I am experiencing stuttering playback and a strange noise on playback especially when unrendered h.264 is involved. When it works, it works fine but occasionally this will happen:
www.givethatmanajob.com/Public/issues/StutterPlayback_a.mov
I am suspecting my GFX card may be having trouble. All software is current. Any throughts?
iMac, Mac OS X (10.7.2)
transcode your h264 into prores and my bet is your stuttering will end.
N unfortunately. It's Especially with H.264 (unless that's my imagination) but it also occures with Prores. Still too, interestingly.
Even if it was just H.264 transcoding to prores would not be an acceptable solution to the issue. Especially since the footage in the example was shot with an iphone. FCPX should eat it right up.
I have run an AHT and errors have been repoted so it's off to the Macstore this afternoon! I'll report back.
I'm not sure why it would continue to be jerky with prores. A slow hard drive...having the fcpx folders on your boot drive...and of course whatever is causing your hardware test errors could be the issue, however just because it's an apple iPhone and and Apple softwware product doesn't mean you won't have to transcode. Some macs and video cards may be fast enough to work with h264 with no need to transcode but you'll still pay for not transcoding when you add transitions and effects and export. if you find there is no problem with h264 and your workflow, then great, but at the first sign of stuttering and unwanted rendering then transcoding is the first thing to check. h264 is compressed and doing that decompression on the fly is the source of many stuttering issues, regardless of whether it's filmed on an iPhone or not.
just because it's an apple iPhone and and Apple softwware product doesn't mean you won't have to transcode. Some macs and video cards may be fast enough to work with h264 with no need to transcode but you'll still pay for not transcoding when you add transitions and effects and export.
Add enough transitions and effects and you'll have to pay whether it's prores or not 😉
I linked to a video in the original post to demonstrate the issue and as you can see in the video, no transitions, no effects.
Sorry for the lack of specs - my fault.
The footage resides on a Thunderbolt RAID. The machine being used is an iMac i7 with 16GB of Ram.
I think you have more ythan enough machine for this. Makes me wonder about the RAID. Any indications it might be having problems? (What is an AHT test?)
Russ
I think an iPad is enough machine for this 😉
AHT is the Apple Hardware test. Its the diagnostic test they run in-store, but you can run it from home by booting up while holding down option-D
I'm thinking that's main suspect, the error that is showing up in the diagnotic. I'll know more this afternoon i guess.
The hardware test does nothing for data throughput on external devices. You are using a separate, supported drive for your content, aren't you?
Hi Tom. The AHT does not diagnose external devices of course. Hence the name.
But it will diagnose a faulty GFX card, logic board or other Apple hardware issue which can impact one's system in strange and interesting ways.
As I stated above yes I am using a seperate supported drive. The Promise Thunderbolt R4 Raid.
To me, it looks like the video playback is wrong!
1: Are the original files playing ok in the Finder?
2: Any Proxy generated or, are you playing the original media?
3: Any render files in the project you could trash?
To me, it looks like the video playback is wrong!
I have half a mind to mark that comment as the one that solved my issue, just for a laugh.
Seriously tho...
1: Are the original files playing ok in the Finder? Yes.
2: Any Proxy generated or, are you playing the original media? Original, and optimized. I don't work with Proxiers at the moment.
3: Any render files in the project you could trash? I created a fresh project for the purposes of the screencapture so no.
ROFL.. about my own remark. In retrospect, that was bad english.. sorry!
If I can refrase that, "it seems like the frames are being rendered on-screen in messed up order, randomly" - does that make any more sense? :-)
If you have Original AND Optimized, then what is your settings in
Preferences: Playback: Playback? (Use proxy or Use Original or optimized..) and Better Performance or HQ?
Do you have a 'Transcoded Media/High Quality Media' folder in the Event folder? If yes, try trash if (while FCPX is closed).
N unfortunately. It's Especially with H.264 (unless that's my imagination) but it also occures with Prores. Still too, interestingly.
Even if it was just H.264 transcoding to prores would not be an acceptable solution to the issue. Especially since the footage in the example was shot with an iphone. FCPX should eat it right up.
Not sure what this means, but did your transcode the media or not? Can't tell what you're doing, but your ProRes meia should not stutter on playback in the viewer.
Coming from an iPhone means nothing, especially as the iPhone, whatever iPhone this is, shoots non-standard video formats.
Cheesenightmare wrote:
I think an iPad is enough machine for this 😉
AHT is the Apple Hardware test.
Ha…and aha!
Sometimes I do transcode, sometimes not. The problem happens intermittantly regaurdless and I started to suspect that it was h.264 that was given issues most of the time so I shot some test video on an iPhone. In the original post the video I linked to shows footage that was *not* transcoded.
Coming from an iPhone means nothing, especially as the iPhone, whatever iPhone this is, shoots non-standard video formats.
An iPhone 4s shooting h.264 1080p .mov
In the world of tapeless media, this is pretty standard.
I understand that H.264 is a long GOP format, and not optimized for editing hence the desirability to transcode to an intraframe codec such as ProRes. However, one of the features of FCPX is that it is designed to handle h.264 footage because a lot of video is shot that way these days.
Coming from an iPhone does not mean nothing. It means the company that designed the software capable of editing h.264 also designed the software and hardware that shot the footage in h.264 format. It means we can expect that at least some thought was put into them playing well together. It means that if I shoot some test video on an iPhone, put in on an iMac running FCPX without filters I should be able to expect smooth playback all else being equal.
Can I add to this a curious point - it isn't just playback that slows. My mouse sticks and lags on screen when this happens too.
I'll try some of your helpful suggestions Jakob thank you 🙂
Stuttering Playback on iMac
