File size is always an issue. Especially so if you think a 10 min. 120  
megabyte file ain't no thing.

With a 1.5 megabit connection the download will take 10:40 - ASSUMING you  
can use all your available bandwidth for the download (not going to  
happen).

More realistically you will get downloads in the 80-90 kilobytes/second  
range (which is what I'm usually getting from video services). In that  
case the download will take 23 minutes (230% of the video duration).

 From blip.tv I rarely get more than 50 kilobyte/sec (and my connection is  
a 1.5 mbps cable connection. Very common here). Then the download is a 41  
minute download (ie. it takes 4 times as long to download as it takes to  
watch).

To avoid the click-wait problem you will have to encode at a decent  
bitrate. 50 kb/s (700kpbs) is a good target. That would make your 10  
minute video be 30 megabytes. A much more realistic scenario if you don't  
want your viewers to wait for your video to download.

- Andreas

Den 24.04.2007 kl. 00:23 skrev Bill Cammack <[EMAIL PROTECTED]>:

> Why exactly is it that you're worried about file size?
>
> If you're talking about a 120mb file, and it's a 10-minute episode,
> it's NOT going to take 10 minutes to download the 120 megs, so there's
> no significant loss in the viewer's quality of experience.
>
> Are you concerned that the file won't play until it's downloaded?
> What's the negative issue for the viewer if your files are that size
> for that program length?
>
> --
> Bill C.
> BillCammack.com
>
>
> --- In [email protected], "wazman_au" <[EMAIL PROTECTED]> wrote:
>>
>> Guys guys guys,
>>
>> Are you really content with imposing such a bloated file format on
>> your viewers?
>>
>> Does 120MB for a 10-minute episode seem reasonable, for example?
>>
>> Not to me it doesn't, when it's about six times the size of what I've
>> been putting out so far - and when my source videos aren't hi-def or
>> anything, just garden variety Mini-DV at 4:3.
>>
>> I have managed to produce a 640x480 video that is 10 minutes long and
>> takes up about 50 megs but because of this "baseline low-complexity"
>> issue it won't iPod.
>>
>> There are such simple ways of chopping down the size - such as
>> changing sound from stereo to mono - if you can control the
>> parameters, which you can't with Export to iPod in QT Pro.
>>
>> Waz
>>
>>
>>
>>
>>
>> --- In [email protected], "Bill Cammack" <BillCammack@>
>> wrote:
>> >
>> > Good call, Bill.  That's right along the lines of what I was thinking.
>> >
>> > --
>> > Bill C.
>> > BillCammack.com
>> >
>> > --- In [email protected], "Bill Shackelford"
>> > <bshackelford@> wrote:
>> > >
>> > > My video feed enclosures support ipod,iphone,itv and quicktime.. I
>> > just use iPod .m4v
>> > > format. So in quicktime export to ipod and get a 640x480 video that
>> > anyone can watch.
>> > > The only thing that *might be worth while to instead of .m4v would
>> > be .mp4 video that
>> > > you can play in all of apples stuff in addtion to  PSP... but .mp4
>> > videos kinda suck to
>> > > playback over the web in my opinion.
>> > >
>> > > My feed:
>> > >
>> > > http://feeds.feedburner.com/billshackelfordcompod
>> > >
>> > > All my links in my podcast rss file point to flash video on my site
>> > and the enclosures are
>> > > the .m4v files.
>> > >
>> > > I have also been provideing .3gp video.. but no no one has been
>> > looking at those.
>> > >
>> > > my mobile site: http://m.billshackelford.com
>> > >
>> > >
>> > >
>> > >
>> > >
>> > >
>> > > --- In [email protected], "Bill Cammack" <BillCammack@>
>> > wrote:
>> > > >
>> > > > Steve: That's precisely what I was thinking. Subscribe to the feed
>> > > > that works for you.  http://JetSetShow.com , for instance has
>> about 6
>> > > > feeds.
>> > > >
>> > > > Waz: Personally, if I were concerned about a video being
> playable on
>> > > > iPods as well as AppleTV and having only one feed for the
>> reasons you
>> > > > mentioned, I'd aim for the lowest common denominator.  I haven't
>> > > > looked into AppleTV, so I'm not sure this is possible, but the
> data
>> > > > rate for iPods is lower than the data rate for AppleTV, so I'd
>> make a
>> > > > video to iPod spec and test it through iTunes to make sure it also
>> > > > runs on AppleTV.  You might lose some resolution that way, but
>> if you
>> > > > insist on having only one feed, that's the only way I can see it
>> > > > working.  Again, assuming there IS a LCD that you can encode to.
>> > > >
>> > > > --
>> > > > Bill C.
>> > > > BillCammack.com
>> > > >
>> > > > --- In [email protected], "Steve Watkins" <steve@>
>> wrote:
>> > > > >
>> > > > > I guess the assumption would be that your viewers would
>> subscribe to
>> > > > > one feed or the other, depending on which hardware they owned.
>> > > > >
>> > > > > Its not ideal but it may be ideal for some viewers, depending
>> on how
>> > > > > fussy they are about getting the best possible qualiy on their
>> > device.
>> > > > >
>> > > > > Unfortunately these issues are unlikely to vanish. Because for
>> > all my
>> > > > > evangelising about mpeg4 and h24 standards, this is unlikely
>> to boil
>> > > > > down to one common subset of h264 just so long as theres so much
>> > > > > variation in decoding power between devices. Battery life is
> a big
>> > > > > issue for mobile devices and high-def TV's arent very
> forgiving of
>> > > > > low-quality/low res footage, so it may get worse. If
> high-def web
>> > > > > video wasnt so absurdly huge in comparison to what we're
>> mostly used
>> > > > > to, there would probably be even more confusion and conflicting
>> > > > > pressures already.
>> > > > >
>> > > > > The jump from 320x240 t 640x480 is quite significant, I know
> Apple
>> > > > > mailed people advising everyone to change, but theres certainly
>> > merit
>> > > > > in considering still offering a 320x240 version at this
> time. You
>> > > > > could for example keep the ipod feed at 320x240 and offer the
>> > 640x480
>> > > > > version specifically for apple TV. Because Im not sure how
>> many ipod
>> > > > > people use the TV out, and they might hate the increased
> filesizze
>> > > > > more than they appreciate the higher res they may never get to
>> see.
>> > > > >
>> > > > > Cheers
>> > > > >
>> > > > > Steve Elbows
>> > > > >
>> > > > > --- In [email protected], "wazman_au" <elefantman@>
>> > wrote:
>> > > > > >
>> > > > > > Bill,
>> > > > > >
>> > > > > > Can't see how that would work, because Apple TV syncs with
>> > iTunes on
>> > > > > > your computer, which means your iPoddable feed.
>> > > > > >
>> > > > > > You could have a separate feed but this would effectively be a
>> > > > > > separate podcast - and would you expect your viewers to
>> > subscribe to
>> > > > > both?
>> > > > > >
>> > > > > > Waz
>> > > > > >
>> > > > > >
>> > > > > >
>> > > > > >
>> > > > > > --- In [email protected], "Bill Cammack"
>> > <BillCammack@>
>> > > > > > wrote:
>> > > > > > >
>> > > > > > > Work-around #4
>> > > > > > >
>> > > > > > > 1) Export for AppleTV
>> > > > > > > 2) Export for iPod
>> > > > > > > 3) Two different feeds
>> > > > > > >
>> > > > > > > Bill C.
>> > > > > > > http://BillCammack.com
>> > > > > > >
>> > > > > > > --- In [email protected], "wazman_au"
>> <elefantman@>
>> > > > wrote:
>> > > > > > > >
>> > > > > > > > Stupid bloody Apple, why do they DO things like this????
>> > > > > > > >
>> > > > > > > > Folks, this is a tough one, and yes, I've read through the
>> > > > > > > Casey-initiated thread. Good start
>> > > > > > > > but sadly optimistic.
>> > > > > > > >
>> > > > > > > > The question is, how do we pump out vids that are 640x480
>> > and have
>> > > > > > > the "baseline low-
>> > > > > > > > complexity" profile, thus being both iPod and (presumably)
>> > > > Apple TV
>> > > > > > > compatible?
>> > > > > > > >
>> > > > > > > > Baseline can be selected when exporting with your own
>> > > > settings, but
>> > > > > > > the "low-complexity"
>> > > > > > > > sub-option cannot. According to Apple's developer spec,
>> > > > > > > low-complexity has been defined
>> > > > > > > > by Apple for the iPod, and it seems to be restricted to
>> > the Export
>> > > > > > > for iPod option, which
>> > > > > > > > cannot be configured.
>> > > > > > > >
>> > > > > > > > When exporting an iPod video, QuickTime chooses
>> automatically
>> > > > > > > whether to use "baseline"
>> > > > > > > > or "baseline low-complexity" - in a nutshell, anything
>> > upwards of
>> > > > > > > 320x240 gets low-
>> > > > > > > > complexity. Gory details here:
>> > > > > > > >
>> > > > > > > > http://developer.apple.com/technotes/tn2007/tn2188.html
>> > > > > > > >
>> > > > > > > > Three possible workarounds. I am not in front of QTPro
> right
>> > > > now so
>> > > > > > > will try later:
>> > > > > > > >
>> > > > > > > > 1) Use the Export for iPod option with the source vid
>> sized at
>> > > > > > > 640x480 - this will goad
>> > > > > > > > QTPro into using low-complexity - and then find some way
>> > of saving
>> > > > > > > the resulting video
>> > > > > > > > _again_ with a chopped-down bitrate, perhaps by doing a
>> > "Save as
>> > > > > > > ..." but without re-
>> > > > > > > > encoding.
>> > > > > > > >
>> > > > > > > > 2) Do it the other way round - export at the bitrate etc.
>> > that you
>> > > > > > > want, then run it through
>> > > > > > > > the iPod export. The developer spec suggests QT iPod
>> exporter
>> > > > using
>> > > > > > > a 640x480 source
>> > > > > > > > file will pick its own bitrate according to a complex
>> formula
>> > > > ("DR =
>> > > > > > > { (nMC * 8 ) / 3 } - 100"
>> > > > > > > > I kid you not, check out the developer link above) between
>> > 700 and
>> > > > > > > 1500kbps. But maybe
>> > > > > > > > if the source file is already lower, it won't jump up the
>> > bitrate
>> > > > > > > too shockingly. The MC in
>> > > > > > > > the equation stands for "macroblock" and if the number of
>> > > > these can
>> > > > > > > be reduced in the
>> > > > > > > > source file (how? Dunno) then, doing the maths, you are
>> headed
>> > > > for a
>> > > > > > > smaller result.
>> > > > > > > >
>> > > > > > > > 3) Resize your source video to 640x480, whack it through
>> > > > Export for
>> > > > > > > iPod and hope the
>> > > > > > > > filesize is not too bloated. As in the formula above, this
>> > should
>> > > > > > > produce something
>> > > > > > > > between 700kbps and 1500kbps, although Apple doesn't say
>> > > > whether the
>> > > > > > > audio is
>> > > > > > > > included in that bitrate (AAARGH!).
>> > > > > > > >
>> > > > > > > > I found to my horror this afternoon that my carefully
>> crafted
>> > > > > > > 640x480 recipe with
>> > > > > > > > meticulously pared down video and sound bitrates that
>> > delivered a
>> > > > > > > file of 5MB/minute that
>> > > > > > > > looks alright on the telly via laptop S-Video cable
> doesn't
>> > > > work on
>> > > > > > > the iPod.
>> > > > > > > >
>> > > > > > > > I am just about ready to tell Apple where to shove
> their TV
>> > > > box ...
>> > > > > > > and all of the above still
>> > > > > > > > leaves the question unanswered: will the aforementioned
>> oblong
>> > > > > > > suppository PLAY H.264
>> > > > > > > > BASELINE LOW-COMPLEXITY???
>> > > > > > > >
>> > > > > > > > Anyone got one of these boxes?
>> > > > > > > >
>> > > > > > > > That's all for now. I know none of the above is tested
> but I
>> > > > thought
>> > > > > > > I'd post now while my
>> > > > > > > > blood is up, and to give others the chance to look for a
>> > solution.
>> > > > > > > >
>> > > > > > > > Waz from Crash Test Kitchen
>> > > > > > > > http://www.crashtestkitchen.com
>> > > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>>
>
>



-- 
Andreas Haugstrup Pedersen
<URL: http://www.solitude.dk/ >

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