← Back
Editing: DdsImagePlugin.py
""" 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/ """ import struct from io import BytesIO from . import Image, ImageFile from ._binary import o32le as o32 # Magic ("DDS ") DDS_MAGIC = 0x20534444 # DDS flags DDSD_CAPS = 0x1 DDSD_HEIGHT = 0x2 DDSD_WIDTH = 0x4 DDSD_PITCH = 0x8 DDSD_PIXELFORMAT = 0x1000 DDSD_MIPMAPCOUNT = 0x20000 DDSD_LINEARSIZE = 0x80000 DDSD_DEPTH = 0x800000 # DDS caps DDSCAPS_COMPLEX = 0x8 DDSCAPS_TEXTURE = 0x1000 DDSCAPS_MIPMAP = 0x400000 DDSCAPS2_CUBEMAP = 0x200 DDSCAPS2_CUBEMAP_POSITIVEX = 0x400 DDSCAPS2_CUBEMAP_NEGATIVEX = 0x800 DDSCAPS2_CUBEMAP_POSITIVEY = 0x1000 DDSCAPS2_CUBEMAP_NEGATIVEY = 0x2000 DDSCAPS2_CUBEMAP_POSITIVEZ = 0x4000 DDSCAPS2_CUBEMAP_NEGATIVEZ = 0x8000 DDSCAPS2_VOLUME = 0x200000 # Pixel Format DDPF_ALPHAPIXELS = 0x1 DDPF_ALPHA = 0x2 DDPF_FOURCC = 0x4 DDPF_PALETTEINDEXED8 = 0x20 DDPF_RGB = 0x40 DDPF_LUMINANCE = 0x20000 # dds.h 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 DXT1_FOURCC = 0x31545844 # DXT3 DXT3_FOURCC = 0x33545844 # DXT5 DXT5_FOURCC = 0x35545844 # dxgiformat.h DXGI_FORMAT_R8G8B8A8_TYPELESS = 27 DXGI_FORMAT_R8G8B8A8_UNORM = 28 DXGI_FORMAT_R8G8B8A8_UNORM_SRGB = 29 DXGI_FORMAT_BC5_TYPELESS = 82 DXGI_FORMAT_BC5_UNORM = 83 DXGI_FORMAT_BC5_SNORM = 84 DXGI_FORMAT_BC6H_UF16 = 95 DXGI_FORMAT_BC6H_SF16 = 96 DXGI_FORMAT_BC7_TYPELESS = 97 DXGI_FORMAT_BC7_UNORM = 98 DXGI_FORMAT_BC7_UNORM_SRGB = 99 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 = BytesIO(header_bytes) flags, height, width = struct.unpack("<3I", header.read(12)) self._size = (width, height) self.mode = "RGBA" pitch, depth, mipmaps = struct.unpack("<3I", header.read(12)) struct.unpack("<11I", header.read(44)) # reserved # pixel format pfsize, pfflags = struct.unpack("<2I", header.read(8)) fourcc = header.read(4) (bitcount,) = struct.unpack("<I", header.read(4)) masks = struct.unpack("<4I", header.read(16)) if pfflags & DDPF_LUMINANCE: # Texture contains uncompressed L or LA data if pfflags & DDPF_ALPHAPIXELS: self.mode = "LA" else: self.mode = "L" self.tile = [("raw", (0, 0) + self.size, 0, (self.mode, 0, 1))] elif pfflags & DDPF_RGB: # Texture contains uncompressed RGB data masks = {mask: ["R", "G", "B", "A"][i] for i, mask in enumerate(masks)} rawmode = "" if pfflags & DDPF_ALPHAPIXELS: rawmode += masks[0xFF000000] else: self.mode = "RGB" rawmode += masks[0xFF0000] + masks[0xFF00] + masks[0xFF] self.tile = [("raw", (0, 0) + self.size, 0, (rawmode[::-1], 0, 1))] else: data_start = header_size + 4 n = 0 if fourcc == b"DXT1": self.pixel_format = "DXT1" n = 1 elif fourcc == b"DXT3": self.pixel_format = "DXT3" n = 2 elif fourcc == b"DXT5": self.pixel_format = "DXT5" n = 3 elif fourcc == b"ATI1": self.pixel_format = "BC4" n = 4 self.mode = "L" elif fourcc == b"ATI2": self.pixel_format = "BC5" n = 5 self.mode = "RGB" elif fourcc == b"BC5S": self.pixel_format = "BC5S" n = 5 self.mode = "RGB" elif fourcc == b"DX10": data_start += 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_BC5_TYPELESS, DXGI_FORMAT_BC5_UNORM): self.pixel_format = "BC5" n = 5 self.mode = "RGB" elif dxgi_format == DXGI_FORMAT_BC5_SNORM: self.pixel_format = "BC5S" n = 5 self.mode = "RGB" elif dxgi_format == DXGI_FORMAT_BC6H_UF16: self.pixel_format = "BC6H" n = 6 self.mode = "RGB" elif dxgi_format == DXGI_FORMAT_BC6H_SF16: self.pixel_format = "BC6HS" n = 6 self.mode = "RGB" elif dxgi_format in (DXGI_FORMAT_BC7_TYPELESS, DXGI_FORMAT_BC7_UNORM): self.pixel_format = "BC7" n = 7 elif dxgi_format == DXGI_FORMAT_BC7_UNORM_SRGB: self.pixel_format = "BC7" self.info["gamma"] = 1 / 2.2 n = 7 elif dxgi_format in ( DXGI_FORMAT_R8G8B8A8_TYPELESS, DXGI_FORMAT_R8G8B8A8_UNORM, DXGI_FORMAT_R8G8B8A8_UNORM_SRGB, ): self.tile = [("raw", (0, 0) + self.size, 0, ("RGBA", 0, 1))] if dxgi_format == DXGI_FORMAT_R8G8B8A8_UNORM_SRGB: self.info["gamma"] = 1 / 2.2 return else: msg = f"Unimplemented DXGI format {dxgi_format}" raise NotImplementedError(msg) else: msg = f"Unimplemented pixel format {repr(fourcc)}" raise NotImplementedError(msg) self.tile = [ ("bcn", (0, 0) + self.size, data_start, (n, self.pixel_format)) ] def load_seek(self, pos): pass 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) rawmode = im.mode masks = [0xFF0000, 0xFF00, 0xFF] if im.mode in ("L", "LA"): pixel_flags = DDPF_LUMINANCE else: pixel_flags = DDPF_RGB rawmode = rawmode[::-1] if im.mode in ("LA", "RGBA"): pixel_flags |= DDPF_ALPHAPIXELS masks.append(0xFF000000) bitcount = len(masks) * 8 while len(masks) < 4: masks.append(0) fp.write( o32(DDS_MAGIC) + o32(124) # header size + o32( DDSD_CAPS | DDSD_HEIGHT | DDSD_WIDTH | DDSD_PITCH | DDSD_PIXELFORMAT ) # flags + o32(im.height) + o32(im.width) + o32((im.width * bitcount + 7) // 8) # pitch + o32(0) # depth + o32(0) # mipmaps + o32(0) * 11 # reserved + o32(32) # pfsize + o32(pixel_flags) # pfflags + o32(0) # fourcc + o32(bitcount) # bitcount + b"".join(o32(mask) for mask in masks) # rgbabitmask + o32(DDSCAPS_TEXTURE) # dwCaps + o32(0) # dwCaps2 + o32(0) # dwCaps3 + o32(0) # dwCaps4 + o32(0) # dwReserved2 ) if im.mode == "RGBA": r, g, b, a = im.split() im = Image.merge("RGBA", (a, r, g, b)) ImageFile._save(im, fp, [("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_save(DdsImageFile.format, _save) Image.register_extension(DdsImageFile.format, ".dds")
Save File
Cancel