"""
A Pillow loader for .dds files (S3TC-compressed aka DXTC)
Jerome Leclanche <jerome@leclan.ch>
Documentation:
https://web.archive.org/web/20170802060935/http://oss.sgi.com/projects/ogl-sample/registry/EXT/texture_compression_s3tc.txt
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/
"""
from __future__ import annotations
import io
import struct
import sys
from enum import IntEnum, IntFlag
from . import Image, ImageFile, ImagePalette
from ._binary import i32le as i32
from ._binary import o8
from ._binary import o32le as o32
# Magic ("DDS ")
DDS_MAGIC = 0x20534444
# DDS flags
[docs]
class DDSD(IntFlag):
CAPS = 0x1
HEIGHT = 0x2
WIDTH = 0x4
PITCH = 0x8
PIXELFORMAT = 0x1000
MIPMAPCOUNT = 0x20000
LINEARSIZE = 0x80000
DEPTH = 0x800000
# DDS caps
[docs]
class DDSCAPS(IntFlag):
COMPLEX = 0x8
TEXTURE = 0x1000
MIPMAP = 0x400000
[docs]
class DDSCAPS2(IntFlag):
CUBEMAP = 0x200
CUBEMAP_POSITIVEX = 0x400
CUBEMAP_NEGATIVEX = 0x800
CUBEMAP_POSITIVEY = 0x1000
CUBEMAP_NEGATIVEY = 0x2000
CUBEMAP_POSITIVEZ = 0x4000
CUBEMAP_NEGATIVEZ = 0x8000
VOLUME = 0x200000
# Pixel Format
[docs]
class DDPF(IntFlag):
ALPHAPIXELS = 0x1
ALPHA = 0x2
FOURCC = 0x4
PALETTEINDEXED8 = 0x20
RGB = 0x40
LUMINANCE = 0x20000
# dxgiformat.h
[docs]
class D3DFMT(IntEnum):
UNKNOWN = 0
R8G8B8 = 20
A8R8G8B8 = 21
X8R8G8B8 = 22
R5G6B5 = 23
X1R5G5B5 = 24
A1R5G5B5 = 25
A4R4G4B4 = 26
R3G3B2 = 27
A8 = 28
A8R3G3B2 = 29
X4R4G4B4 = 30
A2B10G10R10 = 31
A8B8G8R8 = 32
X8B8G8R8 = 33
G16R16 = 34
A2R10G10B10 = 35
A16B16G16R16 = 36
A8P8 = 40
P8 = 41
L8 = 50
A8L8 = 51
A4L4 = 52
V8U8 = 60
L6V5U5 = 61
X8L8V8U8 = 62
Q8W8V8U8 = 63
V16U16 = 64
A2W10V10U10 = 67
D16_LOCKABLE = 70
D32 = 71
D15S1 = 73
D24S8 = 75
D24X8 = 77
D24X4S4 = 79
D16 = 80
D32F_LOCKABLE = 82
D24FS8 = 83
D32_LOCKABLE = 84
S8_LOCKABLE = 85
L16 = 81
VERTEXDATA = 100
INDEX16 = 101
INDEX32 = 102
Q16W16V16U16 = 110
R16F = 111
G16R16F = 112
A16B16G16R16F = 113
R32F = 114
G32R32F = 115
A32B32G32R32F = 116
CxV8U8 = 117
A1 = 118
A2B10G10R10_XR_BIAS = 119
BINARYBUFFER = 199
UYVY = i32(b"UYVY")
R8G8_B8G8 = i32(b"RGBG")
YUY2 = i32(b"YUY2")
G8R8_G8B8 = i32(b"GRGB")
DXT1 = i32(b"DXT1")
DXT2 = i32(b"DXT2")
DXT3 = i32(b"DXT3")
DXT4 = i32(b"DXT4")
DXT5 = i32(b"DXT5")
DX10 = i32(b"DX10")
BC4S = i32(b"BC4S")
BC4U = i32(b"BC4U")
BC5S = i32(b"BC5S")
BC5U = i32(b"BC5U")
ATI1 = i32(b"ATI1")
ATI2 = i32(b"ATI2")
MULTI2_ARGB8 = i32(b"MET1")
# Backward compatibility layer
module = sys.modules[__name__]
for item in DDSD:
assert item.name is not None
setattr(module, "DDSD_" + item.name, item.value)
for item1 in DDSCAPS:
assert item1.name is not None
setattr(module, "DDSCAPS_" + item1.name, item1.value)
for item2 in DDSCAPS2:
assert item2.name is not None
setattr(module, "DDSCAPS2_" + item2.name, item2.value)
for item3 in DDPF:
assert item3.name is not None
setattr(module, "DDPF_" + item3.name, item3.value)
DDS_FOURCC = DDPF.FOURCC
DDS_RGB = DDPF.RGB
DDS_RGBA = DDPF.RGB | DDPF.ALPHAPIXELS
DDS_LUMINANCE = DDPF.LUMINANCE
DDS_LUMINANCEA = DDPF.LUMINANCE | DDPF.ALPHAPIXELS
DDS_ALPHA = DDPF.ALPHA
DDS_PAL8 = DDPF.PALETTEINDEXED8
DDS_HEADER_FLAGS_TEXTURE = DDSD.CAPS | DDSD.HEIGHT | DDSD.WIDTH | DDSD.PIXELFORMAT
DDS_HEADER_FLAGS_MIPMAP = DDSD.MIPMAPCOUNT
DDS_HEADER_FLAGS_VOLUME = DDSD.DEPTH
DDS_HEADER_FLAGS_PITCH = DDSD.PITCH
DDS_HEADER_FLAGS_LINEARSIZE = DDSD.LINEARSIZE
DDS_HEIGHT = DDSD.HEIGHT
DDS_WIDTH = DDSD.WIDTH
DDS_SURFACE_FLAGS_TEXTURE = DDSCAPS.TEXTURE
DDS_SURFACE_FLAGS_MIPMAP = DDSCAPS.COMPLEX | DDSCAPS.MIPMAP
DDS_SURFACE_FLAGS_CUBEMAP = DDSCAPS.COMPLEX
DDS_CUBEMAP_POSITIVEX = DDSCAPS2.CUBEMAP | DDSCAPS2.CUBEMAP_POSITIVEX
DDS_CUBEMAP_NEGATIVEX = DDSCAPS2.CUBEMAP | DDSCAPS2.CUBEMAP_NEGATIVEX
DDS_CUBEMAP_POSITIVEY = DDSCAPS2.CUBEMAP | DDSCAPS2.CUBEMAP_POSITIVEY
DDS_CUBEMAP_NEGATIVEY = DDSCAPS2.CUBEMAP | DDSCAPS2.CUBEMAP_NEGATIVEY
DDS_CUBEMAP_POSITIVEZ = DDSCAPS2.CUBEMAP | DDSCAPS2.CUBEMAP_POSITIVEZ
DDS_CUBEMAP_NEGATIVEZ = DDSCAPS2.CUBEMAP | DDSCAPS2.CUBEMAP_NEGATIVEZ
DXT1_FOURCC = D3DFMT.DXT1
DXT3_FOURCC = D3DFMT.DXT3
DXT5_FOURCC = D3DFMT.DXT5
DXGI_FORMAT_R8G8B8A8_TYPELESS = DXGI_FORMAT.R8G8B8A8_TYPELESS
DXGI_FORMAT_R8G8B8A8_UNORM = DXGI_FORMAT.R8G8B8A8_UNORM
DXGI_FORMAT_R8G8B8A8_UNORM_SRGB = DXGI_FORMAT.R8G8B8A8_UNORM_SRGB
DXGI_FORMAT_BC5_TYPELESS = DXGI_FORMAT.BC5_TYPELESS
DXGI_FORMAT_BC5_UNORM = DXGI_FORMAT.BC5_UNORM
DXGI_FORMAT_BC5_SNORM = DXGI_FORMAT.BC5_SNORM
DXGI_FORMAT_BC6H_UF16 = DXGI_FORMAT.BC6H_UF16
DXGI_FORMAT_BC6H_SF16 = DXGI_FORMAT.BC6H_SF16
DXGI_FORMAT_BC7_TYPELESS = DXGI_FORMAT.BC7_TYPELESS
DXGI_FORMAT_BC7_UNORM = DXGI_FORMAT.BC7_UNORM
DXGI_FORMAT_BC7_UNORM_SRGB = DXGI_FORMAT.BC7_UNORM_SRGB
[docs]
class DdsImageFile(ImageFile.ImageFile):
format = "DDS"
format_description = "DirectDraw Surface"
def _open(self):
if not _accept(self.fp.read(4)):
msg = "not a DDS file"
raise SyntaxError(msg)
(header_size,) = struct.unpack("<I", self.fp.read(4))
if header_size != 124:
msg = f"Unsupported header size {repr(header_size)}"
raise OSError(msg)
header_bytes = self.fp.read(header_size - 4)
if len(header_bytes) != 120:
msg = f"Incomplete header: {len(header_bytes)} bytes"
raise OSError(msg)
header = io.BytesIO(header_bytes)
flags, height, width = struct.unpack("<3I", header.read(12))
self._size = (width, height)
extents = (0, 0) + self.size
pitch, depth, mipmaps = struct.unpack("<3I", header.read(12))
struct.unpack("<11I", header.read(44)) # reserved
# pixel format
pfsize, pfflags, fourcc, bitcount = struct.unpack("<4I", header.read(16))
n = 0
rawmode = None
if pfflags & DDPF.RGB:
# Texture contains uncompressed RGB data
if pfflags & DDPF.ALPHAPIXELS:
self._mode = "RGBA"
mask_count = 4
else:
self._mode = "RGB"
mask_count = 3
masks = struct.unpack(f"<{mask_count}I", header.read(mask_count * 4))
self.tile = [("dds_rgb", extents, 0, (bitcount, masks))]
return
elif pfflags & DDPF.LUMINANCE:
if bitcount == 8:
self._mode = "L"
elif bitcount == 16 and pfflags & DDPF.ALPHAPIXELS:
self._mode = "LA"
else:
msg = f"Unsupported bitcount {bitcount} for {pfflags}"
raise OSError(msg)
elif pfflags & DDPF.PALETTEINDEXED8:
self._mode = "P"
self.palette = ImagePalette.raw("RGBA", self.fp.read(1024))
elif pfflags & DDPF.FOURCC:
offset = header_size + 4
if fourcc == D3DFMT.DXT1:
self._mode = "RGBA"
self.pixel_format = "DXT1"
n = 1
elif fourcc == D3DFMT.DXT3:
self._mode = "RGBA"
self.pixel_format = "DXT3"
n = 2
elif fourcc == D3DFMT.DXT5:
self._mode = "RGBA"
self.pixel_format = "DXT5"
n = 3
elif fourcc in (D3DFMT.BC4U, D3DFMT.ATI1):
self._mode = "L"
self.pixel_format = "BC4"
n = 4
elif fourcc == D3DFMT.BC5S:
self._mode = "RGB"
self.pixel_format = "BC5S"
n = 5
elif fourcc in (D3DFMT.BC5U, D3DFMT.ATI2):
self._mode = "RGB"
self.pixel_format = "BC5"
n = 5
elif fourcc == D3DFMT.DX10:
offset += 20
# ignoring flags which pertain to volume textures and cubemaps
(dxgi_format,) = struct.unpack("<I", self.fp.read(4))
self.fp.read(16)
if dxgi_format in (
DXGI_FORMAT.BC1_UNORM,
DXGI_FORMAT.BC1_TYPELESS,
):
self._mode = "RGBA"
self.pixel_format = "BC1"
n = 1
elif dxgi_format in (DXGI_FORMAT.BC4_TYPELESS, DXGI_FORMAT.BC4_UNORM):
self._mode = "L"
self.pixel_format = "BC4"
n = 4
elif dxgi_format in (DXGI_FORMAT.BC5_TYPELESS, DXGI_FORMAT.BC5_UNORM):
self._mode = "RGB"
self.pixel_format = "BC5"
n = 5
elif dxgi_format == DXGI_FORMAT.BC5_SNORM:
self._mode = "RGB"
self.pixel_format = "BC5S"
n = 5
elif dxgi_format == DXGI_FORMAT.BC6H_UF16:
self._mode = "RGB"
self.pixel_format = "BC6H"
n = 6
elif dxgi_format == DXGI_FORMAT.BC6H_SF16:
self._mode = "RGB"
self.pixel_format = "BC6HS"
n = 6
elif dxgi_format in (
DXGI_FORMAT.BC7_TYPELESS,
DXGI_FORMAT.BC7_UNORM,
DXGI_FORMAT.BC7_UNORM_SRGB,
):
self._mode = "RGBA"
self.pixel_format = "BC7"
n = 7
if dxgi_format == DXGI_FORMAT.BC7_UNORM_SRGB:
self.info["gamma"] = 1 / 2.2
elif dxgi_format in (
DXGI_FORMAT.R8G8B8A8_TYPELESS,
DXGI_FORMAT.R8G8B8A8_UNORM,
DXGI_FORMAT.R8G8B8A8_UNORM_SRGB,
):
self._mode = "RGBA"
if dxgi_format == DXGI_FORMAT.R8G8B8A8_UNORM_SRGB:
self.info["gamma"] = 1 / 2.2
else:
msg = f"Unimplemented DXGI format {dxgi_format}"
raise NotImplementedError(msg)
else:
msg = f"Unimplemented pixel format {repr(fourcc)}"
raise NotImplementedError(msg)
else:
msg = f"Unknown pixel format flags {pfflags}"
raise NotImplementedError(msg)
if n:
self.tile = [
ImageFile._Tile("bcn", extents, offset, (n, self.pixel_format))
]
else:
self.tile = [ImageFile._Tile("raw", extents, 0, rawmode or self.mode)]
[docs]
def load_seek(self, pos):
pass
[docs]
class DdsRgbDecoder(ImageFile.PyDecoder):
_pulls_fd = True
[docs]
def decode(self, buffer):
bitcount, masks = self.args
# Some masks will be padded with zeros, e.g. R 0b11 G 0b1100
# Calculate how many zeros each mask is padded with
mask_offsets = []
# And the maximum value of each channel without the padding
mask_totals = []
for mask in masks:
offset = 0
if mask != 0:
while mask >> (offset + 1) << (offset + 1) == mask:
offset += 1
mask_offsets.append(offset)
mask_totals.append(mask >> offset)
data = bytearray()
bytecount = bitcount // 8
dest_length = self.state.xsize * self.state.ysize * len(masks)
while len(data) < dest_length:
value = int.from_bytes(self.fd.read(bytecount), "little")
for i, mask in enumerate(masks):
masked_value = value & mask
# Remove the zero padding, and scale it to 8 bits
data += o8(
int(((masked_value >> mask_offsets[i]) / mask_totals[i]) * 255)
)
self.set_as_raw(data)
return -1, 0
def _save(im, fp, filename):
if im.mode not in ("RGB", "RGBA", "L", "LA"):
msg = f"cannot write mode {im.mode} as DDS"
raise OSError(msg)
alpha = im.mode[-1] == "A"
if im.mode[0] == "L":
pixel_flags = DDPF.LUMINANCE
rawmode = im.mode
if alpha:
rgba_mask = [0x000000FF, 0x000000FF, 0x000000FF]
else:
rgba_mask = [0xFF000000, 0xFF000000, 0xFF000000]
else:
pixel_flags = DDPF.RGB
rawmode = im.mode[::-1]
rgba_mask = [0x00FF0000, 0x0000FF00, 0x000000FF]
if alpha:
r, g, b, a = im.split()
im = Image.merge("RGBA", (a, r, g, b))
if alpha:
pixel_flags |= DDPF.ALPHAPIXELS
rgba_mask.append(0xFF000000 if alpha else 0)
flags = DDSD.CAPS | DDSD.HEIGHT | DDSD.WIDTH | DDSD.PITCH | DDSD.PIXELFORMAT
bitcount = len(im.getbands()) * 8
pitch = (im.width * bitcount + 7) // 8
fp.write(
o32(DDS_MAGIC)
+ struct.pack(
"<7I",
124, # header size
flags, # flags
im.height,
im.width,
pitch,
0, # depth
0, # mipmaps
)
+ struct.pack("11I", *((0,) * 11)) # reserved
# pfsize, pfflags, fourcc, bitcount
+ struct.pack("<4I", 32, pixel_flags, 0, bitcount)
+ struct.pack("<4I", *rgba_mask) # dwRGBABitMask
+ struct.pack("<5I", DDSCAPS.TEXTURE, 0, 0, 0, 0)
)
ImageFile._save(
im, fp, [ImageFile._Tile("raw", (0, 0) + im.size, 0, (rawmode, 0, 1))]
)
def _accept(prefix):
return prefix[:4] == b"DDS "
Image.register_open(DdsImageFile.format, DdsImageFile, _accept)
Image.register_decoder("dds_rgb", DdsRgbDecoder)
Image.register_save(DdsImageFile.format, _save)
Image.register_extension(DdsImageFile.format, ".dds")