Lines Matching +full:non +full:- +full:inverted
1 .. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
13 VIDIOC_G_FBUF - VIDIOC_S_FBUF - Get or set frame buffer overlay parameters
46 The V4L2 API distinguishes destructive and non-destructive overlays. A
48 of a graphics card. A non-destructive overlay blends video images into a
50 always non-destructive.
66 To set the parameters for a *non-destructive Video Overlay*,
84 .. flat-table:: struct v4l2_framebuffer
85 :header-rows: 0
86 :stub-columns: 0
89 * - __u32
90 - ``capability``
91 -
92 - Overlay capability flags set by the driver, see
93 :ref:`framebuffer-cap`.
94 * - __u32
95 - ``flags``
96 -
97 - Overlay control flags set by application and driver, see
98 :ref:`framebuffer-flags`
99 * - void *
100 - ``base``
101 -
102 - Physical base address of the framebuffer, that is the address of
104 * -
105 -
106 -
107 - This field is irrelevant to *non-destructive Video Overlays*. For
114 * - struct
115 - ``fmt``
116 -
117 - Layout of the frame buffer.
118 * -
119 - __u32
120 - ``width``
121 - Width of the frame buffer in pixels.
122 * -
123 - __u32
124 - ``height``
125 - Height of the frame buffer in pixels.
126 * -
127 - __u32
128 - ``pixelformat``
129 - The pixel format of the framebuffer.
130 * -
131 -
132 -
133 - For *non-destructive Video Overlays* this field only defines a
136 * -
137 -
138 -
139 - For *destructive Video Overlays* applications must initialize this
142 * -
143 -
144 -
145 - Usually this is an RGB format (for example
146 :ref:`V4L2_PIX_FMT_RGB565 <V4L2-PIX-FMT-RGB565>`) but YUV
152 * -
153 - enum :c:type:`v4l2_field`
154 - ``field``
155 - Drivers and applications shall ignore this field. If applicable,
159 * -
160 - __u32
161 - ``bytesperline``
162 - Distance in bytes between the leftmost pixels in two adjacent
164 * - :cspan:`3`
166 This field is irrelevant to *non-destructive Video Overlays*.
171 ``width`` times bytes-per-pixel or a larger value required by the
190 * -
191 - __u32
192 - ``sizeimage``
193 - This field is irrelevant to *non-destructive Video Overlays*. For
200 * -
201 - enum :c:type:`v4l2_colorspace`
202 - ``colorspace``
203 - This information supplements the ``pixelformat`` and must be set
205 * -
206 - __u32
207 - ``priv``
208 - Reserved. Drivers and applications must set this field to zero.
212 .. _framebuffer-cap:
214 .. flat-table:: Frame Buffer Capability Flags
215 :header-rows: 0
216 :stub-columns: 0
219 * - ``V4L2_FBUF_CAP_EXTERNOVERLAY``
220 - 0x0001
221 - The device is capable of non-destructive overlays. When the driver
224 non-destructive overlays. Video Output Overlays are in practice
225 always non-destructive.
226 * - ``V4L2_FBUF_CAP_CHROMAKEY``
227 - 0x0002
228 - The device supports clipping by chroma-keying the images. That is,
230 the latter assume a certain color. Chroma-keying makes no sense
232 * - ``V4L2_FBUF_CAP_LIST_CLIPPING``
233 - 0x0004
234 - The device supports clipping using a list of clip rectangles.
235 * - ``V4L2_FBUF_CAP_BITMAP_CLIPPING``
236 - 0x0008
237 - The device supports clipping using a bit mask.
238 * - ``V4L2_FBUF_CAP_LOCAL_ALPHA``
239 - 0x0010
240 - The device supports clipping/blending using the alpha channel of
243 * - ``V4L2_FBUF_CAP_GLOBAL_ALPHA``
244 - 0x0020
245 - The device supports alpha blending using a global alpha value.
247 * - ``V4L2_FBUF_CAP_LOCAL_INV_ALPHA``
248 - 0x0040
249 - The device supports clipping/blending using the inverted alpha
252 * - ``V4L2_FBUF_CAP_SRC_CHROMAKEY``
253 - 0x0080
254 - The device supports Source Chroma-keying. Video pixels with the
255 chroma-key colors are replaced by framebuffer pixels, which is
260 .. _framebuffer-flags:
264 .. flat-table:: Frame Buffer Flags
265 :header-rows: 0
266 :stub-columns: 0
269 * - ``V4L2_FBUF_FLAG_PRIMARY``
270 - 0x0001
271 - The framebuffer is the primary graphics surface. In other words,
275 * - ``V4L2_FBUF_FLAG_OVERLAY``
276 - 0x0002
277 - If this flag is set for a video capture device, then the driver
287 relative to the top-left corner of the framebuffer and restricted
290 * - ``V4L2_FBUF_FLAG_CHROMAKEY``
291 - 0x0004
292 - Use chroma-keying. The chroma-key color is determined by the
296 * - :cspan:`2` There are no flags to enable clipping using a list of
300 * - ``V4L2_FBUF_FLAG_LOCAL_ALPHA``
301 - 0x0008
302 - Use the alpha channel of the framebuffer to clip or blend
304 output = framebuffer pixel * alpha + video pixel * (1 - alpha).
306 * - ``V4L2_FBUF_FLAG_GLOBAL_ALPHA``
307 - 0x0010
308 - Use a global alpha value to blend the framebuffer with video
310 + video pixel * (255 - alpha)) / 255. The alpha value is
315 * - ``V4L2_FBUF_FLAG_LOCAL_INV_ALPHA``
316 - 0x0020
317 - Like ``V4L2_FBUF_FLAG_LOCAL_ALPHA``, use the alpha channel of the
319 but with an inverted alpha value. The blend function is: output =
320 framebuffer pixel * (1 - alpha) + video pixel * alpha. The actual
322 * - ``V4L2_FBUF_FLAG_SRC_CHROMAKEY``
323 - 0x0040
324 - Use source chroma-keying. The source chroma-key color is
328 and :ref:`osd`. Both chroma-keying are mutual exclusive to each
335 On success 0 is returned, on error -1 and the ``errno`` variable is set
337 :ref:`Generic Error Codes <gen-errors>` chapter.
350 linux-media mailing list: