Why Does VideoReader return an Empty Object With No Error?

Hello all.

I'm experiencing issues processing video files using VideoReader in matlab R2015a. The code works on my Ubuntu 16.04 machine, and my Windows 10 machine, so I believe the issue has something to do with the decoders installed in CentOS 6.8.

When I attempt to initialize a VideoReader object using a video file (.mp4, .avi, or .mov), I get this result:

>> v=VideoReader('1.avi')

v =

VideoReader with properties:

   General Properties:
            Name: '1.avi'
            Path: '/opt/home/fp/fp06/fp0634/videos'
        Duration: 0
     CurrentTime: 0
             Tag: ''
        UserData: []

   Video Properties:
           Width: 0
          Height: 0
       FrameRate: 0
    BitsPerPixel: 0
     VideoFormat: ''

However, if I attempt to analyze the .avi videos using aviinfo, I'm able to extract the metadata:

>> i=aviinfo('1.avi') Warning: AVIINFO will be removed in a future release. Use VIDEOREADER instead. > In aviinfo (line 66)

i =

              Filename: '/opt/home/fp/fp06/fp0634/videos/1.avi'
              FileSize: 36294688
           FileModDate: '02-Aug-2016 18:12:45'
             NumFrames: 7095
       FramesPerSecond: 30
                 Width: 1280
                Height: 720
             ImageType: 'truecolor'
      VideoCompression: 'FMP4'
               Quality: 4.2950e+07
    NumColormapEntries: 0
           AudioFormat: 'Format # 0x55'
             AudioRate: 44100
      NumAudioChannels: 2

The video files I am trying to work with are encoded using MPEG-4, and are of multiple types (specifically .mp4, .avi, and .mov). Matlab seems to recognize that they are video files, since I can use aviinfo on the .avi files, but VideoReader can not extract frames or metadata from them.

In order to solve this issue, I have consulted these articles on how to set up multimedia on CentOS: https://wiki.centos.org/TipsAndTricks/MultimediaOnCentOS7 https://wiki.centos.org/TipsAndTricks/MultimediaOnCentOS

I also looked at many webpages pertaining to similar issues, and they recommended checking that gstreamer0.10 and necessary plugins are installed. I double checked that gstreamer0.10 was installed on my system, and installed the gstreamer-ffmpeg plugin, but I still encounter the same issue.

Running 'yum search gstreamer' gives me these results:

    PackageKit-gstreamer-plugin.x86_64 : Install GStreamer codecs using PackageKit
    bluez-gstreamer.i686 : GStreamer support for SBC audio format
    bluez-gstreamer.x86_64 : GStreamer support for SBC audio format
    gstreamer.i686 : GStreamer streaming media framework runtime
    gstreamer.x86_64 : GStreamer streaming media framework runtime
    gstreamer-devel.i686 : Libraries/include files for GStreamer streaming media framework
    gstreamer-devel.x86_64 : Libraries/include files for GStreamer streaming media framework
    gstreamer-devel-docs.noarch : Developer documentation for GStreamer streaming media framework
    gstreamer-ffmpeg.i686 : GStreamer FFmpeg-based plug-ins
    gstreamer-ffmpeg.x86_64 : GStreamer FFmpeg-based plug-ins
    gstreamer-ffmpeg-debuginfo.x86_64 : Debug information for package gstreamer-ffmpeg
    gstreamer-java.x86_64 : Java interface to the gstreamer framework
    gstreamer-java-javadoc.x86_64 : Javadocs for gstreamer-java
    gstreamer-java-swt.x86_64 : SWT support for gstreamer-java
    gstreamer-plugins-bad.i686 : GStreamer streaming media framework "bad" plug-ins
    gstreamer-plugins-bad.x86_64 : GStreamer streaming media framework "bad" plug-ins
    gstreamer-plugins-bad-debuginfo.x86_64 : Debug information for package gstreamer-plugins-bad
    gstreamer-plugins-bad-free.i686 : GStreamer streaming media framework "bad" plug-ins
    gstreamer-plugins-bad-free.x86_64 : GStreamer streaming media framework "bad" plug-ins
    gstreamer-plugins-bad-free-devel.i686 : Development files for the GStreamer media framework "bad" plug-ins
    gstreamer-plugins-bad-free-devel.x86_64 : Development files for the GStreamer media framework "bad" plug-ins
    gstreamer-plugins-bad-free-devel-docs.x86_64 : Development documentation for the GStreamer "bad" plug-ins
    gstreamer-plugins-bad-free-extras.i686 : Extra GStreamer "bad" plugins (less often used "bad" plugins)
    gstreamer-plugins-bad-free-extras.x86_64 : Extra GStreamer "bad" plugins (less often used "bad" plugins)
    gstreamer-plugins-bad-freeworld-devel.i686 : Development files for the GStreamer "bad" plug-ins
    gstreamer-plugins-bad-freeworld-devel.x86_64 : Development files for the GStreamer "bad" plug-ins
    gstreamer-plugins-bad-nonfree.x86_64 : Non Free GStreamer streaming media framework "bad" plug-ins
    gstreamer-plugins-bad-nonfree-debuginfo.x86_64 : Debug information for package gstreamer-plugins-bad-nonfree
    gstreamer-plugins-base.i686 : GStreamer streaming media framework base plug-ins
    gstreamer-plugins-base.x86_64 : GStreamer streaming media framework base plug-ins
    gstreamer-plugins-base-devel.i686 : GStreamer Base Plugins Development files
    gstreamer-plugins-base-devel.x86_64 : GStreamer Base Plugins Development files
    gstreamer-plugins-base-devel-docs.noarch : Developer documentation for GStreamer Base plugins library
    gstreamer-plugins-good.i686 : GStreamer plug-ins with good code and licensing
    gstreamer-plugins-good.x86_64 : GStreamer plug-ins with good code and licensing
    gstreamer-plugins-good-devel.i686 : Dummy package to make gstreamer-plugins-good multilib
    gstreamer-plugins-good-devel.x86_64 : Dummy package to make gstreamer-plugins-good multilib
    gstreamer-plugins-ugly.i686 : GStreamer streaming media framework "ugly" plug-ins
    gstreamer-plugins-ugly.x86_64 : GStreamer streaming media framework "ugly" plug-ins
    gstreamer-plugins-ugly-debuginfo.x86_64 : Debug information for package gstreamer-plugins-ugly
    gstreamer-plugins-ugly-devel-docs.noarch : Development documentation for the GStreamer "ugly" plug-ins
    gstreamer-python.x86_64 : Python bindings for GStreamer
    gstreamer-python-devel.x86_64 : Headers for developing programs that will use gstreamer-python
    gstreamer-tools.x86_64 : common tools and files for GStreamer streaming media framework
    gstreamer1-libav.x86_64 : GStreamer 1.0 libav-based plug-ins
    gstreamer1-libav-debuginfo.x86_64 : Debug information for package gstreamer1-libav
    gstreamer1-plugins-bad-freeworld.x86_64 : GStreamer 1.0 streaming media framework "bad" plug-ins
    gstreamer1-plugins-bad-freeworld-debuginfo.x86_64 : Debug information for package gstreamer1-plugins-bad-freeworld
    gstreamer1-plugins-ugly.x86_64 : GStreamer 1.0 streaming media framework "ugly" plug-ins
    gstreamer1-plugins-ugly-debuginfo.x86_64 : Debug information for package gstreamer1-plugins-ugly
    gstreamer1-plugins-ugly-devel-docs.noarch : Development documentation for the GStreamer "ugly" plug-ins
    gstreamer1-vaapi.x86_64 : GStreamer plugins to use VA API video acceleration
    gstreamer1-vaapi-debuginfo.x86_64 : Debug information for package gstreamer1-vaapi
    gstreamer1-vaapi-devel.x86_64 : Development files for gstreamer1-vaapi
    phonon-backend-gstreamer.i686 : Gstreamer phonon backend
    phonon-backend-gstreamer.x86_64 : Gstreamer phonon backend
    qt-gstreamer.x86_64 : C++ bindings for GStreamer with a Qt-style API
    qt-gstreamer-debuginfo.x86_64 : Debug information for package qt-gstreamer
    qt-gstreamer-devel.x86_64 : Header files and development documentation for qt-gstreamer

I am unsure whether the issue is with matlab or CentOS (or both). Any advice regarding this issue is highly appreciated. Thank you for your time.

[Walter Roberson]

Does the metadata show up after you read one frame? Except for the duration, which might not be known until you have read all of the frames.

[Kalie H]

Hi Walter, thanks for your reply.

I am not able to read any frames from the video. When I call "read" on the object, I get this result:

>> v.read

ans =

     []

After doing so the object looks exactly the same as before when I evaluate it.