Wrong frequencies in DVB-C-channels.conf, but scan log shows correct frequencies

[carsten1212]

I am sure I can try bookworm. I will do later. It is most probably a bug id that Library, a docker with tvheadend on the same machine works flawlessly.

Keep you posted when I was able to do it, mayve tomorrow MESZ.

Carsten.

[mvallevand]

You don't need the full bookwork just that library. Maybe TVHeadend uses the older dvb libraries.

Martin

[carsten1212]

@Martin, the quick shot doesn't work as libdvb5-1.22.1-5+b2 is compiled with libc-2.34 whereas my current Debian
has libc-2.31-14+deb11u6 installed. Not worries, I will create a bootable bookworm USB stick tomorrow
to give it a try.

Good night,
Carsten.

[mvallevand]

Ok, it is easy to build master.  You can try this, which is newer than bookworm and save time if you choose. I have a feeling we will need the full mux.

Martin

[carsten1212]

Good Morning Martin,

was that a master version that you compiled for bullseye? Nevertheless, it will not correct the problem.

Also bookworm live USB with  libdvb5-1.22.1-5+b2 has the same issue.

I will need to work a bit for money now. Right afterwards I will look at the code of dvbv5-scan, as I am
curious about the fact that it logs the right frequencies but doesn't write them.

Example:

Code:

Scanning frequency #1 330000000
Sperre (0x1f) Signal= -22,00dBm C/N= 38,96dB UCB= 11
Dienst BR Fernsehen Süd HD, Anbieter ARD: reserviert

Code:

[BR Fernsehen Süd HD]
    SERVICE_ID = 10325
    NETWORK_ID = 41030
    TRANSPORT_ID = 23
    VIDEO_PID = 5201
    AUDIO_PID = 5202 5203 5207 5206 1570 5205 5209
    PID_0c = 1076
    PID_0b = 5275 2171
    PID_06 = 5204
    FREQUENCY = 4294967293
    MODULATION = QAM/256
    INVERSION = AUTO
    SYMBOL_RATE = 6899978
    INNER_FEC = NONE
    DELIVERY_SYSTEM = DVBC/ANNEX_A

Carsten.

[mvallevand]

Yes that was master so newer than bookworm. As I noted if you can send a link to the file was the full mux I can try and see what dvbv5-scan is doing and load it here with debugging on.

Martin

[carsten1212]

OK Martin, I captured with bullseye and master library, although I don't think it's a difference:

Code:

LD_LIBRARY_PATH=~/libdvb5/test-master dvbv5-zap -c channels.conf Das\ Erste\ HD -P -t 60 -o fullmux.ts
using demux 'dvb0.demux0'
reading channels from file 'channels.conf'
service has pid type 06:  5104
tuning to 330000000 Hz
pass all PID's to TS
  dvb_set_pesfilter 8192
dvb_dev_set_bufsize: buffer set to 6160384
Sperre (0x1f) Signal= -22,00dBm C/N= 39,21dB UCB= 11
Sperre (0x1f) Signal= -22,00dBm C/N= 35,98dB UCB= 11
Record to file 'fullmux.ts' started
received 381534720 bytes (6209 Kbytes/sec)
Sperre (0x1f) Signal= -22,00dBm C/N= 38,90dB UCB= 11

You find the two files on google drive:

https://drive.google.com/file/d/1TlSAkk5...sp=sharing
https://drive.google.com/file/d/1XFrnxMQ...sp=sharing

When I want to do my own tests, I have to install the required building tools, git clone and that's it, right?

Carsten.

PS: Sperre is another weird German translation of "locked". I make another proposal for translation when
we have fond the bug that is causing this issue here :-).

[mvallevand]

Thanks.

That translation is in the dvb source probably a pot file not related to NextPVR.

Martin

[carsten1212]

Martin, I did a scan with enabled -v option and recognised (when I interpret correctly, as I am not an expert on DVB) that
all the other muxes that he found and ignored as I also gave the -F option were correctly identified with their frequency.
I attached the log.

BUT: in at the start it said:

Code:

Scanning frequency #1 330000000
FREQUENCY = 330000000
MODULATION = QAM/256
INVERSION = AUTO
SYMBOL_RATE = 6900000
INNER_FEC = NONE
DELIVERY_SYSTEM = DVBC/ANNEX_A
Parameter für DVBC/ANNEX_A bekommen:
FREQUENCY = 4294967293
MODULATION = QAM/256
INVERSION = AUTO
SYMBOL_RATE = 6900033
INNER_FEC = NONE
DELIVERY_SYSTEM = DVBC/ANNEX_A

So after "Parameter für DVBC/ANNEX_A bekommen:=Have got the parameters for DVBC/ANNEX_A:" are the wrong values.
So the code is somehow post processing what it finds in de-WillyTel and then the mess start. Maybe this helps a bit to find 
the right place. 

Carsten.

[carsten1212]

I know already where it is happening but I don‘t understand the code good enough to know what it is for.

It will overwrite frequency and symbol rate in dvb-fe.c:772 in function call

Code:

dvb_fe_store_parm(&parms->p, fe_prop[i].cmd, fe_prop[i].u.data);

Carsten.