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virtualcomposer
09-12-2008, 03:24 AM
I normally export my animation as a mov file but I'm hearing that when LW is finally out of beta it will be in 64 bit and QT pro will not support it. I'm hearing allot about Image sequence. Do I just export animation as a jpeg and still get the same high quality I'm used to or what?

Lightwolf
09-12-2008, 03:43 AM
Not if you use JPEGs (lossy compression) ;) Render to PNGs instead (which use a lossless compression).

One advantage is that this allows you to tweak the video encoding settings with re-rendering from LW.

Cheers,
Mike

virtualcomposer
09-12-2008, 05:54 AM
Will Final Cut recognize PNG?

K-Dawg
09-12-2008, 06:29 AM
I don't know much about Final Cut, but it should. Every decent editing tool should be able to Import Image sequences in different file formats.

Greetz

virtualcomposer
09-12-2008, 06:30 AM
I hope so because I'm tired of rendering something for 12 hours only to find out it's useless because of file format issues and image degradation. Thanks, I'll test it today.

3DGFXStudios
09-12-2008, 08:30 AM
That's why everyone is using image sequences.

massmusic
09-13-2008, 10:49 AM
PP & FCP recognize TGA which is what I always use

virtualcomposer
09-13-2008, 01:11 PM
Does using image sequence save render time as well?

Surrealist.
09-13-2008, 01:25 PM
No, I don't think so.

Think of image sequences this way:

Would you spend the time shooting a film with all the production value in it and so on and then go to the lab and tell them to trash the negative? "Na I don't need it, we have the print and/or the telecine we're good to edit. Thanks bye."

That is pretty much the same logic as spending all the time to render and then letting the still frames go to waste by only saving an animation. The still frames should be saved and backed up on a DVD or some other format and stored.

This is your negative. Of course you have the scene files but render time is one of the most costly portions of a small production.

Then have at it with the video files. You can try as many things as you want and you still have the stills to go back to.

Lightwolf
09-13-2008, 01:56 PM
Does using image sequence save render time as well?
Actually, depending on the codec used they can, but it is probably marginal compared to the time need to compute the image in the first place.
Of course, once you render on a farm you can't render directly to a video file anyhow.

Cheers
Mike

avkills
09-13-2008, 05:19 PM
I use Final Cut; but everything from LW goes through After Effects to get to the video codec of the day. I would probably strain the images through Motion first instead of directly in FCP if you don't have After Effects. I use the Targa format since it can have an embedded Alpha channel; although I am eventually going to switch over to EXR once I have time to noodle some kinks I have with it (mostly since I have little to no experience dealing with them).

-mark

Mr Rid
09-13-2008, 11:55 PM
'LW_TGA24' saves with a lossless compression. The 'Targa Format' saver will save uncompressed TGAs. The only time I've needed uncompressed is for extreme detail in subtle gradients. For comping, 'LW_TGA32' will contain an alpha.

EXRs contain far more color range/information for detailed post processing.

For an extreme example, may take an image with clipped highlights,
63267

normally, a gain down will only turn the clipped whites to grey,
63268

but gain down an EXR and all the detail is still present under the blown out area (same for black shadows),
63269

Lightwolf
09-14-2008, 05:07 AM
'LW_TGA24' saves with a lossless compression. The 'Targa Format' saver will save uncompressed TGAs. The only time I've needed uncompressed is for extreme detail in subtle gradients.
If the compression is lossless (such as the one used for TGAs) you might as well use it, it doesn't loose any detail at all.
The only mainstream image formats with lossy compression are JPEG, JPEG2000 (in most cases, it does have a lossless mode as well) and some compression modes for OpenEXR.
PNG and TGA only support lossless compression.

Cheers,
Mike

Philbert
09-14-2008, 01:27 PM
I usually use TGA for my image sequences. In one sense it can save render time. Suppose you do your render and then notice a mistake or something that only occurs during a couple of frames. With rendering as Quicktime you'd have to fix the mistake and render the whole scene again. With an image sequence you can just render those few frames.

virtualcomposer
09-14-2008, 10:32 PM
So in my animation output, what should I save it as? I'm confused. How to I save as an image sequence if I have 500 frames to save? What are the steps? Is it in Render Globals?

Mr Rid
09-15-2008, 12:40 AM
So in my animation output, what should I save it as? I'm confused. How to I save as an image sequence if I have 500 frames to save? What are the steps? Is it in Render Globals?

Just enable 'Save RGB' (instead of Save Animation), select Type 'LW_TGA24', and pick a file path to save your frames to. To save an embedded alpha channel for compositing, select 'LW_TGA32'.

Philbert
09-15-2008, 12:45 AM
Right, leave the Animation output blank. If you have Quicktime Pro that makes short work of merging the image sequence into a video. Some programs like After Effects actually work faster if you just leave it as a sequence.

zardoz
09-15-2008, 02:35 AM
guys even virtualdub will do this. I thought that these days no one was still exporting to some animation format...if you are rendering an animation and it will take 2 days to render are you rendering to a quicktime?? Imagine if you have a crash? or someone cuts the power? or you need to check if the renders are ok? Do you have to wait until the animation is rendered? what if you don't have hard disk space?
ALWAYS render to images.
I have even asked here in the requests to be able to export frames in different formats (like tga and hdr at the same time).
Then you can use virtualdub (it's free!) to import the frames and export it to any video format you want.

hisham
09-15-2008, 03:58 AM
Hi

Well, select your OUTPUT tab in Render Global, select save Animation and choose QuickTime (.mov). Then click on Options, which will open the QT conversion window. In this window you can use your compression type. Here you can choose your compression type: Animation ... and a long list. Pick your choice. By the way, whatever you choose here Final Cut will work with it. You can also choose your Quality.

Good Luck.

Hisham

Philbert
09-15-2008, 09:15 AM
Hi

Well, select your OUTPUT tab in Render Global, select save Animation and choose QuickTime (.mov). Then click on Options, which will open the QT conversion window. In this window you can use your compression type. Here you can choose your compression type: Animation ... and a long list. Pick your choice. By the way, whatever you choose here Final Cut will work with it. You can also choose your Quality.


We're explaining how and why NOT to render as animation.

cagey5
09-15-2008, 09:28 AM
guys even virtualdub will do this. I thought that these days no one was still exporting to some animation format...if you are rendering an animation and it will take 2 days to render are you rendering to a quicktime?? Imagine if you have a crash? or someone cuts the power? or you need to check if the renders are ok? Do you have to wait until the animation is rendered? what if you don't have hard disk space?
ALWAYS render to images.
I have even asked here in the requests to be able to export frames in different formats (like tga and hdr at the same time).
Then you can use virtualdub (it's free!) to import the frames and export it to any video format you want.

Guys, even Lightwave will recompile your images to an animation.

http://www.lightwiki.com/Using_LightWave_to_compile_animations

zardoz
09-15-2008, 10:32 AM
lol cagey5, Yeah I totally forgot that...I'm so used to export the frames to some other guy that I rarelly compile them myself!
Excellent point and tip!

medicalart
01-12-2010, 11:51 AM
Render globals, output pane, click the "save RGB" button, and then the RGB files button so you can name a destination folder. Lastly, you'll have to use the pull-down menu in the same panel to select TGA-24 or whatever format you want. Render scene normally. The frames will be saved as separate files, named according to what you typed, and then LW will add consecutive numbers after the name. When you open the frames in another program to assemble them, just select the file 0001, all the rest will fall into place.

KurtF
01-12-2010, 01:57 PM
Lots of pluses for image sequences. If your render crashes, you can begin again after the last complete frame, no need to redo the entire animation file. Single frames can be opened in photoshop for a quick retouch (punch throughs in cloth sims comes to mind).

The only downside is file size, as huge images rendered as lots of frames takes up space, but it's easy to archive and then send those frames to Quicktime Pro or other soft for conversion to a video file.

VirtualFM
01-14-2010, 02:50 AM
And above all those good points on why NOT to render as animation:

You cannot use a renderfarm when saving an animation!

Let's say your animation is a 500 frames 3 Gigapoly scene that has a complex shader tree and takes 10 minutes per frame! That's 83 hours in a row!

Everybody already said that the computer might crash, the power could fail, the cat could walk over the ESC key (it happened before!), but lets think of another situation.

You are in no hurry, and those 83 hours mean nothing to you... The machine is rendering for 6 hours already (it has done 36 frames... only 464 to go!!!) when suddenly... You client calls and would like to see a preview TOMORROW!

a) You are saving to an animation... and you're screwed. There is no way the animation will finish by tomorrow and if you stop the animation and start saving in frames (image sequence) now, you will already loose 6 hours of rendering (or may be not, as you could probably recover most of it by converting the animation to frames, but let's not complicate this!)

b) you are saving to a sequence of frames. You take note of the frame number (37) and stop the rendering. You fire up a renderfarm manager (every 3D artist should use one, even if only using one computer. There are some that are free for up to 2 machines). You pick up that other office computer that is doing nothing in the corner and add it to the renderfarm. You add that 3 year old laptop that will render the same frames in twice the time, but will help, you borrow a computer from a friend of yours. Now you have 4 machines, probably some with dual or quad core. (this is important as it's usually faster to fire up several render nodes, one for each core, than to let it multithread by itself). So sudenly, you augmented your render capacity by at least 300% This means that instead of 83 hours it will take only 27. Since you already spent 6, it's just 21 to go! You wil make it, and tomorrow you will be able to show the animation to your client.

And if you don't get enough machines, you could send the scene to the renderfarm and tell it to render in steps of 2. So you could at least show a preview of the animation, running every 2 frames.

probiner
01-14-2010, 04:05 AM
From what i experienced image sequence might take a bit more, but i do small timeline renders, so i don't know how does that goes for 500 frames or more. Anyway the difference i noticed was very small, but probably cause i use PNG and the PNG's compression and file generation of each frame might take a tiny bit more time than the compression of one video file.

One question i have for you guys though on this subject. (It might make more confusion but hopefully a good answear will prevent that): Been thinking of saving the sequences in HDR files to play with the Gamma in post. 1-HDR make sense only for Stills? 2-Other files that will do better than HDR for post, both in control and file size?.

Cheers

zardoz
01-14-2010, 08:37 AM
I tend to use exr rgba half. this one is enough for me and it saves the alpha. And for stills too.

toby
01-14-2010, 09:00 PM
I tend to use exr rgba half. this one is enough for me and it saves the alpha. And for stills too.
Definitely. If you want max quality it's the best way to go.
EXR is like HDR but with the alpha and better compression. The 'half' type is also 16bit instead of the HDR's 32, which also reduces the file size. No real reason to use .HDR format anymore.

probiner
01-14-2010, 11:21 PM
Thanks for the answear guys.

As for file size, all the HDR's i rendered so far were smaller than the EXRs with no Alpha, even the 'half' ones, but probably because my render have very few information, i don't know.

The Alpha will also have that premultiplied alpha issue, showing a sublte halo of the backdrop color, like any other format right?

Cheers

toby
01-14-2010, 11:56 PM
Thanks for the answear guys.

As for file size, all the HDR's i rendered so far were smaller than the EXRs with no Alpha, even the 'half' ones, but probably because my render have very few information, i don't know.
Hey I just got the same thing, maybe compression was added to .hdr - or I got it backwards -


The Alpha will also have that premultiplied alpha issue, showing a sublte halo of the backdrop color, like any other format right?

Actually there is no alpha type or process that will not have that, it's why elements are rendered over black.

probiner
01-15-2010, 12:06 AM
Hey I just got the same thing, maybe compression was added to .hdr - or I got it backwards.

Actually there is no alpha type or process that will not have that, it's why elements are rendered over black.

Understood, background will always show up a bit. So it's always needed to make that correction in post when composing... erf that looks like too much work for soemthign that should be easier.
But still... there could be some sort of alpha border for images that don't render the background, so when the alpha masks it, it would be dealing only with object full color, and not a mix of the object and the background... no?


As for the file size... will you render HDR's side alpha files now? :hey:
Actually that has one vantage, Alpha doesn't get punched into the image like it happens with EXR or PNG in poor handler Photoshop.

Cheers

Lightwolf
01-15-2010, 12:14 AM
But still... there could be some sort of alpha border for images that don't render the background, so when the alpha masks it, it would be dealing only with object full color, and not a mix of the object and the background... no?
That's what unpremultiply alpha (which results in a straight alpha in LW) does.
However, since it is essentially a post process, it only works as expected if the background is black.
Due to the nature of 3D rendering, any alpha produced in that process is pre-multiplied anyhow.

Compositing packages tend to prefer premultiplied alphas anyhow (video editors seem to prefer straight alphas).

Heck, technically it's not even the alpha that is premultiplied or not, it's the RGB. The alpha stays identical.

Cheers,
Mike

probiner
01-15-2010, 12:31 AM
Thanks for the explanation Lightwolf.
So render with Unpremultiply is not really necessary basicly if your rendered background is already 0,0,0 black... gotcha.

"Highjacker out" ;) (couldn't resist to wink to you)

toby
01-15-2010, 12:58 AM
Understood, background will always show up a bit. So it's always needed to make that correction in post when composing... erf that looks like too much work for soemthign that should be easier.
But still... there could be some sort of alpha border for images that don't render the background, so when the alpha masks it, it would be dealing only with object full color, and not a mix of the object and the background... no?
Well you can just set the unpremult flag like Lightwolf mentioned, or if you'd rather crack open the render code and write something, rather than just stick a black image in the bg, go ahead! But the results will either look wrong before pre-multing or after, you can't have it both ways. Anti-aliasing works by blending an objects' color with the color that's behind it, so some of the bg color will always be there.


As for the file size... will you render HDR's side alpha files now? :hey:

Nah, I always use the alpha.


Actually that has one vantage, Alpha doesn't get punched into the image like it happens with EXR or PNG in poor handler Photoshop.
Actually Pshop has an unpremult option when you open exr's, so it's ok

probiner
01-15-2010, 01:18 AM
Actually Pshop has an unpremult option when you open exr's, so it's ok
Noticed. EXR all the way http://i153.photobucket.com/albums/s202/animatics/Foruns/dance2.gif

toby
01-15-2010, 08:08 PM
EXR supports tons of stuff, like multiple rgb channels in one file, mipmaping options for exr textures, both l&r stereoscopic views in each file, etc. LW can't do any of this stuff native, but Lightwolf has a plugin that saves multiple channels - http://www.db-w.com/content/view/81/104/
Only one on the market I think.