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4F4 File Format Specification

Jul 22, 2010 11:34 AM

Is there a file format specification document available for the 4F4 file format? The HTTP Dynamic Streaming product page has a link titled "Learn about the F4F file format specification" but the link leads to the FLV/F4V file format specification document.

 
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    Jul 22, 2010 1:40 PM   in reply to bradtgmurray1
     
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    Aug 17, 2010 10:43 AM   in reply to bradtgmurray1

    The file format spec provided in one of the replies is the manifest file format specification - F4M.

     

    The actual f4f file format specification is only available under NDA. We have a white paper that we are working on @ Adobe, and once that is out, I can update you. Stay tuned.

     

    Thank you !

     
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    Aug 23, 2010 7:37 AM   in reply to Nikhil Pavan Kalyan

    The F4F format has to be parsed into an FLV before it can be played in flash. You can see how the OSMF is parsing it here.

     

    http://opensource.adobe.com/svn/opensource/osmf/trunk/framework/OSMF/o rg/osmf/net/httpstreaming/f4f/

     

    It may help you figure out how to turn an FLV into an F4F

     
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    Aug 31, 2010 1:12 AM   in reply to Nate Burr

    Of course it can be reverse engineered, but it shouldn't be this hard to put a format specification online which

    is hopefully a finished document already. Why should we disassemble a volkswagen first to know how to

    assemble a porsche. Just supply a spec.

     
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    Dec 3, 2010 12:43 PM   in reply to Nikhil Pavan Kalyan

    Just curious if Adobe's white paper on f4f spec is available yet?

     
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    Dec 3, 2010 1:00 PM   in reply to Petro Gretchanei
     
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    Dec 3, 2010 1:10 PM   in reply to Nate Burr

    looks like that link points to f4V specifications, not f4F.

    I've found this

    http://www.adobe.com/products/httpdynamicstreaming/pdfs/httpdynamicstr eaming_wp_ue.pdf

     

    whitepaper that briefly talks about f4f spec, but I'd like to see Adobe's official white paper on f4f.

     
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    Feb 8, 2011 1:42 AM   in reply to Petro Gretchanei

    Hi !

    Any news about a public version of f4f and f4x specifications ?

    Are the f4f/f4v files used to provide services from live streams ?

     
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    Feb 8, 2011 4:40 PM   in reply to jltresset

    f4f and f4x specs are includded in the document mentioned above : http://download.macromedia.com/f4v/video_file_format_spec_v10_1.pdf  

    f4f is another name for f4v. This doc has all the specs, box order, fields, offsets, etc.

     
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    Nov 3, 2011 4:16 PM   in reply to bradtgmurray1

    I can't see the specs for *F4X* there - the index file?

    Perhaps it's named something non-obvious ...

     

    I'm currently looking at which implementation of HTTP Streaming to employ for our project - Apple's HLS or Adobe's HDS.

    And I must admit, I feel some Anger with Adobe's implementation.

     

    It is overly-complex, uses unreadable data formats, has reinvented the wheel in many areas, has the bare minimum of open-source components

    (e.g. neither the segmenter nor the now-required-thanks-to-convoluted-architecture Apache module have source available),

    and generally has been much more of a *Pain In The **** to get to grips with than Apple's HLS.

     

    Why do index files and boxes even exist, enclosing fragments in sements? (nice hijacking of existing terminology there btw - that's not going to confuse anybody).

    This architecture increases complexity in all areas - in media Creation, Management, and Delivery.

    Most stupidly it means the content delivery server must do nontrivial work when serving content, rather than "just serve files" (as happens with HLS).

    With HLS I can use whatever stupidly simple and fast web server I want (and granted if I want more functionality - which I don't - extend it my damn self).

    With Adobe I have to either buy FMS (we're not going to force you to, just make if f'ing uncomfortable to do anything BUT), use the binary-only Apache module, or get my own custom module done.

    How well is that going to SCALE, where on each fragment request, the delivery server must parse the index, transform the request to byte offsets in the f4v files, then chop these bytes from the f4v files, before finally sending them to the client? Rather than HLS where all it has to do, is do it's usual thing - "just serve a file".

    I suspect it will scale terribly. Perhaps at the most-optimistic - "much less well".

     

    And the f4m and f4x file formats - for things which are basically indexes and metadata, they've invented their own new formats - why is one a binary format, while the other's useful data is base64-encoded-AMF .... (yeah, AMF, also cool, let's reinvent our own messaging format ...) ... let me just open that up in my text editor and debug my problem there ...

     

    I'm sorry but none of this seems like a simple, elegant, open and well-architected solution.

    Actually it seems more like a piece of crap.

    In the interests of open-mindedness I'm still going to persevere with HDS today, but so far it looks more headaches than it's worth. I'm kind of looking forward to deleting all evidence of it from my systems.

    Nick

     
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