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Johnny
07-30-2005, 07:36 AM
I'm working on an animation which will be HD (720p) and which I'll edit in FC studio. I'm wondering whether h.264 is a good codec to work in while editing in Final Cut studio?

specifically, I'm trying to decide which codec for working in FC5 that is best for quality, but that also gives me fluid playback; on a Dual 2ghz G5, 720p24 can be hesitant, and downright jerky.

Now, the Apple Intermediate Codec plays smoothly and looks good, but I'm not sure if this is a good codec to use compared to the others.

the goal here is to produce a 720p24 movie for viewing specifically on LCD monitors, both computer and HD.

J

munky
07-30-2005, 11:02 AM
Hi there,

you might find an answer at www.hdforindies.com or www.creativecow.net

regards

paul

toby
07-30-2005, 08:53 PM
I played with h264 a little and it looks like you can't get lossless compression with it, so I recommend keeping everything in Animation until you do the final output - I was able to play the animation codec smoothly at 1440x960.

avkills
07-30-2005, 10:15 PM
I suggest keeping the Animation codec as well. If you do not need to do any compositing with Alpha channels, then you could also use the Apple Uncompressed HD codecs or even a DVC-PRO HD codec and then import that into FCP or Compressor and then compress to H.264.

H.264 is not really meant to be a working format, just a delivery format like MPEG-2 or MPEG-4.

-mark

Johnny
07-31-2005, 08:53 AM
I suggest keeping the Animation codec as well. If you do not need to do any compositing with Alpha channels, then you could also use the Apple Uncompressed HD codecs or even a DVC-PRO HD codec and then import that into FCP or Compressor and then compress to H.264.



Well, why is it that my stuff looks like garbage when I use the Animation codec? Is animation best suited for large areas of flat color, as opposed to scenes with lots of subtle gradations?

J

toby
07-31-2005, 01:12 PM
You have to use it with 100% quality.

If you want a compromise, the JPG2000 codec makes your files about 1/3 the size of animation, 99% lossless, (and now carries an Alpha!) but playback suffers -

Johnny
07-31-2005, 03:36 PM
You have to use it with 100% quality.


OK..I'm getting better results - higher quality, and the playback isn't bad in FCP if my Canvas is at 70% or smaller.

Will this animation codec pass all of the quality from the rendered frames? I'm rendering out at 16-bpc, and each frame is 14.1MB, yet the resulting Animation clip is only 258 MB, not the some 4GB represented by that image sequence.

Am I right in assuming that a lot of info is being chucked in the exporting as Animation?

CMD I in QT 7 reveals millions of color, so it seems that my color depth is preserved...

J

toby
07-31-2005, 05:07 PM
The only difference between Animation at 100% quality and uncompressed frames is the file size. It's the industry standard, you can re-encode with the Animation codec infinitely with no quality loss. If you need fast playback and highest quality, it's the best way to go.

riki
07-31-2005, 06:08 PM
I've noticed though with Animation codec I get lots of banding in gradients, even with quality set to the highest possible value.

Johnny
07-31-2005, 07:50 PM
I've noticed though with Animation codec I get lots of banding in gradients, even with quality set to the highest possible value.


what do you do, then? do you prefer another lossless codec?

and do people trying to do HD animation always employ RAIDs because the codecs which aren't lossy demand the data throughput provided by them?

J

riki
07-31-2005, 07:56 PM
I don't have a lot of experience in this area, and I'm not doing any post work, not at that stage yet, but seem to get the best results with Sorenson3.

Johnny
07-31-2005, 07:59 PM
OK..I'll give sorensen 3 a try.

BTW, when you used animation, was it with millions of colors, or millions +?

I noticed more banding when I used millions + than with just millions.

J

riki
07-31-2005, 08:26 PM
Okay now I do feel like a complete idiot :(

I just realised I did the last 'Animation' test in 1000s of colours, hence the banding. The quality of Millions+ looks amazing, I'm not getting any banding with that, but the file sizes are much larger. I'm guessing 'Animation' must be a lossless format, suitable for post work?

The small title sequence that I've been doing the tests on came out at 16Mb with the above settings (Animation, High Quality, Millions+). In comparission Sorenson3 was only 500k with the higest possible quality settings. So again just guessing, but I'm assuming Sorenson3 must be more of a lossy delivery format. Maybe someone esle can clarify.

toby
07-31-2005, 08:26 PM
Here's 2 good ways to compare a codec to the original and to other codecs :

1. Open both movies in QT, size them to full screen then back to original size. This puts them in exactly the same spot. Cycle between the 2 movies back and forth while you look for any change.

2. Export a single frame from your encoded movie, open it and it's corresponding uncompressed frame in Photoshop, layer them together, and change the top layer's blend mode to Difference. Any differences will show up as colored pixels, everything that's identical will be black.

toby
07-31-2005, 08:40 PM
Yea I was pretty :question: at what you said about Animation and Sorenson! Sorenson is indeed a delivery codec, I still think it's the best one, until most PC's have H264 anyway -

Johnny
07-31-2005, 08:44 PM
Okay now I do feel like a complete idiot :(

I just realised I did the last 'Animation' test in 1000s of colours, hence the banding. The quality of Millions+ looks amazing, I'm not getting any banding with that, but the file sizes are much larger. I'm guessing 'Animation' must be a lossless format, suitable for post work?


yeah, at 100% or "Best" quality. don't feel too bad; I did the same thing,and when I saw the nasty banding, abandonded Animation until Toby's post tonight.

But, all of these codecs have their caveats, such as "Animation does best with long horizontal lines and is lossless at 100%."

So, does that mean that animation with out so many horizontal lines will have issues, or that you're good as long as you select "100%" quality!?

BTW..I found this page..sort of a good thing to tuck away, perhaps:
http://people.csail.mit.edu/tbuehler/video/codecs/quicktime.html#anim

J

toby
07-31-2005, 09:09 PM
He's not talking about long lines that you can see, like power lines or something, he's talking about lines of video/pixels that are the same color, and that it can compress this video to a smaller file size. The quality is always 100% lossless.

Johnny
07-31-2005, 09:12 PM
OK..that's what I thought it meant..so, where possible, it compresses those pixels' data; otherwise, lossless?

J

toby
07-31-2005, 11:56 PM
It's compressed and lossless, no matter how well or what the file size.

stib
12-13-2005, 11:15 PM
Okay now I do feel like a complete idiot :(

I just realised I did the last 'Animation' test in 1000s of colours, hence the banding. The quality of Millions+ looks amazing, I'm not getting any banding with that, but the file sizes are much larger.

FYI
Millions means 24 bits per pixel (ie 2^24 colours, which = ..er.. millions). Animation is an RGB codec so those 24 bits are divided into three 8 bit channels for R, G & B*

The "+" in millions+ means +alpha. So you've got three 8-bit colour channels + one 8-bit alpha channel (ie 256 levels of alpha). So millions+ means 32 bits per pixel. This means if you're rendering something with no Alpha channel you can save one third the file size by rendering out at millions, not millions+.

If file size is a problem for say long term storage, moving things around on discs or over networks you'll find that animation files usually zip down a lot when you compress the files (This is file compression, not image compression, so it is lossless, once you've decompressed. But you can't play back a zip file, obviously).

This difference between image compression and file compression is how Animation manages to be both lossless and compressed at the same time - it uses some file compression to reduce file size, but unlike image compression, where less noticeable parts of the image are thrown away, the resultant image in files compressed with animation is a pixel-for-pixel exact copy of the original. The reason it works well on flat colour is that the file compression algorithm it uses works well where there are lots of repeating sequences (I think it might be LZW compression, like tiffs, but I might be wrong).

*Are there lossless codecs like animation which use YUV? one that used say, 12 bits for Y and 6 each of U and V would make more sense.. maybe..?

toby
12-14-2005, 12:15 AM
I'm rendering out at 16-bpc, and each frame is 14.1MB, yet the resulting Animation clip is only 258 MB, not the some 4GB represented by that image sequence.

J
Crap! I missed this! Animation won't save 16bpc, but unless you're doing color-correction in post, it doesn't do you any good anyway. The only video compression I know of that supports 16bpc is Microcosm. If you can part with $100, it's worth it - files are much smaller than Animation even at higher bit-depths.

Johnny
12-14-2005, 04:23 AM
Crap! I missed this! Animation won't save 16bpc, but unless you're doing color-correction in post, it doesn't do you any good anyway...


this is *great* timing..just about to begin rendering my little movie..this bit of info will save me some churning time as I convert those clips to Animation!

thanks!

J