1 .. Permission is granted to copy, distribute and/or modify this
2 .. document under the terms of the GNU Free Documentation License,
3 .. Version 1.1 or any later version published by the Free Software
4 .. Foundation, with no Invariant Sections, no Front-Cover Texts
5 .. and no Back-Cover Texts. A copy of the license is included at
6 .. Documentation/userspace-api/media/fdl-appendix.rst.
8 .. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
10 .. _v4l2-meta-fmt-d4xx:
12 *******************************
13 V4L2_META_FMT_D4XX ('D4XX')
14 *******************************
16 Intel D4xx UVC Cameras Metadata
22 Intel D4xx (D435 and other) cameras include per-frame metadata in their UVC
23 payload headers, following the Microsoft(R) UVC extension proposal [1_]. That
24 means, that the private D4XX metadata, following the standard UVC header, is
25 organised in blocks. D4XX cameras implement several standard block types,
26 proposed by Microsoft, and several proprietary ones. Supported standard metadata
27 types are MetadataId_CaptureStats (ID 3), MetadataId_CameraExtrinsics (ID 4),
28 and MetadataId_CameraIntrinsics (ID 5). For their description see [1_]. This
29 document describes proprietary metadata types, used by D4xx cameras.
31 V4L2_META_FMT_D4XX buffers follow the metadata buffer layout of
32 V4L2_META_FMT_UVC with the only difference, that it also includes proprietary
33 payload header data. D4xx cameras use bulk transfers and only send one payload
34 per frame, therefore their headers cannot be larger than 255 bytes.
36 Below are proprietary Microsoft style metadata types, used by D4xx cameras,
37 where all fields are in little endian order:
39 .. tabularcolumns:: |p{5.0cm}|p{12.5cm}|
42 .. flat-table:: D4xx metadata
49 * - :cspan:`1` *Depth Control*
53 - Size in bytes (currently 56)
55 - Version of this structure. The documentation herein corresponds to
56 version xxx. The version number will be incremented when new fields are
59 - A bitmask of flags: see [2_] below
61 - Gain value in internal units, same as the V4L2_CID_GAIN control, used to
64 - Exposure time (in microseconds) used to capture the frame
66 - Power of the laser LED 0-360, used for depth measurement
68 - 0: manual; 1: automatic exposure
69 * - __u32 Exposure priority
70 - Exposure priority value: 0 - constant frame rate
72 - Left border of the AE Region of Interest (all ROI values are in pixels
73 and lie between 0 and maximum width or height respectively)
74 * - __u32 AE ROI right
75 - Right border of the AE Region of Interest
77 - Top border of the AE Region of Interest
78 * - __u32 AE ROI bottom
79 - Bottom border of the AE Region of Interest
81 - Preset selector value, default: 0, unless changed by the user
84 * - :cspan:`1` *Capture Timing*
88 - Size in bytes (currently 40)
90 - Version of this structure. The documentation herein corresponds to
91 version xxx. The version number will be incremented when new fields are
94 - A bitmask of flags: see [3_] below
95 * - __u32 Frame counter
96 - Monotonically increasing counter
97 * - __u32 Optical time
98 - Time in microseconds from the beginning of a frame till its middle
99 * - __u32 Readout time
100 - Time, used to read out a frame in microseconds
101 * - __u32 Exposure time
102 - Frame exposure time in microseconds
103 * - __u32 Frame interval
104 - In microseconds = 1000000 / framerate
105 * - __u32 Pipe latency
106 - Time in microseconds from start of frame to data in USB buffer
107 * - :cspan:`1` *Configuration*
111 - Size in bytes (currently 40)
113 - Version of this structure. The documentation herein corresponds to
114 version xxx. The version number will be incremented when new fields are
117 - A bitmask of flags: see [4_] below
118 * - __u8 Hardware type
119 - Camera hardware version [5_]
121 - Camera hardware configuration [6_]
123 - Internal synchronisation
125 - Image format code [7_]
131 - Requested frame rate per second
133 - Byte 0: bit 0: depth and RGB are synchronised, bit 1: external trigger
137 [1] https://docs.microsoft.com/en-us/windows-hardware/drivers/stream/uvc-extensions-1-5
141 [2] Depth Control flags specify which fields are valid: ::
145 0x00000004 Laser power
147 0x00000010 Exposure priority
153 [3] Capture Timing flags specify which fields are valid: ::
155 0x00000001 Frame counter
156 0x00000002 Optical time
157 0x00000004 Readout time
158 0x00000008 Exposure time
159 0x00000010 Frame interval
160 0x00000020 Pipe latency
164 [4] Configuration flags specify which fields are valid: ::
166 0x00000001 Hardware type
185 [6] 8-bit camera hardware configuration bitfield: ::
192 [2] depthIsActive - has a laser projector
194 [4] Inertial Measurement Unit (IMU) presence
198 [6] 0: a projector, 1: an LED
203 [7] Image format codes per video streaming interface: