TV recording issue (1 Viewer)

[marttoma]

MediaPortal Version: 1.7.0

Description
I have 4 channels DBV Cine C/T card from Digita Devices with 1 common CAM module. Only DBV-C TV cards are selected as enabled in MP TVConfig Tool. The CAM module is shared by all 4 cards - see attached print screens. Just 3 TV cards are set up in MP TVConfig Toll in "Recording" tab for recording (1 TV card is dedicated for TV watching all time).

Please note the my TV signal strength (~95-99%) and quality (~85-95%) are fine as I have cable TV at home - I checked also by MP.

Issue #1: MP1 does not record TV channels properly - in case of multiple channel recording 2 channels are recorded properly and the 3rd channel not -> its files size is 10x less as it should be and it can not be replayed properly (MP stops to play such TV recorded file within 10-15 min - even the duration in recorded xml file shows 90 min) the whole as MP does not record whole time period of the 3rd selected TV channel.
Note: I think this issue was already in MP 1.7.0 pre-release.

Issue#2: Even I have just 3 TV cards set up for TV recording (to keep 1 TV card for watching), I can set up more than 3 TV channels in EPG for recording in one time.
TV cards I have do not support multichannel recording within one multiplex as far as I know, so I think I should not be able to select more than 3 TV channels for recording in one time.
Note: I think this issue was already in MP 1.7.0 pre-release.

Steps to Reproduce:
Start MP, set up in EPG 3 different TV programs to record in same or similar time (to be sure all 3 TV channels will be recorded simultaneously), to send HTPC to sleep mode, after the recording has finish to wake up HTPC and to check recorded TV channels - it such way I can be reproduce the issue - 1 channel is not recorded properly.

 

[mm1352000]

Hello

Issue #1: MP1 does not record TV channels properly - in case of multiple channel recording 2 channels are recorded properly and the 3rd channel not -> its files size is 10x less as it should be and it can not be replayed properly (MP stops to play such TV recorded file within 10-15 min - even the duration in recorded xml file shows 90 min) the whole as MP does not record whole time period of the 3rd selected TV channel.
Note: I think this issue was already in MP 1.7.0 pre-release.

MP is recording for the whole time period. However, MP is not receiving a clean stream from the tuner. There are many continuity errors in the TsWriter log, which means that parts of the stream are lost. This explains the small file size.

Are you sure that your CAM is capable of decrypting 3 channels simultaneously?
Which CAM have you got?

Aside from the CAM, it is possible that the problem is caused by stress on the recording hard drive.
Do you use MS Security Essentials or Windows Defender or some other security software?
Please use task manager > performance tab > resource monitor to check the processes using the HDD when recording 3 channels.

Issue#2: Even I have just 3 TV cards set up for TV recording (to keep 1 TV card for watching), I can set up more than 3 TV channels in EPG for recording in one time.

It is not possible to restrict TV Server to only use a tuner for timeshifting or recording.
The setting that you've found means that if TV Server fails to start recording with a tuner then it will only retry with X other tuners. It does not prevent TV Server from using all 4 tuners for recording.

TV cards I have do not support multichannel recording within one multiplex as far as I know, so I think I should not be able to select more than 3 TV channels for recording in one time.
Note: I think this issue was already in MP 1.7.0 pre-release.

Your tuners do support multi-channel recording for free (not encrypted) channels. The limit is one channel per tuner for encrypted channels. So assuming your CAM supports it, you can record/timeshift at least 4 channels. You can record/timeshift more than 4 channels in the case where the channels are not encrypted and the channels are broadcast in the same multiplex/frequency.

Regards,
mm

 

[marttoma]

MP is recording for the whole time period. However, MP is not receiving a clean stream from the tuner. There are many continuity errors in the TsWriter log, which means that parts of the stream are lost. This explains the small file size.
Are you sure that your CAM is capable of decrypting 3 channels simultaneously?
Which CAM have you got?
Aside from the CAM, it is possible that the problem is caused by stress on the recording hard drive.
Do you use MS Security Essentials or Windows Defender or some other security software?
Please use task manager > performance tab > resource monitor to check the processes using the HDD when recording 3 channels.

Thanks to your feedback I found out HW issue few minuted ago, let me check this issue again. Yes, I am sure my CI Module can decode 4 channels simultaneously as it is special feature of Digital Devices cards (the CI module can decode same number of TV channels as you have TV cards, but only under Windows).
The CAM I have is Conax. BTW, is Conax supported by MP? I did not check it.

It is not possible to restrict TV Server to only use a tuner for timeshifting or recording.
The setting that you've found means that if TV Server fails to start recording with a tuner then it will only retry with X other tuners. It does not prevent TV Server from using all 4 tuners for recording.

I am confused here. The description for the settings probably confused me (http://wiki.team-mediaportal.com/1_...guration/TV-Server_Configuration/07_Recording):
Recording
Maximum free cards to try
Defines the maximum numbers of tv cards to use for recordings. For example if you have 4 tv cards and set this value to 3 you can be sure to always have at least 1 tv card free for live TV.

Does it mean e.g. in my case of 4 TV tunners there is no way to reserve 1 TV tunner for watching? Is there any setting where is possible to define what has than priority - i.e. planned recording or TV watching?

Your tuners do support multi-channel recording for free (not encrypted) channels. The limit is one channel per tuner for encrypted channels. So assuming your CAM supports it, you can record/timeshift at least 4 channels. You can record/timeshift more than 4 channels in the case where the channels are not encrypted and the channels are broadcast in the same multiplex/frequency.

I am sorry, I mean my TV card does not support multichannel decoding - see http://wiki.team-mediaportal.com/1_MEDIAPORTAL_1/13_Setup_Guides/2_TV_Setup/0_TV_Card_Features
and DBV-C part (first line in the table is about Digital Devices& CINE CT TV card type). I would like to be sure I understand properly - my TV channel cards support multichannel decoding for free channels, right?
In this case I understand the MP can allow me to set up more TV channels (if they are transmitted within same multiplex as others TV channels, which are selected to be recorded). But, is there any verification in MP (like it is in MCE) to monitor max limit of recording channels? Or does it mean I can set up how many I want and MP will record just what is technically possible? What is then the rule for TV channels selection for the recording (if the MP allows to set up more recorded TV channels as it is technically feassible)?

 

[mm1352000]

marttoma, I think you're confused again.

Yes, I am sure my CI Module can decode 4 channels simultaneously as it is special feature of Digital Devices cards (the CI module can decode same number of TV channels as you have TV cards, but only under Windows).

I know that DD hardware supports this, but the CAM also has to support it.
If you have a CAM that can only decrypt one channel then it can only decrypt one channel, end of story. It would not matter if you linked it to four tuners. Still it would only decrypt one channel.
So, again I ask:

Are you sure that your CAM is capable of decrypting 3 channels simultaneously?
Which CAM have you got?

The CAM I have is Conax.

I'm asking for the vendor (eg. TechniSat) and model details please.

BTW, is Conax supported by MP? I did not check it.

Conax, Irdeto, Nagra... has nothing to do with MP. It has to be compatible with the CI slot and driver.

I am confused here. The description for the settings probably confused me (http://wiki.team-mediaportal.com/1_...guration/TV-Server_Configuration/07_Recording):
Recording
Maximum free cards to try
Defines the maximum numbers of tv cards to use for recordings. For example if you have 4 tv cards and set this value to 3 you can be sure to always have at least 1 tv card free for live TV.

The description is misleading. This setting is only a limit for the number of tuners to try. TV Server only needs to try more than one tuner in the case where a recording fails to start on the first tuner.

Does it mean e.g. in my case of 4 TV tunners there is no way to reserve 1 TV tunner for watching?

Yes.

Is there any setting where is possible to define what has than priority - i.e. planned recording or TV watching?

Yes, here:
http://wiki.team-mediaportal.com/1_...n/TV-Server_Configuration/10a_User_Priorities

Set the priority for the scheduler (user used for recording) lower than the priority for all other users except the EPG grabber.

I am sorry, I mean my TV card does not support multichannel decoding - see http://wiki.team-mediaportal.com/1_MEDIAPORTAL_1/13_Setup_Guides/2_TV_Setup/0_TV_Card_Features
and DBV-C part (first line in the table is about Digital Devices& CINE CT TV card type).

Please read the explanation of the feature.
http://wiki.team-mediaportal.com/1_...m/01_Supported_TV_Cards#Multichannel_Decoding

I would like to be sure I understand properly - my TV channel cards support multichannel decoding for free channels, right?

Yes, all tuners do.
As the description says:

Multichannel decoding is the ability to decrypt multiple channels from a single transponder/multiplex with a single tuner.

If the channel does not have to be decrypted then multichannel decoding is not relevant (decoding = decrypting).

In this case I understand the MP can allow me to set up more TV channels (if they are transmitted within same multiplex as others TV channels, which are selected to be recorded). But, is there any verification in MP (like it is in MCE) to monitor max limit of recording channels?

Sorry, I don't understand what you mean by "max limit of recording channels" and I don't understand why you'd want to monitor it.

Or does it mean I can set up how many I want and MP will record just what is technically possible?

Yes, MP will do what is technically possible.
The constraints are:

1. You can disable tuners to prevent TV Server from ever using them.
2. You can set the priority order for the tuners.
   
3. You can prioritise timeshifting or recording.
4. You can set the limit on the number of channels that TV Server can decrypt with the tuner.

This should be enough to get the best possible results from the available tuners.

What is then the rule for TV channels selection for the recording (if the MP allows to set up more recorded TV channels as it is technically feassible)?

TV Server will record the program/channel that starts first.

 

[marttoma]

I'm asking for the vendor (eg. TechniSat) and model details please.

OK, I see, sorry. The vendor is SMIT (see: http://www.upc.cz/televize/Prijimaci-zarizeni-digitalni-televize/ca_modul/). I have sent question to UPC regarding to this CAM - how many channels it can decrypt simultaneously.

 

[Vasilich]

@marttoma
on DD website your CAM is listed as supporting only 2 transponders(in your case - tuners) decryption simultaneously http://support.digital-devices.de/knowledgebase.php?article=27&language=English

 

[mm1352000]

on DD website your CAM is listed as supporting only 2 transponders(in your case - tuners) decryption simultaneously http://support.digital-devices.de/knowledgebase.php?article=27&language=English

...and that would explain the problem very nicely.

 

[marttoma]

Are you sure that your CAM is capable of decrypting 3 channels simultaneously?

From DD web pages it looks the CAM can do just 2 channels simultaneously

From my trial it looks it can decode 2, but as you can see below, I would not know about this limitation from MP:

Trial set up - 1 encrypted channel per 1 multiplex:
1) I removed Microsoft antivir MS Essential (it was source of some disc performance delay during the recording) -> so NO antivir SW during the trial
2) I set up OS (Windows 7) on 1st SSD disk
3) I set up TV recording directory to the 2nd standard magnetic disc
4) I set up RAM disc and I set up timeshift to this RAM disc (just 1 GB of RAM from 8GB for RAM disc)
5) I restarted Windows and I started MP
6) I switch on TV
7) I found out which channels are really encrypted in each multipex (I removed the CAM card from CI interface in order to check if the channel is really encrypted)
8a) then I jump on 1st encrypted channel on 1st multiplex (so I saw the TV screen) and then I started to record this 1st channel (on 1st multiplex)
8b) then I jump on 2nd encrypted channel on 2nd multiplex (so I saw the TV screen) and then I started to record this 2nd channel (on 2nd multiplex)
8c) then I jump on 3rd encrypted channel on 3rd multiplex (so I saw the TV screen) and then I started to record this 3rd channel (on 3rd multiplex)
8d) then I jump on 4th encrypted channel on 4th multiplex (so I saw the TV screen) and then I started to record this 4th channel (on 4th multiplex)

As you can see, I was able to jump during the recording to any TV channel without any message/warning I am run out of the CAM decrypting limits.
During the recording only TV recording was active on my 2nd standard magnetic disc.

When I check the recording, I discover that:
9a) 1st channel was recorder only limited time (probably by time, when I jumped to the 3rd channel)
9b) 2nd channel was recorded only limited time (probably by time, when I jumped to the 4th channel)
9c) 3rd channel was recorded also shortly (insted of 5 min just 45sec -> no idea why)
9d) 4th channel was recored proper time without any problems

Conclusion:
1) yes, my CAM is probably limited to 2 decrytping channels in one time
2) MP does not displea any message/warning that the user is out of CAM decrypting limits -> it can be
3) MP does not care about remaining free CAM decrypting resources (and user does not know about this as well) - during 2 decrypted recording channels user can jump to any TV channel to see 3rd decrypted channel which leads to break recording of the 1st decrypted channel.[DOUBLEPOST=1398380498][/DOUBLEPOST]

The description is misleading. This setting is only a limit for the number of tuners to try. TV Server only needs to try more than one tuner in the case where a recording fails to start on the first tuner.

What is the benefit to set up less number of TV cards than the maximum number? I dont understand, what is the logic behind it.[DOUBLEPOST=1398381039][/DOUBLEPOST]

Please read the explanation of the feature.
http://wiki.team-mediaportal.com/1_...m/01_Supported_TV_Cards#Multichannel_Decoding

Thank you for this link. In my case I have 4 TV cards and 1 common CI interface, but my CAM can support only 2 channels.
Anyway MP does not display any message/warning when user wants to record (lets estimate user is already recording 1st TV channel from 1st multiplex) 2nd TV channel within the 1st multiplex if the TV card does not support multichannel decoding -> MP allows to start this 2nd TV recording but it should not.[DOUBLEPOST=1398381297][/DOUBLEPOST]

Sorry, I don't understand what you mean by "max limit of recording channels" and I don't understand why you'd want to monitor it.

This is the functionality, which is I think missing in MP - to not allow o user or to display message/warning, if user wants to record something and there are not available resorces - like in my trial I described above.

 

[mm1352000]

From my trial it looks it can decode 2, but as you can see below, I would not know about this limitation from MP

But MP has no way to know this either (so we can't tell you) except if you start timeshifting/recording and suddenly another timeshift/record session becomes encrypted... and by then it is too late - the recording is ruined. We expect you to know the limits of your hardware - tuner, CI and CAM - and configure TV Server properly. There is no way for us to do this automatically for you.

As you can see, I was able to jump during the recording to any TV channel without any message/warning I am run out of the CAM decrypting limits.

That is because you linked the CI/CAM to all four tuners and configured the CAM limit as 1 for each tuner. This means that TV Server will think you can decrypt 1 + 1 + 1 + 1 = 4 channels, 1 with each tuner. In other words, TV Server is not configured correctly.

The CAM limit in TV Server is the limit for the tuner not the CAM. This is no problem for most tuners because they don't support MTD (CAM sharing). However, with MTD you have to do things differently.

The way to configure your setup correctly is to:

1. Use the DD software to link the CI/CAM to only two tuners.
2. Disable CI/CAM support (untick "CAM enabled and present...") for the two tuners not linked to the CI/CAM: http://wiki.team-mediaportal.com/1_...nfiguration/02_TV_Servers#Edit_Tuner_Settings
3. Unmap the encrypted channels from the two tuners not linked to the CI/CAM: http://wiki.team-mediaportal.com/1_...Server_Configuration/03_TV_Channels/2_Mapping
4. Prioritise the tuners not linked to the CI/CAM above the tuners that are linked.

Why do we do it this way?
It is currently the only way to enforce the CAM limit for DD MTD.
Step 1 and 2 ensure that TV Server knows it can't use 2 tuners to decrypt any channels.
Step 3 ensures that TV Server won't try to decrypt channels with tuners that can't decrypt them.
Step 4 ensures that TV Server maximises your ability to record/timeshift encrypted channels. It will use the tuners that can't decrypt for free channels and only use the tuners that can decrypt when it really has to.

PS: TVE 3.5 will allow you to configure the limit for the CAM rather than for the tuner. This would also solve your problem. TVE 3.5 is currently only available for MP2 ("native TV").

1) yes, my CAM is probably limited to 2 decrytping channels in one time

I agree.

2) MP does not displea any message/warning that the user is out of CAM decrypting limits -> it can be

MP can't and won't display any message/warning because (a) it can't detect that a channel changes from decrypted => encrypted and (b) you have configured TV Server to think that your tuners can decrypt 4 channels (so TV Server didn't think you reached the limit yet).

3) MP does not care about remaining free CAM decrypting resources (and user does not know about this as well) - during 2 decrypted recording channels user can jump to any TV channel to see 3rd decrypted channel which leads to break recording of the 1st decrypted channel.

MP does care and will prevent exceeding the decrypt limit/resources, but you have to configure it correctly. When you tell TV Server that each of your 4 tuners can decrypt 1 channel it thinks: 1 + 1 + 1 + 1 = 4 channels can be decrypted. It has no way to know that the CAM is shared.

What is the benefit to set up less number of TV cards than the maximum number? I dont understand, what is the logic behind it.

I think that setting actually also affects timeshifting. Trying each tuner can take a long time - maybe 20 seconds or more, depending on configuration. If you have 4 tuners and all of them are failing it might take 80 seconds or more (!!!) for a tune request to fail. During that time MP is unresponsive and appears frozen. The setting is available to reduce the number of tuners to try => reduce the unresponsive/frozen time.

Thank you for this link. In my case I have 4 TV cards and 1 common CI interface, but my CAM can support only 2 channels.
Anyway MP does not display any message/warning when user wants to record (lets estimate user is already recording 1st TV channel from 1st multiplex) 2nd TV channel within the 1st multiplex if the TV card does not support multichannel decoding -> MP allows to start this 2nd TV recording but it should not.

I think you're not right.
Assuming both channels are encrypted, MP will only allow the second recording with the same tuner if the CAM limit is set to 0 (unlimited) or >= 2 (which means the tuner can decrypt 2+ channels).

This is the functionality, which is I think missing in MP - to not allow o user or to display message/warning, if user wants to record something and there are not available resorces - like in my trial I described above.

One last time: MP has no way to know the limits of the CAM except by the configuration that you supply.

 

[Vasilich]

MP has no way to know the limits of the CAM

agree.
@marttoma the info on DD website came out of experience / tests, there is NO way to ask CAM how many transponders it can decrypt.