Graph deduction strategy in FW (6)-send to FW beginners (black and white backgrounds and monochrome backgrounds with non-black hair)

Haha, the title is clear enough, so I will not repeat it again.
In the figure deduction tutorial (4), we recommend a filter to convert to Alpha. In fact, for a white background (if it is not white, the color level filter is used to create a white background). Using the "convert to Alpha" filter is really a good way to remove the back, even if the hair is not black. In this example, we will discuss in depth the key points.
First, let's look at the material diagram:

The background color is white, but the hair color of two mm is not the same. One is black and the other is yellow. How can this problem be solved? What will happen if you follow the methods provided in tutorial (4 ?! Let's take a look at the specific steps.

1. Good habits: first copy a new layer to hide and lock the layer where the source image is located.

2. Select a cable appliance. The attribute panel is not changed. The "edge" uses the default "Solid Edge" effect.

3. Place the character subject in the top-level image, and then convert the bitmap object in the middle layer to Alpha. The effect in the editing area is displayed.

4. Black hair is okay, and the effect of yellow hair is too bad. This is not what we want. Fortunately, there is a work und. However, I would like to declare that this method is only applicable to users who do not have very high requirements on the final effect of graph deduction. I hope you can understand this.

Okay, let's try again!

1. Operations above
2. Select the plug-in tool, set it on the property panel, set "edge" to "Feather", and set the value to about 30 (note: the size of the value is closely related to the nature of the image ).

3. Repeat the above operation to see the effect.

4. It seems that it basically meets our requirements. Add a background image to see the effect!

5. The problem has occurred. The problem of "bottom leakage" occurs in steps 1, 2, and 3. This is the result we did not pay attention to during the above 2nd operations.
6. Undo the operation and re-return to Step 1 to select the selected constituency. Extend the range of the constituency to the subject of the character as much as possible.

7. I will not repeat the subsequent operations. Let's take a look at the final results!

In fact, this example is a supplement to the previous tutorial (4! Hope you don't bother me !!
Homework:
Clip:

Please pay attention to the release of the graph deduction series (7 !!