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david Eadenhall
Confused over streaming compression settings
on May 3, 2009 at 11:52:01 pm

Hi there

I have HD footage taken directly from my camcorder and edited in Final Cut. I want to be able to compress this footage (about 10 mins for each separate video) to be streamed on my server via a streaming software.

I have compression programs like Final Cut Pro, Quicktime Pro, Mpeg Streamclip and Adobe CS4 Media Encoder and still cant for the life of me compress a video and make it look good at a reasonable bitrate.

My videos can look OK using a bitrate of about 1200-1400 kbps but anything lower and they look poor and pixelated. When I try to stream these files, they are very jumpy and try to buffer alot. When I ask advice from people, they all say that my bitrate settings are too high and should be about 600-800kbps!!! Surely not. At that bitrate, my videos look horrendous. Please someone tell me what on earth I am doing wrong.

My videos will be 960 x 540 frame size, encoded with H264 into a mp4 file.

Im sure this is such a basic thing for someone, but its eluding me. Please help me figure this.

Thank you

Dan


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Craig Seeman
Re: Confused over streaming compression settings
on May 4, 2009 at 3:24:14 am

[david Eadenhall] "When I ask advice from people, they all say that my bitrate settings are too high and should be about 600-800kbps!!! "

What do they all have in common?
What internet connection speed?
What computer specs?

If they have a download speed of around 3000kbps and have reasonably new computers that can decode H.264 then there shouldn't be a problem but if they're all on older or cheap computers and slow download that's another story.

A good test might be if they can play a YouTube video in HD (NOT HQ) mode.
YouTube HD for example is about 2000kbps.

Superficially your frame size and data rate is reasonable given the above.






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Chris Blair
Re: Confused over streaming compression settings
on May 4, 2009 at 3:47:31 pm

Craig SeemanSuperficially your frame size and data rate is reasonable given the above.

It's reasonable for SOME people with new computers and very fast internet connections.

As an example...we have workstation class computers at our facility, most with at least dual processors and several gigs of RAM...along with a T1 line. Yet if only one person is on the internet, we have a hard time playing YouTube HD files without buffering, pausing and stuttering...regardless of the power of the workstation.

At home I have a pretty standard cable connection and a 4 year old laptop with 512MB RAM...yet I can play YouTube HD video without issue.

There are so many potential issues that affect streaming video that bumping up against the boundaries of it's capabilities in pixel size and data rates means that a large percentage of your audience likely won't be able to reliably play your video.

Forget the fact that they SHOULD be able to play it, the simple fact is that many will not be able to. We've always advised clients that it's better for their video to play at good quality, than it is for it to look pristine but pause and stutter...or not play at all.

Chris Blair
Magnetic Image, Inc.
Evansville, IN
http://www.videomi.com


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Craig Seeman
Re: Confused over streaming compression settings
on May 4, 2009 at 6:03:39 pm

David/Dan needs to define his own market.

In my neck of the woods I rarely see anyone with less than 3000kbps and that's even on heavy trafficked lines. Consumer cable modems are 10,000, 15,000, 30,000 and now 100,000kbps.

My point is you MUST know your target market.

David/Dan has described both his encoding specs and anecdotal response. Those viewing may or may NOT be his target. He has to decide. I'm providing a means so he can make that decision.



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david Eadenhall
Re: Confused over streaming compression settings
on May 4, 2009 at 6:16:43 pm

Hi there Craig

Thank you so much for your response - I am so thankful that you have taken the time to respond and help.

My target audience is quite hard to sum up as it will be made up of so many individuals that will be accessing the videos on our servers from different backgrounds of computers. By that I mean some users will be computer fanatics and some will have basic set ups. I guess that makes things so complicated.

I have seen so many sites that embed these HD videos and they stream so well and smoothly. I just want to find a happy medium that allow as many users successfully watch these videos and be satisfied.

I have since learnt that the bit rate that I encode a video by relates to the minimum requirement that my user must have in his internet connection speed. I was able to get a fairly decent result with bit rates of about 1500kbps upwards but was being told by so many people that my bit rate was way too high and that I should be looking more towards 600-800kbps. Either I am doing something very wrong but I cannot for the life of me get anything even barely acceptable looking at that bit rate. It just looks totally blocky and jerky.

By my tests in compression, I am getting file sizes to be about 10mb per minute. Is that sounding high to you?

Craig, again thank you for all your help and I hope im not taking up too much of your time.

Dan


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Daniel Low
Re: Confused over streaming compression settings
on May 4, 2009 at 9:25:56 pm

David? Dan? I'm confused.

More confusion:

There's streaming and there's progressive download. Many confuse the two.

YouTube is progressive download, sometimes called 'HTTP streaming'

Flash (in 95% of cases) is progressive download.

Therefore, regardless of connection speed, all people see the same video at the same quality only that those on slower connections need to wait longer for the clip to buffer/download before it will play.

If the clip is stuttering, wait until it has downloaded more and then play it back. If it still stutters then your computer is simply not capable of playing it back properly.

@Chris:
"As an example...we have workstation class computers at our facility, most with at least dual processors and several gigs of RAM...along with a T1 line. Yet if only one person is on the internet, we have a hard time playing YouTube HD files without buffering, pausing and stuttering...regardless of the power of the workstation. "

T1 is only 1500kbps, as Craig pointed out, YouTube HD is approx 2000kbps

"At home I have a pretty standard cable connection and a 4 year old laptop with 512MB RAM...yet I can play YouTube HD video without issue. "

Your cable connection is likely to be faster than the T1, even with contention.

For a proper HD experience, regardless of connection speed (but requiring a semi powerful computer at least) this is the ultimate:

HD/a>

Like with youtube, these are progressive download so you can view them even on a 56k connection. You'll just have to wait.

__________________________________________________________________
Two years from now, spam will be solved. - Bill Gates, World Economic Forum 2004


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Chris Blair
Re: Confused over streaming compression settings
on May 5, 2009 at 2:13:52 am

Guys,

We get clients who want to put the highest quality video on their internet sites and aren't satisfied until we output videos compressed between 1000-2000kbs.

The video plays great on new computers with fast connections, but on many, it takes quite a while to buffer before it starts playing, and even then, it will buffer several more times during playback.

What do most site visitors do when this happens? They either don't watch the video or they move on to a new page..or worse..a new website. If David's site is strictly for watching his videos, then by all means, do them at the highest quality you can get away with or that customers will tolerate.

But if it's a typical business website where people go to get information as well as watch video, it's better to make the videos smaller (both in pixel and file size), and make sure they'll play continuously.

The 10MB/minute file size doesn't sound outrageous, but from the clients we work with, it's certainly on the upper end of what's going to play reliably across a wide range of users. We shoot for 6-8MB/minute at a smaller size of 640x360 (depending on the content) or even 512x288 at 5-6MB/minute.

If quality and showing the video at a large size is important, then he'll have to live with the fact that likely half his audience will have buffering issues during playback.

The servers the videos are on also make a difference.

We have one client that uses Limelight for their CDN, which caches video on their servers, (theoretically improving playback), yet we've been unable to get 640x360 video at 10MB/min to play reliably on a large number of connections. The client settled on 512x288 at around 8MB/minute as their default because it plays reliably and still looks very good.

If you're hosting the videos on your web sever, you're not going to get the same performance as you would from hosting them on a Content Delivery Network separate from your website.

And to clarify, my home cable connection tests at about half the speed of our office T1 line. This illustrates that more than just the connection speed impacts playback. Your CPU, RAM, graphic card and its settings, Flash versions, etc. all can impact performance. After the video is delivered, your CPU still has to decompress it and your graphic card still has to process it.

Chris Blair
Magnetic Image, Inc.
Evansville, IN
http://www.videomi.com


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Daniel Low
Re: Confused over streaming compression settings
on May 5, 2009 at 7:40:59 am

[Chris Blair] "then he'll have to live with the fact that likely half his audience will have buffering issues during playback. "

Depending on what format you are delivering, there are ways of calculating the viewers connection speed and tailoring the buffer settings to match there are loads of resources that will explain how to do this, most for Flash, which should be fine for David/Dan



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Two years from now, spam will be solved. - Bill Gates, World Economic Forum 2004


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david Eadenhall
Re: Confused over streaming compression settings
on May 5, 2009 at 12:06:04 pm

Hi there Daniel

Thank you so much for your response. I have chosen to use mp4 format for both streaming and download. I would love to know how its possible to calculate the viewer's connection speed. Can you point me anywhere - this sounds just what i need!

Thank you again

Dan


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Daniel Low
Re: Confused over streaming compression settings
on May 5, 2009 at 2:19:39 pm

If you deliver the download files as Flash (F4V) then you'll find a load of useful information here:

http://www.adobe.com/devnet/flashcom/articles/dyn_buffering.html

or

http://www.betriebsraum.de/blog/2007/02/27/flash-video-tip-1-calculating-an...



__________________________________________________________________
Two years from now, spam will be solved. - Bill Gates, World Economic Forum 2004


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david Eadenhall
Re: Confused over streaming compression settings
on May 6, 2009 at 12:10:18 am

Thank you so much Chris and Daniel for all this amazing information advice and knowledge. I am incredibly appreciative that you have spent the time in explaining all this to me.

Its so good to actually speak to people who are experts in this field as I was getting so desperate of what to do.

One last thing if I may: What is the difference between progressive download and streaming. When i am compressing my video, how do I know what type of download I am compressing for (progressive or streaming)? I have a streaming server set up so that my users can use the 'seek' function, will both these types of download be compatible with this, or is there one in particular that i should go for?

I really feel that now I can start doing proper tests on my videos and know what my parameters are finally.

Thank you so, so much again

Daniel


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Chris Blair
Re: Confused over streaming compression settings
on May 6, 2009 at 2:08:03 am

david Eadenhall What is the difference between progressive download and streaming. When i am compressing my video, how do I know what type of download I am compressing for (progressive or streaming)? I have a streaming server set up so that my users can use the 'seek' function, will both these types of download be compatible with this, or is there one in particular that i should go for?

Some of this may not be technically perfect, but it's a general explanation of the difference.

Progressive download sends the file (usually to a temporary location on your computer) to each end user, while true streaming feeds the video in real-time to end users (often called Video on Demand or VOD) or multicasts it to many users without having to actually cache or download it to your computer.

When they're both done correctly, end users usually don't see a difference between the two, as they both play the video as if it's in real-time.

Streaming is usually used for live webcasting, like what CBS did with the NCAA basketball tournament and NBC the Olympics, while progressive download is typically used for produced content.

There are exceptions of course, like when a corporation conducts traning via the internet and hundreds or even thousands of employees watch a pre-produced video. Of if your videos are so popular that hundreds of people may be watching your videos simultaneously. Or when a company does an online web event or promotion.

Streaming is usually more expensive because to do it reliably requires server side software and programming, and sometimes even special server hardware. It also uses a special transport protocol. Progressive download is less complicated and uses regular HTTP for sending files, and videos can often be stored right on your web server. Again...there are exceptions, as freely available software has streaming server capabilities built in, like VLC and others, but it's not for the faint of heart to set up.

Progressive download will start playing after only a few seconds of video has downloaded and continues to play as long as the download stays ahead of playback. You can also program in buffer or load times into flash metadata (the instructions that are typically part of a player skin that wraps the flash video) to ensure that a certain amount of the file downloads before playback begins, which helps keep the download ahead of playback. Some of the Flash encoding apps even offer simple options that allow you to specify the buffer time when encoding the video.

There are probably some technical things I haven't got quite correct, but that's the basic difference.

Here's some quick, concise articles that are helpful in explaining things further.

http://www.mediacollege.com/video/streaming/server.html

http://victoria.astonishingportal.com/electronicportfolio/addingvideo/video...

http://www.streamingmedia.com/article.asp?id=10952&page=1

As for encoding your video, virtually all the encoding we do is for progessive download, so I'm no help when it comes to preparing media for true streaming. But I don't think there's a whole lot of difference other than making sure it's coded to stream, and it's data rate is constant (CBR) as opposed to variable (VBR).

Others can probably explain the requirements better. But more than likely, progressive download will work for the majority of web video.

Chris Blair
Magnetic Image, Inc.
Evansville, IN
http://www.videomi.com


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Daniel Low
Re: Confused over streaming compression settings
on May 6, 2009 at 7:30:52 am

[Chris Blair] " while true streaming feeds the video in real-time to end users (often called Video on Demand or VOD"

Not quite, VOD has nothing to do with this, VoD is simply a type of service and can use either type of delivery method.

[Chris Blair] "When they're both done correctly, end users usually don't see a difference between the two, as they both play the video as if it's in real-time. "

Progressive downloads will generally always be higher quality. Full HD can be delivered easily by progressive download, that's nearly impossible for most people via RTSP.

[Chris Blair] "Progressive download will start playing after only a few seconds of video has downloaded and continues to play as long as the download stays ahead of playback."

Not quite, the time it takes for the clip to start to play is based on a combination of the viewers connection speed, the size of the file, and the length of the clip .







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Two years from now, spam will be solved. - Bill Gates, World Economic Forum 2004


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Daniel Low
Re: Confused over streaming compression settings
on May 6, 2009 at 6:55:05 am

There are a few major differences between Progressive Download and Streaming.

Progressive Downloads can be delivered from a normal webserver via HTTP
Streaming requires a dedicated streaming server and uses RSTP (Real Time Streaming Protocol)

Progressive Download saves a file to the viewers hard drive, as such it's very difficult to stop that file being copied.
Streaming delivery saves nothing to the hard drive.

With progressive download, you as the content creator, or owner controls the quality of the picture, users on all types on connection speeds see the same quality picture. Those on slow connections have to wait longer before they can start playing the video.

With streaming, the quality of the picture is determined by the viewers connection speed, those on slower connections sometimes see little more than digital soup, or if they do get a picture it seems more like a sequence of pixilated stills.

Progressive download is not suitable for long clips. say over 15 minutes
Streaming is suitable for long clips, even full length movies.

Most Flash delivery is progressive download.

VoD, or Video on Demand can be either.

Compressing for each is roughly the same only that when compressing for Streaming you have to pay strict attention to realworld bitrates. If for example you are targeting users on a 500kb/s connection, you wouldn't want the total datarate (audio & video) of your video to go over 425kb/s. With progressive download that could be as high as 1500kb/s.

When compressing for progressive download you can use CBR or VBR rate control, with streaming you can only use CBR.

There's much more, but those are the basics.

Hope that helps.

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Two years from now, spam will be solved. - Bill Gates, World Economic Forum 2004


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david Eadenhall
Re: Confused over streaming compression settings
on May 6, 2009 at 7:34:19 am

Dear Chris and Daniel

I just cant believe this site - the fact that two pros are taking the time to explain all this to me. I have spent months reading and re-reading up on all this and have not been able to take in this info. Its only since you both have taken the time to help me that I can finally understand this. Sorry to sound like a broken record, but thank you ever so much.

Well I have a server with a Wowza media streaming server installed. The reason that we went for a media streaming server is so that my viewers would be able to 'seek' to any part of the video and have it download from that point. I like the idea of being able to set my own bit rate to force the video to play at, so that I know how the end result for my viewers will look. So the sacrifice of this is that users with slower connections will have to wait longer before being able to start viewing if I go the progressive route?

Can one use the progressive download option with a media streaming server, or is that only for real streaming?

Am I right to believe that using a VBR is better than a CBR for progressive download?

I have tried compressing videos using Final Cut Pro, Quicktime Pro, Mpeg Streamclip and Adobe Media Encoder but there has been no apparent setting to choose whether my final compressed video is going to be for progressive download or true streaming - am I missing a setting here or do other parameters govern this? Maybe I have overlooked something here. I only seem to be able to set frame rates, data rates, frame sizes, quality, deinterlacing, CBR/VBR etc.

Thank you again

Dan






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Daniel Low
Re: Confused over streaming compression settings
on May 6, 2009 at 9:18:40 am

[david Eadenhall] "So the sacrifice of this is that users with slower connections will have to wait longer before being able to start viewing if I go the progressive route?"

Yes.

[david Eadenhall] "Can one use the progressive download option with a media streaming server, or is that only for real streaming?"

No need (you just need a simple webserver for progressive download) but it's probably possible, have a chat with the Wowza support guys.

[david Eadenhall] "Am I right to believe that using a VBR is better than a CBR for progressive download?"

It depends on the kind of content; a simple interview, for example, will not benefit from VBR, an action movie would.
VBR will make for a far more efficient encode, meaning the file size will generally be smaller, as it has allocated data more meaningfully. 2-Pass is the the best way to encode VBR. Actually 2-pass is the best for CBR too. If you have the luxury of time.

Final Cut, MPEG Streamclip and Quicktime Pro are not the tools of choice here. Adobe Media Encoder is pretty good and should have presets for both streaming and download, I don't use it so I can't be sure.

The best tools for the job are Apple compressor (which you should have) and Episode.



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Two years from now, spam will be solved. - Bill Gates, World Economic Forum 2004


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david Eadenhall
Re: Confused over streaming compression settings
on May 8, 2009 at 9:43:16 am

Hi there Daniel and Chris

I would ideally like to make my videos available via progressive download as the idea that I can control the quality that ALL my viewers will see, really appeals to me. I wouldnt really be happy knowing that if I stream my material, some viewers will think my videos are poor quality because they dont realise that the speed of their connection is making these videos look bad. The picture quality of my videos is very important really, as its a shame to destroy the quality from our HD source.

I would also like to make my videos available for download to a hardrive (in a zip folder) as well as for immediate viewing online. That way I can be confident that whatever set up our user will have, they will be able to actually view the videos in some way.

My question is if I offer a video for progressive download and also for download via zip, am I effectively going to double my bandwidth usage (users might progressively view the video online, then decide to download a copy to their hardrive). If I decided to stream the video instead, so the user could still view the video right away before deciding whether to also download a zip copy, would that use up alot less bandwidth?

If one views progressive downloads in a normal browser, can you still have the option of being able to maximise the video to full screen, or are you limited to the exact frame size of your original video file in the browser?

Once again, thank you ever so much for all your help over the last week, Im just so appreciative to you!

Dan


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Daniel Low
Re: Confused over streaming compression settings
on May 8, 2009 at 10:13:37 am

[david Eadenhall] "My question is if I offer a video for progressive download and also for download via zip, am I effectively going to double my bandwidth usage"

Yes, pontetially if it the same video you use for both types of downloads.

[david Eadenhall] "If I decided to stream the video instead, so the user could still view the video right away before deciding whether to also download a zip copy, would that use up alot less bandwidth?"

Yes, if the streaming clip is at a much lower datarate than the downloadable zip version.
[david Eadenhall] "If one views progressive downloads in a normal browser, can you still have the option of being able to maximise the video to full screen, or are you limited to the exact frame size of your original video file in the browser?"

You are limited by the capabilities of the browser and the browser plug-in. What player are you considering using? If it is a Flash player you'll need to script a button that will allow it to playback at fullscreen.

Alternatively, look at the way Apple delivers it's HD Quicktime movies: http://www.apple.com/trailers/#section=justhd

Anyone with Quicktime Pro (or Quicktime Alternate) can save any of these movies directly to their hard drives and only use up the bandwidth once.



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Two years from now, spam will be solved. - Bill Gates, World Economic Forum 2004


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david Eadenhall
Re: Confused over streaming compression settings
on May 8, 2009 at 10:22:09 am

Hi there Daniel

I cant believe how quickly you responded!!!!!

I have Flowplayer on my server that I am currently testing with our videos. Is this s a good choice?

Those Apple trailers consistently stun me, the quality, the content, the immediacy etc - sensational! What sort of compression techniques do they use, its unbelievable?

How have they been able to allow the users to only use the bandwidth once by watching and saving the file in one go - that sounds like the perfect solution?

Thank you so much my friend

Dan


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Daniel Low
Re: Confused over streaming compression settings
on May 8, 2009 at 10:40:46 am

I don't have any direct expereince with Flowplayer but it appears to have a fully featured toolset including a bandwidth checker:

http://flowplayer.org/plugins/streaming/bwcheck.html

[david Eadenhall] "Those Apple trailers consistently stun me, the quality, the content, the immediacy etc - sensational! What sort of compression techniques do they use, its unbelievable?"

They get hold of the best quality source content to start with and have a team of skilled compressionists working to generate the outputs using a variety of software encoders including compressor and cleaner. Nearly all content is encoded to H.264.

[david Eadenhall] "How have they been able to allow the users to only use the bandwidth once by watching and saving the file in one go - that sounds like the perfect solution?"

As the file is being progressively downloaded, it's already there on the hard drive, the Quicktime player then just enables the saving (moving) of it to a convienient location for the user.



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Two years from now, spam will be solved. - Bill Gates, World Economic Forum 2004


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david Eadenhall
Re: Confused over streaming compression settings
on May 8, 2009 at 10:55:13 am

"As the file is being progressively downloaded, it's already there on the hard drive, the Quicktime player then just enables the saving (moving) of it to a convienient location for the user."

Is this possible to set up on my server, or is this a very complicated process to go through? This surely would be an ideal solution.

Take care my friend

Dan


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Daniel Low
Re: Confused over streaming compression settings
on May 8, 2009 at 11:55:29 am

[david Eadenhall] "Is this possible to set up on my server, or is this a very complicated process to go through? This surely would be an ideal solution."

I'm fairly sure it's possible with a Flash player but I've not seen it done and I wouldn't know how to do it. One for the Flash forums.

With Quicktime, there'd be nothing to do at all, it just does it.



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Two years from now, spam will be solved. - Bill Gates, World Economic Forum 2004


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david Eadenhall
Re: Confused over streaming compression settings
on May 8, 2009 at 12:05:53 pm

Dear Daniel

May I trouble you with just one LAST question?

If I opt for proper streaming, is there anyway to be able to control the quality that all my viewer's will see, or will it be their internet connection speed that holds full control over that? I just want to know what my viewers will be seeing.

We are offering free video clips to advertise our purchasable videos. If we stream a video and their connection is bad, the quality of our video clip wont look good at all and might subsequently put them off buying our full videos. This is why im so concerned with the output quality.

Thank you again my friend

Dan


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Daniel Low
Re: Confused over streaming compression settings
on May 8, 2009 at 1:04:48 pm

[david Eadenhall] "If I opt for proper streaming, is there anyway to be able to control the quality that all my viewer's will see, or will it be their internet connection speed that holds full control over that? I just want to know what my viewers will be seeing."

The connection speed has a direct impact on the image quality. If the connection speed drops, then the picture will eventually degrade and even dissapear.







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Two years from now, spam will be solved. - Bill Gates, World Economic Forum 2004


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Mike McGuiness
Re: Confused over streaming compression settings
on Jun 9, 2009 at 5:49:00 am

Some tricky questions here, as the options are so varied and ones persons idea of quality is not the same as anothers.

h264 can be streamed in flv or mp4 via Flash Media Server or Wowza Media
There are some ways to test such as mogulus or FLV Hosting that might help


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