file compression - final cut pro

[mfparcher]

I am fairly new to final cut pro and when I finalized a project the other day (about 15 min) in HI RES (4444 I think) the final file came out to about 20 GB. Needless to say, I had to compress. I am getting ready to make a short film with a running time of about 30 min and I would like to know if the compression will take away from the HD quality, and if it will, are there any other options?

Thanks!

 

[Will Vincent]

I would assume you didn't shoot/acquire that footage at anywhere near the color depth you apparently rendered it at, so while rendering to "HI RES (4444)" doesn't degrade your image in any noticeable way, it's also a massive waste of space.

Most likely you won't need anything better than a 442 color depth, I would think prores should be fine for pretty much everything up through final output, but I'm not a mac guy, so I can't really get into codec specifics like that.

The bottom line though is that yes compression will degrade the signal, but good compression won't degrade the signal in a visible way... and you're best bet is to work with the smallest amount of compression and/or best (quality, not size) compression method you have available minimizing signal loss as much as possible until final render, which depending on your delivery format will likely be some variation of mpeg 2 or mpeg 4.

 

[mfparcher]

Thanks, Will. Much appreciated.

 

[Sweetie]

If you're talking about output after you've finished the project, then you should compress it. Normally codecs are lossy, meaning the size benefits you get will mean you will lose some quality. The question isn't whether there is a loss, but whether you can notice.

If you're talking about footage you're now about to edit with, it'll depend on what you're going to do with it. If you're altering the images, using some chroma key etc, then your compression can have an effect on the quality.

 

[friolator]

I am fairly new to final cut pro and when I finalized a project the other day (about 15 min) in HI RES (4444 I think) the final file came out to about 20 GB. Needless to say, I had to compress. I am getting ready to make a short film with a running time of about 30 min and I would like to know if the compression will take away from the HD quality, and if it will, are there any other options?

"Compression" means lots of things, and some compression techniques are better than others. Avid DNxHD or ProRes HQ are pretty much equivalent in terms of quality, and are very high quality at that - you probably won't notice any real loss in picture quality with them. 4444 is overkill unless your source files are RGB to begin with, which they're probably not.

The general workflow I recommend to our clients is this: Figure out what your output requirements will be before you even load footage into your edit system. This means thinking about the frame rate, resolution, codec, etc. and about what deliverable formats might be required at the end. Decisions you make at the beginning affect what you can do near the end, so it's important to get this part right.

For example - if you have a 1920x1080p 23.98fps source and you want to go to Blu-ray and to DVD, I might recommend first converting all of your source video to ProRes 422 HQ at 1920x1080/23.98. Then bring this into FCP and edit the ProRes files. If you're working in HDV or something, you don't want to be editing these files in the edit system as you'll lose quality at most of your cuts or transitions (cuts actually have to be rendered in this format, and that's lossy). Once you've done your edits (at 23.98) and you've finalized the film, I'd render out a final HD master, also as a ProRes HQ file. From this you can easily make an NTSC DVD with 3:2 pulldown, convert to 25fps for PAL DVD if you want, make a Blu-ray at 23.98 (which will play worldwide), or downconvert for web upload where the frame rate is less of an issue.

By the way, 20GB is nothing! Try working with an uncompressed feature-length 10 Bit Quicktime. that'll clock in at just under a Terabyte and isn't playable on anything but a fast RAID. Consider getting an external drive (Firewire 800 at minimum, not USB. eSATA or Thunderbolt are best if you can do it) that contains your source materials, and a second drive to render to. Make sure each is connected to separate ports on the computer, not daisy chained. This will speed things up immensely when working with bigger files.

-perry

 

[ItDonnedOnMe]

the final file came out to about 20 GB. Needless to say, I had to compress.

You say you had to compress, but not what you had to compress for. If you just need to save space on your hard drive you can try mastering to one of the lower quality ProRes formats. Based on your running time and file size I'd guess you used ProRes HQ (not 4444). Standard ProRes will drop your file size to 15GB, LT will be about 10GB. You may or may not see much difference in quality depending on your source material, but even with LT the quality loss should be relatively minor unless you started with a very high quality source or are using a lot of graphics.

If you're compressing for delivery then it's a different matter. You'll probably end up using h.264 for online delivery and possibly MPEG2 for DVD, but you'll need to determine your target bit rate for either situation and that depends entirely on how you plan to get it to the viewer.