In this post we will see the tools that Kdenlive makes available to work with images.
Images on Kdenlive
When the images are individual, to make a photo slideshow or to insert them together with a video, they are uploaded to the project exactly the same as videos or audios. Either from the project folder wizard to add files or by dragging them directly from their location to the aforementioned project folder.
Images are inserted directly from the project folder to the timeline; the duration that is predefined by default is 5 seconds (this can be changed in the wizard to configure Kdenlive) but we can easily increase or decrease this directly on the timeline by stretching or shrinking the image clip from its ends.
Everything seen in the previous entries about effects and transitions is valid for images and works exactly the same way. In fact, in the entry of the transitions we already saw some examples of how these worked on images.
Kdenlive accepts the most common formats such as .bmp .gif .jpe .jpeg .jpg .pcx .png .ppm .tga .tif .tiff. Also supports vector graphics .svg
In Kdenlive we can make image presentations in two ways:
- manually inserting the images individually with the animation and transition that we want to each image or
- automatic using the “Add Slideshow” wizard
Preliminary considerations on working with images
When the images are in high resolution, it is advisable to reduce them to a size equal to the resolution that we are going to use in the video. This is to save resources, since working with 4500x2530px images for 1920x1080px Full HD video is unnecessarily overloading memory.
In a presentation of photographs (where it is likely that we will make small enlargements to make slight panoramas) it is recommended to reduce these to a size 10 or 15% above the resolution of the project. For example, in a FullHD 1080 project (1920 × 1080 resolution) the images that we have, for example, at a resolution of 4160x2336px, we will reduce them by 10% above the value of the project, leaving these at 2112x1185px. which allows us a margin of expansion more than enough to make our presentations.
An exception to what is cited in the previous paragraphs would be when we intend to greatly enlarge an image to highlight a detail of it; in these cases it is better to leave them in high resolution so that they can be enlarged a lot without getting pixelated.
When we have small images to make a presentation, it is better to make a composition with the images in real size on a background, or a collage, since if we enlarge them they can blur and pixelate. To carry out this type of montage we will have to make use of a transformation effect using the option “Adjust to original size” and placing the images on the screen in the way that we like the most.
In images with a different aspect to the one used in the project, for example 4: 3 images in a 16: 9 project, to avoid empty spaces on the sides, we can put a colored background or make a composition like the one seen above.
“Add Slideshow” Wizard
Kdenlive offers us a wizard designed to quickly make photo presentations called “Add presentation clip”.
What this tool does is create a video clip with the images that we have in a folder with the possibility of using transitions and animations.
Once this clip is created, its insert operation is exactly the same as any other clip, it is actually another video clip made up of images.
To access this we do it from the project folder, either from the icon or by right-clicking on the blank space.And the following wizard will open where we can configure our image clip:
Once we have chosen the folder where the images are and configured the wizard to our liking, we only have to press OK and a presentation clip (MIME Types) or a sequence (Pattern) will be created in the project folder.
At any time by double clicking on the sequence or presentation that has been created in the project folder (or by right-clicking on this clip and choosing “Clip properties”) we can access the configuration wizard to change what we want or activate filtering, in the case of presentations, if we have used an animation method for its export.
To add images to this presentation, simply put these in the folder that we use to create it and enter the clip properties (double click to open the wizard) and we will see that these come out along with the ones that were already in them, following alphabetical or numerical order. Just OK and the presentation will be updated with the new images. If we want to remove one or more images, simply remove them from the folder and re-update the clip by entering its properties. Be careful with these processes if we already have this clip in the timeline because it will be affected.
I have noticed that sometimes in the preview the transitions or sweeps show a wrong white background; to be sure I have made an export that introduced some transitions and everything has gone as it was. I quote it to remind us that when something out of the ordinary is observed, it is best to do an export test of a few seconds to get rid of doubts and not waste time in the preview if the export goes well.
Pros and Cons of Using the Presentation Creation Wizard (MIME Type)
- Its speed compared to doing them manually.
- All images grouped into a single clip.
- In case of using fades, sweeps and / or animations, this will always be the same animation in each image, which can become monotonous if the presentation is long.
In the case of long presentations, what can be done is to divide the images into different folders (for example, 50 images divided into 10 folders of 5 images each) and adjust the animations, fades, and sweeps in each clip differently.
If we make a presentation without using the wizard, we can insert the effects and transitions we want to animate each image.
We have two ways of making photo presentations, with the assistant or manually, but we can also combine both options in long presentations.
As with any clip, we cannot move or rename these folders. Although Kdenlive has a wizard to locate clips that have been moved or renamed.
What we can do, as I have mentioned above, is to add or remove images from said folders and even change their order if we wish. Caution as these changes will affect clips inserted in the timeline.
Recommendations for presentations by uploading the photos individually
We can make use of all the video effects, transitions and layer blending modes to animate our presentation.
Two effects that go very well to animate photographs are those of the “Crop and transform” family called “Position and zoom” and “Transform”, both animatable. The most complete of the two is “Transform” since, in addition to being able to animate the position and scale, you can also use and animate the rotation and opacity.
The effects of the “Distort” family are interesting if we want to distort the images. (More information in the article on the effects)
The transitions are all interesting. In the article in which I talked about them there is an example with each of them in the video.
Highlight those of “Related”, “Compose” and “Region” for their wide range of functionalities and the possibility of animating.
The “Slide” for its simplicity and “Sweep” which is a type of transition widely used in image presentations.
Anti-Flicker Filters (Image Flicker)
What an anti-flicker filter (“Remove Image Flicker”, “Flicker Filter” or simply “deFlicker” does. In Spanish, commonly referred to in audiovisual slang as “Image Flickeo”) is to apply a subtle and invaluable (in theory) blur to the images, thereby eliminating the annoying flickering produced by some videos or images when we animate them. In still images this problem does not occur.
We have seen that the animation section of the “Add presentation clip” wizard has the possibility of using filtering, which is nothing more than a low-pass anti-flicker filter. But what if we don’t use the assistant and we have an image that flickers when animating it? Or if despite using the assistant the problem is only in one image and we do not want to blur the others?
Kdenlive has three effects that can help us solve the first question and of these three there is one that solves both.
The one that solves both questions is the effect “Blur“Of the” Blur and hide “family and precisely solves both questions because it can be animated, so we can apply it both to an individual image and animate it in a certain fragment of the clip, which acts only where we have the problem when it is a video or slideshow. This effect is what the “Add Slideshow” wizard uses.
The other two that we can use is that of “Medium”From the“ Blur and hide ”family and the“Smartblur“Which is part of the” Varios “family. The latter has surprised me by how good it is, it does its job very well in terms of correcting flicker, it blurs very little and consumes much less resources than blurring. Undoubtedly Smartblur is the best for this task.
The values that are recommended in all three are those that come by default when we open them; In the Blur to be able to animate it, we can play between the value 0 to deactivate it and 40, which is the one that comes by default.
How do we assess whether we should apply this type of filter? It must be taken into account that in the previews we may be seeing flickers that are not really present in the final export; then the best way to assess if we should filter is by exporting the seconds of the fragments where we observe the problem and if it persists in the export, then if we must make use of these effects.
Example of an “Image Pattern”
I have already mentioned that a pattern or sequence of images is nothing more than a video broken down to its minimum expression, that is, one image per frame. Next I am going to make an example of what would be a sequence of images of a background for titles that I have created in Gimp.
This animation is 10 frames long, so this animation has been made with ten layers in Gimp and each layer has been exported as a sequentially numbered frame from start to finish. We have made two versions, one input and one output.
The frames have been made in Gimp on a frame with the same size of the project, if this is HD1080 in Gimp we will have created this animation with images with a size of 1920x1080px with a transparent background.
The objective is to make a fund for titles, called a tablet in audiovisual slang. As it occupies only a small portion of the screen, the rest will be transparent, so we will use an image type that supports transparency (Alpha channel), as is the case with * .png images.
Kdenlive has a feature to invert videos, but it does not work with image sequences. For this reason I have made two versions, one input and one output (both 10 frames); in this case it is the same animation but inverted. This is sometimes not the case and different animations are made for entry and exit.
This image is a collage of what the ten input frames would be (the output is the same but reversed).
In Kdenlive I have simply added a “Presentation Clip” with the “filename pattern” option selected.
In folder I have navigated with the assistant to the folder where I have the 10 frames of the input animation and I have selected the first one. With the output pattern I have done exactly the same. And in this way we already have the patterns in the project folder. I have called one “In” and the other “Out”
We already have the entry and exit animation. In sequences, when stretched, the last frame does not remain in the background; In this case, what I do is load frame 10 of the input animation as a single image and this will be the one that will be the background for the time required.
This title background enters in 10 frames, then it is held for 3 seconds 5 frames and it goes in reverse of how it has entered (also in 10 frames). Its total duration is 4 seconds.
Next I put a gif that emulates the result. The time that the base is kept is reduced, the idea is to see the entry and exit animation.