Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.11/site-packages/PIL/WebPImagePlugin.py: 40%

1from __future__ import annotations 

2 

3from io import BytesIO 

4 

5from . import Image, ImageFile 

6 

7try: 

8 from . import _webp 

9 

10 SUPPORTED = True 

11except ImportError: 

12 SUPPORTED = False 

13 

14TYPE_CHECKING = False 

15if TYPE_CHECKING: 

16 from typing import IO, Any 

17 

18_VP8_MODES_BY_IDENTIFIER = { 

19 b"VP8 ": "RGB", 

20 b"VP8X": "RGBA", 

21 b"VP8L": "RGBA", # lossless 

22} 

23 

24 

25def _accept(prefix: bytes) -> bool | str: 

26 is_riff_file_format = prefix.startswith(b"RIFF") 

27 is_webp_file = prefix[8:12] == b"WEBP" 

28 is_valid_vp8_mode = prefix[12:16] in _VP8_MODES_BY_IDENTIFIER 

29 

30 if is_riff_file_format and is_webp_file and is_valid_vp8_mode: 

31 if not SUPPORTED: 

32 return ( 

33 "image file could not be identified because WEBP support not installed" 

34 ) 

35 return True 

36 return False 

37 

38 

39class WebPImageFile(ImageFile.ImageFile): 

40 format = "WEBP" 

41 format_description = "WebP image" 

42 __loaded = 0 

43 __logical_frame = 0 

44 

45 def _open(self) -> None: 

46 assert self.fp is not None 

47 s = self.fp.read() 

48 if not _accept(s): 

49 msg = "not a WEBP file" 

50 raise SyntaxError(msg) 

51 

52 # Use the newer AnimDecoder API to parse the (possibly) animated file, 

53 # and access muxed chunks like ICC/EXIF/XMP. 

54 self._decoder = _webp.WebPAnimDecoder(s) 

55 

56 # Get info from decoder 

57 self._size, self.info["loop"], bgcolor, self.n_frames, self.rawmode = ( 

58 self._decoder.get_info() 

59 ) 

60 self.info["background"] = ( 

61 (bgcolor >> 16) & 0xFF, # R 

62 (bgcolor >> 8) & 0xFF, # G 

63 bgcolor & 0xFF, # B 

64 (bgcolor >> 24) & 0xFF, # A 

65 ) 

66 self.is_animated = self.n_frames > 1 

67 self._mode = "RGB" if self.rawmode == "RGBX" else self.rawmode 

68 

69 # Attempt to read ICC / EXIF / XMP chunks from file 

70 for key, chunk_name in { 

71 "icc_profile": "ICCP", 

72 "exif": "EXIF", 

73 "xmp": "XMP ", 

74 }.items(): 

75 if value := self._decoder.get_chunk(chunk_name): 

76 self.info[key] = value 

77 

78 # Initialize seek state 

79 self._reset(reset=False) 

80 

81 def _getexif(self) -> dict[int, Any] | None: 

82 if "exif" not in self.info: 

83 return None 

84 return self.getexif()._get_merged_dict() 

85 

86 def seek(self, frame: int) -> None: 

87 if not self._seek_check(frame): 

88 return 

89 

90 # Set logical frame to requested position 

91 self.__logical_frame = frame 

92 

93 def _reset(self, reset: bool = True) -> None: 

94 if reset: 

95 self._decoder.reset() 

96 self.__physical_frame = 0 

97 self.__loaded = -1 

98 self.__timestamp = 0 

99 

100 def _get_next(self) -> tuple[bytes, int, int]: 

101 # Get next frame 

102 ret = self._decoder.get_next() 

103 self.__physical_frame += 1 

104 

105 # Check if an error occurred 

106 if ret is None: 

107 self._reset() # Reset just to be safe 

108 self.seek(0) 

109 msg = "failed to decode next frame in WebP file" 

110 raise EOFError(msg) 

111 

112 # Compute duration 

113 data, timestamp = ret 

114 duration = timestamp - self.__timestamp 

115 self.__timestamp = timestamp 

116 

117 # libwebp gives frame end, adjust to start of frame 

118 timestamp -= duration 

119 return data, timestamp, duration 

120 

121 def _seek(self, frame: int) -> None: 

122 if self.__physical_frame == frame: 

123 return # Nothing to do 

124 if frame < self.__physical_frame: 

125 self._reset() # Rewind to beginning 

126 while self.__physical_frame < frame: 

127 self._get_next() # Advance to the requested frame 

128 

129 def load(self) -> Image.core.PixelAccess | None: 

130 if self.__loaded != self.__logical_frame: 

131 self._seek(self.__logical_frame) 

132 

133 # We need to load the image data for this frame 

134 data, self.info["timestamp"], self.info["duration"] = self._get_next() 

135 self.__loaded = self.__logical_frame 

136 

137 # Set tile 

138 if self.fp and self._exclusive_fp: 

139 self.fp.close() 

140 self.fp = BytesIO(data) 

141 self.tile = [ImageFile._Tile("raw", (0, 0) + self.size, 0, self.rawmode)] 

142 

143 return super().load() 

144 

145 def load_seek(self, pos: int) -> None: 

146 pass 

147 

148 def tell(self) -> int: 

149 return self.__logical_frame 

150 

151 

152def _convert_frame(im: Image.Image) -> Image.Image: 

153 # Make sure image mode is supported 

154 if im.mode not in ("RGBX", "RGBA", "RGB"): 

155 im = im.convert("RGBA" if im.has_transparency_data else "RGB") 

156 return im 

157 

158 

159def _save_all(im: Image.Image, fp: IO[bytes], filename: str | bytes) -> None: 

160 encoderinfo = im.encoderinfo.copy() 

161 append_images = list(encoderinfo.get("append_images", [])) 

162 

163 # If total frame count is 1, then save using the legacy API, which 

164 # will preserve non-alpha modes 

165 total = 0 

166 for ims in [im] + append_images: 

167 total += getattr(ims, "n_frames", 1) 

168 if total == 1: 

169 _save(im, fp, filename) 

170 return 

171 

172 background: int | tuple[int, ...] = (0, 0, 0, 0) 

173 if "background" in encoderinfo: 

174 background = encoderinfo["background"] 

175 elif "background" in im.info: 

176 background = im.info["background"] 

177 if isinstance(background, int): 

178 # GifImagePlugin stores a global color table index in 

179 # info["background"]. So it must be converted to an RGBA value 

180 palette = im.getpalette() 

181 if palette: 

182 r, g, b = palette[background * 3 : (background + 1) * 3] 

183 background = (r, g, b, 255) 

184 else: 

185 background = (background, background, background, 255) 

186 

187 duration = im.encoderinfo.get("duration", im.info.get("duration", 0)) 

188 loop = im.encoderinfo.get("loop", 0) 

189 minimize_size = im.encoderinfo.get("minimize_size", False) 

190 kmin = im.encoderinfo.get("kmin", None) 

191 kmax = im.encoderinfo.get("kmax", None) 

192 allow_mixed = im.encoderinfo.get("allow_mixed", False) 

193 verbose = False 

194 lossless = im.encoderinfo.get("lossless", False) 

195 quality = im.encoderinfo.get("quality", 80) 

196 alpha_quality = im.encoderinfo.get("alpha_quality", 100) 

197 method = im.encoderinfo.get("method", 0) 

198 icc_profile = im.encoderinfo.get("icc_profile") or "" 

199 exif = im.encoderinfo.get("exif", "") 

200 if isinstance(exif, Image.Exif): 

201 exif = exif.tobytes() 

202 xmp = im.encoderinfo.get("xmp", "") 

203 if allow_mixed: 

204 lossless = False 

205 

206 # Sensible keyframe defaults are from gif2webp.c script 

207 if kmin is None: 

208 kmin = 9 if lossless else 3 

209 if kmax is None: 

210 kmax = 17 if lossless else 5 

211 

212 # Validate background color 

213 if ( 

214 not isinstance(background, (list, tuple)) 

215 or len(background) != 4 

216 or not all(0 <= v < 256 for v in background) 

217 ): 

218 msg = f"Background color is not an RGBA tuple clamped to (0-255): {background}" 

219 raise OSError(msg) 

220 

221 # Convert to packed uint 

222 bg_r, bg_g, bg_b, bg_a = background 

223 background = (bg_a << 24) | (bg_r << 16) | (bg_g << 8) | (bg_b << 0) 

224 

225 # Setup the WebP animation encoder 

226 enc = _webp.WebPAnimEncoder( 

227 im.size, 

228 background, 

229 loop, 

230 minimize_size, 

231 kmin, 

232 kmax, 

233 allow_mixed, 

234 verbose, 

235 ) 

236 

237 # Add each frame 

238 frame_idx = 0 

239 timestamp = 0 

240 cur_idx = im.tell() 

241 try: 

242 for ims in [im] + append_images: 

243 # Get number of frames in this image 

244 nfr = getattr(ims, "n_frames", 1) 

245 

246 for idx in range(nfr): 

247 ims.seek(idx) 

248 

249 frame = _convert_frame(ims) 

250 

251 # Append the frame to the animation encoder 

252 enc.add( 

253 frame.getim(), 

254 round(timestamp), 

255 lossless, 

256 quality, 

257 alpha_quality, 

258 method, 

259 ) 

260 

261 # Update timestamp and frame index 

262 if isinstance(duration, (list, tuple)): 

263 timestamp += duration[frame_idx] 

264 else: 

265 timestamp += duration 

266 frame_idx += 1 

267 

268 finally: 

269 im.seek(cur_idx) 

270 

271 # Force encoder to flush frames 

272 enc.add(None, round(timestamp), lossless, quality, alpha_quality, 0) 

273 

274 # Get the final output from the encoder 

275 data = enc.assemble(icc_profile, exif, xmp) 

276 if data is None: 

277 msg = "cannot write file as WebP (encoder returned None)" 

278 raise OSError(msg) 

279 

280 fp.write(data) 

281 

282 

283def _save(im: Image.Image, fp: IO[bytes], filename: str | bytes) -> None: 

284 lossless = im.encoderinfo.get("lossless", False) 

285 quality = im.encoderinfo.get("quality", 80) 

286 alpha_quality = im.encoderinfo.get("alpha_quality", 100) 

287 icc_profile = im.encoderinfo.get("icc_profile") or "" 

288 exif = im.encoderinfo.get("exif", b"") 

289 if isinstance(exif, Image.Exif): 

290 exif = exif.tobytes() 

291 if exif.startswith(b"Exif\x00\x00"): 

292 exif = exif[6:] 

293 xmp = im.encoderinfo.get("xmp", "") 

294 method = im.encoderinfo.get("method", 4) 

295 exact = 1 if im.encoderinfo.get("exact") else 0 

296 

297 im = _convert_frame(im) 

298 

299 data = _webp.WebPEncode( 

300 im.getim(), 

301 lossless, 

302 float(quality), 

303 float(alpha_quality), 

304 icc_profile, 

305 method, 

306 exact, 

307 exif, 

308 xmp, 

309 ) 

310 if data is None: 

311 msg = "cannot write file as WebP (encoder returned None)" 

312 raise OSError(msg) 

313 

314 fp.write(data) 

315 

316 

317Image.register_open(WebPImageFile.format, WebPImageFile, _accept) 

318if SUPPORTED: 

319 Image.register_save(WebPImageFile.format, _save) 

320 Image.register_save_all(WebPImageFile.format, _save_all) 

321 Image.register_extension(WebPImageFile.format, ".webp") 

322 Image.register_mime(WebPImageFile.format, "image/webp")