jerky playback of M4Vs on Roku

[bcm00re 18]

I have some old TV shows that play jerky on Roku -- but not on Android or on a PC (using Emby in a browser).  The files are already mpeg4 format and play without transcoding.  They were originally recorded using WMC using an old HDHR tuner, and I likely used MCEbuddy to re-encode them.  They are only around 2 Mbps so it is not a bandwidth issue.  Furthermore, back when they were originally recorded/re-encoded I swear they played back fine on Roku (with MediaBrowser running WMC server). 

 

I have attached a log file that includes me playing first on Roku and then on my PC.  I have tried playing on an Express+ and Primere (both wifi) as well as a Roku 3 (wired ethernet) and get the same results on all three.

embyserver - Copy.txt

[speechles 1917]

I am guessing these mpeg4 inside m4v are Xvid/Divx?

 

If so, this is because the mpeg4 encoder technically supports them they do introduce some oddball side effects at times. We do have a way to help you already in the app when these things occur.

 

Right now this is only available in the Emby Beta app. Look for a little graphic equalizer button, has 3 sliders showing. Click that and when the menu appears, choose Playback Correction. If this solves it, great. If not, press Playback Correction again and again until it finally plays correctly. Once you get to full blown transcoding and have used the button the maximum amount of times possible the Playback Correction will disappear from the menu. This is normal. Once you get to full transcoding this will solve any problem. It may not be required to do full transcoding to get your desired effect. Simply remuxing and using Playback Correction once may be all you need. But you can use it multiple times if you need to if you have media that is stubborn to play correctly.

[bcm00re 18]

Media Info

VideoTitle720P H264

CodecH264

Codec tagavc1

AVCYes

ProfileConstrained Baseline

Level32

Resolution1280x720

Aspect ratio16:9

AnamorphicNo

InterlacedNo

Framerate59.94006

Bitrate1777 kbps

Bit depth8 bit

Pixel formatyuv420p

Ref frames1

NAL4

AudioTitleEng AAC stereo Default

Languageeng

CodecAAC

Codec tagmp4a

ProfileLC

Layoutstereo

Channels2 ch

Bitrate159 kbps

Sample rate48000 Hz

DefaultYes

Containermov

PathE:\processedTV\Modern Family\Modern Family-S07E04-She Crazy.m4v

[bcm00re 18]

I don't see what you are talking about in Emby Beta 3.0.119.  I didn't see it when I had the show selected or in the Settings.  Where can I find it exactly?

[speechles 1917]

Play the item as normally you do and start the Video Player. Wait until you see the issue. Press OK to bring up on the Video Player OSD overlay. On this OSD is a little graphic equalizer button with the 3 sliders. This is the button you need to click.

 

I forgot to mention this is directly within the video player. When you see the issue, you can fix it within the video player without having to leave. Use the Playback Correction button. Let us know what you think. Thanks.

 

EDIT: It might be the level32 at 60fps making it weird. Using Playback Correction multiple times might be required. You can use Playback Correction more than once. How many times you can use it depends on the play method the player decided to start at which depends entirely on the capabilities of the Roku device.

Edited November 7, 2018 by speechles

[bcm00re 18]

I think it did the trick -- thanks for the info! I did take it to the max. This fix should be all I need since this appears to only be an issue on old recordings, and I'll eventually watch and delete all of them.

[bcm00re 18]

EDIT: It might be the level32 at 60fps making it weird.

So what does level 32 mean?

[speechles 1917]

So what does level 32 mean?

 

http://help.encoding.com/knowledge-base/article/do-you-have-any-information-on-h-264-levels/

 

level 3.1 and level 3.2 have weird effects on certain Roku models. Never could determine any underlying way to detect videos with these issues. This is why the Playback Correction button is so critical and important to have. Without it there were videos we could not play properly. With it there is nothing we cannot play.

[bcm00re 18]

I need to make a correction: this problem does NOT occur when using a Roku 3 (but does with a Primiere and Express+). So it seems like it is only with newer Roku hardware. Perhaps that tidbit can help someone better understand why/how this happens.

[Happy2Play 8242]

I need to make a correction: this problem does NOT occur when using a Roku 3 (but does with a Primiere and Express+). So it seems like it is only with newer Roku hardware. Perhaps that tidbit can help someone better understand why/how this happens.

Do they have different firmware?

[bcm00re 18]

All three are on 8.1.0 but each one does have a different build number.

[bcm00re 18]

Also, taking a closer look today, I see the Playback Correction feature doesn't really fix the problem. It appears to make things somewhat smoother though. I think the other night when I first tried it my brain just got a little used to the jerkiness, but today after viewing it on the Roku 3 I had a good baseline to judge against. I then tried playing with the resolution settings in the Beta. Going to 480p with a max bitrate of 4 Mbps did not fix things, but using 720p with a max bitrate of 1.5 Mbps did.

[speechles 1917]

You can use the Playback Correction button several times if the first time doesn't solve it. It will eventually get to full transcoding of the video stream and the Playback Correction button will disappear.

 

Conversely, using the resolution/quality menu will force a transcode if you pick a low enough bitrate. When it does transcode it will use the resolution you told it. So you can choose 720p or 480p in 1.5mbit and one will be higher resolution with some possible artifacting, the other lower resolution with less or no artificating.

 

This gives you much greater control over playback than ever before.

[bcm00re 18]

You can use the Playback Correction button several times if the first time doesn't solve it. It will eventually get to full transcoding of the video stream and the Playback Correction button will disappear.

 

That is the odd thing, I used it until it was gone and the jerkiness still existed (but it did seem to be lessened). I tried two different Roku models too.

 

Conversely, using the resolution/quality menu will force a transcode if you pick a low enough bitrate. When it does transcode it will use the resolution you told it. So you can choose 720p or 480p in 1.5mbit and one will be higher resolution with some possible artifacting, the other lower resolution with less or no artificating.

 

The thing I found odd was that the problem persisted when I tried 480p @ 4mbps. Being the source is 720p @ 1.77mbps, I expected that to force a transcode and clear up the problem, but it did not. I selected 720p @ 1.5mbps and that did fix all the jerkiness (and created some artifacting but I find it less annoying than the jerkiness). Edited November 7, 2018 by bcm00re

[bcm00re 18]

I tried my older Roku Express model and it did not have the problem. It is also connected via Wifi so I can confirm it is not a wired vs. wireless connection issue.

 

Details on models without the problem:

Express		3700X		8.1.0		4155-28
3               4200X           8.1.0           4145-04

Details on models with the problem:

Express+	3910RW		8.1.0		4500-51
Premiere        4620X           8.1.0           4159-29

Edited November 8, 2018 by bcm00re