Shotcut Video Filter: JRtransition

Author: Elusien©2019 (www.elusien.co.uk/shotcut) Licence: MIT

JRtransition is a Shotcut Video Filter that produces a nice transition between video clips. This filter has been developed from an original idea of Shotcut Forum member "jonray". It is especially useful as a transition between slides of a slideshow. There are various ways to use this filter which are described below.

Filter Parameters
Name Description
Framerate The framerate of the exported video, input as the number frames per second. You must specify this correctly if you use "seconds" as your units for 'duration"; if you use a "negative percentage" value for "duration" instead the framerate value is not used.
Delay The amount of time to delay before the transition starts. The delay can be specified in one of two ways, either as a negative percentage or as a value.
  • If it is specified as a positive value (or zero), this is taken as meaning the number of seconds to delay.
  • If it is specified as a negative percentage, this is taken as the percentage of the the time taken by the clip. e.g. -100% means the whole amount of time taken by the clip to which the filter is applied.
Duration The amount of time taken to perform the transition. Again as a negative percentage or a value
Angle The angle (between -60° and 60°) at which the transition slopes.
Direction The direction (top, right, bottom, left) from which the transition starts.
Main color The colour of the wide stripe.
Stripe color The colour of the thin stripe.
Chroma When selected, the effect is an animated chroma key (or greenscreen) that matches the timing of the thin stripe.
Reverse When selected the Chroma key or Mask are reversed e.g. instead of the chroma color appearing and travelling across the screen, it already exists on the screen and disappears as it travels across the screen
Mask When selected, the effect is an animated (black and white) matte or mask that matches the timing of the thin stripe.
Chroma color The colour of the chroma key. If your clips contain a lot of green (#00ff00) use this parameter to choose a different chroma key colour.

Download: ZIP file

Instructions

  1. Download the ZIP file above, either by clicking it, or right-clicking and choosing "Save target as";
  2. Extract the Zipfile into your Shotcut filters folder (directory), which is beneath the folder in which Shotcut is installed. For example on Windows systems it may be:
     C:\Program Files\Shotcut\share\shotcut\qml\filters 
    while on linux it may be:
     /usr/bin/shotcut/share/shotcut/qml/filters 
  3. Start Shotcut and the new filter will appear in the list of video filters.

Description of Use

There are several ways of applying this filter.

Static images (slideshow)

Say you have a set of slides (static images) you want to turn into a slideshow and say that each slide shows on the screen for 4 seconds, then the JRtransition takes a further 2 seconds to create a seamless transition into the next slide (as shown in the schematic below).

schematic

You would do the following:

  1. Apply the filter to each clip on track V2 with the parameters delay=4, duration=2, chroma selected
  2. Apply the CHROMA KEY SIMPLE filter to each clip on track V2 (you may need to adjust the "depth" parameter)
  3. Apply the filter to each clip on track V2 with the parameters delay=4, duration=2
  4. If you are not using Shotcut version 12.06.15 or higher, apply the filter to each clip on track V1 with the parameters delay=4, duration=2

This method only works because the clips are static images. If the clips are not static images, but video clips instead, use the next method.

Motion (sets of video clips)

Say instead you have 3 clips of non-static video footage of various lengths and you want to have the JRtransition between clips 1 and 2 and between clips 2 and 3 (as shown in the schematic below).

schematic

You would do the following:

  1. Split clip 1 at its 5th second (let's call the second part clip 1A)
  2. Split clip 3 at its 3rd second (let's call the first part clip 3A)
  3. Apply the filter to each 2-second clip on track V2 (1A and 3A) with the parameters delay=0, duration=-100, chroma selected
  4. Apply the CHROMA KEY SIMPLE filter to each 2-second clip on track V2 (1A and 3A)
  5. Apply the filter to each 2-second clip on track V2 (1A and 3A)with the parameters delay=0, duration=-100

However, when you apply the JRtransition filter to the beginning of a track on V2, such as 3A, you must reverse the direction of the chroma key by selecting the "reverse" option.

If you are using a version of Shotcut prior to version 19.06.15 the above procedure will almost give the correct effect, but there will be a slight problem with transparency. There were changes to the use of the alphachannel with transparency at that level of Shotcut and above. For versions prior to this one you have to include a few more steps:

  1. Split clip 1 at its 5th second (let's call the second part clip 1A)
  2. Split clip 3 at its 3rd second (let's call the first part clip 3A)
  3. Split clip 2 at its 11th second (let's call the second part clip 2A)
  4. Split clip 2 at its 3rd second (let's call the first part clip 2B)
  5. Apply the filter to each 2-second clip on track V2 (1A and 3A) with the parameters delay=0, duration=-100, chroma selected
  6. Apply the CHROMA KEY SIMPLE filter to each 2-second clip on track V2 (1A and 3A)
  7. Apply the filter to each 2-second clip on track V2 (1A and 3A)with the parameters delay=0, duration=-100
  8. Apply the filter to each 2-second clip on track V1 (2A and 2B) with the parameters delay=0, duration=-100

As shown in the schematic below. Again you will have to select the "reverse" option if the filter is applied to the beginning of a track on V2.

schematic NOTE

There have been some problems reported with "glitches" that occur when using the above mentioned procedure for motion (video clips). This may be related to "reversing" the chroma key. If this is the case for you you can use another method which is shown pictorially below. You do the following:
This problem has now been fixed, but the procedure below is still a valid one.

  1. Split clips 1, 2 and 3 as shown.
  2. Move the respective 2-second clips (2B and 3A) onto track V1
  3. Apply the filter to each 2-second clip on track V2 (1A and 2A) with the parameters delay=0, duration=-100, chroma selected
  4. Apply the CHROMA KEY SIMPLE filter to each 2-second clip on track V2 (1A and 2A)
  5. Apply the filter to each 2-second clip on track V2 (1A and 2A) with the parameters delay=0, duration=-100
schematic

Customising the filter

Don't forget, if you are customising the filter (e.g. setting a different color for the stripe or a diiferent angle) you can save these as a new preset. That way you won't have to keep changing these values each time you apply the filter.

Screenshot

Video