List of Flash codecs supported by GravityLab video hosting

June 15th, 2010

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.

Streaming video to iPhone FAQ

June 6th, 2010

Streaming video to iPhone Frequently Asked Questions

  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

What you need to know about iPhone HTTP streaming

January 11th, 2010

One of the drawbacks of many kinds of streaming media is that there are special protocols and non-standard ports used, which can lead to several different types of failures, and ultimately, a lot of frustration. When Apple set out to include a streaming video feature on their iPhone OS, they decided to use HTTP for several reasons. First and foremost, they could avoid many of the pitfalls of typical streaming media setups. For example: RTSP streams are often rejected by overzealous firewalls and routers, which means that many viewers who reside behind corporate/office firewalls will not be able to view your video stream.

How to simulate a live broadcast with Windows Media Server

November 25th, 2009

  1. Create Windows Media content and place it in the ASFROOT folder on the Windows Media Services server.
  2. Open the Windows Media Administrator.
  3. From the left side of the Administrator, select Unicast Publishing Points.
  4. In the Broadcast Unicast Publishing Points section, clear the use wizard option. Click Broadcast, and then choose New.
  5. For alias name, type a descriptive name.
  6. For the path type, choose Remote Windows Media Station, and for the URL use msbd://localhost/alias (where alias is the same name you used in the previous step). This provides the connection point for Windows Media Player clients.
  7. Next, on the left side of the administrator, choose Multicast Stations.
  8. Click Stations, and then choose New.

Encoding mobile streaming video and audio for Blackberry

September 29th, 2009

  • BlackBerry® Pearl™ 8100 Series
  • BlackBerry® Curve™ 8300 Series
  • BlackBerry® 8800 Series
  • BlackBerry® Bold™ 9000

Optimal settings for the BlackBerry Pearl 8100

Video settings Audio settings
Video format: MPEG-4
Video file extension: .avi
Resolution (4:3): 240×180
Resolution (16:9): 240×135
Video bitrate: 400 Kbps
Frames per second: 24
Audio format: MP3
Audio bitrate: 128 Kbps
Sample rate: 44 kHz
Channels: 2 (Stereo)

Optimal settings for the BlackBerry 8800/8300/9000

Video settings Audio settings
Video format: MPEG-4
Video file extension: .avi
Resolution (4:3): 240×180
Resolution (16:9): 320×180
Video bitrate: 400 Kbps
Frames per second: 24
Audio format: MP3
Audio bitrate: 128 Kbps
Sample rate: 44 kHz
Channels: 2 (Stereo)

How to convert videos from the Flip camcorder to FLV

July 3rd, 2009

One of the great things about the Flip camcorder is that it saves video using the H.264 Codec. If you haven’t heard, H.264 is arguably the best quality video codec out there, renowned for its high quality, low file size, and lack of artifacting. Luckily, since the release of Flash 9, H.264 is now a web standard. So, if you want to convert your flip MP4 videos to FLV files (from their native mp4 format), all you have to do is rename from “filename.mp4″ to “filename.flv”, and the video should play back with any video player.

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.

What is HTTP streaming?

June 22nd, 2009

HTTP Streaming can be several things. Here is an attempt to outline the different HTTP streaming protocols:

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.

Flash broadcasting not working for some clients

June 10th, 2009

If you are broadcasting live flash video with Wowza streaming server, occasionally a client may receive an error along the lines of “Stream not found”. The reason for this problem is typically that port 1935 is not open on their firewall, which is essential for viewing RTMP (real-time messaging protocol) streams. Alternatively, if you are running Wowza on your own server, you can configure it to stream through port 80 using RTMPT, which is an extension of HTTP. See the pricing of our Live Flash hosting plans for professional flash video broadcasting.

Adding an MP3 playlist to your site

May 11th, 2009

Many times, you may want to have a listener stream MP3s from your site, but you don’t have any streaming software set up. One solution is to create an M3U file which acts as a playlist that opens up with many mainstream MP3 players such as iTunes and Winamp. Following is an example of an M3U playlist:

#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>

How to create a streaming MP3 playlist

April 1st, 2009

M3U files are simply text files with a .m3u extension instead of a .txt extension. When opened in a browser from clicking on a link to an m3u file, the listener’s default audio program will launch the playlist. Many mp3 players support the m3u format, including Winamp and iTunes.

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)