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XDCAM EX 1 hr timeline very slow to export to QT moviePosted by jwatt
I have a one hour XDCAM EX program that I'm exporting to a self contained QT movie. The dialog box tells me it's going to take 8 hours. In the past this same process normally takes less than an hour. Any ideas what the problem may be?
Dual quad core Mac Pro/10 gigs ram/Video drive is apple raid (is a little full)/ Kona 3 card. Thx for any suggestions...jw
XDCAM is a long-GOP acquisition format and not optimal for mastering. You should change your sequence compressor to uncompressed or ProRes and then export. Final Cut will have to render your whole timeline before it can export your master Quicktime, but the process of rendering and exporting will take less time than conforming and exporting to XDCAM.
you say:
in the past was it XDCAM EX as well? or was DV or something like that? i rendered out a 45min live concert in DVCPROHD on a similar macpro and it took about 3 hours... so i dont think youre too far out of the realm of reality...
Thanks for the prompt replies, however we have had very good success and have read a number of posts that agree that staying in the XDCAM EX forma, but setting the render to pro res is the recommended way to edit this format. I've done it both ways and don't agree. We've edited 12, 1 hour shows staying in the XDCAM EX long GOP format, but with render set to Pro Res and they've worked great.
This is an identical timeline to the other dozen programs, the only difference is the long export time.
Valid observation, and you may have found the problem. This program is quite similar to the others I've done in the past. Same style, pacing, etc., but the one thing there are more of here are traveling mattes, about 2 dozen, which may indeed be causing the slow down.
there's a lot of on camera presentation cut into the show from our safari guide in his land cruiser so I used a custom gradient, mask shape and feather to darken the background and bring up his face. thx...jw
It depends on the complexity of the filters that you are applying. A brightness and contrast filter will render a lot faster than for example, a film effect. This applies to anything, from DvcproHD to DV.
>We've edited 12, 1 hour shows staying in the XDCAM EX long GOP format, but with render set to >Pro Res and they've worked great. Yup. Whatever doesn't need rendering won't need a render for playback, whatever needs rendering, does not need to be conformed back to long GOP, so this saves time. If everything needs rendering, it doesn't make a difference if you're cutting in a ProRes timeline or an XDCAM EX timeline with render set to ProRes. Also, go to Render settings- set render quality to 8 bits. The trade off is quality, but it renders quite a bit faster than rendering in high precision YUV. www.strypesinpost.com
? when working with Long Gop media in a long Gop sequence and rendering in ProRes you will end up with a fully rendered Timeline, I mean... there is at least a little Color Correction on every cut . (let's assume it).
at this time I will have a Long Gop sequence linked to a bunch of ProRes render files. Now I want to have a ProRes timeline to export. even if Strypes says : If everything needs rendering, it doesn't make a difference if you're cutting in a ProRes timeline or an XDCAM EX timeline with render set to ProRes. I am not comfortable with it. Maybe I am wrong. but if I change my sequence settings to ProRes ... BAM ! all red. The same if I copy & paste all the cuts in a new ProRes Timeline. wouldn't there be a way to do this and keep the renders ? ? alternative way would be to edit the long Gop clips in a ProRes Timeline and enjoy the real time open format sequence until you render ... (it's just a light grey bar above) That's what I do. Witch one do you prefer ? Of course: wouldn't it be nice to Log and transfer XdCam Ex material as ProRes ? we can do it with AvcHD, why not ProRes from XdCam Ex ? ? ?
>but if I change my sequence settings to ProRes ... BAM ! all red.
Ah. I meant during editing. Exporting will mean everything will need a render. If you convert everything to ProRes, exporting time will be a lot faster, especially if you do not have filters on every clip. However, if you do have a CC filter on every clip, everything will still require a render. I haven't tested this yet, but I believe rendering XDCAM EX will render to ProRes in around the same amount of time as rendering ProRes natively. The trade off with working native with long GOP formats is storage. >Of course: wouldn't it be nice to Log and transfer XdCam Ex material as ProRes ? I was hoping that we can work AVCHD like we can XDCAM EX, where native editing is an option, and we can render out to ProRes instead, kinda like working with RED footage. www.strypesinpost.com
Let's have it crystal clear
If I edit long GOP media in a long GOP sequence and render in ProRes, therefore end up with a fully rendered Timeline. when it's export time I have to take the hit of the never ending re-conforming process in long Gop because it is still a long Gop sequence under the hood ? Is this a right assumption ?
Yup, that's correct, although slightly incomplete.
If you edit in an I-frame timeline (ProRes, DVCPRO, DV, any other I-frame format) and render it all, when you tell Final Cut to export it will literally just copy the frames from either the source clips or the render files into a Quicktime movie for you. There's very little math that has to happen. But if you edit HDV or XDCAM with ProRes rendering turned on, before Final Cut exports your timeline it has to re-render everything in your timeline format, which is time consuming, in addition to having to conform your timeline to the long-GOP format of your choice. "Conforming" in this context means something different from "conforming" in any other post context. In this context, "conforming" means decoding and re-encoding frames in order to give your finished Quicktime the correct GOP structure. If you cut in 70 frames from one shot and then 215 frames from another, even though you don't have to render to play back in real time, Final Cut still has to decode the second shot and re-encode it to write out a stream a closed, 15-frame GOPs in your finished Quicktime. So basically Final Cut has to re-encode your entire timeline (more or less) when you export to a GOP format. Note that this also applies to printing to tape in a GOP format; you can't get away from the necessity of re-encoding the frames into the correct GOP structure. That's why I-frame editing is just inherently so much less time-consuming: Because any frame can go anywhere in the finished Quicktime or on the finished tape, so frames that are compressed in the camera and don't have to be rendered by Final Cut are never compressed again. Yes, computers are getting faster. I'm sure someday computers will be fast enough not just to play back multiple streams of GOP-encoded footage in real time, but also to conform (i.e., decode and re-encode) those streams for real-time or faster-than-real-time lay-off and export. But we're not there yet.
Jeff,
Thank you very much for your concise and very understandable explanation. It explains why edit to tape also takes an inordinately longer time than our DVCPRO HD edit to tape sessions. Makes a lot of sense. I guess my next quandry is to just start with a ProRes HQ timeline or stay with the XDCAM EX long gop until export time. Thanks again, your insight is greatly appreciated. jw
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