MKV playback slow/stuttering when file has high bitrate

flashi99 · November 3, 2018 at 7:00 PM

Hello,

I just installed the current stable release of LibreELEC [8.2.5] on my Raspberry Pi 3 B+, but I run into some issues with some if my files mainly when these videos have a very high bitrate.

It makes playback impossible as the audio plays normally and the timer runs correctly, but the video is very slow or stuttering.

I even tried the newest beta version of LibeELEC [8.90.006 ALPHA] as maybe the newer release of either KODI or LibreELEC may already had a fix for this, but the same problem occurs.

The video file is normally located on an SMB-share, but I tried NFS, as well as copying the file to a USB-Drive and directly attaching it to the RaspPie, it does not seem to matter from where I try to play the file. On my main system (Ubuntu 18.10, Intel i7 + GTX970) I have no issues playing the file in KODI or any other player.

Here is the mediainfo of the file I try to playback (This is an already cut file of the original MKV):

Code

General
Unique ID                                : 265220115529827420482072522571105701903 (0xC7878946B70369EB79DC83AC94BC100F)
Complete name                            : /home/User01/Desktop/No Game No Life - S01E01_cut60MB.mkv
Format                                   : Matroska
Format version                           : Version 4 / Version 2
File size                                : 56.9 MiB
Duration                                 : 22 s 500 ms
Overall bit rate mode                    : Variable
Overall bit rate                         : 21.2 Mb/s
Encoded date                             : UTC 2018-11-03 18:25:07
Writing application                      : mkvmerge v28.2.0 ('The Awakening') 64-bit
Writing library                          : libebml v1.3.6 + libmatroska v1.4.9
Attachments                              : AGRounded-Book.ttf / Arial Rounded MT.ttf / calibri.ttf / calibrib.ttf / GenBkBasR.ttf / Infinium Guardian.ttf / KGTurningTables.ttf / Mesouran_Serif_Black_SSi_Bold.ttf / OpenSans-Regular.ttf / OpenSans-Semibold.ttf / PFEASTASEVEN.TTF / Roboto-Medium.ttf / Roboto-MediumItalic.ttf / RussoOne-Regular.ttf / UNI0554.TTF

Video
ID                                       : 1
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : High 10@L5.1
Format settings                          : CABAC / 16 Ref Frames
Format settings, CABAC                   : Yes
Format settings, ReFrames                : 16 frames
Codec ID                                 : V_MPEG4/ISO/AVC
Duration                                 : 20 s 771 ms
Bit rate                                 : 20.2 Mb/s
Width                                    : 1 920 pixels
Height                                   : 1 080 pixels
Display aspect ratio                     : 16:9
Frame rate mode                          : Constant
Frame rate                               : 23.976 (24000/1001) FPS
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 10 bits
Scan type                                : Progressive
Bits/(Pixel*Frame)                       : 0.405
Stream size                              : 49.9 MiB (88%)
Title                                    : 01 - Beginner
Writing library                          : x264 core 133 r2334 a3ac64b
Encoding settings                        : cabac=1 / ref=16 / deblock=1:0:0 / analyse=0x3:0x133 / me=tesa / subme=11 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=24 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=0 / chroma_qp_offset=-2 / threads=12 / lookahead_threads=3 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=16 / b_pyramid=2 / b_adapt=2 / b_bias=0 / direct=3 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=23 / scenecut=40 / intra_refresh=0 / rc_lookahead=60 / rc=crf / mbtree=1 / crf=13.0 / qcomp=0.60 / qpmin=0 / qpmax=81 / qpstep=4 / ip_ratio=1.40 / aq=1:1.00
Language                                 : Japanese
Default                                  : Yes
Forced                                   : No

Audio
ID                                       : 2
Format                                   : FLAC
Format/Info                              : Free Lossless Audio Codec
Codec ID                                 : A_FLAC
Duration                                 : 20 s 821 ms
Bit rate mode                            : Variable
Bit rate                                 : 1 512 kb/s
Channel(s)                               : 2 channels
Channel positions                        : Front: L R
Sampling rate                            : 48.0 kHz
Frame rate                               : 11.719 FPS (4096 SPF)
Bit depth                                : 24 bits
Stream size                              : 3.75 MiB (7%)
Title                                    : Japanese 2.0
Writing library                          : libFLAC 1.2.1 (UTC 2007-09-17)
Language                                 : Japanese
Default                                  : Yes
Forced                                   : No

Text
ID                                       : 3
Format                                   : ASS
Codec ID                                 : S_TEXT/ASS
Codec ID/Info                            : Advanced Sub Station Alpha
Duration                                 : 20 s 360 ms
Bit rate                                 : 71.8 kb/s
Count of elements                        : 1355
Compression mode                         : Lossless
Stream size                              : 179 KiB (0%)
Language                                 : English
Default                                  : Yes
Forced                                   : No

Menu
00:00:00.000                             : :Intro

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If need be I could provide the first 22 seconds of the file so you could reproduce the issues yourself.

But I'd prefer to not post the link in a public forum, I could however PN the link.

Thanks in advance for the help

Cheers

**smp** · November 3, 2018 at 7:45 PM

Quote

Bit depth : 10 bits

Rpi does not hardware decode 10-bit video. You can still PM me the sample file so I will test it on my Pi.

flashi99 · November 3, 2018 at 9:24 PM

Hello,

thanks smp!

How could I possible miss that, you are right all problematic files are 10-bit.

I sent you the link to the file in any case as I would like to know how well it works for you.

I will probably re-encode my files to 8bit.

Regards

**smp** · November 3, 2018 at 9:49 PM

It is unwatchable here too. Kodi falls back to software decode but Rpi3 is not fast enough to decode this in software.

flashi99 · November 3, 2018 at 10:21 PM

Thought as much.

Thanks for testing!

**chewitt** · November 4, 2018 at 1:35 PM Official Post

It's not a problem specific to RPi devices. The H.264 standard specifies 8-bit content so while it's technically possible to rip media into a 10-bit version of the format, nobody makes GPU/SoC chips that support it and all devices CPU decode it. Most Anime fans end up migrating to Intel NUC's (or similar x86_64 boxes) because lots of CPU grunt is needed to decode with all the fancy GPU based video post-processing that the Anime scene seems to like.