VIDIOC_DV_TIMINGS_CAP — The capabilities of the Digital Video receiver/transmitter
int fsfuncioctl( | int fd, |
int request, | |
struct v4l2_dv_timings_cap *argp) ; |
This is an experimental interface and may change in the future.
To query the available timings, applications initialize the
index
field and zero the reserved array of struct v4l2_dv_timings_cap
and call the VIDIOC_DV_TIMINGS_CAP
ioctl with a pointer to this
structure. Drivers fill the rest of the structure or return an
EINVAL error code when the index is out of bounds. To enumerate all supported DV timings,
applications shall begin at index zero, incrementing by one until the
driver returns EINVAL. Note that drivers may enumerate a
different set of DV timings after switching the video input or
output.
Table A.18. struct v4l2_bt_timings_cap
__u32 | min_width | Minimum width of the active video in pixels. |
__u32 | max_width | Maximum width of the active video in pixels. |
__u32 | min_height | Minimum height of the active video in lines. |
__u32 | max_height | Maximum height of the active video in lines. |
__u64 | min_pixelclock | Minimum pixelclock frequency in Hz. |
__u64 | max_pixelclock | Maximum pixelclock frequency in Hz. |
__u32 | standards | The video standard(s) supported by the hardware. See Table A.57, “DV BT Timing standards” for a list of standards. |
__u32 | capabilities | Several flags giving more information about the capabilities. See Table A.20, “DV BT Timing capabilities” for a description of the flags. |
__u32 | reserved [16] |
Table A.19. struct v4l2_dv_timings_cap
__u32 | type | Type of DV timings as listed in Table A.56, “DV Timing types”. | |
__u32 | reserved [3] | Reserved for future extensions. Drivers must set the array to zero. | |
union |
| ||
struct v4l2_bt_timings_cap | bt | BT.656/1120 timings capabilities of the hardware. | |
__u32 | raw_data [32] |
Table A.20. DV BT Timing capabilities
Flag | Description |
V4L2_DV_BT_CAP_INTERLACED | Interlaced formats are supported. |
V4L2_DV_BT_CAP_PROGRESSIVE | Progressive formats are supported. |
V4L2_DV_BT_CAP_REDUCED_BLANKING | CVT/GTF specific: the timings can make use of reduced blanking (CVT) or the 'Secondary GTF' curve (GTF). |
V4L2_DV_BT_CAP_CUSTOM | Can support non-standard timings, i.e. timings not belonging to the
standards set in the standards field.
|
On success 0 is returned, on error -1 and the errno
variable is set appropriately. The generic error codes are described at the Generic Error Codes chapter.