<!-- Some styling for better description lists --><style type='text/css'>dt { font-weight: bold;float: left;display:inline;margin-right: 1em} dd { display:block; margin-left: 2em}</style>
maury: oh, i am trying to build a channel file for Toronto
<br> I am basing it on the one for calgary
<br> i have collected the useful information...
<br> but the frequencies in the files don’t make any sence
<br> none of them match the actual UHF frequencies
<br> any ideas?
merbanan: <u>maury</u>: how do they not make sense ?
maury: for instance, calgary has a channel listed for 515 MHz. That is not an actual frequency used by ATSC
<br> in fact, none of the frequencies in any of the ATSC files match up with actual channels
merbanan: how large is the offset and is it constant ?
<br> ok I found the info now
<br> 515 is the frequency of the middle of the band
maury: you can find the actual freqs on the wiki - I know it’s acutrate, I wrote it
merbanan: the lower edge is 512
<br> the higher is 518
maury: so take the average?
merbanan: looks like you have a 6MHz channel
maury: indeed yes
merbanan: 515 -3 = 512
<br> 515 + 3 = 518
maury: ok so I will add three to all the freqs I have
merbanan: so the value 515 is the middle frequency
maury: question two: is there any reason the atsc-center-frequencies list is not sorted?
merbanan: I am not sure you are supposed to do that
maury: If I add three to the lower edge, which is the number that I have on my list, I will get the center and it seems that is what they want in the list
merbanan: but if you get actual reception by tuning to that frequency then it is correct
<br> you may sort the list however you want
maury: ok that’s good
<br> is there a format doc anywhere? I have lots of other info I could add. Channel names, tower locations, ERP, etc.
merbanan: afaik you only specify the mux frequencies and leave it at that
<br> there are comments you could add though
maury: yeah that’s what i did. it would be nice to expand the format a bit
merbanan: for what use ?
maury: ERP and location lat/long would be VERY useful! it would allow you to figure out what channels are really available
<br> and channel name, well, that seems useful!
merbanan: you get the channel names by scanning the muxes
maury: but don’t you get the channels that way too?
merbanan: well you do in dvb-t
<br> I assume you have digital tv
maury: yes. the hardware does the scan internally, so it’s not clear why there is this file
merbanan: not following you
maury: well this file appears to be telling the tuners where to look for stations, yes?
merbanan: ok, what file do you actually talk about and can you pastebin the content of one of them ?
maury: do you have file “ca-AB-Calgaryâ€
<br> it is part of the dtv-scan-tables git repo
Sashmo: hey maury
<br> http://pastebin.com/TiBYg1ad
<br> this is what you are looking for
<br> had the same issue with that my self
maury: thank you!
Sashmo: the headache is that what ever list you are looking at is wrong
<br> you need to look at wikipedia
<br> for example
<br> CH CH
<br> https://en.wikipedia.org/wiki/CHCH-DT
<br> digital slot is actually 15
<br> not 11
maury: another cannuck I assume?
Sashmo: ;)
maury: yes I know, I just find the “center frequency†confusing, it doesn’t match up with anything anyone actually uses.
Sashmo: https://en.wikipedia.org/wiki/CITY-DT
<br> is 44
<br> not 57
maury: lower band, sure. upper, maybe. video carrier, ok i can see that argument.
<br> but “center frequency�!?!
Sashmo: 44 650 - 656 650.31 653
<br> ues the roudned freq
<br> so 653
maury: yeah i get it
<br> still, why even have these files? my hardware has the table in the eeprom
Sashmo: ummmm
<br> probably not
<br> what device?
maury: kworld 435. apparently I am a masocist
Sashmo: ahhh pacific mall model
<br> you got the -Q model right?
maury: yeah, needed that like a hole in the head
<br> axctually im sure it works fine on lintel or rpi
<br> but I convinced myself it would work on odroid
<br> it does not
Sashmo: blah..... thats not gonna work
<br> I think somone hauppague drivers for android
<br> of the linux branch
maury: yeah, I’m thinking of getting one. i got the kworld because my hauppague blew up out of the box
<br> bad luck i guess
Sashmo: good luck... pm me if you need help
maury: ok thanks!
Sashmo: side note to the room..... anyone remember how to modify the DVB drivers in linux to support more than 8 devices?
merbanan: <u>maury</u>: the only thing this file does is listing the frequency of the muxes
maury: yeah, i figured
merbanan: and that is the only thing that should be in them
<br> your viewer software should be able to load this file and scan the muxes for channels
maury: sure, but why have local lists then? if we’re just going to scan, why bother with a Calgary list, for instance?
merbanan: there is a difference between scan and blind scan
<br> your use of scan means blind scan
Sashmo: maury..... forget blind scan.... there is no such thing in Canada for ATSC
<br> the ATSC has a spec
<br> its that list
<br> cant go outside it
<br> CRTC things
maury: no, it’s not that list, that list is years out of date
Sashmo: and Industry canada
<br> if you are doing DVB, then blind scan makes sense becuase there is no rule on what freq and sr to use
maury: nothing about 50 has been in use for quite a while now, and VHF-low is long gone
merbanan: <u>Sashmo</u>: not really true
<br> <u>maury</u>: anyway if you have this file you only need to check ca 5 frequencies
<br> without it you need to check all the channels that are part of the dtv system you use
Sashmo: <u>merbanan</u>: yes.... the ATSC spec is set in the frequencies, you cant use it for other things unless you have a license to do it, dont get me wrong, in Toronto there are some people that are useing the same ATSC frequncy and modulation even have PMT tables, but they dont broadcast video.... but to get that license to be in that space it needs to be the ATSC spec.. no going outside it..... as long as you are talking about TV.... if not, then you co
<br> uld be .1% right
maury: sure, but that list is VERY MUCH subject to change
<br> it would seem safer to just use the master list every time, which would catch any new channels or moved allocations
merbanan: <u>maury</u>: this file only list the muxes, nothing about channels
<br> to get new channels you need to do a rescan
maury: wait, when you say mux, do you mean “an allocation of bandwidth that carries one or more channels�
merbanan: if they have changed anything
maury: if so, “mux†and “channel
<br> are synonomous
merbanan: “an allocation of bandwidth that carries one or more channels” yes
maury: yeah, in canada we don’t really do the multiple-channels-per-mux thing
merbanan: you don't move around the actual muxes to other frequencies that much
<br> in dvb-t that is
maury: true, but using Calgary example, there are 8 DTV channels and 6 analog
<br> and they aren;’t even in the frequencies in the file, they’ve moved
merbanan: <u>maury</u>: well add them then
<br> and submit the changes
maury: but that is my point - why even have this file if it’s subject to change? why no just use the master list ever time?
merbanan: because the master list is longer
maury: ok perhaps I am missing something here.
<br> if i use the Calgary list, everything is broken
<br> so I would use master list to rescan
<br> right?
merbanan: do a blind scan with w_scan
maury: ok
<br> so when do I ever want to use the other list?
merbanan: I actually don't know what the master list you are talking about is
maury: us-ATSC-center-frequencies-8VSB
merbanan: ahh
<br> well feel free to use that list
maury: for what?
<br> no sorry, let me re-phrase
<br> I can see why you would use us-ATSC-center-frequencies-8VSB
<br> it lists everything
<br> but I cannot see any reason to use ca-AB-Calgary - or anything like that
<br> is there some feature of v4l that makes these short lists useful?
merbanan: scan time
maury: but they’re WRONG. that doesn’t save time, that makes much much more time and frustration
merbanan: make them right
maury: unless there is some difference between “scan†and “blind scan†perhaps?
merbanan: blind scan doesn't use and table
<br> -> takes a long time
<br> scan with large table
maury: OHHHH, so how does blind scan do it’s thing?
merbanan: -> takes less time
<br> scan with correct info
<br> -> takes even less time
<br> it tunes to a frequency that it thinks might have some mux and listen for data
maury: ok. and how does it know what frequencies to guess at? eeprom?
merbanan: you can read the source for w_scan how it does it
<br> eeprom has nothing to do with it
maury: so it is not stored on the hardware?
merbanan: but for atsc I would check all the frequencies that the spec would allow
<br> same for dvb-t/t2
maury: which is what us-ATSC-center-frequencies-8VSB is supposed to be
<br> but isn’t
merbanan: k, what was wrong with that file ?
maury: channels 2 to 6 are listed, but were sold off to cell phone companies several years ago
<br> same for everything from channel 50 to 69
<br> and channel 37 was never used
merbanan: ahh ok
maury: i believe it was close to the lyman alpha line
<br> so it made the radio astronomers pissed off
merbanan: well you can update it then
maury: ok done
<br> now, do I have to make an antirely new git repo and pull?
<br> or can I check into the repo that’s there?
merbanan: you need to post your patch to the mailing list
maury: hmmm
<br> ok noob at patches here, easy way to do with git?
merbanan: anyway you are correct in one observation the lists are often abit outdated
maury: i can fix
merbanan: http://git.schinagl.nl/cgi-bin/cgit.cgi/dtv-scan-tables.git/
<br> clone that and send the patch files to the mailing list
maury: i cloned already, and then added my Toronto file and then modified the “masterâ€
<br> so how do I generate the patch?
merbanan: git format-patch HEAD~1
maury: ok here goes...
<br> oh cool!
merbanan: I think you need to google what you need to add for generating proper git patches acceptable for linuxtv
maury: ok i will
merbanan: you need proper name and sob
maury: son of a bitch?
merbanan: :)
<br> signed of by
maury: ok
<br> do you know if “0001-dtv-scan-tables-update-dvb-s-Astra-28.2E.patch†makes sence for the patch? I see things that I did in in, but it seems I see others too which I did not do
<br> ahhh, it seems it added mine to Nick Morrott too
merbanan: you messed up your commit
<br> google is your friend
maury: yeah something odd
merbanan: gitk and inspect
maury: is that on linux?
merbanan: yes
maury: im on a mac
merbanan: it is available for mac also
maury: ill look for ports
<br> i think it just pointed to the wrong version
<br> oh i see, Nick was the last one to check in
<br> im reading the instructions. there is no way I can possiblt do that
<br> no wonder they are out of date! you need to be a kernel programmer to change a text file :-(
<br> git diff worked
merbanan: well I would say you need to be an experienced developer
maury: to edit a text file??!?!?
merbanan: to be able to jump through all the hops to get your changes merged upstream
<br> took me a month to get my changes though
maury: sure but I’m not making code changes
<br> this is basically documentation
<br> uggg. it says every single line is changed
<br> merbanan, still here?
merbanan: yaa
maury: can i send you my patch to look at?
merbanan: pastebin it
maury: hold...
<br> http://pastebin.com/JA53DsMb
merbanan: looks ok
<br> add -sob when you create the patch
maury: any idea why it says every line has changed?
merbanan: 1 file changed, 78 insertions(+)
<br> looks good to me
maury: ok up it goes!
***: awalls1 has left
<br> pocek has quit IRC (Ping timeout: 260 seconds)
<br> pmp has quit IRC (Ping timeout: 260 seconds)