Help with Alpha & After Effects

[Bassman]

Hello,

I know this is a little off topic, but I was wondering if I could get some help with keying.

I have asome green screen footage in Edius 4.54 that I need to deliver as an alpha channel only for web work.

I made a key in Edius and exported the original footage as well as the key in greyscale as lossless files.

I have put the files in After effects but do not know how to make the rest work.

Since Edius does not export alpha, could somebody tell me how to make these two files produce my subject as an alpha layer?

Thanks!

- Hoping for some off-topic lee-way!

[EdiReady]

I'm looking for the exact same help.....anyone please!!

[Claire]

Hello,

I know this is a little off topic, but I was wondering if I could get some help with keying.

I have asome green screen footage in Edius 4.54 that I need to deliver as an alpha channel only for web work.

I made a key in Edius and exported the original footage as well as the key in greyscale as lossless files.

I have put the files in After effects but do not know how to make the rest work.

Since Edius does not export alpha, could somebody tell me how to make these two files produce my subject as an alpha layer?

Thanks!

- Hoping for some off-topic lee-way!

Place the original footage on a layer in AE and the key on a higher layer, toggle "Switches/modes" to show "modes" and set TrkMat (track matte) to "Luma matte".

It's been a while since I used this so if it fails just juggle the order they are on the tracks, can't honestly remember the order right now but when you have it correct and set track matte the key will work to make black (or is it white?) opaque revealing what is on a lower layer.

To save with alpha be sure to use Canopus HQ, uncompressed AVI or QT animation 32 bit.

[Bassman]

Thank you very much Claire.

The matte is working, but now I have another issue.

When I open the file I exported from Edius in Windows Media Player (the finished file with the key) it looks great.

When I put the files in After Effects, apply the matte and export, the result is a file that is not quite as sharp as the original.

I have "best quality" checked on the footage.

Since Windows Media Player will not play lossless files, I am exporting with Canopus DV.

Will exporting lossless keep the orginal sharpness?

Since this file will not go back into Edius, it will be delivered to the client from After Effects, Are there any best settings for the output module to retain the image integrity?

Thanks for any help!

[Bassman]

I just output a lossless file from AE and put in Edius next to the orginal on the timeline.

The AE file looks soft and their is a color shift.

Here was my workflow:

Make the key in Edius
Export Canopus Lossless (video with key & greyscale Key)
Import into AE with DV project setting 29.97 framerate.
Select "best quality" for the footage
Output lossless from AE

I have read a bit a bout interpreting the footage on the way in to AE.

Does anybody know about this?

Just wondering where my image quality is going.

Thanks

[GrassValley_BH]

Is AE rendering RGB or YCbCr?

[Claire]

Bassman, there are some decisions to make when passing footage back and forth between AE and Edius that are important if you are to cope with the conversion between Edius' YUV where luma level black is 16 and white 235.

AE works in RGB where black = 0 and white = 255 so you need to handle this conversion when passing back to Edius.

When exporting from AE using the HQ codec two options are present that are not there when using this codec to export from Edius.

(1) RGB has ITU-R BT.601 range

(2) Convert RGB range [0,255] as IRE [0,100]

Although the options are headed "Color space conversion" my tests so far indicate that only luma levels are affected by them, not colors.

This proved a particular issue for me when I first took a piece of footage from my V1E HDV camera captured with Edius as HQ avi into AE to stabilise it's motion and like you found the colors were wrong when exported back to Edius.

The IRE luma levels were fine provided I used option (1) above to preserve the original luma range.

The best solution I found was to use AE7 rather than AE6.6 which in project settings has the option to chose the working space, with "HDTV (Rec, 709)" option selected a render now produced an identical clip to the original when in Edius.

Reds, orange and pink seem to be the colors most different when the color space is not preserved, however colours should not be an issue if you are working in SD DV which is REC601.

So for Edius footage with HDV there are two things to remember, first the project settings need to be 709 color space and second, when exporting with HQ codec choose "RGB has ITU-R BT.601 range". For SD DV I suppose there is only the luma levels to worry about.

A further point, on reflection I would stay away from importing any Quicktime files as Edius messes up their colours.

[Claire]

Here was my workflow:

Make the key in Edius
Export Canopus Lossless (video with key & greyscale Key)
Import into AE with DV project setting 29.97 framerate.
Select "best quality" for the footage
Output lossless from AE

How are you outputting from AE ? You should use the render queue window where you can make sure your output settings match the footage details as shown in the project window, eg: quality best, fields render (upper or lower), frame blending and motion blurring off.

Does it look good in the AE comp window? If so it's the export settings, otherwise it's the comp settings not matching the footage.

[Bassman]

Thanks for your replies.

AE only has the option of RGB or RBG + Alpha in one of the output dialogues.

This is an SD project that will be given to a web designer, so I don't know how exotic I can get with the file output type. (Canopus HQ).

I just dowloaded the AE CS3 demo today and will try some stuff with that tomorrow. Right now I am using AE 6 non-Pro.

The video looks a bit off in the AE preview window, but to be honest, I don't see a lot of stuff to change in the project settings.

Should I expect the video to look exactly the same as it does in Edius? Or are my expectations too high?

Thanks again.

[Claire]

You won't see all the output options in AE unless you use the render queue (window menu). Then you should see all the codecs you have available on your computer including Canopus HQ codec but I take your point about needing to use a non propriatory codec to send the file to a third party and really the only thing to worry about is the luma levels depending whether your client is going to use them in something that works in RGB or YUV. That is if they are not able to adjust the levels to suit their equipment.

To ensure your comp project is correct there is a shortcut, import the clip from Edius and drag it from the project window in AE to the "make comp" icon on the bottom of this window, this will make a comp the exact dimensions and aspect ratio and frame rate, it should also detect the field order if any.

What way is the image in AE comp window off? Color, black levels? Normally it will look bright and pale in AE since black level 16 in your Edius clip will look grey in AE which regards zero as black. It this is the case you can correct the levels with AE's Levels histogram, set the input black to 16 and the input black to 235. Now your clip is ok to send to such as Vegas which I believe works in RGB.

[Bluetongue]

I have asome green screen footage in Edius 4.54 that I need to deliver as an alpha channel only for web work.

I made a key in Edius and exported the original footage as well as the key in greyscale as lossless files.

I have put the files in After effects but do not know how to make the rest work.

Since Edius does not export alpha, could somebody tell me how to make these two files produce my subject as an alpha layer?

Thanks!

- Hoping for some off-topic lee-way!

EDIUS does export in Transparent Alpha but the process is hidden
Go to Help and type Alpha in the Index and select "Alpha Channel"
But here is a description
Save both the clip and the Greyscale black and white matt in CanopusHQ
Both will appear in the bin
Select Both
Right click and select convert
select Alpha Matt
In the Fill Key select the non Black and white file (Fill)
Select either Luminance Matt or Luminance Matt (Invert)
a depiction of the output will be shown in the window
Change or type in the file name and select the format to save in and you have a clip with transparent Alpha.
ALL from Edius
Regards Barry

[Bassman]

AHHHH!

Thank you so much Barry.

This is great. The clips have alpha and they look as they should.

No need to upgrade my After Effects just for this project.

Edius never ceases to surprise me with its capabilities.

[Bassman]

Thank you for your help Claire.

I will still check out AE CS3 and learn about what you said.