video read in matlab -audio output port is not relavant

Question

If i execute this statement or the similar videoFileWriter or even multimediafilereader in matlab 2012b

videoFileReadera = vision.VideoFileReader(filename,'AudioOutputPort',true);

i am getting warning as

Warning: The AudioOutputPort property is not relevant in this configuration of the System object.

or with AudioInputPort...

i know its just a warning but the object fails to read or write the audio file??

please tell me how to read a video and audio combined file and to write it back as a single video and audio combined file.

Answer 1

clear all;
close all;
clc;
VidObj=VideoReader('E:\workspace\mat2012b\video compression\original.mp4');
n=VidObj.NumberOfFrames;
videoFReader = vision.VideoFileReader('original.mp4');
videoFWriter = vision.VideoFileWriter('vid_new_compressed_ffd5.avi',...
   'AudioInputPort',1,'AudioDataType','int16','VideoCompressor','ffdshow video encoder','FileFormat','avi',...
   'FrameRate',videoFReader.info.VideoFrameRate);
[audio,fs]=audioread('original.mp4');
op=floor(fs/videoFReader.info.VideoFrameRate);

for i=1:n
    videoFrame= step(videoFReader);
    audios=audio( (i-1)*op + 1 : i*op , : );
    step(videoFWriter, videoFrame,audios);
end

release(videoFReader);
release(videoFWriter);

This above code reads an audio and video and writes back to audio and video. I tried to get .mp4 as output it didnt work. This code can give .avi and .wmv as output.