H264 playback jerky - How to improve?

It's indeed too CPU-intensive. The Flash plugin isn't very good in terms of playback performance. There are a couple of ways to speed this up:

1. Set the flashvar 'smoothing=false'. This'll disable the smoothing filter. The video will look less good, but perform better.
2. Use a smaller video even, for example on of 236px wide (exactly 1/3 of the 708px display).

Are there any other way around the videos not playing smoothly as I would like to playback the videos in 708x480 size if possible?
Are there any updates in the pipeline that would make the playback less CPU intensive?
What about using another Flash Plugin?
Thanks for any help.
Hugh

Hi Jeroen
I see in another post you say
"The jerky fullscreen playback is because it's too processor-intensive for the player to play the video fluently. I'm working on support for the new hardware-accelerated playback, which'll resolve this. Will be in the next release (4.0)."

Any idea when release 4.0 will be ready?
Cheers
Hugh

The problem is indeed the CPU intensity, for example flowplayer only uses 50% CPU when playing H264 movies. But they use a different smoothing. Because the JWplayer gives smoother quality but uses 100% CPU and then it stotters.

So if you can find a way to reduce the CPU usage with JW player you also fix this bug. Or adobe should release a fix for the cpu usage of the flash plugin. Firefox can work a little bit better with flash but not good enough.

Jeroen, are you going to optimise the player so it will be less CPU intensive. Because then we will be able to stream fullscreen video (or larger resolution like 640x480) in H264 without stottering video?

I think there must be a way to make the player less CPU intensive. I read something about a new flash function that can render with the videocard of the client instead of the CPU when using fullscreen. Maybe you can implement that and maybe adobe already expanded that function so you can always use the videocard instead of the CPU.

But I think that less CPU is also a good goal for a next version!

You can use the two flashvars 'smoothing' and 'deblocking' to set a playback lower quality. Set 'smoothing' to 'false' and 'deblocking' to 1,2 or 3. That should help a lot in terms of playback speed.

The 4.0 will arrive around april 1st, but the hardware scaling in there only applies to fullscreen mode!

Thanks for responding Jeroen.

I know about smoothing disable. Deblocking I didn't know. But I would like to keep the good quality. So if you can think of something to keep the quality and lower the CPU usage. That would be great.

Second I hope Adobe will make a way to use hardware scaling in all modes, because video rendering on CPU only is nasty. Maybe they will find a solution or you can think of a hack to use normal video mode and let adobe think you are using fullscreen?

I also noticed that firefox works better then IE when rendering video and using less CPU.

I'm also very interested in getting this tearing issue resolved, I'll try these deblocking things and smoothing and report back on what I found worked for us.

Any word on a date for 4.0? Changelog?

Mac OSX 10.4.11
Safari 3.0.4
JW Media Player 3.16
G5 Dual 2.7 Ghz

Video "elephants" at the end of the playlist
(640x480, h.264 wrapped mp4, encoded in mpeg streamclip).

weggli-tv.com/web/player2.html (deblocking = 1, smoothing = false)
weggli-tv.com/web/player.html (smoothing and deblocking not in the embeded code)

The presence of the flashvars smoothing (set to false) and deblocking (set to 1) makes no difference
(there is also no apparent improvement in the quality of the image)
With and without them I get about 2 multiple-Frame-dropouts within one minute of the video playing.

Mac OSX 10.3.4
Safari (the one which came with the release of 10.3.4)
JW Media Player 3.16
G4 Dual 1 Ghz
Geforce 4

Video "elephants" at the end of the playlist.

weggli-tv.com/web/player2.html (deblocking = 1, smoothing = false)
weggli-tv.com/web/player.html (smoothing and deblocking not in the embeded code)

The presence of the flashvars smoothing (set to false) and deblocking (set to 1) make no difference.
Fullscreen or not: The Video plays back with about 3 frames/second.

If it is not an issue of the to old software (sorry I am not able to update it right now)
I think even the G4 should be able to play the video fluently.

@Serge - you dont tell which version of flash plugin you have in the browsers (could be the crucial factor! - currently v.9.0.115)

adobe flash versiontest: http://www.adobe.com/go/tn_15507
adobe flash uninstall: http://www.adobe.com/go/tn_14157
adobe flash install: http://www.adobe.com/shockwave/download/index.cgi?P1_Prod_Version=ShockwaveFlash

@Andersen - on both Macs it is v.9.0.115

On the G4, I made the test again with all the software up to date:
Mac OSX 10.4.11
Safari 3.1
JW Media Player 3.16
Flashplayer 9.0.115
G4 Dual 1 Ghz

there is no change to what I discribed above with the older system and browser
(The presence of the flashvars smoothing (set to false) and deblocking (set to 1) makes no difference.
Fullscreen or not: The Video plays back with about 3 frames/second).

In addition on the same mac I tested my video in iTunes,
which is known to use also a lot of the cpu:
The test-video plays 25 fps in fullscreen with no stuttering at all.
Also the videos of my podcast, which are encoded with the same settings
play online in Safari/QuickTime and iTunes just as they should...

In my ("selfmade" and dropped) player, which has no smoothing at all:
weggli-tv.com/test/
I thought it plays videos in fullscreen hardware accelerated (as a basic feature of the video object)
but my test-video also does play just about 3 fps (on the G4 Dual 1 Ghz).

Is it possible that the flashplayer really uses such a lot more cpu than for example iTunes does?

The video on the Bits on the run page is converted at a bitrate of 1080Kbps. That's pretty high, if you have a massive amount of visitors its more interesting to do video's on a bitrate between 250 and 500. Because bandwidth isn't very cheap. So the best result would be if we can stream videos at a bitrate between 250 and 500 Kbps and have smoothing and deblocking on and no jerking.

It''s a hard goal to reach but if Adobe or Jeroen can make it work it would be a big improvement.

@JeroenW

The controllbar was blurry/enlarged when I made my tests (on both Macs)
The bitrate of my video "elephants" is about 1450 kBit/s

I checked "elephants dream" at your Bits on the Run page:

Mac OSX 10.4.11
Safari 3.0.4
JW Media Player 3.16
G5 Dual 2.7 Ghz
Flashplayer 9.0.115

CPU usage:
One of the cpu works about 1/3, the other at about 2/3.

Video:
There are rarely some dropped frames, if you don't look for them, you won't see them.

Mac OSX 10.4.11
Safari 3.0.4
JW Media Player 3.16
G5 Dual 2.7 Ghz
Flashplayer 9.0.115

CPU usage:
One of the cpu works about 1/3, the other at about 2/3.

Video:
There are rarely some dropped frames, if you don't look for them, you won't see them.

Mac OSX 10.4.11
Safari 3.1
JW Media Player 3.16
Flashplayer 9.0.115
G4 Dual 1 Ghz
Geforce 4

CPU usage:
One of the cpu works about 1/2, the other at about 5/4.

Video:
When I first played "elephants dream", I would say it had a framerate below 8 fps.
The second time the video plays nearly as well as on the G5 Mac.
There might be a lower framerate, but not really that one can see it.
Multiple dropped frames are just as rare as on the G5.

Because of the new results with "elefants dream" I tested my own video on the G4 again.
I don't know why but:

My video weggli-tv.com/web/player2.html (the video elephants at the end of the playlist)
(1450 kBit/s, 640x480, encoded in mpeg streamclip as h.264 wrapped in mp4) really uses a lot more CPU.

G4 Dual CPU usage:
One of the cpu was allways at 100%
The other was really lower and never at the maximum.

As mentioned above the video just plays with about 3 fps.

I don't know if there is a problem about how the flashplayer uses Dual CPUs.
If both would be used equally, then the video might play better.
Maybe this is a Dual CPU Mac issue?

Apparently the flashplayer has also trouble with some encoders:
In my playlist there are older videos which were encoded in QuickTime.
For example "atelier101-Ansichten #2", (iPod export preset, 1600kBit/s, 640x480, h.264 wrapped in m4v)
It plays with nearly no dropped frames on the G4...

JeroenW, is it possible to tell which software you used to encode "elephants dream" at your Bits on the Run page?

I see that "elephants dream" is a flv-video,...
But still there is a very big difference in framerate between encoded h.264/mp4 videos
in QuickTime or MPEG Streamclip.

I don't know if it is an issue about data peaks or keyframes.
The QuickTime (single pass) iPod-Export preset has nearly no data peaks,
probably because of that, videos exported in this way play so well in the flashplayer on my Dual G4 1Ghz.

On the other hand, my h.264/mp4 videos, exported from MPEG Streamclip, play really badly: 3fps on my Dual G4 1Ghz,
although they are also single pass encoded and do have a lower datarate (just 1450 kBit/s compared to 1600 kBit/s of the QuickTime iPod exports).

My problem is, that I don't like the overall quality of the QuickTime h.264/m4v iPod Export
(for 1600 kBit/s the image quality should be better...)

Maybe the next versions of the flashplayer will be more flexibel in playing h.264/mp4 videos exported from different software...
At the moment I am afraid (if you don't have a high end PC / Mac)
there is no proper solution for a smooth playback of 640x480, h.264 videos in any
Flashplayer based media player.

@Coen: if you want to stream at 400kbps I think you should use a 320px wide movie and not larger. You'll get better results by scaling these up than by encoding 720px wide videos to 400kbps.

@Serge: indeed, it is the VP6 version. Dumb of me, let me make sure the H264 is streamed in there as well. In the wizard, there is already a setup with 720px wide H264 file (the "MP4 with FLV fallback" example).

Bits on the Run uses Mencoder for the H.264 conversion - dual pass variable bitrate. I think the variable bitrate might be an issue indeed since the CBR-Quicktime video plays better. Also there's the 'complexity' setting of H264 that might be an issue here.

Can you check if the H264 example from the wizard plays back better? If not, it might be worth doing some tests with different H264 encoding settings.

Overall I'm afraid you are right. Flash + H264 is not really suited for older computers.

So here again:

Mac OSX 10.4.11
Safari 3.1
JW Media Player 3.16
Flashplayer 9.0.115
G4 Dual 1 Ghz
Geforce 4

Video: Setup Wizard/ Mediaplayer with MP4 file and FLV fallback.

The duration of the video is quite short, so if it was longer, the playback might get even better after some time (?)
On the G4 I mainly see occasional dropped frames and stuttering in the high movements scenes. Compared to my QuickTime iPod export videos, your video does play a little less smooth, but it is still a lot better than my MPEG Streamclip exports.

I wanted to integrate my h.264/mp4 podcast videos on my website with the JW Media Player.
Now there is this issue, that if vistors are using a two years old not top of the line PC/Mac
to playback real high quality (multipass, b-frames,...) videos, they will see no smooth playback
and leave my website...

On the same PCs/Macs, the same videos play absolutely fine,
if they are watched in Quicktime or iTunes...

I just wonder, if Adobe realizes that they really should work on
the high CPU usage of their flashplayer while playing back h.264 videos.

It really does not make sense to integrate h.264 playback, if 50% of the viewers
just see stuttering videos...

Does anybody know, if the developers at Adobe at least consider this as a bug?

Comparing a FLV to the same H.264 video (same size, framerate, keyframes, fps, etc.) I see a size reduction of about 6:1 and a CPU usage reduction of 50% for the H.264 video.

So maybe consider that you are trying to push too much quality, resolution, framerate, etc. out to users who aren't ready for it and have a lesser quality, but still H.264 as your fallback. They will still get some of the quality benefits, but their CPU will be able to handle it.

Flash has always been, and probably always be, a CPU hog, just like Windows. It keeps the folks at Intel in business making ever faster CPUs, which quickly become obsolete and have to be replaced with 8-core 5gHz power hungry monsters just to handle crappy video.

(YouTube is going to H.264, so the users will upgrade their hardware quickly enough.)

I´m encoding videos with this settings:

Encoder software: MEGUI (x264)
Baseline: HQ Slowest
Bitrate: 336kbps video + 64kbps audio (aac)
Res: 512x384
0.5 second interleaving

In my computer all run smooth and fine, and, in general, all the guys with a 2 years old PC and a adsl band >= 4000 kbps seen all smooth and fine too. But I would like to optimize my settings for playback in only >=1000 kbps, a more popular bandwidth
What should I change? Res? Bitrate? Baseline? Interleaving? All?

First try things that won't affect the quality too much.

framerate 20
keyframes every 2-3 seconds

Then maybe the bitrate.

Then finally, if you have to, the size.

Keep in mind that if Flash has to re-size the video on the client, CPU usage skyrockets. So, always make your JW FLV Media Player's display area is the same size as your video. Don't overstretch/re-size — ever!

Thanks, Ajax. All my encodes are 25 fps, 250 keyframe. I will try with 75 keyframe.

There are some things happening that I don´t understand. I have encoded a video in FLV, with Adobe Flash CS3 video encoder, On2 Vp6. 400 kbps. 512x384. People with 1000-2000K of bandwith have no problem to play this. Not jumps, not dropped frames. The same video encoded with Megui (HQ slowest) in h264 stops and play constantly. Is the same bitrate! And the CPU is not the basic problem in this case. I´m trying with ("bufferlength","15"), not succes. What happens? Beseline problem? Keyframe problem?

@Ajax: Thank you for your recommendations.

Fact is:
I can watch my TV-quality h.264/mp4 640x480px / 25fps videos in fullscreen
(encoded in MPEG Streamclip, multipass, b-frames, deinterlaced)
on my seven years old G4 Digital Audio, 466 Mhz without any dropped frames.

As long as I use QuickTime, I can do that.
On the other hand the same video plays less smooth on my G5 Dual 2.7 Ghz
if I watch it in the flashplayer (newest update...).

So this comparison really questions my plans to integrate my podcast-videos
in a flashplayer on my website.

Fact is:
If you use QuickTime, Realplayer, Windows Mediaplayer or whatever,
SD videos generally just play smooth on even quite older PC/Macs...

I believe that there are many users who don't like to buy every two years a new PC,
especially if they have to do this just to be able to watch the same videoquality in flash,
which was played smoothly by the other players for years...

I am afraid if you want 80% of your website visitors to be able to watch your
videos in TV-quality, you won't use the flashplayer for the next two or three years.

@Serge,

Since we're dealing with facts now!

Fact is:

Flash, since its beginning, has been a CPU/resource hog and probably always will be.

Fact is:

The penetration rate of the Flash Player is 90%+.

Fact is:

Everyone that I know is happy with the YouTube quality because, "It's the content quality, NOT the video quality, that matters." A funny clip is still funny in low-quality video. A dumb, boring clip is still dumb and boring in wide-screen H.264.

Fact is:

The way people are using media is changing. They are now "sipping", their media (watching/listening to short clips rather than long, boring, drawn-out, dumb, un-funny................).

@Ajax

I agree with you: the content matters and there are masses watching low-fi short-clips on Youtube.
The question is if those low-fi shortmovies really will replace television which is moving towards
high definition at the moment.

I am maybe to old to spend hours watching shortclips on youtube.
For me the technical quality of those clips equals the quality of the content...

To me this interacting-thing can be quite tiring - I mean, do you really can sit
back and relax when you have to decide which movie you want to see after 2 minutes?

I rather like to watch a documentary or a good movie without interruptions,
broadcasted/streamed in the quality as the makers wanted me to see it.

A flash spread over 90% doesn't help if the flashplayer can't play simple SD videos on
I am afraid about 50% of the PCs/Macs...

If you want to put your podcast-videofiles somehow emedded on your website,
you shouldn't be forced to encode everything again (and add more gigs to your server)
just because mp4 intergration in flash means 10 times more CPU usage than in the other mediaplayers.

I mean it is just amazing that my Mac G4 466 seems to play my videos in QuickTime smoother
than my G5 Dual 2.7 Ghz in the flashplayer.

Without video I never had any problems with the flashplayer even on quite old PCs/Macs.
It is just this video integration...

They are advertising the new flashplayer for hdtv playback.
I am afraid, you need something like a rendering farm, to get a smooth playback of hd-videos in
the flashplayer.

@Ajax:
Sorry for my statement above - there is certainly also good content on sharing-platforms like Youtube.

Hi,

It is always that I have to wait for my computer to download the video (HD), before the video actually starts ?
www.videodev.fr/test/HD4quartvlongue

I do not have this problem with a much longer and much bigger video, encoded with Flash Media Encoder (SD).

Thanks for your help.

@Jean-Sam:
Before exporting the movie you should check "fast-start".
"fast-start" puts the header at the front so you can start during download.

Hi Serge,

I'm glad there is a solution thanks very much.

Er.. can you explain a little bit more what I have to do ?

Do you mean I have to set up something special in Adobe Premiere Pro before encoding ?

Do you mean I have to insert some new code into my .html page ?

Sorry I am a beginner :)

@Jean-Sam:
Some (German) sources I found in the web say that Adobe Premiere can't export
fast-start mp4 videos.
So you might need extra software for that.
If you have QuickTime Pro, you just can do the Export from Premiere with it.

There is also software which can change your movies after exporting.

I am not an expert in Adobe Premiere. Probably you just start a new thread and ask this question again.

All right, many thanks,

I'll post something when I find something !

Cheers

@Jean-Sam,

Google for "MP4Box"

It's software that will move the moov atoms to the beginning of the MP4 file for fast starting.

Check here: http://www.videohelp.com and on the doom9 forums for a more detailed explanation.

@Ajax By default the mp4box save the files in faststart, 0.5s interleaving:

As of version 0.2.4, MP4Box always stores the file with 0.5 second interleaving and meta-data at the begining, making it suitable for HTTP streaming.

It's your advice to change this with the command -inter?

P.S All my encodes are Megui/mp4box. Great tools...

@Ajax

Sounds good !

This website is just great and the doom9 is great too !

I posted my question there so I hope for an answer shortly. I'll let you know.

Cheers

@ Ajax & Raoul

Ahhh... lots of readers but no answer...

Raoul can you explain how you use mp4box please ?

Try this, the most easy way:
Download the gui for mp4box ->YAMB (2.0.0.8)
Put yamb and mp4box in the same folder.
Set yamb for use mp4box for tagging
Tag a mp4 movie

This should be enough to get the file ready for streaming

(Sorry for my potato english)

@ Raoul

I did everything you said.

Yamb -> Editing -> Click to write/erase tags -> File selection -> Go -> Running process window appears
... then nothing happens (no processing bar, nothing).

I did also :
Yamb -> Creation -> Click to create an MP4 file... -> Add my .mp4 file -> Properties (do I have to change settings ?) -> Go -> Error detected (the log is gone somewhere can't find it)

First of all, perhaps you can tell me which of the two above procedure is the good one ?
Then, any more idea :) (thanks again for you help)

I think is a problem of compatibility between versions.
Try in the oficial site:
http://yamb.unite-video.com/download.html

Download the full pack installer. It´s not the more updated version of mp4box but...

I re-installed Yamb & MP4Box all right.

The processing of the file is ok (please confirm that Yamb -> Creation... is the right procedure)

However the result does not change and the file is still fully downloaded before it starts.

Are we searching in the right spot ?

It is a matter of player, file, codec, speed ? I do not know...

@Raoul

Ok I've found how to...

I downloaded Adobe air + a small add-on called "QTindexswapper"

It puts the moov atoms at the beginning of the file, very easily

Jesus I'm happy !!!

Cheers

Sam (from France, lol)

Sorry to answer so late ... The right procedure is: Put mp4box and mp4 file in the same folder and open the COMMAND PROMPT and write: mp4box -inter mymp4file.mp4 or mp4box -inter [optional interleaving data] mymp4file.mp4. Enter. Finis.
Yamb is only for avoid the use of the command prompt. Muxing separated video and audio in mp4 with Yamb is a way. Tagging is another. According to my tests, work. But the official and safe method is the first.

There is an error in my previous message
Correctly is:
mp4box -inter 0 mymp4file.mp4 (or) mp4box -inter [optional interleaving data in seconds] mymp4file.mp4.

http://gpac.sourceforge.net/doc_mp4box.php

Hello,
Thank you for your player! Just a few issues:
1. With Flash .flv files, the player defaults to "return to beginning". Is there a way to have it "pause at last frame"? Also with Flash, there are noticeable artifacts on white text that are not there in the file itself or on other FLV players. Any idea?
2. With H.264, we have audio sync problems. The H.264 plays with the .FLV extension, but out of sync.
Thanks for your help.
Kevin

@H264:
-I think that the artifacts in flv files should be there because graphic card issues. Try with 3.15 (not hardware scaling) to check.

@All:
Nice info here. Thank You.

Good tip - also how far off is the v4 player. Does it contain any optimization code?

4.0 is released next week ;) It's AS3 so the native code will run a lot faster. Any optimizations to MP4 files you'll have to do yourself of course...

Looking forward to "JW Media Player 4" and "Flash Player 10"
I made some tests:

Mac OSX 10.4.11
Safari 3.1
Flashplayer 10 Beta
G4 Dual 1 Ghz
Geforce 4

Setting1:

JW Wizard (JWMP 3.16)
Video: http://weggli-tv.com/video/interviews40.mp4
(b-frames, multipass 1600 kbit/s)

Flashplayer 10 Beta playing h.264-videos is still very buggy.
Most of the time there are just sureal pictures, but if I zapp
through the timeline, the video gets visible and plays smoother than ever before.
For some seconds there are no dropped frames, even in fullscreen...
This is new!
If the Flashplayer 10 will playback high-quality h.264-videos really that smooth
even on older PCs/Macs,...that will be just great.

Setting2:

Player Testpage "JW Media Player 4.0 beta"
Video: http://weggli-tv.com/video/interviews40.mp4
(b-frames, multipass 1600 kbit/s)

As in Setting1, the playback of h.264-videos is very buggy.
But in addition: when I zapp through the timeline and the video gets visible,
(like in the Flash Player 9,0,124,0) it plays just with about 3 fps...
The improve is gone.

Have made some intensive testing during the last week and I can't get any H.264 video to play back smoothly without jerkiness in panoramic scenes. It's as if the decoder is dropping frames. To see what I am talking about, encode a video with many camera pans and tilts.

I have tested with various setups and versions, both mac and pcs, IE, Firefox, Safari, flash player version 9,0,115,0 and 9,0,124,0 and nothing seems to play smoothly. This is NOT related to too high CPU usage - it is something related to the flash video decoder.

All test files plays perfectly in VLC and Quicktime too so the problem is only related to Flash playback.
Has anyone succeeded in creating an H.264-file that plays smoothly, without frame drops, in flash player and how did you create those files?

Thanks /Peter

Here's another guy reporting the same thing as I did above, complete with test beds and sample files.
http://www.sabandcom.com/H264/index.html

Anyone knows of someone at Adobe to contact about this?

@Peter:
As I described above I got the best results with the iPod-Export from QuickTime.
It exports at constant bitrate, in Low-Complexity Profile...

We also did some tests and noticed the jitter. Couldn't really get rid of it, no matter what. Low-complexity and CBR does seem the way to go.

@Peter: The lag in the 4.0 player was probably because it didn't have hardware fullscreen yet. It's in there now, so it should be a lot better.

How about high bandwidth files? I am planning to use h264 3200kbps 720x576 resolution mp4 files. They play back just fine in my computer, but it has a pretty good CPU. Will I instantly "kill" every CPU that isn´t top of the line with these settings?

I created FLV file using Sorrenson. The files 720x480 NTSC, plays nice and smooth, but the full screen... its jerky.
Any idea, how to fix that?

Both, please retry this with the 4.0 player (released today). It has the fullscreen settings tweaked.

x264 is indeed quite flexible, you can use some really simple settings for HD stuff (with some decent bitrate) and get good playback performance imho, example;
http://somestuff.org/flashAVC/flvplayer.php?moviename=movies/FighterPilot-x1280y720.mp4

I would say:
The JW Mediaplayer 4.0 is really a great improvement!
I don't have any issues about stuttering HQ videos any more, even on older PCs.