- \item[Key color:] Select the key color (green, blue, etc) using the color wheel or the color picker. Remember, only the Hue matters, not Saturation or Value. To use the color picker, click on the \textit{color picker} icon in the Compositor window, then click on the color you want in the Compositor window. Finally in the Chromakey (HSV) parameters window, click on \textit{Use Color Picker}.
- \item[Hue Tolerance:] Because there are slight variations in lighting, the background will not be in a uniform key color hue. Increase or decrease the Hue tolerance to mask out the background. If there are dark spots that are keyed out that shouldn’t be, it can be corrected later.
- \item[Brightness:] ncrease \textit{Min Brightness} so that only the background is masked out, and not parts of the foreground. You can also reduce \textit{Max Brightness} if some clear areas are keyed out (useful for very dark backgrounds).
- \item[Saturation:] Increase \textit{Min Saturation} so that only the background is masked out, and not parts of the foreground. \textit{Saturation Offset} can be used to change this, but for now leave it set to $0$.
+ \item[Color...] Select the key color (green, blue, etc) using the color wheel or the color picker. Remember, only the Hue matters, not Saturation or Value. To use the color picker, click on the \textit{color picker} icon in the Compositor window, then click on the color you want in the Compositor window. Finally in the Chromakey (HSV) parameters window, click on \textit{Use Color Picker}. Remember to disable ChromaKey (HSV) plugin when using the Color Picker on the Compositor window.
+ \item[Show Mask] The plugin does not create a true matte in the alpha channel, but creates a mask. Activating this option will show the foreground as a white (opaque) shape while the background in black (transparency). You will be able to control the extent of the mask, any jagged edges, small black areas within the mask or small white areas within the foreground, which are to be removed, etc.
+\end{description}
+
+\qquad \textit{Key parameters section}
+
+In this section we expand the mask to a range of colors close to color key and refine the selection by also taking advantage of brightness and saturation.
+
+\begin{description}
+ \item[Hue Tolerance:] Because there are slight variations in lighting in real cases, the background will not be in a uniform key color hue. Increase or decrease the Hue tolerance to mask out the background. If there are dark spots that are keyed out that shouldn’t be, it can be corrected later (With the \texttt{Mask} tool, this operation is called the \textit{Garbage Matte}).
+ \item[Brightness:] It allows the color range (Mask) to be better defined by exploiting the differences in brightness between background and foreground. This could be referred to as a Luma Key within the Chroma Key. Increase \textit{Min Brightness} so that only the background is masked out, and not parts of the foreground. You can also reduce \textit{Max Brightness} if some clear areas are keyed out (useful for very dark backgrounds).
+ \item[Saturation:] It allows the color range (Mask) to be better defined by exploiting the differences in saturation between background and foreground. Since the best results are obtained by keying pure colors, it may come in handy to eliminate the less saturated colors (proper to the foreground) while leaving the more saturated colors (proper to the background, i.e. Green/Blue Screen) to the keying action. Increase \textit{Min Saturation} so that only the background is masked out, and not parts of the foreground. \textit{Saturation Offset} can be used to change this, because it acts similarly to Min Brightness. It could be said that Min Saturation concerns only the key color, while Saturation Offset concerns the range of Hue tolerance. But it is best to start by leaving it at $0$.