Seek Entries at End of MKV File Instead of at Start, Impossible to Navigate

[koberulz]

I created an MKV file and put it on my Emby server. Sat down to watch it. Missed something, tried to use the 'skip back' function to go back ten seconds. Nothing happened. I tried the 'skip forward' button. Also no response. Chapter skipping doesn't work either. I backed out, and then went back into it via the 'resume' button...and it started from the beginning.

Using MKVToolnixGUI's Info Tool, I see 'Seek head' listed all the way down the end of the list, after all the clusters. There's a 'Seek head' entry at the start as well, but it only has one Seek Entry. The one at the end has five.

What's going on here?

Video came out of Premiere Pro as a lossless AVI file and an ac3 file. AVI into MeGUI to create a .264 file, mux with MKVToolnix, add chapters with MKVToolnix.

MediaInfo:

General
Format                                   : Matroska
Format version                           : Version 4 / Version 2
File size                                : 10.6 GiB
Duration                                 : 3 h 16 min
Overall bit rate                         : 7 743 kb/s
Encoded date                             : UTC 2020-01-21 13:56:07
Writing application                      : mkvmerge v40.0.0 ('Old Town Road + Pony') 64-bit
Writing library                          : libebml v1.3.9 + libmatroska v1.5.2

Video
ID                                       : 1
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : High@L4.1
Format settings, CABAC                   : Yes
Format settings, ReFrames                : 4 frames
Codec ID                                 : V_MPEG4/ISO/AVC
Duration                                 : 3 h 16 min
Bit rate                                 : 7 397 kb/s
Width                                    : 720 pixels
Height                                   : 480 pixels
Display aspect ratio                     : 4:3
Frame rate mode                          : Constant
Frame rate                               : 29.970 (30000/1001) FPS
Standard                                 : NTSC
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : MBAFF
Scan type, store method                  : Interleaved fields
Scan order                               : Top Field First
Bits/(Pixel*Frame)                       : 0.714
Stream size                              : 10.1 GiB (96%)
Writing library                          : x264 core 157 r2969 d4099dd
Encoding settings                        : cabac=1 / ref=5 / deblock=1:0:0 / analyse=0x3:0x113 / me=umh / subme=8 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=12 / lookahead_threads=2 / sliced_threads=0 / slices=4 / nr=0 / decimate=1 / interlaced=tff / bluray_compat=1 / constrained_intra=0 / bframes=3 / b_pyramid=1 / b_adapt=2 / b_bias=0 / direct=3 / weightb=1 / open_gop=1 / weightp=0 / keyint=30 / keyint_min=1 / scenecut=0 / intra_refresh=0 / rc=cqp / mbtree=0 / qp=23 / ip_ratio=1.40 / pb_ratio=1.30 / aq=0
Default                                  : Yes
Forced                                   : No
Color range                              : Limited
Color primaries                          : BT.601 NTSC
Transfer characteristics                 : BT.601
Matrix coefficients                      : BT.601

Audio
ID                                       : 2
Format                                   : AC-3
Format/Info                              : Audio Coding 3
Mode extension                           : CM (complete main)
Format settings, Endianness              : Big
Codec ID                                 : A_AC3
Duration                                 : 3 h 16 min
Bit rate mode                            : Constant
Bit rate                                 : 192 kb/s
Channel(s)                               : 2 channels
Channel positions                        : Front: L R
Sampling rate                            : 48.0 kHz
Frame rate                               : 31.250 FPS (1536 spf)
Bit depth                                : 16 bits
Compression mode                         : Lossy
Stream size                              : 269 MiB (2%)
Title                                    : Dolby Digital 2.0
Language                                 : English
Default                                  : Yes
Forced                                   : No

Menu
00:00:00.000                             : :Chapter 1
00:30:26.325                             : :Chapter 2
00:37:10.895                             : :Chapter 3
00:47:05.690                             : :Chapter 4
00:48:16.827                             : :Chapter 5
00:50:39.336                             : :Chapter 6
01:06:33.723                             : :Chapter 7
01:07:58.274                             : :Chapter 8
01:30:24.753                             : :Chapter 9
01:34:30.231                             : :Chapter 10
02:03:13.119                             : :Chapter 11
02:07:34.480                             : :Chapter 12
02:37:15.860                             : :Chapter 13
02:38:32.703                             : :Chapter 14

[sneaker]

That's the default file layout mkvmerge produces.
https://mkvtoolnix.download/doc/mkvmerge.html#mkvmerge.file_layout

[koberulz]

So does that mean the seek entries being at the end aren't the problem? Why is this file impossible to navigate then?

[sneaker]

The problem likely isn't the file but Emby. Make sure you are running the latest version. If you still have problems I would ask the Emby devs. Google brings up several hits for "emby mkv seeking". (I don't know anything about Emby myself.)

https://emby.media/community/index.php?/topic/80231-playback-issue-mkv-files/

[koberulz]

The Emby devs are the ones that pointed me in the direction of the end-of-file seek headers.

[jagabo]

Have you tried remuxing with MkvToolNix(GUI)?

[sneaker]

The Emby devs are the ones that pointed me in the direction of the end-of-file seek headers.

Link to your thread on the Emby forum?

[koberulz]

Have you tried remuxing with MkvToolNix(GUI)?

That's how I muxed it the first time, why would doing it again be any different?

[koberulz]

https://emby.media/community/index.php?/topic/78889-unable-to-resume-film-or-start-fro...chapter/page-1

[sneaker]

Did you add the chapters using the "Multiplexer" tool ("Output" tab) or via the "Chapter editor"?

[koberulz]

Chapter editor.

[sneaker]

Try via "Multiplexer"->"Output" tab instead (or remux after adding the chapters as suggested by jagabo). The 2 ways to add chapters can result in different file layouts. (Whether or not that works around your problem is a different question.)



P.S.: 16 reference frames for 720x576 is perfectly within H.264 High Profile level 4.0.

[koberulz]

Yep, simply remuxing seems to have remedied the issue.

[jimjulian]

The issue is in the EBML header's seekhead entries. Mkclean, part of matroska.org resources, can correct the problem. Mkvinfo can list the results. Mkvalidator is also available.