Added reading non-JPEG BLP1 as RGBA

This commit is contained in:
Andrew Murray 2022-02-25 17:50:21 +11:00
parent 3ec928251c
commit 1859bc3462

View File

@ -288,15 +288,12 @@ class BlpImageFile(ImageFile.ImageFile):
self.fp.seek(2, os.SEEK_CUR)
self._size = struct.unpack("<II", self.fp.read(8))
if self.magic == b"BLP1":
decoder = "BLP1"
self.mode = "RGB"
elif self.magic == b"BLP2":
decoder = "BLP2"
self.mode = "RGBA" if self._blp_alpha_depth else "RGB"
if self.magic in (b"BLP1", b"BLP2"):
decoder = self.magic.decode()
else:
raise BLPFormatError(f"Bad BLP magic {repr(self.magic)}")
self.mode = "RGBA" if self._blp_alpha_depth else "RGB"
self.tile = [(decoder, (0, 0) + self.size, 0, (self.mode, 0, 1))]
@ -311,19 +308,6 @@ class _BLPBaseDecoder(ImageFile.PyDecoder):
raise OSError("Truncated BLP file") from e
return 0, 0
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_blp_header(self):
self.fd.seek(4)
(self._blp_compression,) = struct.unpack("<i", self._safe_read(4))
@ -343,6 +327,34 @@ class _BLPBaseDecoder(ImageFile.PyDecoder):
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):
@ -351,17 +363,8 @@ class BLP1Decoder(_BLPBaseDecoder):
elif self._blp_compression == 1:
if self._blp_encoding in (4, 5):
data = bytearray()
palette = self._read_palette()
_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]
data.extend([r, g, b])
data = self._read_bgra(palette)
self.set_as_raw(bytes(data))
else:
raise BLPFormatError(
@ -392,26 +395,16 @@ class BLP2Decoder(_BLPBaseDecoder):
def _load(self):
palette = self._read_palette()
data = bytearray()
self.fd.seek(self._blp_offsets[0])
if self._blp_compression == 1:
# Uncompressed or DirectX compression
if self._blp_encoding == Encoding.UNCOMPRESSED:
_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)
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):