OT: Best Option for Web Delivered Voice Overs

Web Admin Himalayan Academy katir at hindu.org
Sun Mar 14 15:15:31 EDT 2010


OK, well no one responded to my actual requirements: fastest audio work 
flow and as small as possible, I should have added: native RunRev 
platform... as much as possible...

So I went ahead and did my experiments using Revolution as my recorder. 
Samson COIU USB Stude condensor USB mic (love it... inexpensive too. on 
sale now...) I had to learn about the answer record dialog and all the 
different settings. One opaque point is that if you choose a recording 
format that does not support the codec you select from the available 
codec supplied by QT then it usesa default codec and you can't really 
know what that is so logging exact scenarios/tests is difficult if 
settings are changing under the hood by QT.

At any rate, I tested many, many combinations. Len's basic point was 
manifestly confirmed big time. There was really nothing to be gained by 
using any low compresssion initially. well not exactly. avoid raw... You 
could record  a slide caption VO -- 8 seconds long using uLaw save to 
.au  and you get an apparently smaller file at about 400k. Quality quite 
poor. Record 8 seconds at 64bit floating  44kh sample size 16 to WAV or 
aiff and you get a big 636K good quality file; but when you run these 
both thru Switch to MP3, joint, 48 bps  you end up with a ~44K file 
either way... with the result from au being really bad, but the 44k.mp3 
that that started out as a big wave file is surprisingly high quality 
for that size.

So old axiom proved again, garbage in --> garbage out; big diamond in 
and the little gem that comes out is still a diamond.

So then, and this is the really interesting part:

If I take that 44 K.mp3 file and convert to au with Skitch: codec PCM 
8bit; sample rate 6000 channels: mono... I get a 44K.au file that still 
has great quality that can be imported back into Revolution. Streaming 
44K caption VO's should not be a problem even for fairly low bandwidth 
users. And if we wanted to do this as a revlet and let the stack contain 
the audio we can do that also.

OM shanti
Sivakatirswami





On 3/12/10 4:41 PM, Joe F. wrote:
> Len's point about noise is key.
> You want to set up a small area that's quiet, muffled if possible.
> Blankets or drapes on walls and windows for zero reflected sound.
> Use compression/limiting to record a high level (above the noise 
> floor) signal.
> If it's quiet when nobody's talking and the level is good it will 
> sound "professional".
> If it sounds too "dry" add a touch of reverb, season to taste.
>
> If I were doing it I'd use basic Mac tools: QuickTime Pro, iMovie, 
> Garageband. Simple, quick, compatible, and integrated.
> The best quality for me at the moment is h.240 with AAC audio. Highest 
> quality, smallest file.
> You see it a lot in Flash movies lately so it's generally supported on 
> the users computer.
> You can fiddle with settings endlessly but it's mainly the data rate 
> that will affect the size/quality ratio.
> You should be able to get very good quality 640x480 (that looks good 
> full screen) at less than 5 MB/minute.
> Also AAC has a "voice only" optimized setting for the audio.
>
> Script everything and if possible add the script as a text track to 
> your working master.
> First- without a script event the simplest narration has to be done 
> more times than with.
> Second- The text track has multiple uses, primary being subtitles.
>
> Speech is still not too great on Windows from the little experimenting 
> I've done.
> Even on the Mac it depends on matching a good voice with the text to 
> be spoken.
> Sometimes you'll be lucky and the pronunciations of every word will be 
> perfect; other times you will need to experiment with phonetic 
> spellings to get it right.
> The text track can be used for that, and if one day text-to-speech is 
> perfect on all platforms...
>
> If the videos have computer screen content, another way to go is a 
> screen recorder like Screenium.
> You can record anything playing on the screen and add a voiceover to 
> it. Then it has all these little extras.
>
> Joe F.
>
> On Mar 12, 2010, at 8:05 AM, Len Morgan wrote:
>
>> If it were me, I'd do my "development" using wave files.  The format 
>> is well documented and allows fairly easy editing in rev.  When you 
>> are FINISHED, convert to mp3 or whatever format you want.  As the 
>> owner of a recording studio, I always try to stay with the highest 
>> quality and (unfortunately) the format with the most data to work 
>> with.  Every time you convert the data (for example wav->mp3) you are 
>> going to introduce noise and loose some of the original information.
>>
>> len
>>
>>
>> On 3/11/2010 7:14 PM, Sivakatirswami wrote:
>>>
>>> 5) Production Work Flow Strategies: Any other insights will be 
>>> appreciated. you can get a Samson USB mic these days really cheap on 
>>> Amazon.dot and the quality is excellent. It would be marvelous to 
>>> build a stack, show slides, record on the fly, save and deploy, but 
>>> I don't think it's going to be that easy... Especially if MP3 is the 
>>> optimum format, it means stepping out of revolution into Audacity.. 
>>> Processing clips and going back to set up the QT player to the 
>>> external file.  Or assuming you were really, really good with 
>>> narration and required no edits:  Switch to batch process all the 
>>> narrations at once after saving as aiff --> process out to .mp3 ... 
>>> 15 short VO's at average 2-8 secs each will be fast.
>>
>>> Sivakatirswami
>>>
>>
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