[Dtb-talk] A question about preferred book formatting

[Greg Kearney]

We do find tone indexing from time to time but it is not very common  
even from the materials we got from over east. When it is there it is  
very useful and we do use it. With vision you can spot those tone in  
the wave form faster and with greater accuracy than the programs can  
detect it. Too bad they were not all tone indexed. I don't understand  
why they would have stopped even with 2 track tape you could have done  
that. Oh well. Now if I could only figure out how to encode pages as  
we record with Dolphin.


Gregory Kearney
Manager - Accessible Media
Association for the Blind of Western Australia
61 Kitchener Avenue, PO Box 101
Victoria Park 6979, WA Australia

Telephone: +61 (08) 9311 8202
Telephone: +1 (307) 224-4022 (North America)
Fax: +61 (08) 9361 8696
Toll free: 1800 658 388 (Australia only)
Email: gkearney at gmail.com

On 30/01/2010, at 2:11 PM, Tim Gillett wrote:

> Greg,
>
> That's great there's  indexing tone detection software available.  
> From memory I think it was usually about a 50hz sinewave.
>
> If it's any help,  ABWA's inhouse productions from about the early  
> 90's to 2007
> when they changed to digital recording would be unlikely to contain  
> index tones.
>
> There may however be tones on some inhouse titles recorded from  
> about 1987 to the early 90's.
> I remember at that time sourcing some Australian made add-on tone  
> indexing units
> and installing them into at least some of the 4 recording studios.
>
> As well, some  study materials recorded by volunteers at home in  
> this period were recorded on the APH GE type
> cassette recorders which had a built in tone index recording  
> facility which the vollies were trained to use.
> These titles would be on a mixture of 2 track and 4 track cassette  
> formats.
>
> Also, I seem to recall productions ordered from fellow Australian  
> producers RBS and RVIB (now Vision Australia)
> contained tone indexing, as well as fast wind voiced chapter indexing.
> It may however be difficult to outwardly identify these as RBS or  
> RVIB productions if they were "rebadged".
> But I guess if the tones are there the software will pick them up.
>
> On a slightly more technical note, it may in some cases be necessary  
> to play around
> with the tone detection software's "threshold" settings so as to  
> avoid the problem of tones
> that are too quiet for the detector and get missed, or on the other  
> hand, avoiding false triggering due to studio noises,
>  microphone "plosives" etc fooling the software into thinking they  
> are actually index tones.
>
> The same might apply for the software's "tolerance" for tones that  
> were not quite standard in  frequency.
> Analog tape's time domain (and therefore frequency) accuracy was not  
> nearly as stable as digital's.
>
> These days, with the benefit of sophisticated error correction  
> software,
> we just take it for granted a digital copy will be essentially a  
> perfect replica of the original.
>
> Nowadays, all the fun's been taken out of it!  (joke)
>
> Cheers, Tim
>
> Tim Gillett
> Audio/Electronics Technician
> Perth, Western Australia
>
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