[mythtv-users] Jason Beck's QAM guide Now on the Wiki

[R. G. Newbury]

I understand that you should have an atscscrid entry for HD channels but 
nothing for SD channels.
I presume that you ran a channel scan (again) in mythtv-setup for that 
change to have occurred.



Noah Markon wrote:
> Interesting, my atscsrcid for some of my HD stations have changed from
> NULL back to some numbers.
>
>   
>> Ok I just thought I'd report back on what happened. I tried both, cat
>> /dev/dvb... and mplayer /dev/dvb.. and they both seemed to work ok on
>> the SD channels. It's a little hard for me to tell since I don't get
>> any sound on my server, and I don't know how to run the second command
>> over a network, or output the video into a file then view it on a
>> faster machine.  However I did not encounter any slow-motion in the
>> video.
>>     
You should get sound at least on the SD channels. Your physical setup 
may mean that you don't but if you have a sound card in the box, you 
should get output, which you can send to an amplifier etc. But check 
that your sound stuff is working and the volume turned up. I had to 
fiddle with this a number of times, as it was a little flakey at first. 
It eventually remembered its state and came back from reboot as it had been.

>> I tried running the HD channel that was causing my frontend to crash,
>> and I get the following ( i edited out some stuff)  errors when I
>> played through mplayer:
>> mplayer /dev/dvb/adapter0/dvr0 -vid 16 -aid 17 -vo x11 -geometry 800x600
>> a52: CRC check failed!
>>     
Interesting that you get this error (too). I get this with SD channels. 
Since this is a straight recording, I have no idea where/how it derives.

>> VDec: vo config request - 1920 x 1080 (preferred csp: Planar YV12)
>> VDec: using Planar YV12 as output csp (no 0)
>> Movie-Aspect is 1.78:1 - prescaling to correct movie aspect.
>> VO: [x11] 1920x1080 => 1920x1080 Planar YV12
>> SwScaler: using unscaled Planar YV12 -> BGR 16-bit special converter
>> a52: CRC check failed!   -0.377 ct: -0.050  16/ 16 56% 23% 47.6% 0 0
>> <--I got a ton of these.
>>
>> Too many video packets in the buffer: (140 in 8397293 bytes).
>> Maybe you are playing a non-interleaved stream/file or the codec failed?
>> For AVI files, try to force non-interleaved mode with the -ni option.
>> A:88217.3 V:88217.6 A-V: -0.324 ct:  0.448 209/209 39% 22% 75.5% 45 0
>>
>>     
You are playing a non-interleaved stream at this point, so try the '-ni' 
option.

>> I then tried some of the other HD channels that have been working, and
>> they each have the same type of errors, so I'm guessing the problem is
>> related to my slow server. However that' just a guess.
>>
>> Ok since these channels work fine when i tune them through the azap
>> methods, but they don't when I tune them in myth, where does that
>> leave me? What are my next steps to try?
>>     
You have confirmed that you can record a program 'natively' from the 
/dev socket tuned by azap.
You have condirmed that you can extract an SD stream from the total 
stream ( using the -vid and -aid parameters).
Your scan (channel.conf) results give you the frequency, vid, aid and 
the serviceid for the digital channels you can receive.

If you have built your dtv_multiplex table (enter frequency, note the 
mplexid) and entered the mplexid and serviceid for good channel into the 
channel table, then you should be able to receive that channel in 
mythtv... But note that this will only work if the default channel is 
set validly. And you may not be able to tune  up and down in live tv if 
there are 'bad' channels in between. You should be able to 'jump' using 
the guide and you should be able to record.

Your HD problem is different. clearly you are receiving an HD stream, 
but the hardware does not like it much. You may want to try downloading 
and installing an HD capable version of xine, to see if it can deal with 
what you have. (Offhand I do not know if mplayer will do HD levels..)

I presume that your video output hardware will actually handle the 
1920x1080 video stream.

Geoff






 

       R. Geoffrey Newbury			
     Barrister and Solicitor
 Suite 106, 150 Lakeshore Road West
    Mississauga, Ontario, L5H 3R2

  905-271-9600  Fax 905-271-1638
       newbury at mandamus.org