Author Topic: Fps problem(motion stutter, jerky movements)  (Read 8617 times)

AQUAR

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Re: Fps problem(motion stutter, jerky movements)
« Reply #15 on: March 27, 2016, 11:14:32 AM »
I think Jan is implying that the bit rate might be to high for your media player to handle and hence the stuttering.
Increasing the rate control (not the same as increasing the video frame rate!) lowers the bit rate (and quality) of the recode, so your media player can keep up with the decoding process.

I am assuming its interlaced because its video of the family and its at the NTSC frame rate.
This is not always true though.

If it's a retail movie on dvd, then its usually film material as opposed to video material (subtle difference!).
That kind is subjected to telecining (NTSC only!) and is best de-interlaced by reversing that process. 

Are you playing back on a TV or PC monitor?
Media players (in case of TV playback) are more likely to drop frames if the video frame rate isn't integer divisible with the TV refresh rate (also a cause of stuttering!). Best to stick with 30 fps in this case (or 60 fps) if in NTSC land or 25 fps in PAL land.
Same kind of thing if playing back on a PC monitor (check what refresh is being used!).

On top if that - it really all depends on how good (if any is used!) the frame interpolation process is (creating new frames on the fly!).

 
« Last Edit: March 27, 2016, 12:51:26 PM by AQUAR »

maximillan

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Re: Fps problem(motion stutter, jerky movements)
« Reply #16 on: March 27, 2016, 03:30:18 PM »
I'm going to watch or play it for TV viewing. I have movies stored on the media player with high bit rates like 10mb but they play smoothly. May be I will try Jan's suggestion on constant rate factor. But what's weird, I tried to 1 min samples at 23.97fps and 29.97 they both played smoothly but when I transcoded the whole 2hr video stuttering was a bit showing on 23 and 29 but when I tried muxing and watching without the audio stream it played smoothly.

maximillan

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Re: Fps problem(motion stutter, jerky movements)
« Reply #17 on: March 27, 2016, 03:37:52 PM »
By the way to add info: why I chose avidemux? Because it's the only transcoder that I had no problems using tried handbrake before but my problem with it some videos tend to have artifacts at the end. Before that was using Total Video Converter the downside to TVC encoded vids(x264) tend to be unstable if you try fast fowarding/reverse the vid during play back vid starts to break up getting green artifacts. So I'm sticking to Avidemux I just have to figure out this stuttering issue with your suggestions. :D

Jan Gruuthuse

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Re: Fps problem(motion stutter, jerky movements)
« Reply #18 on: March 27, 2016, 04:00:42 PM »
>8 >8 but when I tried muxing and watching without the audio stream it played smoothly.
?? audio track is AC3 (dolby) ?? -> convert to stereo (mp2 or AAC) 44100 Hz

maximillan

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Re: Fps problem(motion stutter, jerky movements)
« Reply #19 on: March 27, 2016, 06:31:42 PM »
Yes AC3. What I do is just load and transcode the vid stream to avidemux I notice transcoding time is much faster without any audio streams by 40%

Jan Gruuthuse

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Re: Fps problem(motion stutter, jerky movements)
« Reply #20 on: March 27, 2016, 06:35:50 PM »
You still do have motion stutter, jerky movements with playback? Could be AC3 related, your media player(s) not supporting? AC3 could take cpu power of mediaplayer when no hardware ac3 decoding is present.
« Last Edit: March 27, 2016, 06:38:40 PM by Jan Gruuthuse »

maximillan

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Re: Fps problem(motion stutter, jerky movements)
« Reply #21 on: March 27, 2016, 07:00:27 PM »
Most of the other vids loaded on the media player are AC3 and few are AAC but they play fine.

Jan Gruuthuse

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Re: Fps problem(motion stutter, jerky movements)
« Reply #22 on: March 28, 2016, 07:44:55 AM »
Probably with the re-encoded combination of video and audio, you're reaching the limits of what can be decoded simultaneous by media player.

AQUAR

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Re: Fps problem(motion stutter, jerky movements)
« Reply #23 on: March 28, 2016, 08:17:30 AM »
The bit rate of the encoded video stream needs to be paired with the complexity of the codec if you want to get to the bottom of the stuttering.
Assuming of course that this is actually the problem (not convinced at all!).

AVC is complex enough but HECV goes even further.
The need to keep many referenced frames (or blocks!) in a buffer for proper on the fly decoding may well be to much for the media player for some intervals. Easing up on the AVC settings might help (not experienced in that area myself!).

Some end users were very much into these AVC settings - maybe they can suggest some changes to the default settings.
2 settings (as a guess) to help in that regard:
> reduce the maximum GOP size
> disable B frames as references

maximillan

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Re: Fps problem(motion stutter, jerky movements)
« Reply #24 on: March 28, 2016, 08:40:08 AM »
Jan- that could be possible.

AQUAR- stuttering is definitely the problem I would not bother if the stuttering was minimal but people walking across the screen seems like moving and pausing motion it's not that smooth.

AQUAR

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Re: Fps problem(motion stutter, jerky movements)
« Reply #25 on: March 28, 2016, 08:51:40 AM »
@ maximillan

I meant - not convinced that the reason for the stuttering is caused by bit rate / codec complexity issues associated with the media player.
Only way to find out is to ease up on loading the media player.
Some suggestions have been given for you to try out and see if it helps.

Some other causes have also been suggested for you to look at. 

maximillan

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Re: Fps problem(motion stutter, jerky movements)
« Reply #26 on: March 28, 2016, 09:04:42 AM »
Yes that's what I'm doing taking each suggestions by you guys trying it out one by one till I get the problem solved.😊 Regarding bit rates so far I have not gone above 4k but I will try lower down to 19..kbps hope quality won't suffer.

AQUAR

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Re: Fps problem(motion stutter, jerky movements)
« Reply #27 on: March 28, 2016, 11:42:00 AM »
@ maximillan

That's the way.

Do try to configure the x264 settings as I am curious if it will help.
Configure - Frame Tab - B Frames as reference - select disabled.

This will lower the compression ability (increase bit rate!) but makes it easier (faster) to decode.
At least that what I am thinking it will do. 

Also as Jan implied - if the AC3 audio is 5.1 channels - remix as stereo (2 channel) AC3 or AAC.
This too will reduce the decoding overhead on the media player.
« Last Edit: March 28, 2016, 12:07:37 PM by AQUAR »

maximillan

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Re: Fps problem(motion stutter, jerky movements)
« Reply #28 on: March 28, 2016, 12:08:15 PM »
I will try that AQUAR thanks I never touched Frame Tab before but now I will try this thanks hope this is it.😊

For AC3 okay will downmix it to AAC stereo👍
« Last Edit: March 28, 2016, 12:11:27 PM by maximillan »

maximillan

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Re: Fps problem(motion stutter, jerky movements)
« Reply #29 on: April 07, 2016, 02:04:58 PM »
Hello I'm back just to update with all of the suggestions and test I made one success result came from a couple of combined suggestions and one which sounded weird to get the perfect result.

Prodecure was: original file had to be first transcoded by TVC(total video converter) pro. Using system default settings for fps and bitrate at 4600kbs out file had a constant fps of 25 file size came out the same 4.1gb(looseless 100%) like the original file.
Load encoded file to Avidemux 2.5.6 not 2.6(2.6 would always output a file with variable fps) use constant crf no other filters etc encode. Result a file with a size of 2.1gb and constant fps of 25. Bitrate of file was at 3150kbs and picture quality was superb the way I like it. Of all the settings I tried that's the only procedure that worked I don't know why the only draw back that I just may accept is transcoding time since I had to transcode twice using to different programs.

So that's my update for everyone and thank you for all your suggestions I could not have fixed this without your inputs. I guess in the end the thing that made the stuttering go away was having a really "constant" fps.👍