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Johnny
03-24-2004, 12:49 PM
I just tried Pixlet for the first time on a 400 MB Quicktime file, and ended up with an equally-good file of merely 37 MB!

Before I get busy and apply Pixlet compression to all of the sequences I'm working with for FCP, are there any downsides I ought to be aware of?

Is Pixlet best for compressing a finished video, or is it also good for compressing source video which is still being used in in-progress FCP projects?

thanks!

J

toby
03-24-2004, 01:29 PM
hey - what compression was on the qt before you exported the Pixlet version? Uncompressed? Did you use keyframes? Looking forward to playing with it -

Johnny
03-24-2004, 02:26 PM
Originally posted by toby
hey - what compression was on the qt before you exported the Pixlet version? Uncompressed? Did you use keyframes? Looking forward to playing with it -

I finished up doing a screamernet segment this morning...that's the source of my 400mb sequence...I used QT Pro to make a self-contained movie..the choice you get after opening Image Sequence, then hitting Save. From LW, I saved each frame as LW_PShop32(.psd), NTSC size 720 x 486.

Found my way to Apple Pixlet, which you reveal by clicking the Options button after selecting Export.

I chose "Best" quality, and hit OK...that was really all there was to it; not a lot of settings involved, at least not the way I did this.

One reason for my original post is that, after searching Google for how to utilize Pixlet, I came upon a discussion in which some guy used Pixlet, and wound up with a much larger file than he started with.

Apple provides no how-to on their site, so I wanted to ask those experienced with Pixlet.

J

Ed M.
03-24-2004, 02:59 PM
I think this is Beam's area. However, I read that some in the pro-community believe that Pixlet is nothing more than hype; what do you guys think? Ted, Beam? Check it out:

http://www.creativecow.net/forum/read_post.php?postid=107962549992138&forumid=8

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Ed

eblu
03-24-2004, 03:31 PM
pixlet seems streamlined.
it doesn't support alpha channels, or quality control (100 percent is all you get). Its a straightforward one application codec.

from apple:
"Pixlet is the first studio-grade codec for filmmakers, and itís available exclusively in Mac OS X v10.3 Panther. Tuned for use with high-definition source, it allows digital film frames to play back in real time on any 1Ghz G4.
"

I'm guessing that this is designed not to eliminate data, but to make playback realtime (from disk not ram), and maintain quality. Most of the time when you find that re-compressing something adds to the file size its usually due to color conversion issues (banding), or noise in the channel, noise generated by the original compression, is considered detail and added to the frame.

I suspect that this is not the case with Johnny. he went from a pristene source to a "pristene" source.
Pixlet is probably a Lossless compressor, so if you have a lot of flat color in your movie it will do a good job. Not a significantly better job than everything else. The gotcha comes in when you have a film sized frame on a 1 Ghz g4... it will play in realtime, at full res. Not something to sneeze at.

as for compression:
I took the "Hack" tv show open which I happen to have in its original form as a Lossless Hidef quicktime, and converted it to pixlet in AE.

the original is about 850 megabytes.
the pixlet version is 677 megabytes.

the original stutters and fails to play back fully on my dual 1 gig g4 at half res (my monitor is too small to see the whole thing)
the pixlet version stutters, but plays completely, at half res. there is no visible difference between the two.


is pixlet a good codec for elements? probably not. if you use alphas, or have a dedicated hardware setup (black magic, digital voodoo) then pixlet doesnt meet your needs.
But if you need to get a finished composite to a co-worker who is also on Panther, in hidef or better, then this is a no-brainer solution that you might want to check out.

wanna save space with your renders? check out the PNG format.

Ed M.
03-24-2004, 03:54 PM
OK, then I'm guessing that the guys on the creativecow forum are missing the picture? pun intended ;)

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Ed

Beamtracer
03-24-2004, 04:25 PM
Originally posted by Ed M.
OK, then I'm guessing that the guys on the creativecow forum are missing the picture? pun intended ;) Most of the comments on creative cow did miss the picture.

Pixlet is for us. It's the 3D animator's codec.

My Lightwave workflow is all 16bpc. I made a tutorial about how to do this, which is further down this forum if you want to search for it.

My Lightwave animations begin life as 16bpc PSD files. These have enormous file sizes, so the first thing I do is translate them to a 16bpc Quicktime. There are only two codecs that can do this... Microcosm and Pixlet.

People who speak of Pixlet in the same breath as JPEG, Windows Media 9 and MPEG-2 are all missing the point. The two main features of Pixlet are that it's:

1. 16bpc
2. Lossless

It's perfect for elements and for archiving. You keep 100% of the original quality. Playback speed is irrelevant for this purpose.

I don't know why it's not supporting alpha channels. If you're using a compositing app like After Effects you can just render off your alpha as a separate matte.

Johnny
03-24-2004, 04:32 PM
Thanks, Beam...good to know. Is it easy (or even important) to explain how Pixlet makes things so small with no degradation?

IOW, what's all the data it chucks as it compresses?

J

Ed M.
03-24-2004, 05:12 PM
Someone care explaining this to the CreativeCow guys? ;) Thanks Beam, Ted.

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Ed

Beamtracer
03-24-2004, 06:51 PM
By the way, Lightwave only supports 8bpc Quicktimes. It does not support 16bpc Quicktimes.


I've posted a thread in the Feature Requests forum. If you think it's important to gain 16bpc support, please read this thread and add your voice.

Here:
http://vbulletin.newtek.com/showthread.php?s=&threadid=20186

jro2a
03-25-2004, 02:12 PM
PIXLET RULES........... it just does......


Jim R.

james767
03-25-2004, 02:49 PM
what is 16bpc?




Originally posted by Beamtracer
By the way, Lightwave only supports 8bpc Quicktimes. It does not support 16bpc Quicktimes.


I've posted a thread in the Feature Requests forum. If you think it's important to gain 16bpc support, please read this thread and add your voice.

Here:
http://vbulletin.newtek.com/showthread.php?s=&threadid=20186

Beamtracer
03-25-2004, 03:00 PM
Originally posted by james767
what is 16bpc? Here's a link to my earlier tutorial covering what 16bpc is:
http://vbulletin.newtek.com/showthread.php?s=&threadid=16608


As I said before, Lightwave cannot render to Pixlet in 16bpc mode. LW can only read and write 8bpc Quicktimes. If you want 16bpc support, add your comment to this feature request thread:
http://vbulletin.newtek.com/showthread.php?s=&threadid=20186

fxgeek
03-25-2004, 04:52 PM
Pixlet does support a Quality setting. However you really should leave it on 100%

It is ideal for delivering content where bandwidth is an issue. While it is a losless codec, you can convert it back to uncompressed on the recieving end for editing playout. Ive done tests at our facility converting to and from Digital Voodoo uncompressed quicktime files and there is no visible loss in quality on a grade 1 Production Monitor.

Despite what is said on that Creative Cow forum in my opinion and based on tests I have conducted I can say that it is far FAR superior to motion Jpeg codec for image quality.

As for alpha channel support, I think the idea behind Pixlet is that it would playback in realtime with deep colour support and maybe Alpha support would affect that.

Beamtracer
03-25-2004, 06:54 PM
Pixlet's strength is its 16bpc color depth and the fact that it's lossless.

If you just want to play back video on your desktop, or distribute video for others to preview, it's much better to use a "lossy" video codec. Lossy video codecs will have small file sizes, resulting in smooth playback. The quality of lossy codecs is not as good as the original, but the average viewer wouldn't notice the difference. Great for posting video on the web.

Lossy codecs:
JPEG, motion JPEG, MPEG 1, 2 & 4, DivX, Windows Media 9.

Uncompressed codecs keep every bit of information, but their file sizes are humongously massive. They are not used much by the general public.

Uncompressed codecs:
Avid Meridien (used by professional video people)
Black Magic (Decklink) video codec
Digital Voodoo Uncompressed
Quicktime "none" codec
Quicktime "video" codec (I think)

Some codecs can reduce the file size, but don't degrade the picture at all. These use "lossless compression" which combines the ability to reduce file sizes with the pristine image quality of Uncompressed codecs.

Lossless codecs:
Quicktime "Animation" (8bpc only)
Pixlet (8bpc and 16bpc)
Microcosm (8bpc and 16bpc)


So if you want absolutely pristine images without any image degradation or artifacts, I recommend using one of the "lossless" codecs above.

Pixlet is the most efficient of the lossless codecs. This is because it uses new wavelet technology and other methods to reduce the file size without reducing image quality.

toby
03-25-2004, 09:54 PM
Originally posted by Beamtracer

As I said before, Lightwave cannot render to Pixlet in 16bpc mode. LW can only read and write 8bpc Quicktimes. If you want 16bpc support,

But LW can export 16bpc PSDs, as per your tutorial, QT's would just be icing on the cake imho.

Beamtracer
03-25-2004, 11:26 PM
There are advantages to rendering to image sequences, in that you've got something if the render fails, and it works well with Screamernet. But with Lightwave you can render to an image sequence and an 8bpc Quicktime simultaneously.

If LW could render straight to 16bpc Pixlet Quicktime, you would still render to QT and image sequences simultaneously, but the Pixlet Quicktime would become the master, and the image sequence would only be a back-up which could be deleted when the render is successfully finished.

Doesn't this seem like a good idea?

Nobody seems to want Lightwave to work with 16bpc Pixlet enough to add their voice to the feature request list: :(
http://vbulletin.newtek.com/showthread.php?s=&threadid=20186

Originally posted by toby
But LW can export 16bpc PSDs, as per your tutorial, QT's would just be icing on the cake imho. You're saving on time, by not having to translate it later. You're saving on file size. You're gaining image quality.

archiea
03-25-2004, 11:34 PM
I think you also need a 1ghz processor to run it, which my mac 128k doesn't have......

toby
03-26-2004, 12:14 AM
I just think there's more important things to do first - like bug fixes and SDK for Worley :cool:

Ade
03-26-2004, 04:55 AM
I read Pixlet wasnt made for us but for studios where they have rendered off test sequences and wanted to transport it to other parts of the studio compressed with no loss of quality.

Johnny
03-26-2004, 07:19 AM
Originally posted by Ade
I read Pixlet wasnt made for us but for studios where they have rendered off test sequences and wanted to transport it to other parts of the studio compressed with no loss of quality.


I can envision a very immediate benefit for a 'small' operator: taking a bunch of 40MB sequences into FCP as opposed to a bunch of 400MB sequences...that would make editing in FCP about 10x faster, owing to the smaller source files?

when done, you can then save out in any format you like, right?

J