hello,
im still working on the project using many videos, i've got problem with frame rate acuracy.
i test with only 1 movie, so the CPU are very low. i'm using apple intermediate codec. gem fps is set to 50, video speed is varing from about 1 to 10
the problem is that visually, the video does not play very smooth.
while testing time between frame with :
gemhead | t b b | \ realtime | print
i've got average number 20ms (so the fps is 50), but i can have lot's of diferences from 1 frame to one other. i can have 1 frame at 35ms, and the other at 5ms etc so the result is not very good.
changing codec / size of the movie does not really change results
i really don't know what i could do to improve performances.
does anyone have an idea?
thanks Cyrille
How many movies? At some point the hard drive will become a limiting factor. You will particualrly see skips when movies load and hit the loop point at the end of the clip.
Playing any movie back at 10 times the normal speed will not be very smooth.
You can try to load the movies into RAM with the 'ram' message on OSX or make a RAM disk and copy movies in there if you have the memory.
On 5/15/07, cyrille henry cyrille.henry@la-kitchen.fr wrote:
hello,
im still working on the project using many videos, i've got problem with frame rate acuracy.
i test with only 1 movie, so the CPU are very low. i'm using apple intermediate codec. gem fps is set to 50, video speed is varing from about 1 to 10
the problem is that visually, the video does not play very smooth.
while testing time between frame with :
gemhead | t b b | \ realtime | print
i've got average number 20ms (so the fps is 50), but i can have lot's of diferences from 1 frame to one other. i can have 1 frame at 35ms, and the other at 5ms etc so the result is not very good.
changing codec / size of the movie does not really change results
i really don't know what i could do to improve performances.
does anyone have an idea?
thanks Cyrille
GEM-dev mailing list GEM-dev@iem.at http://lists.puredata.info/listinfo/gem-dev
chris clepper a écrit :
How many movies?
just 1!
At some point the hard drive will become a limiting factor. You will particualrly see skips when movies load and hit the loop point at the end of the clip.
Playing any movie back at 10 times the normal speed will not be very smooth.
the movie are very slow motion (clouds), so 10 times the normal speed make the movement visible.
You can try to load the movies into RAM with the 'ram' message on OSX or make a RAM disk and copy movies in there if you have the memory.
i'll try, but i don't think the problem comes from the HD, or CPU, as i've got only 1 movie and this computer is able do play lot's more...
thanks cyrille
On 5/15/07, cyrille henry cyrille.henry@la-kitchen.fr wrote:
hello,
im still working on the project using many videos, i've got problem with frame rate acuracy.
i test with only 1 movie, so the CPU are very low. i'm using apple intermediate codec. gem fps is set to 50, video speed is varing from about 1 to 10
the problem is that visually, the video does not play very smooth.
while testing time between frame with :
gemhead | t b b | \ realtime | print
i've got average number 20ms (so the fps is 50), but i can have lot's of diferences from 1 frame to one other. i can have 1 frame at 35ms, and the other at 5ms etc so the result is not very good.
changing codec / size of the movie does not really change results
i really don't know what i could do to improve performances.
does anyone have an idea?
thanks Cyrille
GEM-dev mailing list GEM-dev@iem.at http://lists.puredata.info/listinfo/gem-dev
chris clepper a écrit :
How many movies? At some point the hard drive will become a limiting factor. You will particualrly see skips when movies load and hit the loop point at the end of the clip.
Playing any movie back at 10 times the normal speed will not be very smooth.
You can try to load the movies into RAM with the 'ram' message on OSX or make a RAM disk and copy movies in there if you have the memory.
this improve playback. but unfortunatly, i have only 4Go of Ram, and 5Go of movie (+ 1Go of sound that are already in the ram) so everything will not fit.
as i use 10 diferents movies (read 1 after the other), is it possible to move a movie in ram with a low priority thread? (sending the ram message does stop everything for few secs)
thanks cyrille
On 5/15/07, cyrille henry cyrille.henry@la-kitchen.fr wrote:
hello,
im still working on the project using many videos, i've got problem with frame rate acuracy.
i test with only 1 movie, so the CPU are very low. i'm using apple intermediate codec. gem fps is set to 50, video speed is varing from about 1 to 10
the problem is that visually, the video does not play very smooth.
while testing time between frame with :
gemhead | t b b | \ realtime | print
i've got average number 20ms (so the fps is 50), but i can have lot's of diferences from 1 frame to one other. i can have 1 frame at 35ms, and the other at 5ms etc so the result is not very good.
changing codec / size of the movie does not really change results
i really don't know what i could do to improve performances.
does anyone have an idea?
thanks Cyrille
GEM-dev mailing list GEM-dev@iem.at http://lists.puredata.info/listinfo/gem-dev
On 5/15/07, cyrille henry cyrille.henry@la-kitchen.fr wrote:
this improve playback. but unfortunatly, i have only 4Go of Ram, and 5Go of movie (+ 1Go of sound that are already in the ram) so everything will not fit.
as i use 10 diferents movies (read 1 after the other), is it possible to move a movie in ram with a low priority thread? (sending the ram message does stop everything for few secs)
Do you just play each clip from start to end with no looping?
thanks
cyrille
On Tue, 2007-05-15 at 16:46 +0200, cyrille henry wrote:
hello,
im still working on the project using many videos, i've got problem with frame rate acuracy.
i test with only 1 movie, so the CPU are very low. i'm using apple intermediate codec. gem fps is set to 50, video speed is varing from about 1 to 10
the problem is that visually, the video does not play very smooth.
i had a similar issue once. i tried to play a movie with the specs 720x576 @ 25fps on a osx box. though i set the framerate of gem also to 25fps, the movie stuttered a bit when played in gem. since i used the [auto 1( option of [pix_film], i tried a different method of syncing: i made a counter, which was triggered by [gemhead], and used the output of the counter to set the frame-number of [pix_film]. for some reason, this worked much better and gemwin and the movie were perfect in sync and no stuttering was visible anymore.
roman
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cyrille henry wrote:
hello, i'm using apple intermediate codec.
here is my story so far: I have experienced that using a wrong codec or color mode can strongly affect the cpu. even if you are on a mac, gem does not support all the driver features of other mac native programs (as far as I know). the fastest codec for me was fotojpeg. uyvy would be the fastest colormode, but I think that is not supported on gem too, and not at all on non-macs. the apple intermediate codec seems to be almost fotojpeg, but if not supported by gem still a codec that has to be reencoded to be playable within gem. otoh that will increase your filesize even more... marius.
On 5/15/07, marius schebella marius.schebella@gmail.com wrote:
cyrille henry wrote:
hello, i'm using apple intermediate codec.
here is my story so far: I have experienced that using a wrong codec or color mode can strongly affect the cpu. even if you are on a mac, gem does not support all the driver features of other mac native programs (as far as I know).
Like what features?
the
fastest codec for me was fotojpeg.
There are many more efficient codecs but most are specific to a standard. DVCPro-HD at 1080 or 720 is far faster than P-JPEG
uyvy would be the fastest colormode,
2vuy is just as efficient and better supported which is why GEM uses it on OSX.
but I think that is not supported on gem too, and not at all on
non-macs. the apple intermediate codec seems to be almost fotojpeg, but if not supported by gem still a codec that has to be reencoded to be playable within gem. otoh that will increase your filesize even more...
Apple Intermediate is more efficient than Photo-JPEG. It is fully supported by GEM.
marius.
GEM-dev mailing list GEM-dev@iem.at http://lists.puredata.info/listinfo/gem-dev
chris clepper wrote:
I have experienced that using a wrong codec or color mode can strongly affect the cpu. even if you are on a mac, gem does not support all the driver features of other mac native programs (as far as I know).Like what features?
I was thinking Gem does not support all codecs.
the fastest codec for me was fotojpeg.There are many more efficient codecs but most are specific to a standard. DVCPro-HD at 1080 or 720 is far faster than P-JPEG
with "faster" do you mean less cpu consuming? I thought the fastest/less cpu consuming is a frame by frame codec like photo-jpeg because the gfx card can just take the jpegs and texture them onto a geo???
uyvy would be the fastest colormode,2vuy is just as efficient and better supported which is why GEM uses it on OSX.
maybe I was thinking of the isight, which uses uyvy, and a conversion slows the process down.
Apple Intermediate is more efficient than Photo-JPEG. It is fully supported by GEM.
since you are probably the only one who knows that, can you explain how gem deals with the codecs? only if you have time... I do not understand why the apple intermediate should be faster for example when using the movie as a texture for a rectangle than the frame by frame jpeg compression?
marius.
On 5/15/07, marius schebella marius.schebella@gmail.com wrote:
I was thinking Gem does not support all codecs.
GEM supports all Quicktime codecs on OSX, Directshow and Quicktime codecs on Windows and quite a few on Linux (depending on what libs you build).
with "faster" do you mean less cpu consuming? I thought the fastest/less
cpu consuming is a frame by frame codec like photo-jpeg because the gfx card can just take the jpegs and texture them onto a geo???
All codecs have to be decompressed into RAM and then uploaded to the graphics card.
maybe I was thinking of the isight, which uses uyvy, and a conversion
slows the process down.
The iSight might use 'Component' video UYVY but the conversion is pretty simple and fast. Often the device will do the conversion in hardware or the driver does it automatically. '2vuy' is probably the most universal format for YUV video.
since you are probably the only one who knows that, can you explain how
gem deals with the codecs? only if you have time... I do not understand why the apple intermediate should be faster for example when using the movie as a texture for a rectangle than the frame by frame jpeg compression?
Apple Intermediate Codec uses different code than Photo-JPEG for compression and decompression. In particular, Apple Intermediate is multi-threaded internally and it avoids some slow code that the JPEG codec uses.
I have started using AIC for work since it takes any video dimensions unlike HDV, DV or DVCPro. Those codecs are all faster than AIC at their native resolutions but are not flexible enough for some uses. Also, the DVCPro codecs only come with Final Cut and are not part of the standard Quicktime install. If you don't have Apple Intermediate then copy the codec from a mahcine that has it in /Library/Quicktime/ or install iMovie.
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chris clepper -
cyrille henry -
marius schebella -
Roman Haefeli