iPhone video streaming
Jun/110
Mobile devices have changed the way people look at the web recently. Now the web is more personal than ever and more mobile than ever expected before. Video has also transformed the web … and recently these two movements collided!
I’ll talk briefly about the main problems that needed to be solved to get video to mobile phones. Read on…
Google’s(On2) VP8 and the video future
May/100
Google has made “public” and “open-source”, “patent-free” and “royalty-free” their recently acquired with the purchase of On2 video codec VP8. It’s an amazing step for the world of digital video. This step obviously was coordinated with other companies like Adobe, which ensured support for the new codec in further versions of Flash and Sorenson that presented an encoder ready to work with the new codec. They have also provided patches for the hugely popular transcoding programs ffmpeg and mencoder that
This is big news and consequences for web video may be really profound. It’s an amazing amount of events for a single month and they did in in a single day. Well done Google!
HD compromises – “near HD” – “HD Lite”
Aug/091
High definition video imposes huge requirements on bandwidth for the video data stream. The requirements are so high that many enthusiasts consider the bandwidth in the BluRay(40mbps) and HD-DVD(28mbps) to be inadequate to get a “decent fidelity” HD video playback. Well this is formally true … in some cases. In practice we’ve lived with the low standard definition(SD) content for more than two generations now. If the technology still struggles with single consumer solutions, what do we do with HD video on the web then? Besides the raw bandwidth there are other solutions improving the odds in our favor a bit.
HD web video
Jul/096
High definition video or HD video as it is known, is digital video with higher resolution than the previous standards (i.e. SD video and DVD). This high resolution is achieved through new video file formats, which allow new codecs, certain performance optimizations (like deblocking) and a lot higher bandwidth(bitrate).
HD resolutions are noted with the number of lines and if it is progressive or interlaced stream. Thus 540p for instance means – resolution 960 x 540 pixels (assuming 16:9 aspect ratio) and progressive stream. Note that interlaced streams are primarily available for compliance with older standards like DVD.
Progressive download – streaming?
Jul/090
Http streaming or as it is better known – progressive download, which has been developed as a marketing term by Macromedia as the “poor man’s streaming solution” for their Flash platform. Progressive download is available from Flash 7 onwards and in essence means a “play-as-you-download” method, that works with standard http web servers. The concept is not invented by Macromedia though, as it has existed for some time with the development of streamable file formats.
Progressive download streaming is achieved by downloading a file “progressively” i.e. from the start onwards up to the end and playing it. FlashVideo(FLV) is a streamable file format as the packets of video data are defined in a “row”(or queue) and can be interpreted one by one, without a need to read all the packets to the end first. As a result progressive streaming provides a similar experience to true media server streaming, but without the need of a media server.
Flash Video
Jul/091
FlashVideo(FLV) is the video format that Macromedia created for their FlashPlayer rich media browser plugin. Due to the fact that FlashPlayer plugin (now owned by Adobe) has a web presence in excess of 97%. It is safe to say that about every computer that connects to the internet can play video in FlashVideo format.
The file format of .FLV files is by design based on the h.263 standard. The newer FlashPlayer(9.0.0.29 or above) supports h.264/mp4 files which may have extension .flv(.f4v).
Web Video File Formats
Jul/091
File formats containing video are called video formats. These file formats now in the time of web video are usually container formats. A container format is essentially a sequence of packets containing data like video frames and audio samples. This sequence of packets can be regarded as a stream, thus many of the modern container file formats can be used for streaming video. Besides the streamable packet structure these container formats provide another great benefit – codec abstraction. A codec (‘coder-decoder’) is a algorithm that allows video information to be stored digitally in a more efficient manner. With this codec abstraction container formats are capable of “outliving” the initial codec they were intended to work with and achieve better results(in video quality/storage) while maintaining a good level of compatibility over time. Some formats have been created around a single codec instead of supporting multiple ones, however that approach is considered outdated in the web video era.
Streaming Cost Calculator
Jul/094
Streaming costs is a complex calculation and differ for each service provider, depending on their business model. However there are common factors that are taken into account in all cases and you should be aware of these in case you intend to publish video online.
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