I ended up using [ffmpeg][1] and [ffmpeg2theora][2].

### WebKit compatible h.264 video

I decided to go for the ipod640 preset because it means the video can be viewed nicely on an iPhone or iPod touch. Of course, you can change the settings around a bit, get rid of the &#39;-vpre ipod640&#39;, change the resolution or quality. Anyway the command is:

`ffmpeg -i video_source_file.ext -vcodec libx264 -vpre ipod640 -b 250k -bt 50k -acodec libfaac -ab 56k -ac 2 -s 480x320 video_out_file.mp4`

move some information to the front of the file so the video can play before it loads

`qt-faststart video_out_file.mp4 video_out_file_quickstart.mp4`

### Firefox compatible Ogg video

This depends on you having ffmpeg2theora installed. Also, I have only tested it with the input file being the output file from the previous ffmpeg conversion. The command is:

`ffmpeg2theora -o video_out_file.ogv video_out_file.mp4`


  [1]: http://ffmpeg.org/
  [2]: http://v2v.cc/~j/ffmpeg2theora/

How can I find the location of my application&#39;s executable in WPF (C# or VB.Net)?

I&#39;ve used this code with windows forms:

    Application.ExecutablePath.ToString();

But with WPF I received this error from Visual Studio: 

&gt; System.Window.Application does not contain a definition for ExecutablePath.

Find the location of my application&#39;s executable in WPF (C# or vb.net)?

Is there any API by which we can get CPU or Memory usage of android?

I have tried one code as below:

    package com.infostretch.mainactivity;

    import java.io.BufferedReader;
    import java.io.FileInputStream;
    import java.io.IOException;
    import java.io.InputStreamReader;

    public class CPULoad 
    {
        long total = 0;
        long idle = 0;

        float usage = 0;

        public CPULoad()
        {
            readUsage();
        }

        public float getUsage()
        {
            readUsage();
            return usage;
        }

        private void readUsage()
        {
            try
            {
                BufferedReader reader = new BufferedReader(new InputStreamReader(new FileInputStream(&quot;/proc/stat&quot;)), 1000);
                String load = reader.readLine();
                reader.close();

                String[] toks = load.split(&quot; &quot;);

                long currTotal = Long.parseLong(toks[2]) + Long.parseLong(toks[3]) + Long.parseLong(toks[4]);
                long currIdle = Long.parseLong(toks[5]);

                this.usage = (currTotal - total) * 100.0f / (currTotal - total + currIdle - idle);
                this.total = currTotal;
                this.idle = currIdle;
            }
            catch(IOException ex)
            {
                ex.printStackTrace();
            }
        }
    }

Is this the correct way to do it?

Get Memory Usage in Android

Despite all the hype, in reality the HTML5 video tag has a bit of a problem. In order to use it and for it to be cross browser compatible, you have to include more than one format of the video. To target all supported browsers these formats are mp4 and ogg. 

I was searching around for optimum settings for each format but unfortunately I couldn&#39;t find any. I&#39;m using ffmpeg 0.6 which has the tagline &quot;Works with HTML5&quot;. I&#39;m no video expert so I was wondering if anyone could recommend decent settings for each format? 

ffmpeg settings for converting to mp4 and ogg for HTML5 video

<p>Despite all the hype, in reality the HTML5 video tag has a bit of a problem. In order to use it and for it to be cross browser compatible, you have to include more than one format of the video. To target all supported browsers these formats are mp4 and ogg.</p>
<p>I was searching around for optimum settings for each format but unfortunately I couldn't find any. I'm using ffmpeg 0.6 which has the tagline "Works with HTML5". I'm no video expert so I was wondering if anyone could recommend decent settings for each format?</p>


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)

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

So, I have an SVG file in HTML, and one of the things I&#39;ve heard about the format is that it doesn&#39;t get all pixelated when you zoom in on it.

I know with a jpeg or whatever I could have it stored as a 50 by 50 icon, then actually display it as a (rather pixelated) 100 by 100 thumbnail (or 10 by 10), by manually setting the height and width in the image_src tag.

However, SVG files seem to be used with object/embed tags, and changing the height or width of THOSE just results in more space being allocated for the picture.

IS there any way to specify that you want an SVG image displayed smaller or larger than it actually is stored in the file system?



Resizing SVG in html?

In IE, I can use:

    &lt;img src=&quot;http://example.com/image.png&quot; style=&quot;filter:FlipH&quot;&gt;

to implement an image flip horizontally.

Is there any way to flip horizontally in HTML5? (maybe by using canvas?)

thanks all :)

How to flip images horizontally with HTML5

I am currently doing a project, in which I need to stop the user from taking the snapshot of any Web Page, for which he can use the &quot;Print Scrn&quot; / &quot;Printscreen&quot; key available in any of the normal keyboards.

I have been trying to find its solution, but in vain. If possible, I need to take into account of the &quot;**Screengrab**&quot; add-on of the Firefox browser, by stopping it also.  

Any help is greatly appreciated, and I am using PHP (as server-side language) &amp; jQuery for my project.

Stop User from using &quot;Print Scrn&quot; / &quot;Printscreen&quot; key of the Keyboard for any Web Page

I got a rails app where I can input a few paragraphs of text into my model.  The problem is I dont know how to input any line breaks.

I&#39;ve tried to add &quot; {ln}{/ln} ;  {&amp;nbsp}  and {br}{/br}&quot;  but that only displays the html as text and no break.

Is there anyway I can set it so the text area control will use any of the html I place within the model entry?

Is there any thing I can type so rails will recognize, hey put a line here?



Rails -- Add a line break into a text area

So, I was thinking I could just loop through localStorage like a normal object as it has a length. How can I loop through this?

    localStorage.setItem(1,&#39;Lorem&#39;);
    localStorage.setItem(2,&#39;Ipsum&#39;);
    localStorage.setItem(3,&#39;Dolor&#39;);

If I do a `localStorage.length` it returns `3` which is correct. So I&#39;d assume a `for...in` loop would work.

I was thinking something like:

    for (x in localStorage){
	    console.log(localStorage[x]);
    }

But no avail. Any ideas?

The other idea I had was something like

    localStorage.setItem(1,&#39;Lorem|Ipsum|Dolor&#39;)
    var split_list = localStorage.getItem(1).split(&#39;|&#39;);

In which the `for...in` does work.

Looping through localStorage in HTML5 and JavaScript

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

We filmed a spokesperson on a green screen and have the video files ready in multiple formats. 

With Flash we could use the wmode transparent within the param and embed tags, but is there something similar to this with the video and source tags in HTML5? Is it even possible to properly save .m4v or .ogv videos so that we can play these files with transparent backgrounds on our browsers?

Thanks

Can I have a video with transparent background using HTML5 video tag?

I&#39;m trying to concatenate two mp4 files using ffmpeg.  I need this to be an automatic process hence why I chose ffmpeg.  I&#39;m converting the two files into `.ts` files and then concatenating them and then trying to encode that concatenated `.ts` file.  The files are `h264` and `aac` encoded and I&#39;m hoping to keep the quality the same or as close to original as possible.

    ffmpeg -i part1.mp4 -vcodec copy -vbsf h264_mp4toannexb -acodec copy part1.ts
    ffmpeg -i part2.mp4 -vcodec copy -vbsf h264_mp4toannexb -acodec copy part2.ts
    cat part1.ts part2.ts &gt; parts.ts
    ffmpeg -y -i parts.ts -acodec copy -ar 44100 -ab 96k -coder ac -vbsf h264_mp4toannexb parts.mp4

Unfortunately I&#39;m getting the following error message coming back from ffmpeg during encoding:

    [h264 @ 0x1012600]sps_id out of range
    [h264 @ 0x1012600]non-existing SPS 0 referenced in buffering period
    [h264 @ 0x1012600]sps_id out of range
    [h264 @ 0x1012600]non-existing SPS 0 referenced in buffering period
    [NULL @ 0x101d600]error, non monotone timestamps 13779431 &gt;= 13779431kbits/s    
    av_interleaved_write_frame(): Error while opening file

This happens about half way through encoding which makes me think that you can&#39;t concat two .ts files together and have it work.

How to concatenate two MP4 files using FFmpeg?

`ffmpeg -i infile.avi out.mp4` outputs non-fragmented MP4.

How do I obtain fragmented mp4?

**Update**
A fragmented mp4 file is internally divided into several back-to-back chunks or MPEG-4 movie fragments. Each chunk has its own moof atom - so there are several moof atoms interleaved in the file instead of a single moov at the end as in the case of an unfragmented mp4. This makes it easier to stream over slow networks where buffering is involved

There are several tools like [mp4box][1] that convert a normal mp4 to a fragmented one. Unfortunately we cannot use something like this

    ffmpeg &lt;options to output mp4&gt; | mp4box

since ffmpeg does not produce seekable output while producing mp4 containers.

  [1]: https://gpac.wp.mines-telecom.fr/2011/02/02/mp4box-fragmentation-segmentation-splitting-and-interleaving/

How to output fragmented mp4 with ffmpeg?

I am trying to add text subtitles to an .mp4 container using ffmpeg:

    ffmpeg -i input.mp4 -i input.srt -map 0.0 -map 0.1 -map 1.0 output.mp4

When I am trying to run this line, it gives me an error : 

&gt; Nmber of stream maps must match number of output streams. 

If I try to change the mp4 to mkv (although mp4 supports text subtitles), like this:

    ffmpeg -i input.mp4 -i input.srt -map 0.0 -map 0.1 -map 1.0 output.mkv

It correctly maps the streams, but gives an error :

&gt; Encoder (codec id 94210) not found for output stream #0.2 

When I launch

    ffmpeg -codecs

I can see that srt codec is supported as decoder and encoder, however I am not sure what is used for mp4 and mkv subs encoding, and whether I need to switch it on or compile separately.

Use ffmpeg to add text subtitles

I have a web page, which (among other things) needs to extract a specific frame from a user-uploaded video.  The user seeks to a particular part of a .mp4 in the player, then clicks a button, and an ajax call gets fired off to a php script which takes the .mp4, and the exact time from the video, and uses that to extract a &quot;thumbnail&quot; frame.

My current solution is using the php `exec` command:

`exec(&quot;ffmpeg -i $videoPath -ss $timeOffset -vframes 1 $jpgOutputPath&quot;);`

...which works just great, except it&#39;s as slow as molasses.  My guess is that ffmpeg is a little too much for the job, and I might be able to do better by utilizing the underlying libraries or something... however I have zero idea how to do that.

Ideally I don&#39;t want to have to install anything that requires a real &quot;installation process&quot;... i.e., dropping an executable into the folder with my web app is fine, but I&#39;d rather not have to actually run an installer.  Also, the solution should be able to run on mac, linux and windows (though linux is the top priority).

What can I do to speed this process up?

Thanks.

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

ffmpeg settings for converting to mp4 and ogg for HTML5 video

Video Problem Overview

Video Solutions

Solution 1 - Video

WebKit compatible h.264 video

Firefox compatible Ogg video

Get Memory Usage in Android

Find the location of my application's executable in WPF (C# or vb.net)?

Attributions