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How to use Wild FX Pro video titles with an alpha channel in Adobe Premiere and Sony Vegas
Many people want to create video titles with transparent backgrounds so they can then import them into their non-linear editing software (NLE) and overlay the titles onto existing video. You can do this using Wild FX Pro. This tutorial contains information on how to do this with two popular NLEs: Adobe Premiere and Sony Vegas.
About the Alpha Channel

One of the most popular methods for creating transparent backgrounds in video is to use an alpha channel.

Images represented on video are composed of three grayscale images called channels – one red, one green, one blue - or RGB images. An alpha channel is a fourth channel in
an RGB image that defines what parts of the image are transparent or semi-transparent.
An alpha channel can be either straight or premultiplied, depending on the program that created the image. Wild FX Pro uses the straight alpha channel. When an image contains a straight alpha channel, the transparency information is stored only in the alpha channel.

Activating the Alpha Channel in Wild FX Pro

When you select the transparent background option in the Video tab you activate the straight alpha channel setting in the graphics mode of your output video. This enables you to use the alpha channel setting if you select an output codec that supports alpha channels. If a codec which does not support alpha channels is used, the alpha will be lost in the final output. By adding an alpha channel, you can bring the video into a video editing software that supports alpha channel, such as Adobe Premiere and Sony Vegas, to make the background transparent.

In order to export video titles from Wild FX Pro with a transparent alpha channel you must do the following:

1. You must check the "Transparent Background" checkbox in the Video tab.
2. You must use a codec that supports the use of alpha channel.
The following formats/codecs support the use of alpha channel transparency through Wild FX Pro:
MOV: Animation, None (uncompressed), PNG, TGA, TIFF, Indeo
AVI: None (uncompressed)
Image Sequences: PNG, TGA, TIFF
3. You must set the color depth option to "Millions of Colors+". Do not forget the "+" because the "+" is for the alpha channel.
(Please note that when using transparency, the background will appear white if you play the video file until you key out the background using the alpha channel option in your NLE.)

In the video tab, select “Options”. This brings up the Movie Settings window.

Selecting the “Settings” button in the Movie Settings window opens the Compression Settings window. Here you select the codec you wish to use and set the color depth.
Note: Certain codecs have an additional “Options” button in the Compression Settings window, which opens the Encoder Configuration window for that particular codec. Here is an example:
Other factors to consider when using Alpha Channel

Adding an extra frame
Many of the effects in Wild FX Pro have elements in them which can appear on the first frame of the output and throw off the alpha channel setting. Consequently, Wild FX Pro automatically adds a single frame to the beginning of the output if you have selected the transparent background option. If you do not want to have this extra frame added, you can select the "Remove extra frame from transparent video output" in the Options window.

Solid background
You will need to use a solid image background color (preferably black or white) without any gradient or image fill to use the alpha channel setting.
Working with NLEs
Once you have brought the video title into your non-linear editing software there is typically some method used to activate the transparency, so the program will know to make the background of the selected video transparent. Below are the methods used for Adobe Premiere 5 and Premiere Pro as well as Sony Vegas 5.
Working with Adobe Premiere
Adobe Premiere 5 

First you place your main video on layer 1:

You will see the video in your preview window:
Next you place your transparent title on layer 2 or higher (to be superimposed a video track must be on any track other than Video 1):
You select the title video by clicking on it and then you open the transparency options:
Set the key type to “Alpha Channel”.

You can then set the active area of your project by dragging the active area bar over the area you wish to activate:

If you want to preview your video output you can choose to render the selection
Then you can check your output:
Adobe Premiere Pro

It is even easier to apply the alpha channel settings in Adobe Premiere Pro. This is because by default Adobe Premiere Pro preserves and displays the clip with transparency in all sequences where you use the file as a clip. All you have to do is ensure that the video title with alpha channel is on a higher video track.
Adobe Premiere Pro composites clips from the lowest track up, and the final video frame is a composite of clips on all visible tracks.

Other Key Options in Premiere
Premiere has numerous other options for keying out the background including Chroma key, RGB difference, Luminance, Black Alpha Matte, etc. However, we advise using the Alpha Channel method described above with Wild FX Pro’s video output, because you will get the best quality result.
Sony Vegas 5
Import your video files into Sony Vegas. They will appear in the media pool. Media pool
Put your video titles on the timeline above whatever clip you wish it to appear over.
Right click on the video and select properties
In the "Media" tab select your option for the "Alpha Channel". Change the setting from "None" to one of the other options provided.
To view the composite output, render your selection.
Then you can view your composite output.
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