View Full Version : Do Sequence Settings in Premiere actually matter?


John Hewat
June 9th, 2011, 02:56 AM
I've collated a hundred hours of H264 documentary footage from a 7D using Premiere and have already started editing some of it.

Now... I get some advice that says "transcode to ProRes" and some that says "just edit the 264 footage" (if you have an opinion on this please feel free to advise me) but whatever the case, if I do transcode to ProRes, and I re-link all the media in the project to the ProRes files, won't the sequence settings be incorrect?

And then I think, so what? Does the sequence setting I choose serve any more purpose than making sure the frame rate, image size are consistent and of course determining the quality/size/rate of the rendered preview files?

I practiced importing a ProRes file into my H264 timeline and it scrubbed just fine; faster than the H264 footage!

When I actually come to exporting the product at the end, I will select whatever is required, so I fail to see the connection between Sequence Settings and final output.

Of course, at some point, I am going to have to give this project to a sound editor and a colorist and I'm told they will most likely want a ProRes project. But I'm a little in the dark about how to deliver it to them.

Ann Bens
June 9th, 2011, 03:22 AM
Your sequences settings should always match your footage regardless the output format.

Bart Walczak
June 9th, 2011, 04:01 AM
Sequence settings influence the following:
- the resolution of the project (eg. 1920x1080 square pixels)
- the frame rate and field interpolation (eg. 50i upper field first)
- monitoring on external card (important for interlaced footage, so that you don't get the switched fields effect during monitoring)
- rendering codec and quality (preview quality)

To some extent also export is dependent on sequence settings. If you have any titles or stills that you add in Premiere, then it is vital that the field order of the sequence is the same as your export setting - not necessarily your footage! Otherwise the titles and footage will export deinterlaced, and you will lose resolution. It might be only an issue with BlackMagic Design cards, but I got consistently worse quality when I exported BMD uncompressed sequence straight to DV, where the order of fields is switched, instead of exporting to uncompressed and then converting the output file to DV.

Therefore I would argue actually against matching footage with sequence settings, and for matching sequence settings to your export settings or going for a responsive good quality intermediary, so that you can use preview renders for output.

As far as converting to ProRes vs not - depends on the computer that you work on. I have a Mac 1,1, and AVCHD is something that is almost uneditable here, so I have to transcode. When you will be exporting project for other people, it's perhaps good to have the footage transcoded. You will have to provide either an EDL, AAF or FCP XML file to them. It's best to check it out with them what kind of format they support.

Bogdan Nicolau
June 9th, 2011, 04:34 AM
If you work only inside Adobe Creative Suite, I can't see the reason to transcode to ProRes, the only gain I think it would be, that ProRes are not so heavy on the processor than h264, which are highly compressed files.If you have an hexacore I7 you'll play just fine the h264 from the 7D.

About the sequence settings, not all of them would be so important, so your files are Full HD @1920 x1080, progressive at 23.976 or 29.97 fps.If you render the timeline prior to export and use the rendered files to speed up the final export, then I think it will be safe to respect the correct settings.

However you can change the settings in the Export to Media window, or to correct them about the fields order if you work with interlaced files.

About the part of delivering the final output to a colorist it would be logical, i think, to deliver the project on separate clips as an XML file for working precisely with every cut, than to sent it as a raw file.

However, ProRes is considered somehow lossless, similar to uncompressed avi but with a smaller size.One important thing is that with every compression you lose information, even with an so called lossless format.

Maybe that's the main point with Adobe CS, you don't need to export/compress, you have a final file that is very close to the original material regarding image quality.

John Hewat
June 9th, 2011, 06:10 AM
Thanks everyone,

It does sound very much like there's no one right tool, just a bunch of options and I can pick the one that suits me and my system the best?

As for transcoding to be nice to your CPU, I'm finding that the CPU of my 2011 MacBook Pro is not struggling, but the e-SATA drives are really slowing the process.

Doesn't that mean that I am better off with the smaller file sizes of the H264 footage than I would be with the larger ProRes files?

I have also been told that H264 editing is a bad idea because it is not frame accurate; is this not the case?

Ultimately, if I decide to go to ProRes, I would then be importing the ProRes footage into the H264 timelines, but because the frame rate & resolution match the intended output, and because I don't use an external card, and provided I don't select to use the Preview Files on export, I'm totally safe?

One final question: I am considering transcoding the H264 files to ProRes422(Proxy) files, because portability and storage is an issue for me at the moment, so keeping the file sizes down is a priority for me.

That means I'll be re-linking the project media to ProRes Proxy files, then doing the edit.

At the end, before I export, I can simply re-link the media again to my original H264 files. Correct?

Thanks again,

-- John

Bart Walczak
June 9th, 2011, 07:54 AM
ProRes proxy is 45 Mbps, which most likely is about 2.5 times the size of your H264 files. It may stress your harddrives a little bit, but eSata throughput is quite big - 1.5 or 3.0 Gbps, so it will be more likely that your hard drive will be the limitation here (I guess you're getting about 100-120 Mbps of reading performance from a single 7200 rpm drive). This gives you about 2 ProRes or 4 H264 streams in real time. If performance is good, then stick to the H264.

If you will be exporting XML, EDL or AAF, then you only need to take care about the frame rate in the sequence. Codecs and other stuff is unimportant in the long run, because you won't be exporting it to a single file.

However if you will export the project as a single file, then yes, you can edit with proxy files and then relink with the new ones without a problem.

Bogdan Nicolau
June 9th, 2011, 07:59 AM
John,

If you're confused about various file types and their properties ex. DV, HDV, HD and PAL, NTSC or FILM , also resolutions, use one valuable tool called "Media Info" or for Mac, "Media Inspector" :

Media Inspector for Mac :: Multimedia file analyzer for the Macintosh (http://mediainspector.massanti.com/)

You just right click one one particular clip and it gives you all the information you need about the video and audio track.There's also important to know basic things about the most used containers like mpeg, avi, vob, mp4, mov.

The workaround of making proxy files looks right for your configuration.In theory (never tried) it should work as advertised, in fact I saw a tutorial about this tehnique, several years ago; make smaller resolution ProRes files (like 640x480 ), edit them and before final export relink the original h264 files.

About the theory that h264 files are not frame accurate, i beleive that it's not true, however if one particular video file it's not frame accurate, it will retain the same bad properties after it will be transcoded in another format, resolution and codec.The same video and audio information re wrapped with different codec under different container.

John Hewat
June 9th, 2011, 08:16 AM
ProRes proxy is 45 Mbps, which most likely is about 2.5 times the size of your H264 files. It may stress your harddrives a little... This gives you about 2 ProRes or 4 H264 streams in real time. If performance is good, then stick to the H264.

According to my tests, the Proxy files are coming out slightly smaller than the H264 files.

If they are smaller, they will presumably stress the HDD less and they will undoubtedly be easier on the CPU. In which case, transcoding before editing sounds like a good idea, right? But if they are larger files than the H264 originals, then sticking with the H264 files throughout the edit sounds like a better idea?

Also, Bogdan, isn't it advisable to keep the proxy files atthe same resolution as the originals/intended outputs? Or doesn't that matter either?

Bogdan Nicolau
June 9th, 2011, 08:31 AM
No, the proxy files are resolution independent, the smaller, less disk and CPU utilisation.One bad think it would be that you lose the original video quality and crispness during editing.

Robert Baynosa
June 9th, 2011, 08:00 PM
ive always matched sequence setting to footage as ann suggested. on fact ppro has an automate sequence to footage setting.

but i get barts logic. using ppro's preview renders for final encoding by using sequences that have the same settings as your final encode/export could be a major timesaver.

my question is this. if your playback setting is set to one half or less and you render effects in sequence for previews, would that still help in final encode/export? or do you have to set playback in full for your preview renders to be of any use?

John Hewat
June 9th, 2011, 09:09 PM
I could be wrong but I don't think playback resolution affects the render quality of the preview files.

So far I haven't had to render anything in Premiere, even when I add effects and manipulate the video files enough to changethe yellow line to red, playback is still (mostly) very smooth.

That's dealing with H.264 files. I haven't re-linked to the ProRes proxy files yet because Mpeg Streamclip is still creating all the thousands of files.

Even so, if I do have to render using the low quality ProRes footage, I can just tell the final export at the end not to use the preview files (because I'll have re-linked back to the original H.264 files at that point).

I'm not fussed about saving time at that final stage of the process, only with ensuring a smooth, crash/freeze/lag free editing experience.

So at this stage I've already:

1. Started H.264 sequences
2. Organized the footage accordingly
3. Started editing

Now I'm going to:
4. Transcode to low quality ProRes Proxies
5. Re-link the media tothe ProRes files
6. Edit until complete
7. Re-link the media to original H.264 files
8. Export (without using preview files)

Does this sound reasonable?

I do still have the option of using the ProRes files to determine the sequence settings of all the other sequences I'm going to have to create to get this done. Is that a better idea? Or am I advised to keep the sequence settings in line withthe target output rather than the temporary media files?

Bogdan Nicolau
June 10th, 2011, 01:06 AM
Your plan sounds reasonable. About the timeline settings, do it for your original h264 files at 1920x1080, import all the proxy files in the bin, then import them in the timeline, select all the files and right click - scale to frame size.

John Hewat
June 10th, 2011, 01:42 AM
Thanks Bogdan,

I've actually already started the process of creating the proxy files, which is going to take at least 24 hours for both my computers to do it. And unfortunately I maintained the resolution at 1920x1080. The file sizes are smaller than the H.264 files so they are shrunk but I wish I'd made them smaller. Hopefully the edit will go ok nonetheless. Thanks again!

Bogdan Nicolau
June 10th, 2011, 05:27 AM
Good luck !!!

I hope that you'll obtain a good balance between the resolution of the proxy files and your system performace for a decent edit.

John Hewat
June 10th, 2011, 11:16 PM
Me too! Your advice has been great and will help me a lot.

My next question about this whole process is a curve ball I did not see coming and may be a problem and ruin my day or may be no big deal at all.

I posted the question here: in the Final Cut forum (http://www.dvinfo.net/forum/final-cut-suite/497026-7d-h-264-prores-files-timecode-question.html) about whether Mpeg Streamclip has done the transcode to ProRes correctly or whether I need to go back and start it again in Compressor...

Bogdan Nicolau
June 11th, 2011, 12:31 AM
Good question regarding the timecode and the step about relinking the original files.If i'd be in your shoes, i should make a little test: drop some proxyes on the timeline, cut them in a way to remember, maybe when in the frame appear some important objects, write these cuts down and finally relink the h264 files and check visually that premiere done its job fine.Maybe a final render and another check would guarantee you that everything's hopefully allright.

I was thinking about doing all the big steps and checking that Premiere is able to relink the footage based on every particular clip timecode (hopefully).

John Hewat
June 11th, 2011, 08:03 AM
Thanks Bogdan,

I'll do the tests as soon as I can. I am figuring the best way to re-link the (approximately) 4000 files will be to simply disconnect the HDDs with the proxies on them and open Premiere and when it asks where the files are, just navigate to te H.264 files. I assume it will work.

I'll do the test with just one or two files of course and see how I go.

Thanks again!!

Steve Oakley
June 21st, 2011, 12:42 AM
just edit native and skip the proxy files. you are setting yourself up for a world of hurt down the road. you are making things WAY more complex then they need to be.

if you are having stuttering with playback, its probably NOT your drives, but your CPU / RAM / other factors. h264 data rate is really low.