[solved] DVB-T2 Recordings: Sometimes no Audio after muxing with mkvmerge (1 Viewer)

bta489

Portal Pro
March 17, 2013
127
64
Germany Germany
Country flag
Hi there,

I have a strange problem with mkvmerge when processing some recordings from german DVB-T2.

So what's happening:
I record a show on my HTPC. I access the recordings from a different PC to Remux it to MKV, remove unwanted tracks and cut off the beginning and the end with mkvmerge. This usually works fine for me. However on some recordings the remuxed file will not play any audio or won't play at all (it stays on the start frame). The Raw recorded .ts-file plays without problems.

When I just remux a problematic file (keep all tracks, no edits whatsoever), the beginning will play fine up to the program announcements, when the sound cuts out, and the video continues silently. Sometimes the sound returns for the next program at the end of the recording. This appears to be limited to recordings from DasErste/ARD and related channels.

When comparing the MediaInfo of both files there are some differences in Bitrate and Codec-ID:
The Raw recording:
Code:
Audio #1
ID                          : 64 (0x40)
Menu ID                     : 137 (0x89)
Format                      : AAC LC
Format/Info                 : Advanced Audio Codec Low Complexity
Muxing mode                 : LATM
Codec ID                    : 17-2
Duration                    : 41 min 53 s
Bit rate mode               : Variable
Maximum bit rate            : 262 kb/s
Channel(s)                  : 6 channels
Channel layout              : C L R Ls Rs LFE
Sampling rate               : 48.0 kHz
Frame rate                  : 46.875 FPS (1024 SPF)
Compression mode            : Lossy
Delay relative to video     : -873 ms
Language                    : German
The edited MKV:
Code:
Audio
ID                          : 2
Format                      : AAC LC
Format/Info                 : Advanced Audio Codec Low Complexity
Codec ID                    : A_AAC-2
Duration                    : 25 min 56 s
Bit rate                    : 124 kb/s
Channel(s)                  : 6 channels
Channel layout              : C L R Ls Rs LFE
Sampling rate               : 48.0 kHz
Frame rate                  : 46.875 FPS (1024 SPF)
Compression mode            : Lossy
Delay relative to video     : 15 ms
Stream size                 : 23.0 MiB (5%)
Language                    : German
Default                     : Yes
Forced                      : No
Has anyone encountered a similar problem or even has a fix?
 

Paul Shirley

Portal Pro
November 3, 2008
68
3
Country flag
I have probably the same problem with UK Freeview HD. What's happening is the sound track changes format between stereo and 5.1 during the recording. Most tools detect the sound at the video start, not the cut point and throw away everything else.

You need to do a .ts to .ts cut at the point the sound track changes format before converting to any other format. I use H264TS_Cutter.exe, using the mouse scroll wheel to scrub through seems to get the position right more often. Sorry, you'll have to search for it.

If anyone has a better fix, I'll be a happy bunny to hear it.
 

bta489

Portal Pro
March 17, 2013
127
64
Germany Germany
Country flag
That seems likely.

I tried the h264 ts cutter (found here) and it sort of works with HEVC/x265. The Preview has problems decoding the image, but if you know the area where to cut you can find a place. I had to change the settings (as a dialogbox suggested) to I-Frames as Cut-In-Points and All-Frames as Cut-Out-Points or else the program would crash.
The processed file however plays fine, and that is what counts. At least there is a way to process these problematic files.
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

OP Similar threads Forum Replies Date
N [solved] How to record a series (UK Freeview dvb-t) General 10
R Suggestions for reliable PCIe DVB-S2 tuner MediaPortal 1 Talk 8
Golf4 DVB-IP über Fritzbox - m3u-Senderliste Allgemeines Support- und Diskussionsforum 33
M TV Server can't tune to some DVB-S multiplexes while other software can General 0
C Telenet analog-to-digital switch -- manually finding and inputting DVB-C channels in Mediaportal2 General 0
framug No color in TVGuide when XMLTV without DVB EPG MediaPortal 1 Talk 59
T [solved] Any idea where Channel 107 (DVB-T2) BBC News HD (and others!) have gone??? Installation, configuration support 12
framug [EPG] Some problems with DVB EPG Improvement Suggestions 49
badboyxx TV card is listed as unknown in TV-server config General 4
bribbon [Pending] Switzerland: DVB-T switch-off on 03 June 2019 Submit: EPG-Grabbers and tuningdetails 0
bribbon [Pending] DVB-C Tuning Parameters: Switzerland.UPC Cablecom [NID 43020] v.7.xml Submit: EPG-Grabbers and tuningdetails 0
J DVB-S2 card fails to tune? Subchannel count increasing Television (MyTV frontend and TV-Server) 3
D Cannot get a fully populated UK Freesat EPG (DVB-S) General 14
hanfmaster Dvb-s2 zu android ipad Einsteigerforum 0
C DVB-C Empfänger Hauppauge Win TV dual wird in Media Portal nicht aktiviert TV / Streaming 1
Terra [solved] MP TV Server cannot find any channels anymore, DVB viewer works Installation, configuration support 8
Booner [Verkauf] Verkaufe Max S8 8 Tuner DVB-S2 Karte von Digital Devices neuwertig Marktplatz 2
N What dvb-t/t2 dual or quad tuners work with media portal (in the UK)? Newcomers Forum 8
E [solved] Vodafone Kabel dvb-c Braunschweig Tuning Liste (Stand 31.01.2019) TV / Streaming 0
items [Verkauf] Hauppauge Dual TV Tuner USB DVB-C, DVB-C Marktplatz 0
A Help! MP2 - DVB-T Not recognised (DRIVERS?) General 12
porky996t DVB Sat card possibly failed General Support 1
splatterpop My optimized dvb epg configuration for tv server MediaPortal 1 Talk 0
N Tswriter Watch / Listen Media 51
A Genpix skywalker dvb card not scanning channels 1.19 0
Similar threads

























Top Bottom