hasFrame

Determine if video frame is available to read

Syntax

tf = hasFrame(v)

Description

tf = hasFrame(v) returns logical 1 (true) if there is a video frame available to read from the file. Otherwise, it returns logical 0 (false).

Examples

Create VideoReader Object and Read Video

Create a VideoReader object for the example movie file xylophone.mp4.

v = VideoReader('xylophone.mp4');

Read all the frames from the video, one frame at a time.

while hasFrame(v)
    frame = readFrame(v);
end

Display information about the last frame returned by readFrame.

whos frame

  Name         Size                Bytes  Class    Attributes

  frame      240x320x3            230400  uint8              

Read and Play Back Movie File

Read and play back the sample movie file, xylophone.mp4.

Create a VideoReader object to read data from the sample file. Then, determine the width and height of the video.

xyloObj = VideoReader('xylophone.mp4');

vidWidth = xyloObj.Width;
vidHeight = xyloObj.Height;

Create a movie structure array, mov.

mov = struct('cdata',zeros(vidHeight,vidWidth,3,'uint8'),...
    'colormap',[]);

Read one frame at a time until the end of the video is reached.

k = 1;
while hasFrame(xyloObj)
    mov(k).cdata = readFrame(xyloObj);
    k = k+1;
end

Size a figure based on the width and height of the video. Then, play back the movie once at the video frame rate.

hf = figure;
set(hf,'position',[150 150 vidWidth vidHeight]);

movie(hf,mov,1,xyloObj.FrameRate);

Input Arguments

v — Input VideoReader object

VideoReader object

Input VideoReader object. Use the VideoReader function to create a VideoReader object from your video file.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

Version History

Introduced in R2014b