need urgent help with rendering issues. video momentarily freezing and stuttering at DVinfo.net

Adi Head · July 8th, 2013, 11:45 AM

hi. hopefully someone will be able to help me quickly.

i'm having trouble rendering a film that needs to be screened tomorrow.

it was shot HD 1920X1080 24p on a canon 5d mark ii.

edited on vegas 9 on windows xp.

the request was to render the video as:

Video : dnxhd 185 or dnxhd 220 4:2:2 YUV 1920x1080 (LE) mov file
Audio : PCM s16 - 16 Bit 48000 Hz Stereo Little Endian (LE) (sowt)

so i downloaded the dnxhd codec and rendered as a mov using dnxhd 185, 25fps (because the screening is in PAL land).

i receive no errors, but the result is problematic. at certain points in the video it starts to stutter, then goes back to normal playing, then after a minute or two can start to stutter again. i've tried several times but i'm getting the same results. the stuttering is not consistent as to where it happens in the video. with one render it happens after 2 minutes, with another render it happens after one minute.

the video material is on a hard drive mounted in an external enclosure, connected via USB.

the veg file is on the computer internal hard drive. rendering to the same internal hard drive. i know this isn't ideal, but i don't have any other choice at the moment and i've been successful in rendering with this setup many times until now.

i've also tried rendering first to avi (lagarith) with the intention of then rendering that file to the mov dnxhd format, but the lagarith file seemed to produce a different sort of problem. it didn't get stuck, but the movement of the picture seemed a bit jumpy, like it was skipping frames or something, although the speed seemed normal. not quite sure how to describe it.

does anyone have any suggestions?
at this point i'm pretty desperate.

EDIT: i've also noticed that the momentary freeze ups and stutters are not consistent with each playing. if i play the same rendered file 3 times, it will occur with all 3 times, but at different places during the film. so it seems like it is happening randomly during the playing of the file rather than something embedded in the file at a certain point. i tried copying the file to a different computer, thinking it might have to do with the computer and/or player. i tried with a windows 7 64bit computer using both vlc player and quicktime. both started freezing up at some point or other.

Adi Head · July 8th, 2013, 12:42 PM

Without exactly knowing what i'm talking about, i somehow have a feeling that this is some sort of a caching issue, but apparently this issue is occurring as a result of the render.

after letting the video play through from beginning to end, I then tried to play it once again on the same player. At some point it did freeze up a bit, but it definitely showed much less symptoms than the previous playing. Furthermore, when the freeze ups occur, the playing strip in VLC media player, where the round playhead advances, suddenly turns from blue to red for a moment, then turns back to blue and continues.

That said, I believe that the source of the issue is in the rendering, since it seems to be happening across different computers and different media players.

Adi Head · July 8th, 2013, 01:11 PM

oh and one more thing - the media clips were converted to GoPro Cineform Codec v.7.4.0 before editing.

(sorry about the multiple posts)

Adi Head · July 8th, 2013, 02:59 PM

i've spoken with the festival management.

alternatively, does anyone know what format would be compatible with an AJAX video player. i've tried looking it up, but can't really find anything except listings for AJAX cinema complexes.

Gerald Webb · July 8th, 2013, 03:39 PM

Quote:

Originally Posted by Adi Head

the video material is on a hard drive mounted in an external enclosure, connected via USB.

the veg file is on the computer internal hard drive. rendering to the same internal hard drive. i know this isn't ideal, but i don't have any other choice at the moment and i've been successful in rendering with this setup many times until now.

EDIT: i've also noticed that the momentary freeze ups and stutters are not consistent with each playing. if i play the same rendered file 3 times, it will occur with all 3 times, but at different places during the film.

Just from what you have said above, I would have to say it is read related, not the actual rendered file. Have you got a Raid drive to play it from? Or try rendering the Dnxhd file to something small, mpg2 mp4 etc then see if it plays through ok. If so, just have faith that the venue will have no trouble playing it.

Adi Head · July 8th, 2013, 03:39 PM

i think i may have figured it out.
i moved the rendered file to the external hard drive which is a 7200rpm drive as opposed to the internal laptop drive which is 5600rpm i believe. playing it from the 7200rpm drive was perfect.

so it looks like it is not a rendering issue but a playback issue : )

that said, the festival organizers seem to be facing the same problem, so it could be that they are checking on a slow drive. due to time zone difference, i can't verify that now.

i have written to them explaining how i was able to overcome the problem, but just in case i want to send them a backup file that can be played on this AJAX thing, whatever that is.

can someone please recommend how to render?
which format, codec, etc?

thanks!

Gerald Webb · July 8th, 2013, 03:48 PM

Looks like its software,
AJAX Tutorials from lynda.com

Id render out a high quality MP4 to have on hand as well. Might save you if the organisers aren't set up very well.
Good luck.

Adi Head · July 8th, 2013, 03:55 PM

thanks gerald. i think the ajax referenced in the lynda.com link is some sort of programming code thing.
it seems there are a lot of what is called "ajax cinemas":

https://www.google.com/search?q=ajax...hrome&ie=UTF-8

however, i can't really find much information about what exactly it is or what files could be compatible with it.

July 8th, 2013, 11:45 AM	#1
Adi Head Major Player Join Date: Aug 2002 Location: Brooklyn, NY Posts: 642	need urgent help with rendering issues. video momentarily freezing and stuttering hi. hopefully someone will be able to help me quickly. i'm having trouble rendering a film that needs to be screened tomorrow. it was shot HD 1920X1080 24p on a canon 5d mark ii. edited on vegas 9 on windows xp. the request was to render the video as: Video : dnxhd 185 or dnxhd 220 4:2:2 YUV 1920x1080 (LE) mov file Audio : PCM s16 - 16 Bit 48000 Hz Stereo Little Endian (LE) (sowt) so i downloaded the dnxhd codec and rendered as a mov using dnxhd 185, 25fps (because the screening is in PAL land). i receive no errors, but the result is problematic. at certain points in the video it starts to stutter, then goes back to normal playing, then after a minute or two can start to stutter again. i've tried several times but i'm getting the same results. the stuttering is not consistent as to where it happens in the video. with one render it happens after 2 minutes, with another render it happens after one minute. the video material is on a hard drive mounted in an external enclosure, connected via USB. the veg file is on the computer internal hard drive. rendering to the same internal hard drive. i know this isn't ideal, but i don't have any other choice at the moment and i've been successful in rendering with this setup many times until now. i've also tried rendering first to avi (lagarith) with the intention of then rendering that file to the mov dnxhd format, but the lagarith file seemed to produce a different sort of problem. it didn't get stuck, but the movement of the picture seemed a bit jumpy, like it was skipping frames or something, although the speed seemed normal. not quite sure how to describe it. does anyone have any suggestions? at this point i'm pretty desperate. EDIT: i've also noticed that the momentary freeze ups and stutters are not consistent with each playing. if i play the same rendered file 3 times, it will occur with all 3 times, but at different places during the film. so it seems like it is happening randomly during the playing of the file rather than something embedded in the file at a certain point. i tried copying the file to a different computer, thinking it might have to do with the computer and/or player. i tried with a windows 7 64bit computer using both vlc player and quicktime. both started freezing up at some point or other. Last edited by Adi Head; July 8th, 2013 at 12:29 PM. Reason: following further testing

July 8th, 2013, 12:42 PM	#2
Adi Head Major Player Join Date: Aug 2002 Location: Brooklyn, NY Posts: 642	Re: need urgent help with rendering issues. video momentarily freezing and stuttering Without exactly knowing what i'm talking about, i somehow have a feeling that this is some sort of a caching issue, but apparently this issue is occurring as a result of the render. after letting the video play through from beginning to end, I then tried to play it once again on the same player. At some point it did freeze up a bit, but it definitely showed much less symptoms than the previous playing. Furthermore, when the freeze ups occur, the playing strip in VLC media player, where the round playhead advances, suddenly turns from blue to red for a moment, then turns back to blue and continues. That said, I believe that the source of the issue is in the rendering, since it seems to be happening across different computers and different media players.

July 8th, 2013, 01:11 PM	#3
Adi Head Major Player Join Date: Aug 2002 Location: Brooklyn, NY Posts: 642	Re: need urgent help with rendering issues. video momentarily freezing and stuttering oh and one more thing - the media clips were converted to GoPro Cineform Codec v.7.4.0 before editing. (sorry about the multiple posts)

July 8th, 2013, 02:59 PM	#4
Adi Head Major Player Join Date: Aug 2002 Location: Brooklyn, NY Posts: 642	Re: need urgent help with rendering issues. video momentarily freezing and stuttering i've spoken with the festival management. alternatively, does anyone know what format would be compatible with an AJAX video player. i've tried looking it up, but can't really find anything except listings for AJAX cinema complexes.

July 8th, 2013, 03:39 PM	#6
Adi Head Major Player Join Date: Aug 2002 Location: Brooklyn, NY Posts: 642	Re: need urgent help with rendering issues. video momentarily freezing and stuttering i think i may have figured it out. i moved the rendered file to the external hard drive which is a 7200rpm drive as opposed to the internal laptop drive which is 5600rpm i believe. playing it from the 7200rpm drive was perfect. so it looks like it is not a rendering issue but a playback issue : ) that said, the festival organizers seem to be facing the same problem, so it could be that they are checking on a slow drive. due to time zone difference, i can't verify that now. i have written to them explaining how i was able to overcome the problem, but just in case i want to send them a backup file that can be played on this AJAX thing, whatever that is. can someone please recommend how to render? which format, codec, etc? thanks!

July 8th, 2013, 03:48 PM	#7
Gerald Webb Trustee Join Date: Oct 2009 Location: Central Coast Australia Posts: 1,046	Re: need urgent help with rendering issues. video momentarily freezing and stuttering Looks like its software, AJAX Tutorials from lynda.com Id render out a high quality MP4 to have on hand as well. Might save you if the organisers aren't set up very well. Good luck. __________________ http://vimeo.com/livewebvideo

July 8th, 2013, 03:55 PM	#8
Adi Head Major Player Join Date: Aug 2002 Location: Brooklyn, NY Posts: 642	Re: need urgent help with rendering issues. video momentarily freezing and stuttering thanks gerald. i think the ajax referenced in the lynda.com link is some sort of programming code thing. it seems there are a lot of what is called "ajax cinemas": https://www.google.com/search?q=ajax...hrome&ie=UTF-8 however, i can't really find much information about what exactly it is or what files could be compatible with it.