Problems playing GoPro home movies [SOLVED]

[vinomarky]

Hi,

All my 1080p GoPro videos play quite poorly with MrMC, with significant buffering issues

I have a gigabit back-end to my NAS (wired connection to ATV4), and from reading some previous posts have tried turning on hardware acceleration, as well as sync to display option. Have also tried wireless just for giggles - no change. I'm connecting to a Synology NAS via Samba, but have previously tried NFS as well without improvement.

The MediaInfo is as below for a short sample, which I have also uploaded as a sample - Its just a short video to save download size. The longer videos are often worse;
https://www.dropbox.com/s/3aksc24mohwcp ... 1.MP4?dl=0

Would aprpeciate any thoughts as to how to sort

Thanks,

Mark

General
Complete name : C:\Users\vinom\Dropbox\Public\GOPR0141.MP4
Format : MPEG-4
Format profile : Base Media / Version 1
Codec ID : mp41 (mp41)
File size : 47.2 MiB
Duration : 8 s 768 ms
Overall bit rate mode : Variable
Overall bit rate : 45.1 Mb/s
Encoded date : UTC 2017-04-23 13:00:43
Tagged date : UTC 2017-04-23 13:00:43
AMBA : x

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : [email protected]
Format settings, CABAC : Yes
Format settings, ReFrames : 1 frame
Format settings, GOP : M=1, N=13
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 8 s 760 ms
Bit rate mode : Variable
Bit rate : 45.0 Mb/s
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 25.000 FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.868
Stream size : 47.0 MiB (100%)
Title : GoPro AVC
Language : English
Encoded date : UTC 2017-04-23 13:00:43
Tagged date : UTC 2017-04-23 13:00:43
Color range : Full
Color primaries : BT.709
Transfer characteristics : BT.709
Matrix coefficients : BT.709

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : 40
Duration : 8 s 768 ms
Bit rate mode : Constant
Bit rate : 128 kb/s
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 48.0 kHz
Frame rate : 46.875 FPS (1024 spf)
Compression mode : Lossy
Stream size : 137 KiB (0%)
Title : GoPro AAC
Language : English
Encoded date : UTC 2017-04-23 13:00:43
Tagged date : UTC 2017-04-23 13:00:43

Other #1
ID : 3
Type : Time code
Format : QuickTime TC
Duration : 8 s 760 ms
Title : GoPro TCD
Language : English
Encoded date : UTC 2017-04-23 13:00:43
Tagged date : UTC 2017-04-23 13:00:43

Other #2
Type : Time code
Time code of first frame : 13:00:53:13
Time code, striped : Yes
Bit rate mode : VBR

[cosmoxl]

sorry for your troubles.

I downloaded the test file you have there and it plays on my system quite smoothly.

I confirmed that videotoolbox does indeed decode it and I'm using sync to display.

I played it from my plex library and the actual file was on a network drive.

Edit:

I also played it via NFS and it also plays fine after a little blip early to wait on audio and video queues to fill up.

There is something weird about the file that's causing MrMC to not fill up a cache (forward: 0B). I tested other files via NFS and Plex and they fille up cache just fine. So, maybe that's part of the problem.

[davilla]

Something strange with these files, even under a dev OSX setup and using sw FFMpeg has non-smooth playback. Here I have tons on ponies to handle decoding. Looking deeper.

Try this, start playing, once started, bring up OSD and do a seek to beginning, that's the << at very left. See what that does for you ?

[davilla]

sorry for your troubles.

I downloaded the test file you have there and it plays on my system quite smoothly.

I confirmed that videotoolbox does indeed decode it and I'm using sync to display.

I played it from my plex library and the actual file was on a network drive.

Edit:

I also played it via NFS and it also plays fine after a little blip early to wait on audio and video queues to fill up.

There is something weird about the file that's causing MrMC to not fill up a cache (forward: 0B). I tested other files via NFS and Plex and they fille up cache just fine. So, maybe that's part of the problem.

The sample is quite small, pretty much fits in deuxer buffers so forward: will also show zero.

[vinomarky]

Thanks for looking into this guys!

I can confirm that trying to arrow left to get to the start of the video does little to improve things. Using the far left arrow from the OSD interface appears to improve things slightly - at first it looks like it does nothing (just the stuttering buffering), but after a few seconds the video does eventually play through - something which it didnt do before.

Have uploaded a slightly larger sample to test (note may take a few minutes to upload, so if you jump on this straight away and its not there you know why);
https://www.dropbox.com/s/s3rd0r6nr5kuc ... 5.MP4?dl=0

I have this issue not only with GoPro video, but also similar behavior with some purchased HD video content. The solution I've generally been adopting is to re-encode to H264 (high quality settings - keeping same framerate etc) with Handbrake which pretty well keeps the quality and allows it to play buttery smooth, but is a pain to do for each file... Its strange, because the original contenct is generally H264 or X264 to start with...

Regs,

Mark

[davilla]

as cosmoxl stated, the sample seems to play fine from a Plex server. No blip at start. Note this is direct play so no transcoding. Very odd.

[vinomarky]

In case it adds some useful context - the videos that I have issues with generally play just fine if I load them into iTunes, and play through 'Computers' connection in ATV (ie outside of MrMC). Incidentally (and probably unsuprisingly), I generally have the same stutering issues with Kodi or InFuse with these problem videos.

[davilla]

think I found/fixed it.

[vinomarky]

Awesome! - Many thanks

Will wait impatiently for next update then

[davilla]

Well, too quick on the draw it seems, BUT I think I understand better what is going on.

The files play perfectly fine when local. We do our heavy dev under OSX desktop. If the file is on disk, it plays perfectly fine, if the file is on a SMB mount, skips and blips at the beginning. Running under a 200MB cache and enabling all file systems for cache, better but still has startup issues.

The issue is with the container and how the GoPro sets that up. For some reason, the demuxer does a big seek, well past the actual file length. SMB seek stalls, and you get delays in fetching data. When local, the big seek fails right away.

Looking deeper.