Set/Get Video Properties

Set or get the values of various properties of the Video or Stream object.

Usage

# S3 method for class 'Rcpp_Stream'
setProp(x, property, value)

# S3 method for class 'Rcpp_Stream'
getProp(x, property)

# S3 method for class 'Rcpp_Video'
setProp(x, property, value)

# S3 method for class 'Rcpp_Video'
getProp(x, property)

# S3 method for class 'Rcpp_VideoWriter'
setProp(x, property, value)

# S3 method for class 'Rcpp_VideoWriter'
getProp(x, property)

setProp(x, property, value)

getProp(x, property)

Arguments

x: A Video or Stream object.
property: A character string specifying the name of the property to modify (see details below for a complete list).
value: The new value of the property.

Value

setProp returns TRUE is the property was set successfully. getProp returns a numeric value or a character string depending on property.

Note

Video properties are:

POS_MSEC:: Current position of the video file in milliseconds.
POS_FRAMES:: 0-based index of the frame to be decoded/captured next.
POS_AVI_RATIO:: Relative position of the video file: 0=start of the film, 1=end of the film.
FRAME_WIDTH:: Width in pixels of the frames in the video stream.
FRAME_HEIGHT:: Height in pixels of the frames in the video stream.
FPS:: Frame rate in frames per second.
FOURCC:: 4-character FOURCC code of the codec
FRAME_COUNT:: Number of frames in the video file.

Setting stream properties depends on a lot of things, mainly your operating system, the camera drivers installed on your computer and the camera itself. As a consequence, setting stream values might not work at all with your installation.

Stream properties are:

FRAME_WIDTH:: Width in pixels of the frames in the video stream.
FRAME_HEIGHT:: Height in pixels of the frames in the video stream.
BRIGHTNESS:: Brightness of the image
CONTRAST:: Contrast of the image
SATURATION:: Saturation of the image
HUE:: Hue of the image
GAIN:: Gain of the image
EXPOSURE:: Exposure

Author

Simon Garnier, garnier@njit.edu

Examples

balloon <- video(system.file("sample_vid/Balloon.mp4", package = "Rvision"))
#> Error: Could not open the video.
getProp(balloon, "FPS")
#> Error in eval(expr, envir, enclos): object 'balloon' not found
setProp(balloon, "POS_FRAMES", 25)
#> Error in eval(expr, envir, enclos): object 'balloon' not found