Talk:Advanced Systems Format

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Some practical clarifications[edit]

Thanks to the authors of this fine article. But as someone looking it up to help me getting some practical things done I was mightily frustrated as I missed just a few crucial PRACTICAL facts. In all fairness: Microsoft contributed a lot to these misunderstandings. To remedy this, I would like to propose a few minor changes, which I submit here first since I am far from a specialist in this field.

Existing: "ASF container-based media are usually streamed on the internet either through the MMS protocol or the RTSP protocol."

Proposal: "ASF container-based media are sometimes still streamed on the internet either through the MMS protocol or the RTSP protocol. Mostly, however, they contain material encoded for 'progressive download', which can be distributed by any webserver and then offers the same advantages as streaming: the file starts playing as soon as a minimum number of bytes is received and the rest of the download continues in the background while one is watching or listening.

Existing: "Files containing only WMA audio can be named using a .WMA extension, and files of audio and video content may have the extension .WMV. Both may use the .ASF extension if desired."

Proposal: "Acording to Microsoft, the ASF file format is now replaced by two others; indeed the current version of Windows Media Encoder produces files with the extension .wma (and MIME-type 'audio/x-ms-wma') and .wmv (MIME-type 'video/x-ms-asf'). These files are identical to the old .asf files but for their extension and MIME-type. According to Microsoft, the change in extensions was made to make it easier for an application to identify the content of a media file (see Q284094). Although this differentiation was introduced in 2003, to this date most webbrowsers (including the latest versions of Internet Explorer and Firefox) do not function as might be expected with the 'new' extensions: even when a .wma or .wmv file is specifically encoded for progressive download, browsers still proceed to completely download the file before playing it. This can, however, be easily remedied by simply renaming the .wma or .wmv file to the old extension .asf." (Yeah, it was that easy; but noone told me... :-)

One more quible: "Note that the file extension abbreviations are different from the codecs which have the same name." I'm not even sure what is meant here; maybe that WMA may refer to a) the whole set of Windows Media technologies; b) a set of audio and video codecs and c) the extensions used for Microsoft's ASF container format. Anyway, whatever is meant here, I think it could be more clearly formulated. Mabelis (talk) 14:47, 10 March 2012 (UTC)

The latter part of your last proposal is based upon a misunderstanding of the issue at hand. In order for "progressive" download to occur the download must be transferred from the browser itself starting the download to the secondary application. This was easy to do via plug-ins, but for straight hyperlinks the indirection method (via linking to an ASX to indirect to the ASF, WAX for WMA, and WVX for WMV) is recommended. When the indirection method is not used then the provider would only be able to take advantage of systems where the browser will hand off the media URLs to the appropriate application. I believe this is limited to Internet Explorer (via IPersistMoniker) and requires the providing web server to have the correct MIME types set up. I am unaware of equivalent support in other browsers, but my lack of positive knowledge is not to be interpreted as proof of lack of support elsewhere: that would take research for validation/verification. I suspect in your usage the web server did not have the appropriate MIME types set up to serve the file types in question. Progressive playback will also be blocked if there is contention for MIME type associations on the system (as in Windows Media Player has the MIME-to-CLSID association but AppX has the local file association - or vice versa), but that's a secondary consideration: the first key is the server-side MIME type associativity. Preppy (talk) 04:51, 13 September 2013 (UTC)

Unix-like[edit]

Does ASF support exist in any software for GNU/Linux, *BSD, and Unix? —Preceding unsigned comment added by 69.212.100.83 (talk) 2004-11-18T04:30:48

Yes, via ffmpeg's libavformat or other demuxers in the VLC Media Player, MPlayer, and similar. ffmpeg also supports many of the codecs usually encapsulated within ASF, including older WMA and WMV codecs, as well as MS-MPEG4. --Kiand 19:18, 25 December 2005 (UTC)

re:[edit]

mplayer can work with asf files.—Preceding unsigned comment added by 151.203.150.87 (talk) 2004-11-25T05:33:58

ASF is not Advanced Streaming Format[edit]

See Microsoft's site—Preceding unsigned comment added by 83.57.45.164 (talk) 2006-02-03T21:20:09

It used to be called Advanced Streaming Format. Ive moved the page to the current name now. Thanks. -- jeffthejiff 18:47, 3 February 2006 (UTC)
very apt, thanks --vineeth 06:04, 4 February 2006 (UTC)

Clarification on "structure" needed[edit]

This sentence needs clarification:

The format does not specify how (i.e. with which codec) the video or audio should be encoded; it just specifies the structure of the video/audio stream.

What aspects of the structure are defined by asf? x bytes of video, y bytes of sound? Number of subtitle streams? Frame types (e.g. sequence p fames and b frames or whatever)? --Slashme 07:52, 16 January 2007 (UTC)

The most common filetypes contained within an ASF file are Windows Media Audio (WMA) and Windows Media Video (WMV). Note that the file extension abbreviations are similar in name to the codecs of the same name but are different things. Does the word filetype in this sentence mean that the container doesn't contain WM*-encoded streams but entire "files", i.e. subcontainers which in turn contain streams? I'm confused.--87.162.63.109 22:14, 24 August 2007 (UTC)

Wget PRO, asfrecorder[edit]

These are (or were) tools to download mms:// streams; should they be mentioned in the article? sendmoreinfo (talk) 10:13, 26 January 2008 (UTC)

Italic text —Preceding unsigned comment added by 184.40.31.238 (talk) 16:58, 29 January 2011 (UTC)

History is incomplete[edit]

In which year the ASF container was invented, or released? Certainly when the "Active-Mania" was born (Active Movie, Active Desktop, ActiveX, Active Setup, Active Streaming Format, etc etc etc). 189.121.196.155 (talk) 06:28, 15 August 2011 (UTC)

Restore fullscreen on ps3[edit]

Not able to restore fullscreen on ps3. When YouTube UPDATED there PLATFORM 2-4 months ago it UPDATED to fullscreen than someone ACCIDENTALLY signed me out of YouTube and it wouldn't let me sign bk in. What can I do. Jackshaft1953 (talk) 10:33, 20 July 2018 (UTC)