Stereo/MTS NBTV.

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Stereo/MTS NBTV.

Postby olbermann » Fri Sep 18, 2015 7:51 pm

hi everybody

I've been thinking about a way to improve the way files are carried for exchange and playback.
Talking about encoding and playback software. eg video2nbtv

at first instance the sampling frequencies used are quite inflexible I think, for most 32line 400hz line 12 and half frames per sec. using sampling freq below 22khz for B/W low quality videos are ok. even 4-8 kHz room for video is enough to watch intelligible forms and movements.

second there's a waste of space on left channel for only baseband mono audio.then I started testing some files that might content Stereo Sound on left channel and or More than one video, audio channels using AM Qam modulation inside a WAV file.
https://www.youtube.com/watch?v=XE4C-Pt4ioA
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Re: Stereo/MTS NBTV.

Postby Lowtone » Fri Nov 13, 2015 6:48 am

i told this here
viewtopic.php?f=6&t=2003

Here are my thougts

1st, we could abandon the 44,1kHz system and replace it by 48 and/or 96
why? because 44 is only used on CD, and CD will fade out before the end of the decade
also 48 is the standard for DAT and DVD since the 90's, and 96 is the new common format for Hi-res audio in music industry + also Blu rays.

Stéréo :
Your system is inspiring, but it relies on Qam, wich is going to be obsolete too.
Your system can be interesting in case of radio wave transmission, where bandwith is really limited.
But as for files i propose two systems to implement stéréo :

1st : for those who wants to stick with CD format for a while and use simple normal stereo files.
We can have the sound in stéréo like a standard Cd audio + ontop of the sound adding the NBTV picture signal on both channels
Then, the receptor needs to invert the phase and reinjects it. It will extract the center channel ( some sound editing softwares can do this too, it's easy )
So from 2 channels we got 3 channels

2nd : a drastic change in format and profits of the new 5.1 format.
5.1 files are done for surround sound, normaly it works with a pair of front stereo, back stereo + a center channel for voice, and a bass channel.
Here we coud use the stereo for the sound, and the center channel for the picture.
3 channels are used, but there is 3 other ones left
Why not using a multiple encoder software that output 30line, 32line, 60line common formats and having them on the different channels
remains one. This cound be use for bass, but do we need it ?
or language translation track, data?, or another (4th) video channel in another format
( edit : colour ! )

So we could share one file with everything, stereo, + up to 4 different NBTV format, so everyone will be happy since we can have different televisors.

There are advantages and drawbacks.
Advantages : now most computers have 5.1 outputs, DVD players, and Blu Rays players can read and output this format too
Drawbacks : drastic change in the system, files are really huge !

( but now HDD are huge too and internet is faster and faster )

Maybe we can also find a compromise and only use 2.1 files
r a d i o P T T v i s i o n
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