March 6th, 2006, 10:20 PM | #16 |
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No, I'm talking about one file with a variable bit rate because that's one of the advantages of it, one file that can self adjust to different connection speeds instead of 2 or 3 seperate files all with their own constant bit rates. My encoder has the option to encode a single file as a VBR. I always thought any player could do it but a special server like a true streaming server may be needed to adjust the file. I don't know because I've never encoded a VBR because I want broadband users to get the best quality at a constant data rate and dial up will have their own dedicated file however crappy it is which is what they would see anyway with a VBR file because it would adjust down to their connection speed.
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March 7th, 2006, 09:55 AM | #17 |
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I believe multibitrate Windows Media and RealMedia files require their respective streaming servers which measure the connection speed to a client and then feed the correct speed. On the other hand, multibitrate QuickTime files don't, as the QuickTime player installed on the client machine can choose which stream to play.
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March 7th, 2006, 03:26 PM | #18 |
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I am going to encode a VBR file and see how it performs from my standard webserver with a high speed connection and a dial up connection. I know I should be able to view it with a high speed connection no matter what and if it does scale the bitrate as it should I should also be able to view it on a dial up connection too without having to wait a few days.
Another cool thing that can be done with a true streaming server is indexing Windows Media files. Once you have encoded a file, you can open it in an indexing tool and do anything from making webpages open at an exact point in a video and/or make another audio/video automatically open and begin to play. So, you could actually daisychain a/v files to play indefinitely. Making a web page open during a video presentation would be useful to reference what was being discussed at that exact moment in the video. This is done with a timeline where you set points for it to occur. I was able to use the indexing feature but only on my local machine and not on my standard web server. It's still a cool tool. |
March 7th, 2006, 06:48 PM | #19 |
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that won't work, james, because vbr files contain only one video stream.
you have to do it like chris outlined, and specify that it's a multi-bitrate file that contains whatever seperate video streams you specify the bitrate for. go ahead and create your vbr file, then compare it's overall total size with the cbr file you created(same source file, of course)... the vbr file size will be smaller, but the picture quality should be identical, if you used 1-pass encoding on both of 'em. vbr is better for broadband because the overall file size is smaller, so it downloads quicker. |
March 10th, 2006, 08:42 PM | #20 |
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VBR vs Multistream
Just want to confirm that VBR is not the method of having multiple bit rates for high and low speed connections within a single file. There are multiple methods to support different connection speeds. One method is to let the streaming server determine the connection speed and stream the appropriate file or stream within a single file. Another option is to move this decision to the browser code itself, typically using JavaScript the connection can be determined, and then the HTML code requests the appropriate file from the streaming server.
This method can be expanded on - the JavaScript code can also determine what the default media player is and then request connection to the appropriate streaming server. Example: HTML page loads with JavaScript that determines the connection speed is high speed and the default media player is Windows Media Player - the page then requests the high-speed windows media file from the windows media streaming server. These are methods that make decisions for the viewer versus presenting the viewer with a bunch of questions that they do not understand. |
March 10th, 2006, 09:58 PM | #21 | |
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March 11th, 2006, 11:58 AM | #22 | |
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Here is a link to a program I just finished that uses this browser-side technique. Clicking on the link will launch an initial page, which invokes the player window with what it has determined about your environment. Based on your environment it will launch one of the following: * Page with embedded Windows Media Player with a high-speed stream * Page with embedded Windows Media Player with a lo-speed stream * Page with embedded Real player with a multi-stream (single file with multiple streams) http://www.intellor.com/l/?l=851 Last edited by Richard Rist; March 12th, 2006 at 09:18 AM. |
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March 11th, 2006, 04:59 PM | #23 |
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nice post richard! couple of questions...
why use the windows media 8 video codec with the newer 9.1 audio codec? i see flash8 being invoked on that page, but it's not used for the buttons... so my real question is, do you know how to wrap the windows media stream underneath a clickable flash layer, using a flash player interface? |
March 11th, 2006, 05:59 PM | #24 | |
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As far Flash, the only flash on this program is the "welcome" in the upper tab. As far as your question of a Flash player or the video under a Flash Layer the answer is yes that would be possible - it is possible to tie elements to the timeline of the video. A small example of this is the small tracking graphic at the bottom of the video window - this small gif and its movement is tied to the time line of the video. |
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March 11th, 2006, 09:26 PM | #25 | |
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March 23rd, 2006, 01:01 PM | #26 |
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Dan, James, Richard, Christopher, etc.,
(my apologies not not letting this thread die...:^) If I understand correctly, it was stated that variable bit rate encoding produces the best trade off between internet quality playback and file size. As a test, I encoded a variable-rate windows media file (wmv) and placed it on my "progressive streaming" net host server. When I "paused" the clip playback, my video disappeared! Playback resumed only with the audio component. Up to this point I have been rendering at a constant bit-rate which acts normally. Has anyone else noticed this? In a somewhat similar vein, has anyone looked into setting up a streaming host using Unreal Streaming Technologies Media Server? Not sure about Linux but it enables a Windows host to stream. Also, it seems to be "open-source" for individuals and small businesses, including an SDK for customizing. |
March 25th, 2006, 03:24 PM | #27 |
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post links for both of the above, so we can check it out.
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March 26th, 2006, 12:04 PM | #28 |
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March 26th, 2006, 10:38 PM | #29 |
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that's very interesting... as a server, it looks like it's maybe only practical for up to 10 concurrent users, because after that you have to step up to something like windows server 2003, which includes the windows media server for free... you can rent windows server 2003 for only a few dollars more a month than a linux server.
i'd be looking for a user group that supported that server, before using it... i didn't see one listed on the site. the realmedia server(helix?) is also offered for free, or very cheap, so it would also be worth looking into. |
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