movie FPS

1
Hi
after creating MOV file and define the FPS, i verifyi if the defined FPS is correct by opening quicktime ---> window----> show movie inspector. in this window there are two fields concerning FPS.
"movie FPS" , which presents the correct FPS.
"playing FPS", which presents the FPS during play mode. The problem is that this field present diffrents values (lower than movie FPS) during play mode and not the defined FPS, which means the movie skips part of the frames.
Is there any way to overcome this problem?

Thanks,
Keren
2
what that is telling you is that your system isn't able to load, process, and playback all the video frames in your movie file fast enough.

all the usual suspects that can negatively impact real-time system performance might be causing this, as well as the frame size and type of encoding that you have chosen for your video output file.

what are the specs of your machine, and how exactly are you creating the video, and what are your output settings?



--- In psychtoolbox@yahoogroups.com, "kerenlesinger" <keren.lesinger@...> wrote:
>
> Hi
> after creating MOV file and define the FPS, i verifyi if the defined FPS is correct by opening quicktime ---> window----> show movie inspector. in this window there are two fields concerning FPS.
> "movie FPS" , which presents the correct FPS.
> "playing FPS", which presents the FPS during play mode. The problem is that this field present diffrents values (lower than movie FPS) during play mode and not the defined FPS, which means the movie skips part of the frames.
> Is there any way to overcome this problem?
>
> Thanks,
> Keren
>
3
hi
i'm using the dispaly frame rate via Screen('FrameRate', 0);
the frane rate is 60hz.
the movie was created using "QTWriter".
i also tried to insert manually a lower value for frame rate value, but it happened again.

--- In psychtoolbox@yahoogroups.com, "elladawu" <elladawu@...> wrote:
>
> what that is telling you is that your system isn't able to load, process, and playback all the video frames in your movie file fast enough.
>
> all the usual suspects that can negatively impact real-time system performance might be causing this, as well as the frame size and type of encoding that you have chosen for your video output file.
>
> what are the specs of your machine, and how exactly are you creating the video, and what are your output settings?
>
>
>
> --- In psychtoolbox@yahoogroups.com, "kerenlesinger" <keren.lesinger@> wrote:
> >
> > Hi
> > after creating MOV file and define the FPS, i verifyi if the defined FPS is correct by opening quicktime ---> window----> show movie inspector. in this window there are two fields concerning FPS.
> > "movie FPS" , which presents the correct FPS.
> > "playing FPS", which presents the FPS during play mode. The problem is that this field present diffrents values (lower than movie FPS) during play mode and not the defined FPS, which means the movie skips part of the frames.
> > Is there any way to overcome this problem?
> >
> > Thanks,
> > Keren
> >
>
4
Hey folks,

That paper showed on my twitter feed and I thought some of you could find it interesting (pdf attached):
http://www.ncbi.nlm.nih.gov/pubmed/23640111

@+

--
Remi Gau
5
On Windows 7, playing back high resolution videos (1920x1080) initially worked okay for us on a machine with an Nvidia Quadro 2000 graphics card, but didn't seem to carry over to a relatively similar powered machine with an AMD Radeon HD 5870. After lots of trial and error, I discovered that setting "pixelFormat" = 6 in Screen('OpenMovie') fixed this problem on the latter machine. Some of the "specialFlags1" options might also help you depending on your circumstances. I would actually try all combinations of these two parameters, they are documented here: http://docs.psychtoolbox.org/OpenMovie

YMMV.

Best,
Matthew


On Thu, May 9, 2013 at 10:10 AM, Alan Robinson <arcogsci@...> wrote:

I personally found the best performance with mjpeg that was cached in ram. But that was under winxp. Mario is right, look at old posts for lots of detail on this question.

As a side note the yahoo mailing list has a very bad search engine. I'm sure that's part of the reason we get so many repeated questions.

On May 8, 2013 10:25 PM, "Mario" <mario.kleiner@...> wrote:



If you used QTWriter from GitHub...

https://github.com/horchler/QTWriter

... then i'm not surprised. It seems to encode video as png, jpeg or tiff image sequences, which will probably not provide great performance at all. You need a different tool to create your movies.

For high framerates you'll need something like H264 encoding in some modern container format like MP4 or Matroska. There were a couple of answers to these topics on the forum, e.g., from Tobias Wolf.

But even with well encoded movies, high framerate playback, e.g, 60 fps with high resolution is a demanding task. It needs a fast multi-core computer and a few more non-standard parameter settings to achieve that. Also maximum performance is currently only supported on Linux and with some work on OSX.

-mario

--- In psychtoolbox@yahoogroups.com, "kerenlesinger" <keren.lesinger@...> wrote:
>
>
> hi
> i'm using the dispaly frame rate via Screen('FrameRate', 0);
> the frane rate is 60hz.
> the movie was created using "QTWriter".
> i also tried to insert manually a lower value for frame rate value, but it happened again.
>
> --- In psychtoolbox@yahoogroups.com, "elladawu" <elladawu@> wrote:
> >
> > what that is telling you is that your system isn't able to load, process, and playback all the video frames in your movie file fast enough.
> >
> > all the usual suspects that can negatively impact real-time system performance might be causing this, as well as the frame size and type of encoding that you have chosen for your video output file.
> >
> > what are the specs of your machine, and how exactly are you creating the video, and what are your output settings?
> >
> >
> >
> > --- In psychtoolbox@yahoogroups.com, "kerenlesinger" <keren.lesinger@> wrote:
> > >
> > > Hi
> > > after creating MOV file and define the FPS, i verifyi if the defined FPS is correct by opening quicktime ---> window----> show movie inspector. in this window there are two fields concerning FPS.
> > > "movie FPS" , which presents the correct FPS.
> > > "playing FPS", which presents the FPS during play mode. The problem is that this field present diffrents values (lower than movie FPS) during play mode and not the defined FPS, which means the movie skips part of the frames.
> > > Is there any way to overcome this problem?
> > >
> > > Thanks,
> > > Keren
> > >
> >
>


6
I've read a past paper on this idea to a similar effect. I'll see if I can track it down.


On Tue, May 7, 2013 at 8:48 AM, Remi Gau <remi_gau@...> wrote:
[Attachment(s) from Remi Gau included below]

Hey folks,

That paper showed on my twitter feed and I thought some of you could find it interesting (pdf attached):
http://www.ncbi.nlm.nih.gov/pubmed/23640111

@+


--
Remi Gau