Struct opencv::videoio::VideoWriter

pub struct VideoWriter { /* fields omitted */ }

Video writer class.

The class provides C++ API for writing video files or image sequences.

Implementations

impl VideoWriter

pub fn as_raw_VideoWriter(&self) -> *const c_void

pub fn as_raw_mut_VideoWriter(&mut self) -> *mut c_void

impl VideoWriter

pub fn default() -> Result<VideoWriter>

Default constructors

The constructors/functions initialize video writers.

• On Linux FFMPEG is used to write videos;
• On Windows FFMPEG or MSWF or DSHOW is used;
• On MacOSX AVFoundation is used.

pub fn new(
    filename: &str,
    fourcc: i32,
    fps: f64,
    frame_size: Size,
    is_color: bool
) -> Result<VideoWriter>

Default constructors

The constructors/functions initialize video writers.

• On Linux FFMPEG is used to write videos;
• On Windows FFMPEG or MSWF or DSHOW is used;
• On MacOSX AVFoundation is used.

Overloaded parameters

Parameters

• filename: Name of the output video file.

• fourcc: 4-character code of codec used to compress the frames. For example, VideoWriter::fourcc(‘P’,‘I’,‘M’,‘1’) is a MPEG-1 codec, VideoWriter::fourcc(‘M’,‘J’,‘P’,‘G’) is a motion-jpeg codec etc. List of codes can be obtained at Video Codecs by FOURCC page. FFMPEG backend with MP4 container natively uses other values as fourcc code: see ObjectType, so you may receive a warning message from OpenCV about fourcc code conversion.

• fps: Framerate of the created video stream.

• frameSize: Size of the video frames.

• isColor: If it is not zero, the encoder will expect and encode color frames, otherwise it will work with grayscale frames.

  @b Tips:

  • With some backends fourcc=-1 pops up the codec selection dialog from the system.
  • To save image sequence use a proper filename (eg. img_%02d.jpg) and fourcc=0 OR fps=0. Use uncompressed image format (eg. img_%02d.BMP) to save raw frames.
  • Most codecs are lossy. If you want lossless video file you need to use a lossless codecs (eg. FFMPEG FFV1, Huffman HFYU, Lagarith LAGS, etc…)
  • If FFMPEG is enabled, using codec=0; fps=0; you can create an uncompressed (raw) video file.

C++ default parameters

• is_color: true

pub fn new_with_backend(
    filename: &str,
    api_preference: i32,
    fourcc: i32,
    fps: f64,
    frame_size: Size,
    is_color: bool
) -> Result<VideoWriter>

Default constructors

The constructors/functions initialize video writers.

• On Linux FFMPEG is used to write videos;
• On Windows FFMPEG or MSWF or DSHOW is used;
• On MacOSX AVFoundation is used.

Overloaded parameters

The apiPreference parameter allows to specify API backends to use. Can be used to enforce a specific reader implementation if multiple are available: e.g. cv::CAP_FFMPEG or cv::CAP_GSTREAMER.

C++ default parameters

• is_color: true

pub fn new_1(
    filename: &str,
    fourcc: i32,
    fps: f64,
    frame_size: Size,
    params: &Vector<i32>
) -> Result<VideoWriter>

Default constructors

The constructors/functions initialize video writers.

• On Linux FFMPEG is used to write videos;
• On Windows FFMPEG or MSWF or DSHOW is used;
• On MacOSX AVFoundation is used.

Overloaded parameters

 * The `params` parameter allows to specify extra encoder parameters encoded as pairs (paramId_1, paramValue_1, paramId_2, paramValue_2, ... .)
 * see cv::VideoWriterProperties

pub fn new_2(
    filename: &str,
    api_preference: i32,
    fourcc: i32,
    fps: f64,
    frame_size: Size,
    params: &Vector<i32>
) -> Result<VideoWriter>

Default constructors

The constructors/functions initialize video writers.

• On Linux FFMPEG is used to write videos;
• On Windows FFMPEG or MSWF or DSHOW is used;
• On MacOSX AVFoundation is used.

Overloaded parameters

pub fn fourcc(c1: i8, c2: i8, c3: i8, c4: i8) -> Result<i32>

Concatenates 4 chars to a fourcc code

Returns

a fourcc code

This static method constructs the fourcc code of the codec to be used in the constructor VideoWriter::VideoWriter or VideoWriter::open.

Trait Implementations

impl Boxed for VideoWriter

unsafe fn from_raw(ptr: *mut c_void) -> Self

Wrap the specified raw pointer

fn into_raw(self) -> *mut c_void

Return an the underlying raw pointer while consuming this wrapper.

fn as_raw(&self) -> *const c_void

Return the underlying raw pointer.

fn as_raw_mut(&mut self) -> *mut c_void

Return the underlying mutable raw pointer

impl Drop for VideoWriter

fn drop(&mut self)

Executes the destructor for this type.

impl Send for VideoWriter

impl VideoWriterTrait for VideoWriter

fn as_raw_VideoWriter(&self) -> *const c_void

fn as_raw_mut_VideoWriter(&mut self) -> *mut c_void

fn open(
    &mut self,
    filename: &str,
    fourcc: i32,
    fps: f64,
    frame_size: Size,
    is_color: bool
) -> Result<bool>

Initializes or reinitializes video writer.

fn open_with_backend(
    &mut self,
    filename: &str,
    api_preference: i32,
    fourcc: i32,
    fps: f64,
    frame_size: Size,
    is_color: bool
) -> Result<bool>

Initializes or reinitializes video writer.

fn open_1(
    &mut self,
    filename: &str,
    fourcc: i32,
    fps: f64,
    frame_size: Size,
    params: &Vector<i32>
) -> Result<bool>

Initializes or reinitializes video writer.

fn open_2(
    &mut self,
    filename: &str,
    api_preference: i32,
    fourcc: i32,
    fps: f64,
    frame_size: Size,
    params: &Vector<i32>
) -> Result<bool>

Initializes or reinitializes video writer.

fn is_opened(&self) -> Result<bool>

Returns true if video writer has been successfully initialized.

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

Closes the video writer.

fn write(&mut self, image: &dyn ToInputArray) -> Result<()>

Writes the next video frame

fn set(&mut self, prop_id: i32, value: f64) -> Result<bool>

Sets a property in the VideoWriter.

fn get(&self, prop_id: i32) -> Result<f64>

Returns the specified VideoWriter property

fn get_backend_name(&self) -> Result<String>

Returns used backend API name