Struct v4l::device::Device

pub struct Device { /* private fields */ }

Linux capture device abstraction

Implementations

impl Device

pub fn new(index: usize) -> Result<Self>

Returns a capture device by index

Devices are usually enumerated by the system. An index of zero thus represents the first device the system got to know about.

Arguments

• index - Index (0: first, 1: second, ..)

Example

use v4l::device::Device;
let dev = Device::new(0);

pub fn with_path<P: AsRef<Path>>(path: P) -> Result<Self>

Returns a capture device by path

Linux device nodes are usually found in /dev/videoX or /sys/class/video4linux/videoX.

Arguments

• path - Path (e.g. “/dev/video0”)

Example

use v4l::device::Device;
let dev = Device::with_path("/dev/video0");

pub fn handle(&self) -> Arc<Handle>

Returns the raw device handle

pub fn query_caps(&self) -> Result<Capabilities>

Returns video4linux framework defined information such as card, driver, etc.

pub fn query_controls(&self) -> Result<Vec<Description>>

Returns the supported controls for a device such as gain, focus, white balance, etc.

pub fn control(&self, desc: &Description) -> Result<Control>

Returns the current control value from its Description

Arguments

• desc - Control description

pub fn set_control(&self, ctrl: Control) -> Result<()>

Modifies the control value

Arguments

• ctrl - Control to be set

pub fn set_controls(&self, ctrls: Vec<Control>) -> Result<()>

Modifies the control values atomically

Arguments

• ctrls - Vec of the controls to be set

Trait Implementations

impl Capture for Device

fn enum_frameintervals( &self, fourcc: FourCC, width: u32, height: u32, ) -> Result<Vec<FrameInterval>>

Returns a vector of all frame intervals that the device supports for the given pixel format and frame size

fn enum_framesizes(&self, fourcc: FourCC) -> Result<Vec<FrameSize>>

Returns a vector of valid framesizes that the device supports for the given pixel format

fn enum_formats(&self) -> Result<Vec<FormatDescription>>

Returns a vector of valid formats for this device

fn format(&self) -> Result<Format>

Returns the format currently in use

fn set_format(&self, fmt: &Format) -> Result<Format>

Modifies the capture format and returns the actual format

fn params(&self) -> Result<Parameters>

Returns the parameters currently in use

fn set_params(&self, params: &Parameters) -> Result<Parameters>

Modifies the capture parameters and returns the actual parameters

impl Output for Device

fn enum_frameintervals( &self, fourcc: FourCC, width: u32, height: u32, ) -> Result<Vec<FrameInterval>>

Returns a vector of all frame intervals that the device supports for the given pixel format and frame size

fn enum_framesizes(&self, fourcc: FourCC) -> Result<Vec<FrameSize>>

Returns a vector of valid framesizes that the device supports for the given pixel format

fn enum_formats(&self) -> Result<Vec<FormatDescription>>

Returns a vector of valid formats for this device

fn format(&self) -> Result<Format>

Returns the format currently in use

fn set_format(&self, fmt: &Format) -> Result<Format>

Modifies the capture format and returns the actual format

fn params(&self) -> Result<Parameters>

Returns the parameters currently in use

fn set_params(&self, params: &Parameters) -> Result<Parameters>

Modifies the output parameters and returns the actual parameters

impl Read for Device

fn read(&mut self, buf: &mut [u8]) -> Result<usize>

Pull some bytes from this source into the specified buffer, returning how many bytes were read.

fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> Result<usize, Error>

Like read, except that it reads into a slice of buffers.

fn is_read_vectored(&self) -> bool

🔬This is a nightly-only experimental API. (can_vector)

Determines if this Reader has an efficient read_vectored implementation.

fn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize, Error>

Reads all bytes until EOF in this source, placing them into buf.

fn read_to_string(&mut self, buf: &mut String) -> Result<usize, Error>

Reads all bytes until EOF in this source, appending them to buf.

fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), Error>

Reads the exact number of bytes required to fill buf.

fn read_buf(&mut self, buf: BorrowedCursor<'_>) -> Result<(), Error>

🔬This is a nightly-only experimental API. (read_buf)

Pull some bytes from this source into the specified buffer.

fn read_buf_exact(&mut self, cursor: BorrowedCursor<'_>) -> Result<(), Error>

🔬This is a nightly-only experimental API. (read_buf)

Reads the exact number of bytes required to fill cursor.

fn by_ref(&mut self) -> &mut Self

where Self: Sized,

Creates a “by reference” adaptor for this instance of Read.

fn bytes(self) -> Bytes<Self>

where Self: Sized,

Transforms this Read instance to an Iterator over its bytes.

fn chain<R>(self, next: R) -> Chain<Self, R>

where R: Read, Self: Sized,

Creates an adapter which will chain this stream with another.

fn take(self, limit: u64) -> Take<Self>

where Self: Sized,

Creates an adapter which will read at most limit bytes from it.

impl Write for Device

fn write(&mut self, buf: &[u8]) -> Result<usize>

Writes a buffer into this writer, returning how many bytes were written.

fn flush(&mut self) -> Result<()>

Flushes this output stream, ensuring that all intermediately buffered contents reach their destination.

fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> Result<usize, Error>

Like write, except that it writes from a slice of buffers.

fn is_write_vectored(&self) -> bool

🔬This is a nightly-only experimental API. (can_vector)

Determines if this Writer has an efficient write_vectored implementation.

fn write_all(&mut self, buf: &[u8]) -> Result<(), Error>

Attempts to write an entire buffer into this writer.

fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<(), Error>

🔬This is a nightly-only experimental API. (write_all_vectored)

Attempts to write multiple buffers into this writer.

fn write_fmt(&mut self, fmt: Arguments<'_>) -> Result<(), Error>

Writes a formatted string into this writer, returning any error encountered.

fn by_ref(&mut self) -> &mut Self

where Self: Sized,

Creates a “by reference” adapter for this instance of Write.