pixfmt-packed-yuv.rst (8402B)
1.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later 2 3.. _packed-yuv: 4 5****************** 6Packed YUV formats 7****************** 8 9Similarly to the packed RGB formats, the packed YUV formats store the Y, Cb and 10Cr components consecutively in memory. They may apply subsampling to the chroma 11components and thus differ in how they interlave the three components. 12 13.. note:: 14 15 - In all the tables that follow, bit 7 is the most significant bit in a byte. 16 - 'Y', 'Cb' and 'Cr' denote bits of the luma, blue chroma (also known as 17 'U') and red chroma (also known as 'V') components respectively. 'A' 18 denotes bits of the alpha component (if supported by the format), and 'X' 19 denotes padding bits. 20 21 224:4:4 Subsampling 23================= 24 25These formats do not subsample the chroma components and store each pixels as a 26full triplet of Y, Cb and Cr values. 27 28The next table lists the packed YUV 4:4:4 formats with less than 8 bits per 29component. They are named based on the order of the Y, Cb and Cr components as 30seen in a 16-bit word, which is then stored in memory in little endian byte 31order, and on the number of bits for each component. For instance the YUV565 32format stores a pixel in a 16-bit word [15:0] laid out at as [Y'\ :sub:`4-0` 33Cb\ :sub:`5-0` Cr\ :sub:`4-0`], and stored in memory in two bytes, 34[Cb\ :sub:`2-0` Cr\ :sub:`4-0`] followed by [Y'\ :sub:`4-0` Cb\ :sub:`5-3`]. 35 36.. raw:: latex 37 38 \begingroup 39 \scriptsize 40 \setlength{\tabcolsep}{2pt} 41 42.. tabularcolumns:: |p{3.5cm}|p{0.96cm}|p{0.52cm}|p{0.52cm}|p{0.52cm}|p{0.52cm}|p{0.52cm}|p{0.52cm}|p{0.52cm}|p{0.52cm}|p{0.52cm}|p{0.52cm}|p{0.52cm}|p{0.52cm}|p{0.52cm}|p{0.52cm}|p{0.52cm}|p{0.52cm}| 43 44.. flat-table:: Packed YUV 4:4:4 Image Formats (less than 8bpc) 45 :header-rows: 2 46 :stub-columns: 0 47 48 * - Identifier 49 - Code 50 51 - :cspan:`7` Byte 0 in memory 52 53 - :cspan:`7` Byte 1 54 55 * - 56 - 57 - 7 58 - 6 59 - 5 60 - 4 61 - 3 62 - 2 63 - 1 64 - 0 65 66 - 7 67 - 6 68 - 5 69 - 4 70 - 3 71 - 2 72 - 1 73 - 0 74 75 * .. _V4L2-PIX-FMT-YUV444: 76 77 - ``V4L2_PIX_FMT_YUV444`` 78 - 'Y444' 79 80 - Cb\ :sub:`3` 81 - Cb\ :sub:`2` 82 - Cb\ :sub:`1` 83 - Cb\ :sub:`0` 84 - Cr\ :sub:`3` 85 - Cr\ :sub:`2` 86 - Cr\ :sub:`1` 87 - Cr\ :sub:`0` 88 89 - a\ :sub:`3` 90 - a\ :sub:`2` 91 - a\ :sub:`1` 92 - a\ :sub:`0` 93 - Y'\ :sub:`3` 94 - Y'\ :sub:`2` 95 - Y'\ :sub:`1` 96 - Y'\ :sub:`0` 97 98 * .. _V4L2-PIX-FMT-YUV555: 99 100 - ``V4L2_PIX_FMT_YUV555`` 101 - 'YUVO' 102 103 - Cb\ :sub:`2` 104 - Cb\ :sub:`1` 105 - Cb\ :sub:`0` 106 - Cr\ :sub:`4` 107 - Cr\ :sub:`3` 108 - Cr\ :sub:`2` 109 - Cr\ :sub:`1` 110 - Cr\ :sub:`0` 111 112 - a 113 - Y'\ :sub:`4` 114 - Y'\ :sub:`3` 115 - Y'\ :sub:`2` 116 - Y'\ :sub:`1` 117 - Y'\ :sub:`0` 118 - Cb\ :sub:`4` 119 - Cb\ :sub:`3` 120 121 * .. _V4L2-PIX-FMT-YUV565: 122 123 - ``V4L2_PIX_FMT_YUV565`` 124 - 'YUVP' 125 126 - Cb\ :sub:`2` 127 - Cb\ :sub:`1` 128 - Cb\ :sub:`0` 129 - Cr\ :sub:`4` 130 - Cr\ :sub:`3` 131 - Cr\ :sub:`2` 132 - Cr\ :sub:`1` 133 - Cr\ :sub:`0` 134 135 - Y'\ :sub:`4` 136 - Y'\ :sub:`3` 137 - Y'\ :sub:`2` 138 - Y'\ :sub:`1` 139 - Y'\ :sub:`0` 140 - Cb\ :sub:`5` 141 - Cb\ :sub:`4` 142 - Cb\ :sub:`3` 143 144.. raw:: latex 145 146 \endgroup 147 148.. note:: 149 150 For the YUV444 and YUV555 formats, the value of alpha bits is undefined 151 when reading from the driver, ignored when writing to the driver, except 152 when alpha blending has been negotiated for a :ref:`Video Overlay 153 <overlay>` or :ref:`Video Output Overlay <osd>`. 154 155 156The next table lists the packed YUV 4:4:4 formats with 8 bits per component. 157They are named based on the order of the Y, Cb and Cr components as stored in 158memory, and on the total number of bits per pixel. For instance, the VUYX32 159format stores a pixel with Cr\ :sub:`7-0` in the first byte, Cb\ :sub:`7-0` in 160the second byte and Y'\ :sub:`7-0` in the third byte. 161 162.. flat-table:: Packed YUV Image Formats (8bpc) 163 :header-rows: 1 164 :stub-columns: 0 165 166 * - Identifier 167 - Code 168 - Byte 0 169 - Byte 1 170 - Byte 2 171 - Byte 3 172 173 * .. _V4L2-PIX-FMT-YUV32: 174 175 - ``V4L2_PIX_FMT_YUV32`` 176 - 'YUV4' 177 178 - A\ :sub:`7-0` 179 - Y'\ :sub:`7-0` 180 - Cb\ :sub:`7-0` 181 - Cr\ :sub:`7-0` 182 183 * .. _V4L2-PIX-FMT-AYUV32: 184 185 - ``V4L2_PIX_FMT_AYUV32`` 186 - 'AYUV' 187 188 - A\ :sub:`7-0` 189 - Y'\ :sub:`7-0` 190 - Cb\ :sub:`7-0` 191 - Cr\ :sub:`7-0` 192 193 * .. _V4L2-PIX-FMT-XYUV32: 194 195 - ``V4L2_PIX_FMT_XYUV32`` 196 - 'XYUV' 197 198 - X\ :sub:`7-0` 199 - Y'\ :sub:`7-0` 200 - Cb\ :sub:`7-0` 201 - Cr\ :sub:`7-0` 202 203 * .. _V4L2-PIX-FMT-VUYA32: 204 205 - ``V4L2_PIX_FMT_VUYA32`` 206 - 'VUYA' 207 208 - Cr\ :sub:`7-0` 209 - Cb\ :sub:`7-0` 210 - Y'\ :sub:`7-0` 211 - A\ :sub:`7-0` 212 213 * .. _V4L2-PIX-FMT-VUYX32: 214 215 - ``V4L2_PIX_FMT_VUYX32`` 216 - 'VUYX' 217 218 - Cr\ :sub:`7-0` 219 - Cb\ :sub:`7-0` 220 - Y'\ :sub:`7-0` 221 - X\ :sub:`7-0` 222 223 * .. _V4L2-PIX-FMT-YUV24: 224 225 - ``V4L2_PIX_FMT_YUV24`` 226 - 'YUV3' 227 228 - Y'\ :sub:`7-0` 229 - Cb\ :sub:`7-0` 230 - Cr\ :sub:`7-0` 231 - -\ 232 233.. note:: 234 235 - The alpha component is expected to contain a meaningful value that can be 236 used by drivers and applications. 237 - The padding bits contain undefined values that must be ignored by all 238 applications and drivers. 239 240 2414:2:2 Subsampling 242================= 243 244These formats, commonly referred to as YUYV or YUY2, subsample the chroma 245components horizontally by 2, storing 2 pixels in 4 bytes. 246 247.. raw:: latex 248 249 \footnotesize 250 251.. tabularcolumns:: |p{3.4cm}|p{1.2cm}|p{0.8cm}|p{0.8cm}|p{0.8cm}|p{0.8cm}|p{0.8cm}|p{0.8cm}|p{0.8cm}|p{0.8cm}| 252 253.. flat-table:: Packed YUV 4:2:2 Formats 254 :header-rows: 1 255 :stub-columns: 0 256 257 * - Identifier 258 - Code 259 - Byte 0 260 - Byte 1 261 - Byte 2 262 - Byte 3 263 - Byte 4 264 - Byte 5 265 - Byte 6 266 - Byte 7 267 * .. _V4L2-PIX-FMT-UYVY: 268 269 - ``V4L2_PIX_FMT_UYVY`` 270 - 'UYVY' 271 272 - Cb\ :sub:`0` 273 - Y'\ :sub:`0` 274 - Cr\ :sub:`0` 275 - Y'\ :sub:`1` 276 - Cb\ :sub:`2` 277 - Y'\ :sub:`2` 278 - Cr\ :sub:`2` 279 - Y'\ :sub:`3` 280 * .. _V4L2-PIX-FMT-VYUY: 281 282 - ``V4L2_PIX_FMT_VYUY`` 283 - 'VYUY' 284 285 - Cr\ :sub:`0` 286 - Y'\ :sub:`0` 287 - Cb\ :sub:`0` 288 - Y'\ :sub:`1` 289 - Cr\ :sub:`2` 290 - Y'\ :sub:`2` 291 - Cb\ :sub:`2` 292 - Y'\ :sub:`3` 293 * .. _V4L2-PIX-FMT-YUYV: 294 295 - ``V4L2_PIX_FMT_YUYV`` 296 - 'YUYV' 297 298 - Y'\ :sub:`0` 299 - Cb\ :sub:`0` 300 - Y'\ :sub:`1` 301 - Cr\ :sub:`0` 302 - Y'\ :sub:`2` 303 - Cb\ :sub:`2` 304 - Y'\ :sub:`3` 305 - Cr\ :sub:`2` 306 * .. _V4L2-PIX-FMT-YVYU: 307 308 - ``V4L2_PIX_FMT_YVYU`` 309 - 'YVYU' 310 311 - Y'\ :sub:`0` 312 - Cr\ :sub:`0` 313 - Y'\ :sub:`1` 314 - Cb\ :sub:`0` 315 - Y'\ :sub:`2` 316 - Cr\ :sub:`2` 317 - Y'\ :sub:`3` 318 - Cb\ :sub:`2` 319 320.. raw:: latex 321 322 \normalsize 323 324**Color Sample Location:** 325Chroma samples are :ref:`interstitially sited<yuv-chroma-centered>` 326horizontally. 327 328 3294:1:1 Subsampling 330================= 331 332This format subsamples the chroma components horizontally by 4, storing 8 333pixels in 12 bytes. 334 335.. raw:: latex 336 337 \scriptsize 338 339.. tabularcolumns:: |p{2.9cm}|p{0.8cm}|p{0.5cm}|p{0.5cm}|p{0.5cm}|p{0.5cm}|p{0.5cm}|p{0.5cm}|p{0.5cm}|p{0.5cm}|p{0.5cm}|p{0.5cm}|p{0.5cm}|p{0.5cm}| 340 341.. flat-table:: Packed YUV 4:1:1 Formats 342 :header-rows: 1 343 :stub-columns: 0 344 345 * - Identifier 346 - Code 347 - Byte 0 348 - Byte 1 349 - Byte 2 350 - Byte 3 351 - Byte 4 352 - Byte 5 353 - Byte 6 354 - Byte 7 355 - Byte 8 356 - Byte 9 357 - Byte 10 358 - Byte 11 359 * .. _V4L2-PIX-FMT-Y41P: 360 361 - ``V4L2_PIX_FMT_Y41P`` 362 - 'Y41P' 363 364 - Cb\ :sub:`0` 365 - Y'\ :sub:`0` 366 - Cr\ :sub:`0` 367 - Y'\ :sub:`1` 368 - Cb\ :sub:`4` 369 - Y'\ :sub:`2` 370 - Cr\ :sub:`4` 371 - Y'\ :sub:`3` 372 - Y'\ :sub:`4` 373 - Y'\ :sub:`5` 374 - Y'\ :sub:`6` 375 - Y'\ :sub:`7` 376 377.. raw:: latex 378 379 \normalsize 380 381.. note:: 382 383 Do not confuse ``V4L2_PIX_FMT_Y41P`` with 384 :ref:`V4L2_PIX_FMT_YUV411P <V4L2-PIX-FMT-YUV411P>`. Y41P is derived from 385 "YUV 4:1:1 **packed**", while YUV411P stands for "YUV 4:1:1 **planar**". 386 387**Color Sample Location:** 388Chroma samples are :ref:`interstitially sited<yuv-chroma-centered>` 389horizontally.