Short answer: No. Use WebM or Ogg instead.

[This article][1] covers just about everything you need to know about the `&lt;video&gt;` element, including which browsers support which container formats and codecs.

  [1]: http://diveintohtml5.info/video.html

There are three formats with a reasonable level of support: H.264 (MPEG-4 AVC), OGG Theora (VP3) and WebM (VP8). See the wiki linked by Sam for which browsers support which; you will typically need at least one of those plus Flash fallback.

Whilst most browsers won&#39;t touch AVI, there are some browser builds that expose all the multimedia capabilities of the underlying OS to `&lt;video&gt;`. These browser will indeed be able to play AVI, as long as they have matching codecs installed (AVI can contain about a million different video and audio formats). In particular Safari on OS X with QuickTime, or Konqi with GStreamer.

Personally I think this is an *absolutely disastrous* idea, as it exposes a very large codec codebase to the net, a codebase that was mostly not written to be resistant to network attacks. One of the worst drawbacks of media player plugins was the huge number of security holes they made available to every web page exploit. Let&#39;s not make this mistake again.

The current HTML5 draft specification does not specify which video formats browsers should support in the video tag. User agents are free to support any video formats they feel are appropriate.

http://en.wikipedia.org/wiki/HTML5_video

The HTML specification *never* specifies any content formats. That&#39;s not its job. There&#39;s plenty of standards organizations that are more qualified than the W3C to specify video formats.

That&#39;s what content negotiation is for.

* The HTML specification doesn&#39;t specify any image formats for the `&lt;img&gt;` element.
* The HTML specification doesn&#39;t specify any style sheet languages for the `&lt;style&gt;` element.
* The HTML specification doesn&#39;t specify any scripting languages for the `&lt;script&gt;` element.
* The HTML specification doesn&#39;t specify any object formats for the `&lt;object&gt;` and `embed` elements.
* The HTML specification doesn&#39;t specify any audio formats for the `&lt;audio&gt;` element.

Why should it specify one for the `&lt;video&gt;` element?

I have found many sites that describes PRG, but no simple PHP code example.

-----

Here&#39;s what I implemented:

1. The `form.php` has an action: `validate.php`.
1. The `validate.php` is never seen by the user; if validates all `$_GET` and, if valid writes it to database and generates the HTML of a confirmation page / if not valid, it generates the HTML of an error page explaining what is wrong. 
1. Whichever HTML is generated get stored in a `$_SESSION` variable and then `validate.php` calls `header(&#39;Location: &lt;as appropriate&gt;);`.
1. The `submitted.php` of `invalid_input.php` (in case the user reads the URL) consists only of `echo $_SESSION[&#39;form_html&#39;];`.

That seems to me like protection against both page reload and back button problems.

Did I goof by trying to reinvent the wheel?

Simple PHP Post-Redirect-Get code example

I have a single form that, depending on which radio button is clicked (Login or Signup), displays either:

 - email address
 - password

or:

 - name
 - age
 - email address
 - password

Clicking on the radio button toggles the visibility of the Login/Signup fields:

    &lt;form id=&quot;myForm&quot;&gt;
        &lt;input name=&quot;userAction&quot; type=&quot;radio&quot; value=&quot;login&quot; checked=&quot;checked&quot;&gt;Login&lt;/input&gt;
        &lt;br /&gt;
        &lt;input name=&quot;userAction&quot; type=&quot;radio&quot; value=&quot;signup&quot;&gt;Sign Up&lt;/input&gt;
    
        &lt;div id=&quot;loginFields&quot; style=&quot;display:none&quot;&gt;
            &lt;!-- Login fields (email address and password) --&gt;
        &lt;/div&gt;
        
        &lt;div id=&quot;signupFields&quot; style=&quot;display:none&quot;&gt;
            &lt;!-- Signup fields (name, age, email address, password) --&gt;
        &lt;/div&gt;
    &lt;/form&gt;

I&#39;m using the [jQuery Validation plug-in][1], and I&#39;d like to use the following rules:

    var signupRules = {
        emailAddressTextBox:
        {
            required: true,
            email: true 
        },
        passwordTextBox:
        {
            required: true,
            minlength: 6,
            maxlength: 24,
            passwordValidationRule: true // custom regex added with $.validator.addMethod()
        }
    };
    
    var loginRules = {
        nameTextBox:
        {
            required: true,
            maxlength: 50
        },
        loginEmailAddressTextBox:
        {
            required: true,
            email: true 
        },
        loginPasswordTextBox:
        {
            required: true,
            minlength: 6,
            maxlength: 24,
            passwordValidationRule: true // custom regex added with $.validator.addMethod()
        },
        loginPasswordAgainTextBox:
        {
            required: true,
            minlength: 6,
            maxlength: 24,
            equalTo: &quot;#loginPasswordTextBox&quot;
            passwordValidationRule: true // custom regex added with $.validator.addMethod()        
        }
    };

How can I add the correct validation rule dynamically based on:

       $(&quot;input[name=&#39;userAction&#39;]&quot;).change(function() {
            if ($(&quot;input[name=&#39;userAction&#39;]:checked&quot; ).val() === &quot;login&quot;) {
                // use loginRules
            } else {
                // use signupRules
            }
        });


I&#39;ve tried the following:

    $(&quot;#myForm&quot;).validate({
        rules: ($(&quot;input[name=&#39;userAction&#39;]:checked&quot; ).val() === &quot;login&quot;) ? loginRules : signupRules;
    });
    
But since my Login fields are the default displayed, its validations work, but the Signup scenario doesn&#39;t; it wants to validate Login fields for some reason.  Am I missing something?

  [1]: http://docs.jquery.com/Plugins/validation


jQuery Validation: Changing Rules Dynamically

I am wondering if the HTML5 `&lt;video&gt;` tag now supports playback of .avi format video files.

Does HTML5 &lt;video&gt; playback support the .avi format?

<p>I am wondering if the HTML5 <code>&#x3C;video></code> tag now supports playback of .avi format video files.</p>


I&#39;ve been trying to write a video+audio using AVAssetWriter and AVAssetWriterInputs.
 
I read multiple posts in this forum of people saying they were able to accomplish that, but it is not working for me.
If I just write video then the code is doing its job very well. When I add audio the output file is corrupted and cannot be reproduced.
 
Here is part of my code:
 
Setting up AVCaptureVideoDataOutput and AVCaptureAudioDataOutput:

    NSError *error = nil;

    // Setup the video input
    AVCaptureDevice *videoDevice = [AVCaptureDevice defaultDeviceWithMediaType: AVMediaTypeVideo];
    // Create a device input with the device and add it to the session.
    AVCaptureDeviceInput *videoInput = [AVCaptureDeviceInput deviceInputWithDevice:videoDevice error:&amp;error];
    // Setup the video output
    _videoOutput = [[AVCaptureVideoDataOutput alloc] init];
    _videoOutput.alwaysDiscardsLateVideoFrames = NO;
    _videoOutput.videoSettings =
    [NSDictionary dictionaryWithObject:
    [NSNumber numberWithInt:kCVPixelFormatType_32BGRA] forKey:(id)kCVPixelBufferPixelFormatTypeKey];     

    // Setup the audio input
    AVCaptureDevice *audioDevice     = [AVCaptureDevice defaultDeviceWithMediaType: AVMediaTypeAudio];
    AVCaptureDeviceInput *audioInput = [AVCaptureDeviceInput deviceInputWithDevice:audioDevice error:&amp;error ];     
    // Setup the audio output
    _audioOutput = [[AVCaptureAudioDataOutput alloc] init];

    // Create the session
    _capSession = [[AVCaptureSession alloc] init];
    [_capSession addInput:videoInput];
    [_capSession addInput:audioInput];
    [_capSession addOutput:_videoOutput];
    [_capSession addOutput:_audioOutput];

    _capSession.sessionPreset = AVCaptureSessionPresetLow;     

    // Setup the queue
    dispatch_queue_t queue = dispatch_queue_create(&quot;MyQueue&quot;, NULL);
    [_videoOutput setSampleBufferDelegate:self queue:queue];
    [_audioOutput setSampleBufferDelegate:self queue:queue];
    dispatch_release(queue);

Setting up AVAssetWriter and associating both audio and video AVAssetWriterInputs to it:

    - (BOOL)setupWriter {
        NSError *error = nil;
        _videoWriter = [[AVAssetWriter alloc] initWithURL:videoURL 
                                                 fileType:AVFileTypeQuickTimeMovie
                                                    error:&amp;error];
        NSParameterAssert(_videoWriter);


        // Add video input
        NSDictionary *videoCompressionProps = [NSDictionary dictionaryWithObjectsAndKeys:
                                                     [NSNumber numberWithDouble:128.0*1024.0], AVVideoAverageBitRateKey,
                                                            nil ];

        NSDictionary *videoSettings = [NSDictionary dictionaryWithObjectsAndKeys:
                                                  AVVideoCodecH264, AVVideoCodecKey,
                                                  [NSNumber numberWithInt:192], AVVideoWidthKey,
                                                  [NSNumber numberWithInt:144], AVVideoHeightKey,
                                                  videoCompressionProps, AVVideoCompressionPropertiesKey,
                                                  nil];

        _videoWriterInput = [[AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeVideo
                                                                outputSettings:videoSettings] retain];

            
        NSParameterAssert(_videoWriterInput);
        _videoWriterInput.expectsMediaDataInRealTime = YES;


        // Add the audio input
        AudioChannelLayout acl;
        bzero( &amp;acl, sizeof(acl));
        acl.mChannelLayoutTag = kAudioChannelLayoutTag_Mono;

            
        NSDictionary* audioOutputSettings = nil;          
        // Both type of audio inputs causes output video file to be corrupted.
        if (NO) {
            // should work from iphone 3GS on and from ipod 3rd generation
            audioOutputSettings = [NSDictionary dictionaryWithObjectsAndKeys:
                                  [ NSNumber numberWithInt: kAudioFormatMPEG4AAC ], AVFormatIDKey,
                                         [ NSNumber numberWithInt: 1 ], AVNumberOfChannelsKey,
                                  [ NSNumber numberWithFloat: 44100.0 ], AVSampleRateKey,
                                  [ NSNumber numberWithInt: 64000 ], AVEncoderBitRateKey,
                                  [ NSData dataWithBytes: &amp;acl length: sizeof( acl ) ], AVChannelLayoutKey,
                                  nil];
        } else {
            // should work on any device requires more space
            audioOutputSettings = [ NSDictionary dictionaryWithObjectsAndKeys:                       
                                  [ NSNumber numberWithInt: kAudioFormatAppleLossless ], AVFormatIDKey,
                                        [ NSNumber numberWithInt: 16 ], AVEncoderBitDepthHintKey,
                                  [ NSNumber numberWithFloat: 44100.0 ], AVSampleRateKey,
                                  [ NSNumber numberWithInt: 1 ], AVNumberOfChannelsKey,                                      
                                  [ NSData dataWithBytes: &amp;acl length: sizeof( acl ) ], AVChannelLayoutKey,
                                     nil ];
        } 
            
        _audioWriterInput = [[AVAssetWriterInput 
                                assetWriterInputWithMediaType: AVMediaTypeAudio 
                      outputSettings: audioOutputSettings ] retain];

        _audioWriterInput.expectsMediaDataInRealTime = YES;

        // add input
        [_videoWriter addInput:_videoWriterInput];
        [_videoWriter addInput:_audioWriterInput];

        return YES;
    }


here are functions to start/stop video recording

    - (void)startVideoRecording
    {
        if (!_isRecording) {
            NSLog(@&quot;start video recording...&quot;);
            if (![self setupWriter]) {
                 return;
            }
            _isRecording = YES;
        }
    }

    - (void)stopVideoRecording
    {
        if (_isRecording) {
            _isRecording = NO;

            [_videoWriterInput markAsFinished];
            [_videoWriter endSessionAtSourceTime:lastSampleTime];

            [_videoWriter finishWriting];

            NSLog(@&quot;video recording stopped&quot;);
        }
    }

And finally the CaptureOutput code

    - (void)captureOutput:(AVCaptureOutput *)captureOutput
    didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer
           fromConnection:(AVCaptureConnection *)connection
    {
        if (!CMSampleBufferDataIsReady(sampleBuffer)) {
            NSLog( @&quot;sample buffer is not ready. Skipping sample&quot; );
            return;
        }


        if (_isRecording == YES) {
            lastSampleTime = CMSampleBufferGetPresentationTimeStamp(sampleBuffer);
            if (_videoWriter.status != AVAssetWriterStatusWriting ) {
                [_videoWriter startWriting];
                [_videoWriter startSessionAtSourceTime:lastSampleTime];
            }

            if (captureOutput == _videoOutput) {
                [self newVideoSample:sampleBuffer];
            }

            /*
            // If I add audio to the video, then the output file gets corrupted and it cannot be reproduced
            } else {
                [self newAudioSample:sampleBuffer];
            }
        */
        }
    }

    - (void)newVideoSample:(CMSampleBufferRef)sampleBuffer
    {     
        if (_isRecording) {
            if (_videoWriter.status &gt; AVAssetWriterStatusWriting) {
                 NSLog(@&quot;Warning: writer status is %d&quot;, _videoWriter.status);
                 if (_videoWriter.status == AVAssetWriterStatusFailed)
                      NSLog(@&quot;Error: %@&quot;, _videoWriter.error);
                 return;
            }

            if (![_videoWriterInput appendSampleBuffer:sampleBuffer]) {
                 NSLog(@&quot;Unable to write to video input&quot;);
            }
        }
    }



    - (void)newAudioSample:(CMSampleBufferRef)sampleBuffer
    {     
        if (_isRecording) {
            if (_videoWriter.status &gt; AVAssetWriterStatusWriting) {
                 NSLog(@&quot;Warning: writer status is %d&quot;, _videoWriter.status);
                 if (_videoWriter.status == AVAssetWriterStatusFailed)
                      NSLog(@&quot;Error: %@&quot;, _videoWriter.error);
                 return;
            }

            if (![_audioWriterInput appendSampleBuffer:sampleBuffer]) {
                 NSLog(@&quot;Unable to write to audio input&quot;);
            }
        }
    }

I would be very glad if someone could find which is the problem in this code.


This code to write video+audio through AVAssetWriter and AVAssetWriterInputs is not working. Why?

I&#39;m looking for a way to view HTML5 `&lt;video&gt;`, frame-by-frame.

The scenario: Having a video, with an additional button that skips to the next frame when pressed.

What do you think is the best method to do this?

 1. Play the video normally, [Listen to `timeUpdate` event, which on FireFox is called for every frame][1], and then just pause the video. However, the other browsers don&#39;t behave like Firefox.
 2. Change the `currentTime` element manually to +1/24 of a second, where &quot;24&quot; is the frame rate. I have no idea how to aquire the FPS, however.
 3. Any other helpful way you can think of.

----------

## EDIT ##

I have found [this very useful HTML5 &lt;video&gt; test page](http://www.inconduit.com/smpte/), which tracks all browsers&#39; ability to achieve accurate frame-seeking.

  [1]: http://stackoverflow.com/q/3688177/207894

HTML5 frame-by-frame viewing / frame-seeking?

Query to `MediaStore.Video.Media.EXTERNAL_CONTENT_URI` returns only video in `/sdcard/DCIM/100MEDIA`

But I want to get thumbnails for video in my `/sdcard/Android/data/mypackage/files` folder. Is it possible ?

Here is part of my code:

            ContentResolver cr = getContentResolver();
        String[] proj = {
                        BaseColumns._ID
        };
         
        Cursor c = cr.query(MediaStore.Video.Media.EXTERNAL_CONTENT_URI, proj, null, null, null);
        if (c.moveToFirst()) {
        	do
        	{
                int id = c.getInt(0);
                Bitmap b = MediaStore.Video.Thumbnails.getThumbnail(cr, id, MediaStore.Video.Thumbnails.MINI_KIND, null);
                Log.d(&quot;*****My Thumbnail*****&quot;, &quot;onCreate bitmap &quot; + b);
                ImageView iv = (ImageView) findViewById(R.id.img_thumbnail);
                iv.setImageBitmap(b);
        	}
        	while( c.moveToNext() );
        }         
        c.close();


How to get thumbnail for video in my /sdcard/Android/data/mypackage/files folder?

is it possible to display a html5-video as part of the canvas?

basically the same way as you draw an Image in the canvas. 

    context.drawVideo(vid, 0, 0);

thanks!

html5: display video inside canvas

This question might be very basic

Is there a way to reduce the frame size/rate of Lossy compressed (WMV, MPEG) format, to get a smaller video, of lesser size, with same format.

Are there any open source or proprietary apis for this?


Reducing video size with same format and reducing frame size

`&amp;mdash;` or `&amp;#8212;`

Is there a difference between these?  Is one better-supported than the other?

`&amp;mdash;` or `&amp;#8212;` is there any difference in HTML output?

The standard checkboxes rendered in most browsers are quite small and don’t increase in size even when a larger font is used.  What is the best, browser-independent way to display larger checkboxes?

Checkboxes in web pages – how to make them bigger?

What does it mean when an attribute like the hidden attribute is a boolean attribute? Can someone explain this in layman&#39;s terms?

What does it mean in HTML 5 when an attribute is a boolean attribute?

I am trying to style a checkbox using the following:

&lt;!-- begin snippet: js hide: false console: true babel: false --&gt;

&lt;!-- language: lang-html --&gt;

    &lt;input type=&quot;checkbox&quot; style=&quot;border:2px dotted #00f;display:block;background:#ff0000;&quot; /&gt;

&lt;!-- end snippet --&gt;

But the style is not applied. The checkbox still displays its default style. How do I give it the specified style?


How to style a checkbox using CSS

I want to change the thickness of my horizontal rule (`&lt;hr&gt;`)in CSS. I know it can be done in HTML like so - 

    &lt;hr size=&quot;10&quot;&gt;
But I hear that this is [deprecated][1] as mentioned on [MDN here][2]. In CSS I tried using `height:1px` but it does not change the thickness. I want the `&lt;hr&gt;` line to be `0.5px` thick. 

I am using Firefox 3.6.11 on Ubuntu 

  [1]: https://www.w3.org/TR/html401/present/graphics.html#h-15.3
  [2]: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/hr

Content Type	Original Author	Original Content on Stackoverflow
Question	phuang07	View Question on Stackoverflow
Solution 1 - Video	Richard Poole	View Answer on Stackoverflow
Solution 2 - Video	bobince	View Answer on Stackoverflow
Solution 3 - Video	thenengah	View Answer on Stackoverflow
Solution 4 - Video	Jörg W Mittag	View Answer on Stackoverflow

Does HTML5 <video> playback support the .avi format?

Video Problem Overview

Video Solutions

Solution 1 - Video

Solution 2 - Video

Solution 3 - Video

Solution 4 - Video

jQuery Validation: Changing Rules Dynamically

Simple PHP Post-Redirect-Get code example

Attributions