Confusion understanding Keyframe buttons in mask?

BenB wrote:

A keyframe is a specified frame of your video, in which you "key" or lock-in specific parameters that you choose. Then those parameters are locked into those values on that frame.

Change them on a second frame to cause movement or changes to your chosen parameter over time.

You must have two keyframes in order for them to actually do anything. One keyframe will cause the entire clip to adjust to what it's set for. And for more complex animations, you can have several parameters change over time with many, many keyframes. As long as you don't make so many you get confused or blow up your Mac real good. I hear keyframes are generally happy folks, but get nasty when angered...

Michel Boissonneault wrote: So I don’t know in the first place,if in one video project file, can you add two keyframes and if you can, when and why is the second key Frame added? Can you give me an example that will be better to understand as in? Why? Under what circumstances could the second frame be added? You said that the buttons allow you to go directly to one or the other to modify the adjustment does avoiding adding a key Frame between two. I really didn’t understand the meaning of this. We use a keyframe to apply parameter adjustments to a specific timecode. Example: position your mask around a face that changes place in the frame of the image over the duration of the clip in timeline. The person moves. You use the "+" button to do so. When you move the playhead later (or earlier) and move and adjust the mask to better track the face that has moved in the image, you automatically add a second keyframe. From this moment, the previous and next buttons are available. They allow direct access to the point where the adjustments were made to modify them as necessary. If they are modified elsewhere than on one of the keyframe points, a new keyframe is inserted, without using the "+" button. Look at the FCP help page as suggested by BenB. Michel

Ok, so let me understand if I have understood you guys clearly. There are certain things about key Frame, which is let’s see if you have applied a mask to the video file project I am working on. Let’s say you I have applied that mask do a thing or on the subject phase, and when The frame moves forward to the next if the mask is going a little lot of place on the wire. I had a key Frame, so the first frame is added. Then with the move right key on the keyboard. I go to the next Frame, adjust the mask and that creates the second key, Frame and the same way if I have adjusted the mask for 10 frames. I have 10 key frames on my project? Is that correct? and only if there is one or more key frame the previous and the next KeyFrame button appears in the video inspector? is that also correct?

Michel Boissonneault wrote:

Hi (bonjour),

When there are two keyframes added with different parametres, the buttons allow you to go directly to one or the other to modify the adjustments, thus avoiding adding a third keyframe between the two. In your example, there is only one keyframe and the playhead is later, so the only button available is previous.

Michel B.

Hi Michel,

i’m sorry, but your answer has left me more confused. So I don’t know in the first place,if in one video project file, can you add two keyframes and if you can, when and why is the second key Frame added? Can you give me an example that will be better to understand as in? Why? Under what circumstances could the second frame be added? You said that the buttons allow you to go directly to one or the other to modify the adjustment does avoiding adding a key Frame between two. I really didn’t understand the meaning of this.

BenB wrote:

Place a keyframe on the first frame of the movement, then a keyframe on the last frame of the movement. Then go back and tweak every few frames if needed. Or use a tracker.

Ok, let me try to understand what you are saying. In a project like in a video file, I can add a keyframe by clicking the + sign in the video inspector. For example, if I’ve applied a mask and it’s missing a section, I add the first keyframe and then adjust the mask. Then I go frame by frame using the right key on my keyboard, and the next keyframe is automatically applied. And this ends where I stop adjusting the mask? There’s no + sign available again to add another keyframe in the video inspector. So, what does it mean when you say "Place a keyframe on the first frame of the movement, then a keyframe on the last frame of the movement"? There’s no option to add keyframe in the last frame?

Can you please explain ?

BenB wrote:

Sometimes you have to mouse over the Keyframe Diamond to make it visible on a frame where it is not set. You do not need one on every frame.

https://youtu.be/ymJHFscAur0

Why Mask exactly are you trying to adjust. Sounds like you need to use the tracker.

Ok So when to use keyframe in a Mask and when to use Keyframe in Transform as it is shown in the video you linked? I am using a Gaussian Blur to blur the face of the subject and then using a mask to hide only the face and yes after applying the mask for the first time I did run the tracker and after using the tracker since it did not cover some parts, I am then using keyframe (But directly in the mask) and not in Transform, so how are these two different ? Appling a Keyframe directly in the mask versus applying it in Transform section ?

Sometimes you have to mouse over the Keyframe Diamond to make it visible on a frame where it is not set. You do not need one on every frame.

Nope ! still lost on this. not getting it.