The following table lists the supported codecs and their earliest required SWF file format and Adobe Flash Player versions. Our video hosting accounts also support a huge list of Windows Media, Quicktime, Real Media, mp4, mp3, 3gp, 3gp2 and more.

*Flash Player plays files containing H.264 and AAC that are derived from the standard MPEG-4 container format such as F4V, MP4, M4A, MOV, MP4V, 3GP, 3G2.

Flash Player 9(v 9.0.115.0)supports playback of the following subsets of the MPEG-4 standards:

1. What kinds of encoders are supported?

   The protocol specification does not limit the encoder selection. However, the current Apple implementation should interoperate with encoders that produce MPEG-2 Transport Streams containing H.264 video and AAC audio (HE-AAC or AAC-LC). Encoders that are capable of broadcasting the output stream over UDP should also be compatible with the current implementation of the Apple provided segmenter software.

   Apple has tested the current implementation with the following commercial encoders:

   • Inlet Technologies Spinnaker 7000
   • Envivio 4Caster C4
2. What are the specifics of the video and audio formats supported?

   Although the protocol specification does not limit the video and audio formats, the current Apple implementation supports the following formats:

   • Video: H.264 Baseline Level 3.0
   • Audio:
     • HE-AAC or AAC-LC up to 48 kHz, stereo audio
     • MP3 (MPEG-1 Audio Layer 3) 8 kHz to 48 kHz, stereo audio
     Note: iPad, iPhone 3G, and iPod touch (2nd generation and later) support H.264 Baseline 3.1. If your app runs on older versions of iPhone or iPod touch, however, you should use H.264 Baseline 3.0 for compatibility.
3. What duration should media files be?

   The main point to consider is that shorter segments result in more frequent refreshes of the index file, which might create unnecessary network overhead for the client. Longer segments will extend the inherent latency of the broadcast and initial startup time. A duration of 10 seconds of media per file seems to strike a reasonable balance for most broadcast content.

4. How many files should be in listed in the index file during a continuous, ongoing session?

   The specification requires at least 3 media files be listed in the index file, but the optimum number may be larger. The client identifies an ongoing session by the lack of an #EXT-X-ENDLIST tag in the index file. The client does not allow the user to seek into the last two files in the index for ongoing broadcasts. Periodically, the client requests a new copy of the index.

   The important point to consider when choosing the optimum number is that the number of files available during a live session constrains the client’s behavior when doing play/pause and seeking operations. The longer the list, the longer the client can be paused without losing its place in the broadcast, the further back in the broadcast a new client begins, and the wider the time range within which the client can seek. The trade-off is that a longer index file adds to network overhead—during live broadcasts, the clients are all refreshing the index file regularly, so it does add up, even though the index file is typically small.

   Another point to consider is that clients typically request new copies of the index file at higher rate when the index contains a shorter list of files.

5. What data rates are supported?

   The data rate that a content provider chooses for a stream is most influenced by the target client platform and the expected network topology. The streaming protocol itself places no limitations on the data rates that can be used. The current implementation has been tested using audio-video streams with data rates as low as 100 Kbps and as high as 1.6 Mbps to iPhone. Audio-only streams at 64 Kbps are recommended as alternates for delivery over slow cellular connections.

   Note: If the data rate exceeds the available bandwidth, there is more latency before startup and the client may have to pause to buffer more data periodically. During a broadcast using an index file that provides a moving window into the content, the client will eventually fall behind in such cases, causing one or more segments to be dropped. In the case of VOD, no segments are lost, but inadequate bandwidth does cause slower startup and periodic stalling while data buffers.
6. What is a .ts file?

   A .ts file contains an MPEG-2 Transport Stream. This is a file format that encapsulates a series of encoded media samples—typically audio and video. The file format supports a variety of compression formats, including MP3 audio, AAC audio, H.264 video, and so on. Not all compression formats are currently supported in the Apple HTTP Live Streaming implementation, however. (For a list of currently supported formats, see “Media Encoder.”)

7. What is an .M3U8 file?

   An .M3U8 file is a extensible playlist file format. It is an m3u playlist containing UTF-8 encoded text. The m3u file format is a de facto standard playlist format suitable for carrying lists of media file URLs. This is the format used as the index file for HTTP Live Streaming. For details, see IETF Internet-Draft of the HTTP Live Streaming specification.

8. How does the client software determine when to switch streams?

   The current implementation of the client observes the effective bandwidth while playing a stream. If a higher-quality stream is available and the bandwidth appears sufficient to support it, the client switches to a higher quality. If a lower-quality stream is available and the current bandwidth appears insufficient to support the current stream, the client switches to a lower quality.

   Note: For seamless transitions between alternate streams, the audio portion of the stream should be identical in all versions.
9. Where can I find a copy of the media stream segmenter from Apple?

   The media stream segmenter, file stream segmenter, and other tools are in the /usr/bin/ directory of Mac OS X computers, version 10.6 and later. These tools are frequently updated, so you should download the current version of the HTTP Live Streaming Tools from the Apple Developer website. See “Download the Tools” for details.

10. What settings are recommended for a typical HTTP stream, with alternates, for use with the media segmenter from Apple?

    Your encoder should produce MPEG-2 transport stream (.ts) files with the following characteristics for the Apple segmenter:

    • H.264 Baseline 3.0 video
    • Keyframes every 3 seconds
    • HE-AAC (version 1) stereo audio at 44.1 kHz
    • Four streams:
      • Cellular Fallback—Audio only or audio with still image, 64 Kbps
      • Low—96 Kbps video, 64 Kbps audio
      • Medium—256 Kbps video, 64 Kbps audio
      • High—800 Kbps video, 64 Kbps audio

    These settings are the current recommendations. There are also certain requirements. The current mediastreamsegmenter tool works only with MPEG-2 Transport Streams as defined in ISO/IEC 13818. The transport stream must contain H.264 (MPEG-4, part 10) video and AAC or MPEG audio. If AAC audio is used, it must have ADTS headers. H.264 video access units must use Access Unit Delimiter NALs, and must be in unique PES packets.

    The segmenter also has a number of user-configurable settings. You can obtain a list of the command line arguments and their meanings by typing man mediastreamsegmenter from the Terminal application. A target duration (length of the media segments) of 10 seconds is recommended, and is the default if no target duration is specified.

11. How can I specify what codecs or H.264 profile are required to play back my stream?

    Use the CODECS attribute of the EXT-X-STREAM-INF tag. When this attribute is present, it must include all codecs and profiles required to play back the stream. The following values are currently recognized:

    AAC-LC	“mp4a.40.2″
    HE-AAC	“mp4a.40.5″
    MP3	“mp4a.40.34″
    H.264 Baseline Profile level 3.0	“avc1.42001e” or “avc1.66.30” Note: Use “avc1.66.30” for compatibility with iPhone OS versions 3.0 to 3.12.
    H.264 Main Profile level 3.0	“avc1.4d001e” or “avc1.77.30” Note: Use “avc1.77.30” for compatibility with iPhone OS versions 3.0 to 3.12.

    The attribute value must be in quotes. If multiple values are specified, one set of quotes is used to contain all values, and the values are separated by commas. An example follows.

    #EXTM3U

    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=500000

    mid_video_index.m38u

    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=800000

    wifi_video_index.m38u

    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=3000000, CODECS="avc1.4d001e, mp4a.40.5"

    h264main_heaac_index.m38u

    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=64000, CODECS="mp4a.40.5"

    aacaudio_index.m38u

12. How can I create an audio-only stream from audio/video input?

    Add the -audio-only argument when invoking the stream or files segmenter.

13. How can I add a still image to an audio-only stream?

    Use the -meta-file argument when invoking the stream or file segmenter with -meta-type=picture to add an image to every segment. For example, this would add an image named poster.jpg to every segment of an audio stream created from the file track01.mp3:

    mediafilesegmenter -f /Dir/outputFile -a --meta-file=poster.jpg --meta-type=picture track01.mp3

    Remember that the image is typically resent every ten seconds, so it’s best to keep the file size small.

14. How can I specify an audio-only alternate to an audio-video stream?

    Use the CODECS and BANDWIDTH attributes of the EXT-X-STREAM-INF tag together.

    The BANDWIDTH attribute specifies the bandwidth required for each alternate stream. If the available bandwidth is enough for the audio alternate, but not enough for the lowest video alternate, the client switches to the audio stream.

    If the CODECS attribute is included, it must list all codecs required to play the stream. If only an audio codec is specified, the stream is identified as audio-only. Currently, it is not required to specify that a stream is audio-only, so use of the CODECS attribute is optional.

    The following is an example that specifies video streams at 500 Kbps for fast connections, 150 Kbps for slower connections, and an audio-only stream at 64 Kbps for very slow connections. All the streams should use the same 64 Kbps audio to allow transitions between streams without an audible disturbance.

    #EXTM3U

    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=500000

    mid_video_index.m38u

    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=150000

    3g_video_index.m38u

    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=64000, CODECS="mp4a.40.5"

    aacaudio_index.m38u

15. What are the hardware requirements or recommendations for servers?

    See question #1 for encoder hardware recommendations.

    The Apple stream segmenter is capable of running on any Intel-based Mac. We recommend using a Mac with two Ethernet network interfaces, such as a Mac Pro or an XServe. One network interface can be used to obtain the encoded stream from the local network, while the second network interface can provide access to a wider network.

16. Does the Apple implementation of HTTP Live Streaming support DRM?

    No. However, media can be encrypted and key access can be limited using HTTPS authentication.

17. What client platforms are supported?

    iPhone, iPad, and iPod touch (requires iPhone OS version 3.0 or later) or any device with QuickTime X or later installed.

18. Is the protocol specification available?

    Yes. The protocol specification is an IETF Internet-Draft, at http://tools.ietf.org/html/draft-pantos-http-live-streaming.

19. Does the client cache content?

    The index file can contain an instruction to the client that content should not be cached. Otherwise, the client may cache data for performance optimization when seeking within the media.

20. Is this a real-time delivery system?

    No. It has inherent latency corresponding to the size and duration of the media files containing stream segments. At least one segment must fully download before it can be viewed by the client, and two may be required to ensure seamless transitions between segments. In addition, the encoder and segmenter must create a file from the input; the duration of this file is the minimum latency before media is available for download. Typical latency with recommended settings is in the neighborhood of 30 seconds.

21. What is the latency?

    Approximately 30 seconds, with recommended settings. See question #15.

22. Do I need to use a hardware encoder?

    No. Using the protocol specification, it is possible to implement a software encoder.

23. What advantages does this approach have over RTP/RTSP?

    HTTP is less likely to be disallowed by routers, NAT, or firewall settings. No ports need to be opened that are commonly closed by default. Content is therefore more likely to get through to the client in more locations and without special settings. HTTP is also supported by more content-distribution networks, which can affect cost in large distribution models. In general, more available hardware and software works unmodified and as intended with HTTP than with RTP/RTSP. Expertise in customizing HTTP content delivery using tools such as PHP is also more widespread.

    Also, HTTP Live Streaming is supported in Safari and the media player framework on iPhone OS. RTSP streaming is not supported.

24. Why is my stream’s overall bit rate higher than the sum of the audio and video bitrates?

    MPEG-2 transport streams can include substantial overhead. They utilize fixed packet sizes that are padded when the packet contents are smaller than the default packet size. Encoder and multiplexer implementations vary in their efficiency at packing media data into these fixed packet sizes. The amount of padding can vary with frame rate, sample rate, and resolution.

25. How can I reduce the overhead and bring the bit rate down?

    Using a more efficient encoder can reduce the amount of overhead, as can tuning the encoder settings. Also, the -optimize argument can be passed to the Apple mediastreamsegmenter. This removes some unnecessary padding and can significantly reduce the overhead, particularly for low-bandwidth streams.

26. Do all media files have to be part of the same MPEG-2 Transport Stream?

    No. You can mix media files from different transport streams, as long as they are separated by EXT-X-DISCONTINUITY tags. See the protocol specification for more detail. For best results, however, all video media files should have the same height and width dimensions in pixels.

Hypertext transfer protocol, also known as HTTP, is universally supported, and is much more effective at bypassing firewalls and routers that may otherwise deny traffic that use MMS or RTSP protocols. Why is this? Because almost all internet traffic uses the HTTP protocol, so if a router or firewall rejected HTTP traffic, they would be blocking out most of the internet.

The shining benefit of HTTP streaming is that it allows content distributors to avoid the costly implementation of traditional streaming media servers, which is a huge benefit to small companies just getting started in streaming video. Although it works in a completely different way than RTSP, the effect is still the same. With on-demand video (as opposed to live video), the user can skip forward before the video is finished downloading, much like other types of on-demand streaming. And with live video, the viewer cannot skip forward at all, which reproduces the experience of watching a live broadcast on TV.

So, how do content producers utilize this technology? One option is to purchase a monthly iPhone & mobile streaming video hosting package with GravityLab Multimedia, which makes it easy to get up and running with HTTP streaming.

How our iPhone streaming video hosting works

1. You purchase an account
2. We send you a welcome e-mail with instructions on how to upload your files with any FTP program, and how to start a live broadcast

On-demand streaming:

1. You upload a video file, and it is available for viewing instantly
2. You link to the video via your your web site
   e.g. http://arecibo.gravlab.com:1935/iphone/mp4:your_account/your_video.mp4/playlist.m3u8

Live broadcasting on iPhone 3.0 and later:

1. You Download Quicktime Broadcaster, a free program for broadcasting video from any computer with OS X.
2. You configure the broadcaster according to your welcome e-mail, and then press the Broadcast button
3. You link viewers to http://arecibo.gravlab.com:1935/iphonelive/your_account.sdp/playlist.m3u8

File requirements

• Container format: .mp4, .m4v, .mov
• Dimensions: 480×320
• Codec: H.264 (Low-Complexity version of the H.264 Baseline Profile OR Baseline Profile up to Level 3.0)
• Audio: AAC-LC audio up to 160 Kbps, 48kHz, stereo audio
• Frame rate: up to 30 fps
• Bit rate: up to 1.5Mbps (200Kbps recommended)

More reading:

Apple’s official HTTP streaming documentation
RTSP/RTP/RTCP Streaming media overview
MMS Streaming media overview

1. Open the Windows Media Administrator.
2. From the left side of the administrator, select Multicast Stations.
3. Select the program that contains the playlist that you want to modify and ensure that the program is stopped.
4. Click Streams, and then choose New.
5. For the name, it is best to use the file name of the file that you want to stream.
6. On the Source/Destination tab, specify a unicast URL for the file that you that want to add. This is typically like ms://localhost/filename.asf.

When you connect with a Windows Media Player client to the broadcast unicast publishing point, use the server name or IP address and the publishing point alias from step 5 in the first part of this section. For example: mms://wms1.microsoft.com/live.

via http://support.microsoft.com/kb/285292

Optimal settings for the BlackBerry Pearl 8100

Optimal settings for the BlackBerry 8800/8300/9000

Also note, this applies to any mp4 video as well. If you want to convert videos from MP4 to FLV, try renaming the file before you mess with transcoding the video to FLV with a third party encoding program.

MP3/AAC/aacPlus HTTP Streaming:
This is usually the SHOUTcast or Icecast ICY protocol, which uses ADTS packetization over TCP. This is NOT compatible with ANY RTSP streaming. This uses an ICY based Streaming Server such as SHOUTcast or Icecast2. This is the part that is MOST confusing: QuickTime/Darwin Streaming Server includes an ICY server module for MP3 streaming only. It is based the old deprecated Icecast1 protocol, and is no longer supported or recommended. Icecast2 is the preferred server here.

HTTP Tunnelling:
This is standards-based RTSP/RTP TCP Interleave (RFC-2326/3550) inside HTTP encapsulation to look like HTTP web server traffic to penetrate difficult firewalls. This method will usually get through content filtered firewalls where HTTP/ICY is filtered. Being standards-based, many different types of audio/video codecs may be used for these streams. Most streaming using this protocol is MPEG-4 based today. This uses an RTSP/RTP Streaming Server, such as QuickTime/Darwin Streaming Server.

HTTP Progressive Download Streaming:
This is nothing more than a file download from a Web Server, and the file plays as it is downloading, hopefully, if there is sufficient bandwidth. The file will also land in the user temporary folder, offering no security to content. This method uses a Web Server.

Hopefully, this clears up some confusion on all of this.

via

#EXTM3U
#EXTINF:199,Radiohead - Creep
http://www.yoursite.com/radiohead-creep.mp3
#EXTINF:217,Pink Floyd - Money
http://www.yoursite.com/pinkfloyd-money.mp3

The .m3u file can be placed on any web server, and linked to a web page with the standard a href tag. For instance, to link to a file named “playlist.m3u” from a web page in the same directory with the file, the link could be:

<a href="playlist.m3u">Play my playlist</a>

Note: For .m3u files to work correctly, your web server must be configured to deliver the correct mime type for .m3u files. To do this with Apache (one of the most common web server applications), you can do one of the following:

1. In apache’s conf/ directory, open the file titled “mime.types” and add the following line: audio/x-mpegurl .m3u, and then you will now have to restart apache
2. In your web site’s root directory, create a file (if it doesn’t already exist) called “.htaccess”, and add the following line: audio/x-mpegurl .m3u

M3U playlists are compatible with all of GravityLab’s Audio Hosting accounts.

Here are the contents of an example M3U file:
#EXTM3U
#EXTINF:210,Song Title
mp3/song_title.mp3
#EXTINF:123,Song Title 2
mp3/song_title2.mp3

For each additional song in the playlist, you must add “#EXTINF:” followed by the length of the song in seconds, and the song title. The next line should be the path to the media. This can either be relative to the location of the mp3 file (e.g. mp3/song_title.mp3) or absolute (e.g. http://www.your-site.com/mp3/song_title.mp3)

PC Users

1. Open up notepad.exe and copy and paste the example m3u code into notepad
2. For your filename, enter “your_playlist_name.m3u”, (replace the example name with your own)
3. Choose File > Save As, and when prompted with “Save as Type”, choose “All Files” to prevent notepad from appending a “.txt” to the end of your playlist name

Mac Users

1. Do not use TextEdit to create m3u files because it will add extra formatting to the file that may prevent the m3u file from working properly. Instead, try using TextMate
2. Follow the same instructions as listed for PC users

WAP sites are generally one file that contains many sub-pages within the master WML page. Each page is defined with a special tag called “<card>”. This is why WML pages are known as “decks”, because they contain multiple cards. Each card can contain text, links, input fields, tasks, images, and more. You can provide navigation from card to card with links that work just like HTML anchors (with a # sign to indicate the id of the card.)

Example WAP code

Here is an example WAP site with two cards, each one containing a link to a different type of 3gp mobile video.

<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN"
"http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<!-- Your site code goes in between the wml tags -->
<card id="card_one" title="Card 1">
<p> <a href="rtsp://streaming-server-address/sample-movie.3gp">3gpp movie </a> </p>
<a href="#card_two">Next Page</a>
</card>
<card id="card_two" title="Card 2">
<p> <a href="rtsp://streaming-server-address/sample-movie.sdp">Live 3gpp stream</a></p>
</card>
</wml>

Images

Though generally not encouraged for mobile sites, you can use images. To place images on your WAP site, you must use the .wbmp format. There are many free converters out there, such as WAP Tiger
For example:

<img  src="http://yoursite.com/logo.wbmp" align="middle" height="100" width="100"/>

Tables (not supported by all phones)

If you wish to use tables, there are a few differences between WML and HTML that you must note: First, the tbody tag does not exist in WML. Second, the attributes of the table tag are “title” (the title of the table), “align” (C=center, L=left and R=right) and “columns” (the number of the columns)

<table align="C" title="label" columns="3">
<tr>
<td>col 1</td>
<td>col 2</td>
<td>col 3</td>
</tr>
</table>

Finishing Up

Once you have uploaded your .wml file to your web server, you can direct mobile users to a URL such as “http://www.yoursite.com/your-wap-site.wml”

1. Download the free JW Player from www.jeroenwijering.com and unzip the file somewhere on your computer
2. Open the newly created directory, you should see several files. Upload the following files to your web server, or to your GravityLab home directory.
   • readme.html
   • swfobject.js
   • player.swf
3. Open readme.html in your favorite HTML or text editor.
4. Find the code that begins with <div id=”container”> and ends with </script>. This is the section of code you’ll need to edit and then copy and paste into your own page.
5. Find this line of code:
   s1.addParam(”flashvars”,”file=video.flv&image=preview.jpg”); and replace it with the following (for FLV files):
   s1.addParam(”flashvars”,”streamer=rtmp://arecibo.gravlab.com/streamingvideo/&file=AccountName/YourFile.flv”);
   OR, if you’re streaming mp4, .mov, or .m4v files, replace that line of code with:
   s1.addParam(”flashvars”,”streamer=rtmp://arecibo.gravlab.com/streamingvideo/&file=mp4:AccountName/YourFile.m4v”);
6. Keep in mind that arecibo.gravlab.com is just one of our servers, and if your files are on a different server, then you will replace arecibo.gravlab.com with servername.gravlab.com. If you need help with this part, contact us and we’ll get you squared away.
7. After you’ve copied and pasted that section of code and customized it to point to our servers, you can save it and view it in your web browser.

Answer: Make sure to use the following format in the URL bar for accessing your GravityLab FTP account:

ftp://username:password@ftp1.gravlab.com

1. RTSP/RTP streams use standard IETF streaming protocols to stream video and audio to clients. The Streaming Server supports QuickTime .mov, MPEG-4 .mp4 and 3G .3gp files for on-demand streaming. In addition, the Streaming Server can reflect live streams and playlists using Session Description Protocol .sdp files. Linking to RTSP/RTP streams is described in the Embedding RTSP/RTP Streams section below
2. MP3 streams used the Shoutcast protocol for streaming mp3 files over http. The Streaming Server supports streaming MP3 playlists from locally stored MP3 files and reflecting live MP3 streams from Shoutcast compatible webcasting software. Linking to MP3 playlists and live MP3 webcasts is described in Linking to mp3 streams below.

Embedding RTSP/RTP Streams

RTSP/RTP streams can be embedded in web pages, or played in QuickTime player. The methods for embedding QuickTime Streams presented below require Apple’s new JavaScript Library which can be downloaded here. After the library is downloaded, place it on your web server (the examples below assume that it is placed in the document root of the web server). The library must be referenced in your web page before it can be used. A good place for to reference the library is immediately after the body tag in your html code. For example:

<body>
<script src="/AC_QuickTime.js" language="JavaScript" type="text/javascript">
</script>
Once you have referenced the library as shown, you can use it to embed QuickTime movies from web or streaming servers. The general format for calling the QuickTime Javascript Library to embed movies is:
<script language="JavaScript" type="text/javascript">
QT_WriteOBJECT('Movie URL','MovieWidth','MovieHeight','ActiveX Version',
'First Attribute Name','First Attribute Value',
'Next Attribute Name','Next Attribute Value',
...repeat attributes as necessary
'Last Attribute Name','Last Attribute Value');
</script>

Specifics of embedding a stream

The Movie URL in the example above should not be the rtsp url to your stream. Instead, the Movie URL should be an http URL to a file on a web server (relative or absolute URLs are OK). This file will be either a poster movie the client clicks on to play the stream, a reference movie to the stream, or a placeholder movie that will be replaced by the stream. These options are described below. The MovieWidth and MovieHeight attributes are measured in pixels. You should add 16 to the height if you want do display the QuickTime playback controller for the movie. ActiveX Version should be left blank. The attribute name value pairs are described in detail on Apple’s site here.

Embedding a stream using a Poster Movie

One way to embed a streaming movie is with a poster movie. The client clicks on the poster movie to start the stream. The poster movie can be a file in any format that QuickTime can open (usually a still image). Poster movies are usually used with the target attribute. Using the target attribute, the movie can play in the same space as the poster movie (target set to ‘myself’) or in QuickTime Player (target set to ‘quicktimeplayer’). The url that plays when the poster movie is clicked is set by the href attribute. The following code is used to create a poster movie that will play the stream in the same space as the poster image (target is set to ‘myself’):

Note: A good format to use for a Poster Movie is a .qtif file. The qtif file format is an image file format that only QuickTime understands, so it is unlikely to be hijacked by other players. In addition, setting the mime type with the ‘type’ attribute to insure the QuickTime plugin will get control. Most image formats can be converted into a qtif files with QuickTime Pro and PictureViewer (Classic Mac OS and Windows) or Preview (Mac OS X). Setting the ‘controller’ attribute to ‘true’ displays only the image without the playback controller. When the user clicks on the picture the controller will be displayed. If you want to keep the controller hidden, the attribute ’saveembedtags’ can be set to ‘true’.

Embedding a stream using a Reference Movie
Another way to embed a streaming movie is with a reference movie. There are a variety of ways to create reference movies, which function like pointers to the actual media. The simplest way to create a reference movie is with QuickTime Pro:

• Open QuickTime Player Pro
• From the File menu select “Open URL…”
• Open the URL to your streaming movie using the rtsp url.
• Save the movie that plays as a Self-Contained movie.
• Put the movie that you saved on your web site.
• Make the reference movie the first attribute you specify in the QT_WriteObject method call.

If you don’t have QuickTime Pro, you can create a simple reference movie with any text editor. Just create a text file with one line in the following format:RTSPtextRTSP:///

Save the file with the .mov extension.

Reference movies can also be used to create “movie alternates.” This sophisticated capability of QuickTime allows you to have a single reference that automatically plays content based on the client’s connection speed, operating system platform, etc. Movie alternates are covered in more detail here.

All reference movies can be embedded by specifying them as the first attribute for the QT_WriteOJECT method. Streaming movies embedded using reference movies are often used with the autoplay attribute set to true. In this case the attribute has been set to false so you can scroll to the movie and press the play button on the controller when you want to view the movie. The following code shows a typical use of a reference movie:

<script language="JavaScript" type="text/javascript">
QT_WriteOBJECT('Merry_Go_Round_Physics.mov','320','256','',
'autoplay','false');
</script>

Embedding a stream using a Placeholder Movie

Sometimes web authors want to embed a movie that plays automatically, but they don’t want to use a reference movie. There are two ways to accomplish this:

1. Use the poster movie technique outlined above, but add the attribute ‘autohref’ with the value ‘true’ to the QT_WriteOJECT method call.
QT_WriteOBJECT('poster.jpg','320','256','', 'href','rtsp://soundscreen.com/Educational/Science/Merry_Go_Round_Physics.mov', 'autohref','true', 'target','myself'); </script> 2. Use the poster movie technique outlined above, but replace the ‘href’ attribute with the attribute ‘qtsrc’ and elminate the ‘target’ attribute. This method ignores the poster movie entirely and loads the url specified by ‘qtsrc’ directly:

Linking to mp3 Streams
Linking to mp3 streams requires a text file with the extension .m3u. This file has the URL to your mp3 stream in it. For instance, if a mp3 playlist named “Blues” was playing from the Streaming Server, and the domain name of the server was stream.mydomain.net, the m3u file would contain the link:

http://stream.mydomain.net:8000/blues

The “:8000″ is the port for streaming mp3 playlists from Darwin Streaming Server. If you enable port 80 streaming the “:8000″ is not required. The .m3u file could be placed on any web server, and linked to a web page with the standard tag. For instance, to link to a file named “blues.m3u” from a web page in the same directory with the file, the link could be:

Play the blues

Note: For .m3u files to work correctly, your web server must be configured to deliver the correct mime type for .m3u files:
audio/x-mpegurl .m3u

Demo source code:

<br /> <object height="320" width="200"><param name="kioskmode" value="true"><param name="src" value="my.mp3"><param name="autoplay" value="false"><param name="controller" value="true"><embed height="50" src="http://dna.gravlab.com/your_audio.mp3" type="video/quicktime" width="200" controller="true" autoplay="false" kioskmode="true"><br /> </object><br />

When converting from a compressed to uncompressed file format (for example, from MP3 to AIFF) you shouldn’t notice any reduction in sound quality. However, when converting between compressed formats (for example MP3 and AAC), you may notice a reduction in the sound quality. For the best results, if you want your music encoded in a different file format, you should import the music again from the original source using the new encoding format.

To convert a song’s file format:

1. Open iTunes Preferences.
   Windows: On the Edit menu, click Preferences.
   Mac: From the iTunes menu, choose Preferences.
2. Click the Advanced button, then click the Importing button at the top of the window.
3. From the Import Using pop-up menu, choose the encoding format that you want to convert the song to, then click OK to save the settings.
4. Select one or more songs in your library, then from the Advanced menu, choose one of the following (The menu item changes to show what’s selected in your Importing preferences):
• Convert Selection to MP3
• Convert Selection to AAC
• Convert Selection to AIFF
• Convert Selection to WAV
• Convert Selection to Apple Lossless

To convert all the songs in a folder or on a disk, hold down the Option key and from the Advanced menu, choose Convert Selection to. All the songs in the folder or on the disk will be converted. Some purchased songs are encoded using a protected AAC format that prevents them from being converted. iTunes Plus purchases are not protected and can be converted.

The song in its original format and the newly converted song appear in your library.
About compression

When you convert a song, some data may be lost due to the way certain formats compress data. For this reason these formats are sometimes called “lossy” formats. The advantage of using a “lossy” format is that the file sizes are much smaller, which means you can store more songs in the same amount of disk space. The disadvantage is that the sound quality may not be as good as the original, uncompressed format. Depending on the song, the speakers or headphones, and the player you use to play the song, you may not be able to tell the difference between a compressed “lossy” song and a song that is not compressed.

Once a song is compressed (meaning some of its data is lost) you cannot retrieve the data by uncompressing it. If you convert a song from a “lossy” format to a uncompressed format, the quality of the song will not improve and the file will only take up more disk space. For example, if you convert a song in MP3 format (a compressed format) to AIFF (an uncompressed format) the song will take up much more space on the hard disk, but it will still sound the same as the compressed file. In order to take advantage of uncompressed formats you should only import songs using these formats.

from apple.com

Progressive Downloading
This is a step up from hyperlinking to your video files. It is a temporary solution to the problems mentioned for downloading. The video file is embedded with code that is unique to each type of video, and as soon as enough of the video is downloaded to watch, the video will begin to play. If the user’s connection is fast enough, they can watch the video as it downloads. The disadvantage here is that the viewer cannot skip forward to any part of the video. This solution does not require any special software or streaming server to work.

True Streaming
This is the best way to deliver video to viewers if you want to allow the viewer to instantly skip to any part of the video or if you want to prevent the viewer from downloading the video file to their computer. True streaming works by delivering bits of video through a streaming server, which sends packets of data in real-time, effectively allowing the end user to view the data as it is arriving. This process is not possible with the HTTP protocol. Instead, RTSP is the protocol of choice for streaming media. It stands for real-time streaming protocol, and it is a method of routing video data to the end user. RTSP provides “VCR-style” control functionality such as pause, fast forward, reverse, and absolute positioning, which cannot be achieved with HTTP.

Which method should I use?
If you are serious about your videos, true streaming is the best option for delivering media to a global audience. With instant-access, built in download prevention, VCR style controls, and affordability, there’s never been a better time to start delivering streaming media to your audience. With GravityLab Multimedia, you can have the best of both worlds. We provide methods to access your streaming media via HTTP and RTSP, allowing you to choose which method is best for you. Check out our streaming video hosting plans
to see which plan best fits your needs.

Quicktime Mov
http://helix.gravlab.com:554/sample_100kbit.mov
http://helix.gravlab.com:554/sample_300kbit.mov

Quicktime Mp4
http://helix.gravlab.com:554/sample_100kbit.mp4
http://helix.gravlab.com:554/sample_300kbit.mp4

Quicktime H.264
http://helix.gravlab.com:554/sample_h264_100kbit.mp4
http://helix.gravlab.com:554/sample_h264_1mbit.mp4

Mobile 3GP
http://helix.gravlab.com:554/sample.3gp
http://helix.gravlab.com:554/sample_50kbit.3gp

Windows Media
http://media.gravlab.com/powered.wmv
http://media.gravlab.com/racecar.wmv