Well it&#39;s all about time. FFMpeg uses in fact three different timestamps in different bases in order to work. 

 - **tbn** = the time base in AVStream that has come from the container
 - **tbc** = the time base in AVCodecContext for the codec used for a particular stream
 - **tbr** = tbr is guessed from the video stream and is the value users
   want to see
       when they look for the video frame rate

This was also asked on the FFmpeg mailing lists: [What does the output of ffmpeg mean? tbr tbn tbc etc?](http://ffmpeg-users.933282.n4.nabble.com/What-does-the-output-of-ffmpeg-mean-tbr-tbn-tbc-etc-td941538.html)

I understand that `IValidatableObject` is used to validate an object in a way that lets one compare properties against each other.  

I&#39;d still like to have attributes to validate individual properties, but I want to ignore failures on some properties in certain cases.

Am I trying to use it incorrectly in the case below?  If not how do I implement this?

    public class ValidateMe : IValidatableObject
    {
        [Required]
        public bool Enable { get; set; }

        [Range(1, 5)]
        public int Prop1 { get; set; }

        [Range(1, 5)]
        public int Prop2 { get; set; }

        public IEnumerable&lt;ValidationResult&gt; Validate(ValidationContext validationContext)
        {
            if (!this.Enable)
            {
                /* Return valid result here.
                 * I don&#39;t care if Prop1 and Prop2 are out of range
                 * if the whole object is not &quot;enabled&quot;
                 */
            }
            else
            {
                /* Check if Prop1 and Prop2 meet their range requirements here
                 * and return accordingly.
                 */ 
            }
        }
    }



How do I use IValidatableObject?

I’ve read that you can disable (make physically unclickable) an HTML button simply by appending `disable` to its tag, but not as an attribute, as follows:

    &lt;input type=&quot;button&quot; name=myButton value=&quot;disable&quot; disabled&gt;

Since this setting is not an attribute, how can I add this in dynamically via JavaScript to disable a button that was previously enabled?

How to disable HTML button using JavaScript?

I am using ffmpeg to tell me video info. Specifically:

    ffmpeg -i video.ext

I get the output:

    Stream #0.0[0x1e0]: Video: mpeg2video, yuv420p, 704x576 [PAR 12:11 DAR 4:3], 9578 kb/s, 25 tbr, 90k tbn, 50 tbc

Does anyone know what tbr, tbn and tbc are exactly? I have seen speculation on the net but nothing definitive?

Meaning of ffmpeg output (tbc, tbn, tbr)

I am using ffmpeg to tell me video info. Specifically:
<pre><code class="hljs language-css">ffmpeg -i video.ext
</code></pre>
I get the output:
<pre><code class="hljs language-less">Stream #0.0[0x1e0]: Video: mpeg2video, yuv420p, 704x576 [PAR 12:11 DAR 4:3], 9578 kb/s, 25 tbr, 90k tbn, 50 tbc
</code></pre>
Does anyone know what tbr, tbn and tbc are exactly? I have seen speculation on the net but nothing definitive?

Does anyone know about any software that can convert video (avi, flv, whatever) to HTML5 supported ogg/ogv and mpeg4 formats?

I tried a few but I couldn&#39;t find anything that actually works.

Converting video to HTML5 ogg / ogv and mpg4

I need a list of codecs and formats supported by FFmpeg. Where can I find it?

What are all codecs and formats supported by FFmpeg?

I can&#39;t work out how to autoplay a video using the [new embed code style for Youtube][1]. I tried adding &amp;autoplay=1 to the url, which worked with the old style, but it didn&#39;t work. For example, [http://www.youtube.com/embed/JW5meKfy3fY][2] is the embed link, but [http://www.youtube.com/embed/JW5meKfy3fY&amp;autoplay=1][3] doesn&#39;t work. Can anyone tell me how to do it? Thanks


  [1]: http://apiblog.youtube.com/2010/07/new-way-to-embed-youtube-videos.html?utm_source=feedburner&amp;utm_medium=feed&amp;utm_campaign=Feed%3A+YoutubeApiBlog+%28YouTube+API+Blog%29&amp;utm_content=Google+Reader
  [2]: http://www.youtube.com/embed/JW5meKfy3fY
  [3]: http://www.youtube.com/embed/JW5meKfy3fY&amp;autoplay=1

How can I autoplay a video using the new embed code style for Youtube?

I have a set of video frames saved as images in a directory, and I&#39;m trying to encode these to a good quality video, however every setting and every format I try produces very noticeable artifacts.

The basic command is this:

    ffmpeg -r 25 -i %4d.png myvideo.mpg

and I&#39;ve tried the minrate and maxrate flags. Any of {mpg, avi, mov, flv} formats will do.

Any suggestions for settings? Final file size is not an issue.

Using ffmpeg to encode a high quality video

I&#39;ve created an HTML5 video player (very simple) that works perfectly on the iPad and the browser.

However, when I open it on the iPhone, I only get a play button which, when pressed, opens the native video player on a new window, on top of all my stuff.

That means I lose access to my custom controls and time tracking (written in Javascript), since the video is now running isolated.

Is there any way to override Apple&#39;s control of HTML5 video on the iphone and get it working like on the ipad?

Cheers

HTML5 inline video on iPhone vs iPad/Browser

I need to convert audio files to mp3 using ffmpeg.

When I write the command as `ffmpeg -i audio.ogg -acodec mp3 newfile.mp3`, I get the error:

    FFmpeg version 0.5.2, Copyright (c) 2000-2009 Fabrice Bellard, et al.
      configuration: 
      libavutil     49.15. 0 / 49.15. 0
      libavcodec    52.20. 1 / 52.20. 1
      libavformat   52.31. 0 / 52.31. 0
      libavdevice   52. 1. 0 / 52. 1. 0
      built on Jun 24 2010 14:56:20, gcc: 4.4.1
    Input #0, mp3, from &#39;ZHRE.mp3&#39;:
      Duration: 00:04:12.52, start: 0.000000, bitrate: 208 kb/s
        Stream #0.0: Audio: mp3, 44100 Hz, stereo, s16, 256 kb/s
    Output #0, mp3, to &#39;audio.mp3&#39;:
        Stream #0.0: Audio: 0x0000, 44100 Hz, stereo, s16, 64 kb/s
    Stream mapping:
      Stream #0.0 -&gt; #0.0
    Unsupported codec for output stream #0.0

I also ran this command:

     ffmpeg -formats | grep mp3

and got this in response:

    FFmpeg version 0.5.2, Copyright (c) 2000-2009 Fabrice Bellard, et al.
      configuration: 
      libavutil     49.15. 0 / 49.15. 0
      libavcodec    52.20. 1 / 52.20. 1
      libavformat   52.31. 0 / 52.31. 0
      libavdevice   52. 1. 0 / 52. 1. 0
      built on Jun 24 2010 14:56:20, gcc: 4.4.1
     DE mp3             MPEG audio layer 3
     D A    mp3             MP3 (MPEG audio layer 3)
     D A    mp3adu          ADU (Application Data Unit) MP3 (MPEG audio layer 3)
     D A    mp3on4          MP3onMP4
     text2movsub remove_extra noise mov2textsub mp3decomp mp3comp mjpegadump imxdump h264_mp4toannexb dump_extra

I guess that the mp3 codec isn&#39;t installed. Am I on the right track here?



Convert audio files to mp3 using ffmpeg

I have been trying to figure out how to rotate videos with FFmpeg. I am working with iPhone videos taken in portrait mode. I know how to determine the current degrees of rotation using [MediaInfo][1] (excellent library, btw) but I&#39;m stuck on FFmpeg now.

From what I&#39;ve read, what you need to use is a **vfilter** option. According to what I see, it should look like this:

    ffmpeg -vfilters &quot;rotate=90&quot; -i input.mp4 output.mp4

However, I can&#39;t get this to work. First, **-vfilters** doesn&#39;t exist anymore, it&#39;s now just **-vf**. Second, I get this error:

    No such filter: &#39;rotate&#39;
    Error opening filters!

As far as I know, I have an all-options-on build of FFmpeg. Running ***ffmpeg -filters*** shows this:

    Filters:
    anull            Pass the source unchanged to the output.
    aspect           Set the frame aspect ratio.
    crop             Crop the input video to x:y:width:height.
    fifo             Buffer input images and send them when they are requested.
    format           Convert the input video to one of the specified pixel formats.
    hflip            Horizontally flip the input video.
    noformat         Force libavfilter not to use any of the specified pixel formats
     for the input to the next filter.
    null             Pass the source unchanged to the output.
    pad              Pad input image to width:height[:x:y[:color]] (default x and y:
     0, default color: black).
    pixdesctest      Test pixel format definitions.
    pixelaspect      Set the pixel aspect ratio.
    scale            Scale the input video to width:height size and/or convert the i
    mage format.
    slicify          Pass the images of input video on to next video filter as multi
    ple slices.
    unsharp          Sharpen or blur the input video.
    vflip            Flip the input video vertically.
    buffer           Buffer video frames, and make them accessible to the filterchai
    n.
    color            Provide an uniformly colored input, syntax is: [color[:size[:ra
    te]]]
    nullsrc          Null video source, never return images.
    nullsink         Do absolutely nothing with the input video.

Having the options for **vflip** and **hflip** are great and all, but they just won&#39;t get me where I need to go. I need to the ability to rotate videos 90 degrees at the very least. 270 degrees would be an excellent option to have as well. Where have the rotate options gone?


  [1]: http://mediainfo.sourceforge.net/en

Rotating videos with FFmpeg

I would like to create an h264 or divx movie from frames that I generate in a python script in matplotlib. There are about 100k frames in this movie.

In examples on the web [eg. 1], I have only seen the method of saving each frame as a png and then running mencoder or ffmpeg on these files. In my case, saving each frame is impractical. Is there a way to take a plot generated from matplotlib and pipe it directly to ffmpeg, generating no intermediate files? 

Programming with ffmpeg&#39;s C-api is too difficult for me [eg. 2]. Also, I need an encoding that has good compression such as x264 as the movie file will otherwise be too large for a subsequent step. So it would be great to stick with mencoder/ffmpeg/x264.

Is there something that can be done with pipes [3]?

[1] http://matplotlib.sourceforge.net/examples/animation/movie_demo.html

[2] https://stackoverflow.com/questions/2940671

[3] http://www.ffmpeg.org/ffmpeg-doc.html#SEC41




Content Type	Original Author	Original Content on Stackoverflow
Question	user7289	View Question on Stackoverflow
Solution 1 - Video	Oleiade	View Answer on Stackoverflow

Meaning of ffmpeg output (tbc, tbn, tbr)

Video Problem Overview

Video Solutions

Solution 1 - Video

How to disable HTML button using JavaScript?

How do I use IValidatableObject?

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