Struct v4l::device::Device

pub struct Device { /* fields omitted */ }

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, id: u32) -> Result<Control>

Returns the control value for an ID

Arguments

• id - Control identifier

pub fn set_control(&self, id: u32, val: Control) -> Result<()>

Modifies the control value

Arguments

• id - Control identifier
• val - New value

Trait Implementations

impl Capture for Device

pub 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

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

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

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

Returns a vector of valid formats for this device

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

Returns the format currently in use

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

Modifies the capture format and returns the actual format

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

Returns the parameters currently in use

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

Modifies the capture parameters and returns the actual parameters

impl Output for Device

pub 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

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

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

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

Returns a vector of valid formats for this device

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

Returns the format currently in use

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

Modifies the capture format and returns the actual format

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

Returns the parameters currently in use

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

Modifies the output parameters and returns the actual parameters

impl Read for Device

pub 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.

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

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

pub 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.

pub unsafe fn initializer(&self) -> Initializer

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

Determines if this Reader can work with buffers of uninitialized memory.

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

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

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

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

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

Read the exact number of bytes required to fill buf.

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

Creates a "by reference" adaptor for this instance of Read.

pub fn bytes(self) -> Bytes<Self>

Transforms this Read instance to an Iterator over its bytes.

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

Creates an adaptor which will chain this stream with another.

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

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

impl Write for Device

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

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

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

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

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

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

pub 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.

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

Attempts to write an entire buffer into this writer.

pub 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.

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

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

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

Creates a "by reference" adaptor for this instance of Write.