 = 0
|
||
|
|
DXT3 = 1
|
||
|
|
DXT5 = 7
|
||
|
|
|
||
|
|
|
||
|
|
def unpack_565(i):
|
||
|
|
return ((i >> 11) & 0x1F) << 3, ((i >> 5) & 0x3F) << 2, (i & 0x1F) << 3
|
||
|
|
|
||
|
|
|
||
|
|
def decode_dxt1(data, alpha=False):
|
||
|
|
"""
|
||
|
|
input: one "row" of data (i.e. will produce 4*width pixels)
|
||
|
|
"""
|
||
|
|
|
||
|
|
blocks = len(data) // 8 # number of blocks in row
|
||
|
|
ret = (bytearray(), bytearray(), bytearray(), bytearray())
|
||
|
|
|
||
|
|
for block in range(blocks):
|
||
|
|
# Decode next 8-byte block.
|
||
|
|
idx = block * 8
|
||
|
|
color0, color1, bits = struct.unpack_from("<HHI", data, idx)
|
||
|
|
|
||
|
|
r0, g0, b0 = unpack_565(color0)
|
||
|
|
r1, g1, b1 = unpack_565(color1)
|
||
|
|
|
||
|
|
# Decode this block into 4x4 pixels
|
||
|
|
# Accumulate the results onto our 4 row accumulators
|
||
|
|
for j in range(4):
|
||
|
|
for i in range(4):
|
||
|
|
# get next control op and generate a pixel
|
||
|
|
|
||
|
|
control = bits & 3
|
||
|
|
bits = bits >> 2
|
||
|
|
|
||
|
|
a = 0xFF
|
||
|
|
if control == 0:
|
||
|
|
r, g, b = r0, g0, b0
|
||
|
|
elif control == 1:
|
||
|
|
r, g, b = r1, g1, b1
|
||
|
|
elif control == 2:
|
||
|
|
if color0 > color1:
|
||
|
|
r = (2 * r0 + r1) // 3
|
||
|
|
g = (2 * g0 + g1) // 3
|
||
|
|
b = (2 * b0 + b1) // 3
|
||
|
|
else:
|
||
|
|
r = (r0 + r1) // 2
|
||
|
|
g = (g0 + g1) // 2
|
||
|
|
b = (b0 + b1) // 2
|
||
|
|
elif control == 3:
|
||
|
|
if color0 > color1:
|
||
|
|
r = (2 * r1 + r0) // 3
|
||
|
|
g = (2 * g1 + g0) // 3
|
||
|
|
b = (2 * b1 + b0) // 3
|
||
|
|
else:
|
||
|
|
r, g, b, a = 0, 0, 0, 0
|
||
|
|
|
||
|
|
if alpha:
|
||
|
|
ret[j].extend([r, g, b, a])
|
||
|
|
else:
|
||
|
|
ret[j].extend([r, g, b])
|
||
|
|
|
||
|
|
return ret
|
||
|
|
|
||
|
|
|
||
|
|
def decode_dxt3(data):
|
||
|
|
"""
|
||
|
|
input: one "row" of data (i.e. will produce 4*width pixels)
|
||
|
|
"""
|
||
|
|
|
||
|
|
blocks = len(data) // 16 # number of blocks in row
|
||
|
|
ret = (bytearray(), bytearray(), bytearray(), bytearray())
|
||
|
|
|
||
|
|
for block in range(blocks):
|
||
|
|
idx = block * 16
|
||
|
|
block = data[idx : idx + 16]
|
||
|
|
# Decode next 16-byte block.
|
||
|
|
bits = struct.unpack_from("<8B", block)
|
||
|
|
color0, color1 = struct.unpack_from("<HH", block, 8)
|
||
|
|
|
||
|
|
(code,) = struct.unpack_from("<I", block, 12)
|
||
|
|
|
||
|
|
r0, g0, b0 = unpack_565(color0)
|
||
|
|
r1, g1, b1 = unpack_565(color1)
|
||
|
|
|
||
|
|
for j in range(4):
|
||
|
|
high = False # Do we want the higher bits?
|
||
|
|
for i in range(4):
|
||
|
|
alphacode_index = (4 * j + i) // 2
|
||
|
|
a = bits[alphacode_index]
|
||
|
|
if high:
|
||
|
|
high = False
|
||
|
|
a >>= 4
|
||
|
|
else:
|
||
|
|
high = True
|
||
|
|
a &= 0xF
|
||
|
|
a *= 17 # We get a value between 0 and 15
|
||
|
|
|
||
|
|
color_code = (code >> 2 * (4 * j + i)) & 0x03
|
||
|
|
|
||
|
|
if color_code == 0:
|
||
|
|
r, g, b = r0, g0, b0
|
||
|
|
elif color_code == 1:
|
||
|
|
r, g, b = r1, g1, b1
|
||
|
|
elif color_code == 2:
|
||
|
|
r = (2 * r0 + r1) // 3
|
||
|
|
g = (2 * g0 + g1) // 3
|
||
|
|
b = (2 * b0 + b1) // 3
|
||
|
|
elif color_code == 3:
|
||
|
|
r = (2 * r1 + r0) // 3
|
||
|
|
g = (2 * g1 + g0) // 3
|
||
|
|
b = (2 * b1 + b0) // 3
|
||
|
|
|
||
|
|
ret[j].extend([r, g, b, a])
|
||
|
|
|
||
|
|
return ret
|
||
|
|
|
||
|
|
|
||
|
|
def decode_dxt5(data):
|
||
|
|
"""
|
||
|
|
input: one "row" of data (i.e. will produce 4 * width pixels)
|
||
|
|
"""
|
||
|
|
|
||
|
|
blocks = len(data) // 16 # number of blocks in row
|
||
|
|
ret = (bytearray(), bytearray(), bytearray(), bytearray())
|
||
|
|
|
||
|
|
for block in range(blocks):
|
||
|
|
idx = block * 16
|
||
|
|
block = data[idx : idx + 16]
|
||
|
|
# Decode next 16-byte block.
|
||
|
|
a0, a1 = struct.unpack_from("<BB", block)
|
||
|
|
|
||
|
|
bits = struct.unpack_from("<6B", block, 2)
|
||
|
|
alphacode1 = bits[2] | (bits[3] << 8) | (bits[4] << 16) | (bits[5] << 24)
|
||
|
|
alphacode2 = bits[0] | (bits[1] << 8)
|
||
|
|
|
||
|
|
color0, color1 = struct.unpack_from("<HH", block, 8)
|
||
|
|
|
||
|
|
(code,) = struct.unpack_from("<I", block, 12)
|
||
|
|
|
||
|
|
r0, g0, b0 = unpack_565(color0)
|
||
|
|
r1, g1, b1 = unpack_565(color1)
|
||
|
|
|
||
|
|
for j in range(4):
|
||
|
|
for i in range(4):
|
||
|
|
# get next control op and generate a pixel
|
||
|
|
alphacode_index = 3 * (4 * j + i)
|
||
|
|
|
||
|
|
if alphacode_index <= 12:
|
||
|
|
alphacode = (alphacode2 >> alphacode_index) & 0x07
|
||
|
|
elif alphacode_index == 15:
|
||
|
|
alphacode = (alphacode2 >> 15) | ((alphacode1 << 1) & 0x06)
|
||
|
|
else: # alphacode_index >= 18 and alphacode_index <= 45
|
||
|
|
alphacode = (alphacode1 >> (alphacode_index - 16)) & 0x07
|
||
|
|
|
||
|
|
if alphacode == 0:
|
||
|
|
a = a0
|
||
|
|
elif alphacode == 1:
|
||
|
|
a = a1
|
||
|
|
elif a0 > a1:
|
||
|
|
a = ((8 - alphacode) * a0 + (alphacode - 1) * a1) // 7
|
||
|
|
elif alphacode == 6:
|
||
|
|
a = 0
|
||
|
|
elif alphacode == 7:
|
||
|
|
a = 255
|
||
|
|
else:
|
||
|
|
a = ((6 - alphacode) * a0 + (alphacode - 1) * a1) // 5
|
||
|
|
|
||
|
|
color_code = (code >> 2 * (4 * j + i)) & 0x03
|
||
|
|
|
||
|
|
if color_code == 0:
|
||
|
|
r, g, b = r0, g0, b0
|
||
|
|
elif color_code == 1:
|
||
|
|
r, g, b = r1, g1, b1
|
||
|
|
elif color_code == 2:
|
||
|
|
r = (2 * r0 + r1) // 3
|
||
|
|
g = (2 * g0 + g1) // 3
|
||
|
|
b = (2 * b0 + b1) // 3
|
||
|
|
elif color_code == 3:
|
||
|
|
r = (2 * r1 + r0) // 3
|
||
|
|
g = (2 * g1 + g0) // 3
|
||
|
|
b = (2 * b1 + b0) // 3
|
||
|
|
|
||
|
|
ret[j].extend([r, g, b, a])
|
||
|
|
|
||
|
|
return ret
|
||
|
|
|
||
|
|
|
||
|
|
class BLPFormatError(NotImplementedError):
|
||
|
|
pass
|
||
|
|
|
||
|
|
|
||
|
|
def _accept(prefix):
|
||
|
|
return prefix[:4] in (b"BLP1", b"BLP2")
|
||
|
|
|
||
|
|
|
||
|
|
class BlpImageFile(ImageFile.ImageFile):
|
||
|
|
"""
|
||
|
|
Blizzard Mipmap Format
|
||
|
|
"""
|
||
|
|
|
||
|
|
format = "BLP"
|
||
|
|
format_description = "Blizzard Mipmap Format"
|
||
|
|
|
||
|
|
def _open(self):
|
||
|
|
self.magic = self.fp.read(4)
|
||
|
|
|
||
|
|
self.fp.seek(5, os.SEEK_CUR)
|
||
|
|
(self._blp_alpha_depth,) = struct.unpack("<b", self.fp.read(1))
|
||
|
|
|
||
|
|
self.fp.seek(2, os.SEEK_CUR)
|
||
|
|
self._size = struct.unpack("<II", self.fp.read(8))
|
||
|
|
|
||
|
|
if self.magic in (b"BLP1", b"BLP2"):
|
||
|
|
decoder = self.magic.decode()
|
||
|
|
else:
|
||
|
|
msg = f"Bad BLP magic {repr(self.magic)}"
|
||
|
|
raise BLPFormatError(msg)
|
||
|
|
|
||
|
|
self._mode = "RGBA" if self._blp_alpha_depth else "RGB"
|
||
|
|
self.tile = [(decoder, (0, 0) + self.size, 0, (self.mode, 0, 1))]
|
||
|
|
|
||
|
|
|
||
|
|
class _BLPBaseDecoder(ImageFile.PyDecoder):
|
||
|
|
_pulls_fd = True
|
||
|
|
|
||
|
|
def decode(self, buffer):
|
||
|
|
try:
|
||
|
|
self._read_blp_header()
|
||
|
|
self._load()
|
||
|
|
except struct.error as e:
|
||
|
|
msg = "Truncated BLP file"
|
||
|
|
raise OSError(msg) from e
|
||
|
|
return -1, 0
|
||
|
|
|
||
|
|
def _read_blp_header(self):
|
||
|
|
self.fd.seek(4)
|
||
|
|
(self._blp_compression,) = struct.unpack("<i", self._safe_read(4))
|
||
|
|
|
||
|
|
(self._blp_encoding,) = struct.unpack("<b", self._safe_read(1))
|
||
|
|
(self._blp_alpha_depth,) = struct.unpack("<b", self._safe_read(1))
|
||
|
|
(self._blp_alpha_encoding,) = struct.unpack("<b", self._safe_read(1))
|
||
|
|
self.fd.seek(1, os.SEEK_CUR) # mips
|
||
|
|
|
||
|
|
self.size = struct.unpack("<II", self._safe_read(8))
|
||
|
|
|
||
|
|
if isinstance(self, BLP1Decoder):
|
||
|
|
# Only present for BLP1
|
||
|
|
(self._blp_encoding,) = struct.unpack("<i", self._safe_read(4))
|
||
|
|
self.fd.seek(4, os.SEEK_CUR) # subtype
|
||
|
|
|
||
|
|
self._blp_offsets = struct.unpack("<16I", self._safe_read(16 * 4))
|
||
|
|
self._blp_lengths = struct.unpack("<16I", self._safe_read(16 * 4))
|
||
|
|
|
||
|
|
def _safe_read(self, length):
|
||
|
|
return ImageFile._safe_read(self.fd, length)
|
||
|
|
|
||
|
|
def _read_palette(self):
|
||
|
|
ret = []
|
||
|
|
for i in range(256):
|
||
|
|
try:
|
||
|
|
b, g, r, a = struct.unpack("<4B", self._safe_read(4))
|
||
|
|
except struct.error:
|
||
|
|
break
|
||
|
|
ret.append((b, g, r, a))
|
||
|
|
return ret
|
||
|
|
|
||
|
|
def _read_bgra(self, palette):
|
||
|
|
data = bytearray()
|
||
|
|
_data = BytesIO(self._safe_read(self._blp_lengths[0]))
|
||
|
|
while True:
|
||
|
|
try:
|
||
|
|
(offset,) = struct.unpack("<B", _data.read(1))
|
||
|
|
except struct.error:
|
||
|
|
break
|
||
|
|
b, g, r, a = palette[offset]
|
||
|
|
d = (r, g, b)
|
||
|
|
if self._blp_alpha_depth:
|
||
|
|
d += (a,)
|
||
|
|
data.extend(d)
|
||
|
|
return data
|
||
|
|
|
||
|
|
|
||
|
|
class BLP1Decoder(_BLPBaseDecoder):
|
||
|
|
def _load(self):
|
||
|
|
if self._blp_compression == Format.JPEG:
|
||
|
|
self._decode_jpeg_stream()
|
||
|
|
|
||
|
|
elif self._blp_compression == 1:
|
||
|
|
if self._blp_encoding in (4, 5):
|
||
|
|
palette = self._read_palette()
|
||
|
|
data = self._read_bgra(palette)
|
||
|
|
self.set_as_raw(data)
|
||
|
|
else:
|
||
|
|
msg = f"Unsupported BLP encoding {repr(self._blp_encoding)}"
|
||
|
|
raise BLPFormatError(msg)
|
||
|
|
else:
|
||
|
|
msg = f"Unsupported BLP compression {repr(self._blp_encoding)}"
|
||
|
|
raise BLPFormatError(msg)
|
||
|
|
|
||
|
|
def _decode_jpeg_stream(self):
|
||
|
|
from .JpegImagePlugin import JpegImageFile
|
||
|
|
|
||
|
|
(jpeg_header_size,) = struct.unpack("<I", self._safe_read(4))
|
||
|
|
jpeg_header = self._safe_read(jpeg_header_size)
|
||
|
|
self._safe_read(self._blp_offsets[0] - self.fd.tell()) # What IS this?
|
||
|
|
data = self._safe_read(self._blp_lengths[0])
|
||
|
|
data = jpeg_header + data
|
||
|
|
data = BytesIO(data)
|
||
|
|
image = JpegImageFile(data)
|
||
|
|
Image._decompression_bomb_check(image.size)
|
||
|
|
if image.mode == "CMYK":
|
||
|
|
decoder_name, extents, offset, args = image.tile[0]
|
||
|
|
image.tile = [(decoder_name, extents, offset, (args[0], "CMYK"))]
|
||
|
|
r, g, b = image.convert("RGB").split()
|
||
|
|
image = Image.merge("RGB", (b, g, r))
|
||
|
|
self.set_as_raw(image.tobytes())
|
||
|
|
|
||
|
|
|
||
|
|
class BLP2Decoder(_BLPBaseDecoder):
|
||
|
|
def _load(self):
|
||
|
|
palette = self._read_palette()
|
||
|
|
|
||
|
|
self.fd.seek(self._blp_offsets[0])
|
||
|
|
|
||
|
|
if self._blp_compression == 1:
|
||
|
|
# Uncompressed or DirectX compression
|
||
|
|
|
||
|
|
if self._blp_encoding == Encoding.UNCOMPRESSED:
|
||
|
|
data = self._read_bgra(palette)
|
||
|
|
|
||
|
|
elif self._blp_encoding == Encoding.DXT:
|
||
|
|
data = bytearray()
|
||
|
|
if self._blp_alpha_encoding == AlphaEncoding.DXT1:
|
||
|
|
linesize = (self.size[0] + 3) // 4 * 8
|
||
|
|
for yb in range((self.size[1] + 3) // 4):
|
||
|
|
for d in decode_dxt1(
|
||
|
|
self._safe_read(linesize), alpha=bool(self._blp_alpha_depth)
|
||
|
|
):
|
||
|
|
data += d
|
||
|
|
|
||
|
|
elif self._blp_alpha_encoding == AlphaEncoding.DXT3:
|
||
|
|
linesize = (self.size[0] + 3) // 4 * 16
|
||
|
|
for yb in range((self.size[1] + 3) // 4):
|
||
|
|
for d in decode_dxt3(self._safe_read(linesize)):
|
||
|
|
data += d
|
||
|
|
|
||
|
|
elif self._blp_alpha_encoding == AlphaEncoding.DXT5:
|
||
|
|
linesize = (self.size[0] + 3) // 4 * 16
|
||
|
|
for yb in range((self.size[1] + 3) // 4):
|
||
|
|
for d in decode_dxt5(self._safe_read(linesize)):
|
||
|
|
data += d
|
||
|
|
else:
|
||
|
|
msg = f"Unsupported alpha encoding {repr(self._blp_alpha_encoding)}"
|
||
|
|
raise BLPFormatError(msg)
|
||
|
|
else:
|
||
|
|
msg = f"Unknown BLP encoding {repr(self._blp_encoding)}"
|
||
|
|
raise BLPFormatError(msg)
|
||
|
|
|
||
|
|
else:
|
||
|
|
msg = f"Unknown BLP compression {repr(self._blp_compression)}"
|
||
|
|
raise BLPFormatError(msg)
|
||
|
|
|
||
|
|
self.set_as_raw(data)
|
||
|
|
|
||
|
|
|
||
|
|
class BLPEncoder(ImageFile.PyEncoder):
|
||
|
|
_pushes_fd = True
|
||
|
|
|
||
|
|
def _write_palette(self):
|
||
|
|
data = b""
|
||
|
|
palette = self.im.getpalette("RGBA", "RGBA")
|
||
|
|
for i in range(len(palette) // 4):
|
||
|
|
r, g, b, a = palette[i * 4 : (i + 1) * 4]
|
||
|
|
data += struct.pack("<4B", b, g, r, a)
|
||
|
|
while len(data) < 256 * 4:
|
||
|
|
data += b"\x00" * 4
|
||
|
|
return data
|
||
|
|
|
||
|
|
def encode(self, bufsize):
|
||
|
|
palette_data = self._write_palette()
|
||
|
|
|
||
|
|
offset = 20 + 16 * 4 * 2 + len(palette_data)
|
||
|
|
data = struct.pack("<16I", offset, *((0,) * 15))
|
||
|
|
|
||
|
|
w, h = self.im.size
|
||
|
|
data += struct.pack("<16I", w * h, *((0,) * 15))
|
||
|
|
|
||
|
|
data += palette_data
|
||
|
|
|
||
|
|
for y in range(h):
|
||
|
|
for x in range(w):
|
||
|
|
data += struct.pack("<B", self.im.getpixel((x, y)))
|
||
|
|
|
||
|
|
return len(data), 0, data
|
||
|
|
|
||
|
|
|
||
|
|
def _save(im, fp, filename):
|
||
|
|
if im.mode != "P":
|
||
|
|
msg = "Unsupported BLP image mode"
|
||
|
|
raise ValueError(msg)
|
||
|
|
|
||
|
|
magic = b"BLP1" if im.encoderinfo.get("blp_version") == "BLP1" else b"BLP2"
|
||
|
|
fp.write(magic)
|
||
|
|
|
||
|
|
fp.write(struct.pack("<i", 1)) # Uncompressed or DirectX compression
|
||
|
|
fp.write(struct.pack("<b", Encoding.UNCOMPRESSED))
|
||
|
|
fp.write(struct.pack("<b", 1 if im.palette.mode == "RGBA" else 0))
|
||
|
|
fp.write(struct.pack("<b", 0)) # alpha encoding
|
||
|
|
fp.write(struct.pack("<b", 0)) # mips
|
||
|
|
fp.write(struct.pack("<II", *im.size))
|
||
|
|
if magic == b"BLP1":
|
||
|
|
fp.write(struct.pack("<i", 5))
|
||
|
|
fp.write(struct.pack("<i", 0))
|
||
|
|
|
||
|
|
ImageFile._save(im, fp, [("BLP", (0, 0) + im.size, 0, im.mode)])
|
||
|
|
|
||
|
|
|
||
|
|
Image.register_open(BlpImageFile.format, BlpImageFile, _accept)
|
||
|
|
Image.register_extension(BlpImageFile.format, ".blp")
|
||
|
|
Image.register_decoder("BLP1", BLP1Decoder)
|
||
|
|
Image.register_decoder("BLP2", BLP2Decoder)
|
||
|
|
|
||
|
|
Image.register_save(BlpImageFile.format, _save)
|
||
|
|
Image.register_encoder("BLP", BLPEncoder)
|