Struct VideoWriter 

pub struct VideoWriter { /* private fields */ }

Video writer class.

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

Implementations

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 MSDN page or with this page of the fourcc site for a more complete list). 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.
• If FFMPEG is used, we allow frames of odd width or height, but in this case we truncate the rightmost column/the bottom row. Probably, this should be handled more elegantly, but some internal functions inside FFMPEG swscale require even width/height.

C++ default parameters

• is_color: true

pub fn new_def( filename: &str, fourcc: i32, fps: f64, frame_size: Size, ) -> 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 MSDN page or with this page of the fourcc site for a more complete list). 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.
• If FFMPEG is used, we allow frames of odd width or height, but in this case we truncate the rightmost column/the bottom row. Probably, this should be handled more elegantly, but some internal functions inside FFMPEG swscale require even width/height.

Note

This alternative version of [new] function uses the following default values for its arguments:

• 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_with_backend_def( filename: &str, api_preference: i32, fourcc: i32, fps: f64, frame_size: Size, ) -> 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.

Note

This alternative version of [new_with_backend] function uses the following default values for its arguments:

• 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: char, c2: char, c3: char, c4: char) -> 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: <VideoWriter as OpenCVFromExtern>::ExternReceive, ) -> Self

Wrap the specified raw pointer

fn into_raw(self) -> <VideoWriter as OpenCVTypeExternContainer>::ExternSendMut

Return the underlying raw pointer while consuming this wrapper.

fn as_raw(&self) -> <VideoWriter as OpenCVTypeExternContainer>::ExternSend

Return the underlying raw pointer.

fn as_raw_mut( &mut self, ) -> <VideoWriter as OpenCVTypeExternContainer>::ExternSendMut

Return the underlying mutable raw pointer

impl Debug for VideoWriter

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Drop for VideoWriter

fn drop(&mut self)

Executes the destructor for this type.

impl VideoWriterTrait for VideoWriter

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_def( &mut self, filename: &str, fourcc: i32, fps: f64, frame_size: Size, ) -> 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_with_backend_def( &mut self, filename: &str, api_preference: i32, fourcc: i32, fps: f64, frame_size: Size, ) -> 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 release(&mut self) -> Result<()>

Closes the video writer.

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

Writes the next video frame

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

Sets a property in the VideoWriter.

impl VideoWriterTraitConst for VideoWriter

fn as_raw_VideoWriter(&self) -> *const c_void

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

Returns true if video writer has been successfully initialized.

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

impl Send for VideoWriter