- 1 Introduction
- 2 Timeline Preview
- 3 Effects in kdenlive
- 4 Common parameters in all effects
- 5 Types of effects
- 6 Dynamic Effects (Animatable)
- 7 How to insert effects in Kdenlive?
- 8 Add effects to clips contained in the “Project Folder”
- 9 Practice with dynamic effects
- 10 Tips on Kdenlive
As a reminder and briefly, since I insisted a lot on this point in the previous entry, a video montage is made up of at least two phases, the basic montage, which is the one we saw in the previous post. And advanced assembly.
Advanced video montage is understood as the process that includes the application of effects and transitions on the basic montage.
The goal of this post is to learn how effects are applied and work in Kdenlive.
Here we will only see some of the effects it contains, since they are all applied in the same way, although each effect has its particular and exclusive parameters, a color correction effect is not the same as a blur effect, but the way to apply them the project is the same in all of them. Seeing them all would be an extensive task. In this post we will see some, in following posts, we will see others.
I also want to indicate that in this post we will only see the insertion of effects and we will not see the transitions for the moment, we will see them in depth in a tutorial dedicated to them.
Tool to preview advanced editing in real time
When we apply effects and transitions to a video project, the computer to display them has to do a series of calculations in real time that cause playback to slow down and even stop intermittently, making it difficult for us to see how the video is doing at the speed of defined frames (in real time).
Kdenlive, like professional editors, has a tool that allows you to solve this problem effectively. Basically what this tool does is calculate the fragments that we indicate and write the result to the disk in order to load it into memory and be able to see said fragment in real time. Indicate that this calculation is volatile at the minimum change we make, it is obvious that if we change a parameter of the effect, the affected fragment must be recalculated.
I must give a warning !!!, caches are very useful, but they can also create a lot of headaches. If this is not refreshed or deleted automatically (which happens quite frequently), we may be seeing a wrong result of our editing, so if we observe “strange things”, for example, we have just changed a parameter or a clip and we continue to see the video the same as before we changed it, or we see video fragments that do not correspond to the clip, etc, It is IMPORTANT, before you start looking at what is happening and wasting your time, as a first step, DELETE THE CACHE to be sure that it was not a traffic jam.
I also want to mention that when playing the preview it is preferable that there are no selected clips within the playback area, since sometimes this selection produces a flash of black that may seem like an error.
In Kdenlive this tool is called “Timeline Preview” and it is found precisely in the Timeline menu:although we can access it faster from the timeline toolbar:
Important: If our computer or our graphics card is not very powerful, it is convenient to choose the “Preview” mode from the menu that is located in the upper left corner of the timeline. This is also very useful for making previews much faster.
WARNING: When we are in “Preview” mode it is true that everything will go more fluid, but there may also be display errors when we apply effects and transitions, even with transparencies, so if we observe strange things it is better to do the test in “High Quality ”before wasting time with it. If we select “None” the transparencies do not work.
When exporting the video it is important to have the “High Quality” mode activated. since if not, it will be exported at low quality. A warning notice is output when exporting with “Preview” mode activated.
Let’s see how it works:
- Define the area that we want to preview using the bar that defines the playback area:
- Now just press the button and the selected zone will begin to calculate the preview. This will be indicated by a bar that appears in red just below the playback area and turns green as you calculate; when the area is totally green it means that this fragment can already be viewed in real time.We observe that the button indicates the approximate time that the calculation will take.
This will always be the case the first time or every time we use the option “Remove All Preview Zones”(Delete all zones).
If NOT let’s use the option “Remove All Preview Zones“And we already have a piece calculated in green, in order to add more time to this cache we will have to place the reproduction area in the desired place or simply lengthen the area and use the option”Add Preview Zone”(Add zone)
Now to perform the calculation we simply press and the area marked in red will be calculated to be able to preview in real time. The keyboard combination for this is “Shift + Enter”
The remaining options:
- “Remove Preview Zone”(Delete the preview zone) deletes the zone indicated with the bar that defines the zone and if we wish to recalculate said zone we must use“ Add Preview Zone ”again so that it can be recalculated.
- “Automatic Preview”(Automatic preview) if you have a powerful computer, fine, as soon as you add a zone it will be calculated without pressing the button.
- “Disable timeline Preview”(Disconnect the preview from the timeline) just does what it says and is very useful in case we suspect that the cache has not been refreshed and prevents us from seeing changes made after the calculation. We can use this option to get rid of doubts before deleting the calculated so as not to have to calculate the entire area and only delete the piece that gives us the error.
- “Manage Cached Data”(Manage cache data) tool that allows us to see the space occupied by the cache. It allows us to clean up to free up disk space and it even has a tab with the data of all the projects that have cached data.
Remember that these previews consume resources, that these tools are designed to see the fragments that we are working on in real time. If we define very long time limits, the calculations can take a long time. And most importantly, if we see that suddenly a fragment we are working on does not change despite having manipulated any parameter that should cause a change, think that “the cache may be deceiving us”. Before deleting it, we can deactivate it with the relevant option or even delete this fragment where we are working to recalculate it. The preview is not to see a complete long video, for this we can export fragments and save on resources.
If we observe some inexplicable preview error with this tool, before wasting time looking for the solution, it is best to select the fragment where we observe the error with the playback area and export only this small fragment to see if the error persists in the export. To do this, all you have to do is have the “Zone selected ”.
Effects in kdenlive
The effects are classified in an orderly manner according to their function to facilitate their location. In the following image we see the options of the effects tab.
Square icons indicate video effects and round icons indicate audio effects.
Common parameters in all effects
From left to right:
- disable or enable the effect without losing the parameters.
An effect can be saved with the modifications made. This is located in the “Custom” section of the effects tab.
- Buttons up and down the effect stack. It should be known that varying the order of the effects can totally change the final result.
- Delete effect button.
Types of effects
We have seen that Kdenlive arranges the effects in an orderly manner by different families and each group affects the edition in a certain way, but apart from this classification we have two types of effects:
- Static Effects: They cannot be animated over time. Once inserted and configured, their assigned values will remain the same throughout the clip.
- Dynamic Effects: They can be animated and their values can vary over time. An effect is known to be dynamic because it has a tag in parentheses (animatable) in its name that indicates it. Although many of them do not carry this indication if they have an indicator in the shape of a clock or a line to insert key frames (keyframes). Let’s see this in the images below:
In both cases, despite not indicating it in the name, it is possible to animate its parameters. Despite being dynamic, if its values do not need to be animated, we can use them as static.
Dynamic Effects (Animatable)
How do they work to animate the parameters?
We have two types, the “clock” and the keyframe bar:
Let’s see how the “clock” works
When activating the clock, a box with two keyframes appears, one at the beginning and the other at the end of the clip.The time of the key does not correspond to that of the project, only that of the clip. The clip in the image could be at position 00: 05: 22: 12 in the project so the leading 0 is the beginning of the clip, not the project. We see that the image clip lasts 5 sec. (00: 00: 04: 24)
In the lower left corner of the keyframe are the buttons (from left to right)
Add key: This is added in the center (in terms of time) of the existing ones, and so on they are inserted in relation to the key that we have selected. The place where it is inserted can be moved with the position slider below the aforementioned buttons.
Delete selected key.
Reset the parameters to the initial values of the selected key. Very useful since it only affects the selected one
Synchronize with the project: It is highly recommended to have it activated to see the changes of each key while we vary its values in the project monitor.
Just below these buttons is the control to define position of the selected key
To vary the values that affect the clip, simply select the key and make the desired adjustments to the effect parameters. These are reflected in the columns of the keys box.
It is not a type of keyframe management common in other applications, but by playing for a few minutes with it, we understand its management and we can take advantage of its powerful possibilities. (We will do a little practice with these types of effects so that we understand how they work).
Let’s now see the keyframe bars
The key bar is totally synchronized with the timeline, (it is as if it were a clone of it), in fact if we move the cursor from here we will see that the timeline also moves and we are seeing the result on the monitor.
Just below the key bar on the left we have the buttons to place ourselves in the previous or next key; in the middle of them, the button add key, which becomes delete when selecting a key.
Some effects have interpolation: we know this if we see that the effect has the box in which we see the text “Linear” as is the case in the previous image. This interpolation consists of three options, one freezes the animation, another is linear (maintains the speed) and the third, smooth, starts slow and accelerates and, reaching a midpoint, slows down the movement to go to the end.
This base is common to all effects of both types. Now, next we will see how they are inserted and at the end of this article we will see some fun basic practices that will help us to understand how both types of effects work and the interpolation for those who have it.
How to insert effects in Kdenlive?
First we will see how the fade effects “from black” and “to black” are inserted from the clip itself.
Fades are the only effects that can be inserted from the clip.
These fade effects are very easy to insert with the following technique:Simply move the mouse cursor closer to the upper corner of the clip where we want to apply a fade; if it is input it will be done from the upper left corner of the clip and it will be dragged to the right, if it is output it will be done from the upper right corner and it will be dragged to the left. This works on both audio and video tracks.
Just when we perform the aforementioned action, we will see that the fade effect (s) appear in the properties tab depending on whether we apply a single fade or both. In the following example image we have applied both: “Fade from black” is the input and “fade to black” is the output.To be seen in the properties tab, the clip must be selected. Both are non-animatable effects with a single parameter (the duration) that we can manipulate both from the clip and from the effect. If we drag the fade from the clip until it disappears, the effect will also disappear.
Let’s now see how the other effects are inserted:
As simple as searching the effects tab for the desired effect and:
- If we have selected the clip where we want to insert the effect, just double click on the effect and it will be added to the selected clip.
- If we do NOT have the selected clip, we simply drag the desired effect from the effects tab to the clip where we want to insert it.
If we do this from the menu “Timeline -> Add effect” we must have the clip selected so that the chosen effect is inserted.
We can also insert an effect by right-clicking on the clip and in the contextual menu that opens, look for the option “Add effect”
How to tell if a clip in the timeline has embedded effects:
- In the clip we see a label with the names of the effects. (See the previous image)
- When selecting a clip, if we look at the properties tab, the effects inserted in the selected clip will appear in this.
How to disable all timeline effects:
- In the “Timeline” menu, find the option “Disable timeline effects”
Add effects to clips contained in the “Project Folder”
kdenlive allows us to insert effects directly to the files that we have in the “Project folder”.
To insert the effect (s), simply drag the chosen effect from the effects tab to the clip in the project folder where we want to insert it.
If we select said clip from the project folder in the properties tab we will see the inserted effect.
The visualization of the settings is seen in the clip monitor.
At first glance we know that a clip has effects applied because that clip is assigned a star in its lower left corner.
The settings and animations of the effects work exactly the same as we saw in the timeline.
From the menu of the window “Project folder” we have the option to disable all the effects applied in the aforementioned space.
When inserting a clip with effects to the timeline, said clip will be displayed with the modifications produced by the inserted effect (s) without any indication in the timeline.
I have cited this section because it is part of Kdenlive, but if I may a recommendation, I would not use effects in the project folder. I have a preference to apply them on the timeline.
Practice with dynamic effects
The best way to learn is the combination of the theoretical part to know how it works (it is what we have seen so far in this post), and above all the practice, which is the objective of these simple practices that we will see below.
We will do two simple practices to understand how to work with the two types of dynamic effects and another that will help us see what the interpolation does.
We will work with colored clips so that you understand how it works and you can make use of these resources when mounting your videos.
I will be putting the reminder for repeatedly, since, from time to time, when we work with video editors, the application can be blocked and if we have not saved we can lose changes made. The “tic” of pressing “Ctrl + S” is a very healthy habit, it avoids many troubles.
Remember that it is advisable not to have selected clips within the “Render Preview” area to avoid preview errors.
Practice 1. Working with “clock” effects
- First of all, I create a new project with HD 1080p 25fps resolution with just one video track. And I save as “P_01.kdenlive”
- Now I create a color clip. Simply with the right button of the mouse inside the “Project folder” I choose the option “Add color clip”.
- In the wizard that opens, I choose a color other than the default black. In my case I have chosen red and I have named it “Red” and I leave the duration in 5 seconds. (00: 00: 05: 00)
- I insert the clip directly from the project folder to the video track.
- For this practice we will use the “Vignette effect” effect, which belongs to the family of “Artistic” effects, we will find it and drag it to the “Red” clip.
- Now with the “Red” clip selected in the properties tab we see the effect, we activate the clock and we get the keyframe box with the two default keys, the one at the beginning and the one at the end.We made sure to have the sync button with the timeline activated.
- Now with the final key selected (as we see in the previous image) we add with the + button a new key that will be positioned in the center of the existing ones in terms of time. We leave it in the center since we want it here and we vary the parameters;
- Smoothing we raise it to the maximum that is 10000
- Radio we lower it to the minimum
- X max, 1000
- And to the minimum
- Opacity we do not vary itWe see that the columns of the keyframe box correspond to the parameters of the effect.
These parameters are modified, either by sliding with the mouse or by entering a numerical value in the corresponding box. This last step can be done in the corresponding box in the key box.
- Now if we wish we can preview what we have done so far. We set the playback area to the “Red” clip and calculate the render preview by pressing or “May + Enter”, and once the preview has been calculated, we reproduce it using the combination “Ctrl + Space”
- Now we will select the last key and insert another, it inserts it in the temporal center of the last two, in the second 3 with 18 f. But we do not want it here, the objective is to vary the end of said animation by blurring the sphere that is created with this effect, so by means of the position slider we bring this key to the time value of the 4 sec clip. with 17 f. (00: 00: 04: 17) and using the button we reset the values of this key to the initials of the effect and we modify only the smoothing parameter leaving it with the value 8315 (value visually searched in the project monitor by means of the corresponding slider)
- We select the last key again and insert another. This is inserted between the last two in sec. 4 with 20f. precisely where we want it. We observe that the smoothing value of the previous key (key) is 8315 and the last one is 800 and when this key is inserted, this value adopts the one that corresponds to it in this frame, which is 5094, the remaining ones, as they were the same, do not vary. And so we leave it.
- Now the objective is that in the last frame the screen is completely red, so we position ourselves again in the last key and vary the radius (it can be done precisely by means of the mouse wheel on the corresponding slider). I see that above the value 600 the screen is already full, but to ensure I raise it to 605, the rest are the same.
- Now just to finish I create another 5 sec color clip, in this case blue and I call it “Blue” and I place it just behind the red one, I adjust the playback area so that it covers both clips, I erase the preview area as I explained At the beginning of this article with the option “Remove Preview Zone”, I give it to calculate again “Shift + Enter” and once calculated “Ctrl + Space” to see the result.
Practice 2. Working with keyframe bar effects
In this practice we will insert a 5 sec color clip. and we will do a simulation of what could be a reduced video window and superimposed on a full screen video. Initially it will be static in the lower right corner until 1 second with 12fr. From here, with a 12-frame rotation animation, it will position itself in the center, to stay there until the second 3 with 12fr. Now again, for 12 frames, with one rotation it will go up to the upper right corner. We see that both repositioning animations will last 12 frames each.
We repeat steps 1 to 4 of the previous practice. Changing only the name when we save to “P_02.kdenlive”
- Now we insert the “Transform” effect that is within the family of “Trim and transform” effects and allows us to do what we have proposed in the practice presentation.
- With the clip selected in the properties tab we see the effect. In this type of effects, you do not have to activate anything to show the animation section, only if we want to animate it we will enter the keys that we need.
- The first step will be to reduce the size and place the clip in the starting position, which is the lower right corner. It is recommended to have the cursor at the beginning of the clip.
* Annotation on the scale parameters; We observe in the image that between the width parameter (W for width) and height (H for high) there is an icon in the form of a sheet, if this is activated we will maintain the aspect ratio, so when we manipulate one of the two parameters the other will vary in value; if we deactivate the aspect ratio, the parameters will be independent.
* These are the position and alignment icons, if we put the mouse cursor over it, a text banner will appear indicating its function.
Let’s see how we insert the initial values:
- First from the “Size” box I adjust this to
- The clip is now in the upper left corner and instead of adjusting its position from the effect I will do it from the project monitor itself. Let’s see how this is done.
- We make sure that the visualization tool is activated in the project monitor, if it is, since we have the selected clip, we will see a yellow frame and a cross in the center of the clip
- Now, from the monitor, we drag the clip to the desired position. Note that I have left some margins instead of adjusting it to the edges.Remaining what will be the initial parameters of the effect as follows.
- Now, as we have indicated that this clip will be static in this position for 1sec. with 12fr what we do is place this time in the counter of the effect itself (Remember that when a clip is not at the beginning, the time of the timeline does not correspond to the time of the clip; in this case it does because the clip is at the beginning) and we insert a keyframe with the button .
- We have also indicated that the scroll would last 12 frames, so we add these 12fr. to the previous key resulting in 00: 00: 01: 24.
Now we are in this position.
We can do this either in the effect key bar with the mouse scroll or by dragging to time 00: 00: 01: 24 of the effect counter or from the effect counter itself by entering the value with the keyboard, in this In this case, it would be enough to select the first digit of the frames and enter the value 24.
Once located in this position we introduce a new key.
- We see that the tip of the key is red, this indicates that it is selected, in fact if we click on the head of any frame we select it and place the cursor in its position.Now with the last key entered selected, we adjust the clip in the center by means of the position icons (we press the center on the “x” axis and that of centering on the “Y” axis ) and we already have the clip in the center of the monitor. We also set the rotation value to -360 for a full turn.
* We see that the rotation of this effect pivots on the upper left corner, and this cannot be changed.
* We also observe that its maximum and minimum value comprises a range from -360 to 360, that is, one complete turn in each direction. So as in the next position we have to go with a turn in the same direction as this one, we are forced to make a small trap so that after this turn the rotation value is back to 0 to face the next animation. Let’s see how we do this:
- From this last key we advance one frame, the last key is at 00: 00: 01: 24 of the effect counter, we advance one frame and we are at 00: 00: 02: 00, we can do this precise advance from the own effect counter;
- We insert a new key in this position and set the rotation value to 0 in this key; if we move the cursor from the previous key to this we will see that nothing happens, since -360 and 0 in rotation is the same position. Now we have the keybar as follows:
- Now we go to time 00: 00: 03: 12 of the effect and insert a new key. Here we do nothing else since until this key we have to keep the static clip in the center.
- We are at 00: 00: 03: 24, we have added the 12 frames that we are told that the position change has to last, and we insert a key in this position.
- Now with this last key selected from the project monitor (in the same way that we saw in step “7.2.2”) we drag the clip to the upper left corner, also leaving some small margins. We assign the value of -360º in the rotation and we have finished the animation.
- Now we can preview the result in real time using the “Timeline Preview” tool in the same way as we did in the previous practice.
Practice 3. Using interpolation.
This practice will consist of three superimposed tracks, scaled to 5%, being in the form of rectangles that will go from the left end of the monitor to the right end, each one with a different interpolation.
- We create a new project at 1080p 25fps with 3 video tracks. We save as “P_03.kdenlive”
- We create 3 color clips with a duration of 10 seconds each. I have assigned them the basic colors which are “Red, Green, Blue” abbreviated as RGB. In Spanish “Red, Green, Blue”
- We insert these clips one on each track, all snapped to the start.When we stack layers, the one we see is the one above.
- We insert the “Transform” effect to the layer above (the red one).
- Now we climb to the and using the vertical centering position button, the “Y” axis, we position this small rectangle that our red track has become, in the center; We do not touch the “x” axis since this will be its starting point (which is to the left of the monitor).
- Now we are at the end of the clip: we can do this using the next keyframe button of the effect, this button, if there is no key to its right, what it does is place the cursor at the end of the clip. In this position we create a new keyframe using the + button.
- Now with this key of the end of the clip selected, we press the button to align to the right on the horizontal axis , X axis”. and we see that the rectangle is placed at the other end of the monitor.
- Now we copy the red clip in the timeline, with the right button of the mouse on the clip we choose the option “Copy”
- Now we open this context menu in the green clip and paste with the option “Paste effects”
We repeat the same in the blue clip. After this operation we only see the red clip, since the others are below and we only see the one on the upper track.
- Now we select the red clip and * (important) we select the key from the beginning and assign it a “Discrete” interpolation.
We observe that the head of the key stops being an arrowhead to become a square. * Interpolation works from left to right, so if we want to change it in a section we will always choose the key to the left of that section.
- We leave the green clip with the value “Linear” which is the one we have defined by default and for the blue clip we choose the interpolation mode “Smooth” in the key at the beginning. Its tip will take the shape of a circle.
- Now we can preview the practice at this point to see the result so far.
- Now what we will do is separate the clips so that they are not overlapped in the visualization. To carry out this step, we will vary the value of the “Y” axis until the three rectangles are visible. We select the red clip with the first selected key and modify the value of “Y” until it is above the green one, leaving this value of “Y” in and its display as follows: We see that the red start key does not cover green, but if we go to the end key they will be superimposed again. Here what we do is select the key at the end and enter the same value of “Y” that we have in the key at the beginning. In this example 452.
- We leave the green clip as is, now with the blue we do exactly the same as we have done with the red but with the aim that it remains below the green. Remember to change the value of “Y” in the key at the end to the same value as the key at the beginning. Now we see that the three tracks look like this.
- Now we can recalculate the preview to see the race in real time, where they all arrive at the same moment at the end despite advancing with different speeds. Well the red does not move until the end (where it jumps).
We deduce that the interpolation of the “Discrete” type is to freeze the frame and its values do not vary until the next key is reached (which in this practice is located at the end of the clip) so the red rectangle of this animation does not moves to the last frame of the clip, jumping to the end.
The interpolation type “Linear” (Linear) what it does is maintain a constant speed, linear, as its name indicates, from beginning to end.
What the “Smooth” interpolation does is a slow exit to progressively accelerate to a point where it will slow down to reach the end.
All three arrive at the same moment.
Tips on Kdenlive
If you like Kdenlive, but you don’t use the kde desktop environment and you want to have the Breeze theme (Elegant and above all without display errors) and the dark themes of the interface, and incidentally solve some small display problems derived from using other environments than Kde you can install the following package:
- kde-style-breeze – it occupies with its 0.9Mb dependency (899kb – really for what it occupies it is worth installing it and being able to have the Breeze theme).
- to install it you can do it from synaptic looking for the aforementioned package or from the terminal:
sudo apt install kde-style-breeze
Once installed you can go to the menu “Preferences ⇒ Style” to choose the one you like the most, Breeze looks very good and then in “Preferences ⇒ Theme” you can choose between normal (light color) or “Dark” (dark colors interface).
Personally, the styles that have given me the least display errors have been the “Windows and Breeze Style” with the “Default Theme”.
Thanks for your reading, you can expose any doubt in the comments and as far as I can I will try to solve it.