Unable to FF MKV movies

Why is it that on some movies I am unable to FF or select early chapters without the WDTV restarting from the very beginning.

I can select say chapter 3 (if the intro credits are too long) and when I hit enter, the movie restarts. The same goes if I FF through opening credits, when I hit play the movie restarts.

This only happens on certain movies although they are all ripped with MakeMKV. Any reason why this happens, please?

The files either lack a proper index, or they lack proper sequence headers.

Most likely, it’s a lack of sufficient sequence headers… if it had no indexing at all, you’d get the “Trick Mode Not Supported” message when you try to fast-forward.

You’ll have to re-encode them.

Can you add a mediainfo Log because i do have the same fast forwarding issues with some WMV HD Movies.

Even if its not the same Media inside the container  i guess it would help the developers more to see what kinda

Codecs / Bitrates you are using in the MKV which trouble :slight_smile:


Important would be everything except the Videotitle and other unneccesary Infos like coding dates …

===================== General =====================
Complete name               : Z:\Comedy\Ruthless People (1986)\Ruthless People (1986).mkv
Format                      : Matroska
File size                   : 3.59 GB
Duration (ms)               : 1h 30mn
Total bitrate               : 5 698 Kbps
Encoded date                : UTC 2011-02-17 12:53:04
Encoded application         : MakeMKV v1.6.3 win(x86-release)
Encoded library             : libmakemkv v1.6.3 (0.7.7/0.8.1) win(x86-release)

===================== Video =====================
Id                          : 1
Format                      : MPEG Video
Format version              : Version 2
Format profile              : Main@Main
Format settings - BVOP      : No
Format settings - Matrix    : Default
Codec Id                    : V_MPEG2
Codec info                  : MPEG 1 or 2 Video
Duration (ms)               : 1h 30mn
Bitrate mode                : Variable
Bitrate                     : 5 201 Kbps
BitRate_Nominal/String      : 6 956 Kbps
Width                       : 720 pixels
Height                      : 576 pixels
Aspect ratio                : 16:9
Framerate                   : 25.000 fps
Standard                    : PAL
Colorimetry                 : YUV
Colos space                 : 4:2:0
Bit depth                   : 8 bits
Scan type                   : Interlaced
ScanOrder/String            : Top Field First
Bits/(Pixel*Frame)          : 0.502
Stream size                 : 3.28 GB (91%)
Language                    : English

===================== Audio =====================
Id                          : 2
Format                      : AC-3
Format info                 : Audio Coding 3
Format settings mode extens : CM (complete main)
Codec Id                    : A_AC3
Duration (ms)               : 1h 30mn
Bitrate mode                : Constant
Bitrate                     : 384 Kbps
Channel(s)                  : 6 channels
ChannelPositions            : Front: L C R, Side: L R, LFE
Sampling rate               : 48.0 KHz
Bit depth                   : 16 bits
Stream size                 : 248 MB (7%)
Title                       : 3/2+1
Language                    : English

===================== Text =====================
Id                          : 3
Format                      : VobSub
Codec Id                    : S_VOBSUB
Codec info                  : The same subtitle format used on DVDs
Language                    : English

===================== Menu =====================
00                          :00:00.000                     : en:Chapter 01
00                          :08:18.600                     : en:Chapter 02
00                          :13:12.800                     : en:Chapter 03
00                          :22:16.200                     : en:Chapter 04
00                          :31:33.600                     : en:Chapter 05
00                          :41:57.880                     : en:Chapter 06
00                          :46:27.480                     : en:Chapter 07
00                          :50:56.480                     : en:Chapter 08
00                          :56:40.616                     : en:Chapter 09
01                          :07:53.376                     : en:Chapter 10
01                          :14:32.696                     : en:Chapter 11
01                          :24:29.376                     : en:Chapter 12
01                          :30:09.336                     : en:Chapter 13

Playback can only start at the closest sequence header.

On a stock DVD, this isn’t an issue, because the sequence headers are half a second apart, so you can start “anywhere” within the video stream within a half-second accuracy.

Other encodes have longer sequences between headers.  Some PVR files have only one header for the entire file – they can’t be FF at all – they can only be played from the beginning.

Files encoded with Handbrake, for example, have the headers about 5 seconds apart, on average.  So even if the chapter information contains the exact frame that chapter is supposed to start at, when you actually select that chapter, playback starts at the nearest header – either a couple of seconds before, or a couple of seconds after the actual time the chapter is coded for.  There’s no way to force playback to begin at the exact frame specified, unless it happens to also be the start of a sequence.

Some other encoders can create even longer sequences.  Many use a GOP length of 300 frames, and then group several GOPs into one sequence… playback can be 10 minutes off from where you expect it to be.  This leads to odd quirks like pressing fast-forward for a few seconds, and when you press play again, the playback begins 5 minutes before you pressed fast-forward.

Thank you for the very professional reply RoofingGuy. I am unfortunately a long way behind you in technical know-how. If I understand you correcetly, this is an issue with certain DVD’s and not an encoding or WDTV issue. And as such it is something I cannot do anything about - not that it’s a big deal anyway - and it would not make any difference if I was to use another codec, ripping method or file format. Is that the case?