Bug #5177
Weird stream encoding
0%
Description
Found some really odd encoding in recorded streams - please see attached media info.
Stream is 17.something seconds long, but the media info shows a video-length of 24:49:10 h; the offset into the streem (delay) is 24:48:53, so (lenght - delay) gives the correct running length. for the (2) audio streams the values are even more garbled.
You can get all the correct information from duration, delay, and "delay relative to ovideo" but the number are weird.
In consequence some (HW) decoders stumble, when palying those streams.
The "amcodec" used in Vero 4K won't synchronize correctly when skipping (ffd / bwd) within the stream.
The stream starts to play just fine, but when skipping synchronization is lost resulting in really bad video judder.
Problem seems to only show up, when AAC - or AAC_LATM - audio stream is recorded; with EAC3 audio at least everything's OK.
The .TS was recorded from German DVB-T2 (ARD bouquet (yes, it shows the ZDF label; but indeed is ARD)).
I'm not sure, whether this is encoded by Tvheadend or coming from the received transport stream.
This garbled encoding seems to also be used in the "htsp" stream profile (live TV) - at least the judder after skipping looks the same.
Files
History
Updated by Mathias Neuhaus about 6 years ago
Updated by This is the matching VERO issue ...
https://discourse.osmc.tv/t/stutter-frame-skipping/74211
Updated by saen acro about 6 years ago
Updated by Maby is connected with HW transcoding and B frames
General ID : 1 (0x1) Complete name : C:\Users\Saen\Desktop\ZDF-Morgenmagazin.ts Format : MPEG-TS File size : 7.31 MiB Duration : 17 s 178 ms Overall bit rate mode : Variable Overall bit rate : 3 503 kb/s Original network name : Astra Satellite Network 19,2'E Video ID : 341 (0x155) Menu ID : 1 (0x1) Format : HEVC Format/Info : High Efficiency Video Coding Format profile : [email protected]@Main Codec ID : 36 Duration : 24 h 49 min Width : 1 920 pixels Height : 1 080 pixels Display aspect ratio : 16:9 Frame rate : 50.000 FPS Standard : Component Color space : YUV Chroma subsampling : 4:2:0 (Type 0) Bit depth : 8 bits Color range : Limited Color primaries : BT.709 Transfer characteristics : BT.709 Matrix coefficients : BT.709 Audio #1 ID : 342 (0x156) Menu ID : 1 (0x1) Format : AAC Format/Info : Advanced Audio Codec Format profile : LC Muxing mode : LATM Codec ID : 17-2 Duration : 17 s 152 ms Bit rate mode : Variable Channel(s) : 2 channels Channel positions : Front: L R Sampling rate : 48.0 kHz Frame rate : 46.875 FPS (1024 SPF) Compression mode : Lossy Delay relative to video : -392 ms Language : German Audio #2 ID : 343 (0x157) Menu ID : 1 (0x1) Format : AAC Format/Info : Advanced Audio Codec Format profile : LC Muxing mode : LATM Codec ID : 17-2 Duration : 17 s 24 ms Bit rate mode : Variable Channel(s) : 2 channels Channel positions : Front: L R Sampling rate : 48.0 kHz Frame rate : 46.875 FPS (1024 SPF) Compression mode : Lossy Delay relative to video : -392 ms Text ID : 344 (0x158)-150 Menu ID : 1 (0x1) Format : Teletext Subtitle Language : German Other ID : 344 (0x158)-100 Menu ID : 1 (0x1) Format : Teletext Language : German Menu ID : 340 (0x154) Menu ID : 1 (0x1) Duration : 17 s 178 ms List : 341 (0x155) (HEVC) / 342 (0x156) (AAC, German) / 343 (0x157) (AAC) / 344 (0x158)-100 (Teletext, de) / 344 (0x158)-150 (Teletext Subtitle, de) Language : / German / / German / German Service name : Das Erste HD Service provider : ARD Service type : reserved for future use UTC 2018-08-14 03:30:00 : de:ZDF-Morgenmagazin / de:Moderation: Wolf-Christian Ulrich, Dunja Hayali und Mitri Sirin / news/current affairs / / 03:30:00 / Running UTC 2018-08-14 07:00:00 : de:Tagesschau / de: / news/current affairs / / 00:05:00 / Not running UTC 2018-08-14 07:05:00 : de:Live nach Neun / de:Raus ins Leben / news/current affairs / / 00:50:00 / rest of EPG is CUT
Updated by Mathias Neuhaus about 6 years ago
I suspect as much.
The decoder doesn't seem to find the I-frame / B-frame when skipping (or takes a B-frame for an I-frame).
Nevertheless the duration / delay encoding is garbled.
Updated by saen acro about 6 years ago
Keep in mind, that operator do not offer any time-shift optimisations.
So transcoding is 100% needed!