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Previously we saw that each effect key has a number of modes (by default 8) and that only
one mode can be active for a key at any instant. There are various ways to change the mode of a key,
but first we must look at a concept called the keyboard grab. Keyboard grab is activated by pressing
the "k" key, and it will attach various keys on the keyboard to the last enabled effect key.
For example, if you press ctrl-1. to switch on the effect on that key, and then press "k",
the keyboard is grabbed for the effect key ctrl-1. If you then press ctrl-2 and "k",
the keyboard is grabbed for effect key ctrl-2. Pressing ctrl-1 again followed by "k" will not affect
the keyboard grab, since the ctrl-1 key-press will disable the effect bound to ctrl-1,
and only enabling an effect counts.
If you have the RTE window open, then you can also set the keyboard grab by clicking
in the check box labelled "Key grab" near each effect key.
When the keyboard is grabbed for an effect key, the following keys are then bound to that effect
key. Ctrl-up and ctrl-down. adjust the first numerical parameter of the effect.
Notice that when keyboard grab is off, these keys adjust the playback rate instead.
The "m" key cycles through effects bound to the modes of that key.
The "t" key puts LiVES into text mode. If the effect has a text parameter, all subsequent key-presses
will go to the first text parameter of that effect. An example of this is the livetext effect
and livetext_generator. To leave text mode, press the Tab key.
To remove the keyboard grab, you can do any of the following: Press ctrl-0 (all effects off),
or press ctrl-Backspace (freeze). If the RTE window is open, uncheck the check box marked
"Key grab" next to the effect key which has the keyboard grab.
Above we saw one way of changing the mode of an effect key - first get keyboard grab (k)
and then press "m" to cycle the mode. Other ways of changing the mode are:
With the RTE window open, click on the "Mode active" buttons below each effect key,
or via an external control such as OSC, joystick, or MIDI control.
Just as with rendered effects, we can divide our real time effects into three or more subtypes.
The most common subtypes are effect (one frame input, one output),
transition (two frames input, one output) and generator (no video inputs, one video output).
There are also compositors (multiple frames input, one frame output).
These are only used in the multitrack window, and will be discussed later.
With the RTE window open, you can see the type of each effect in the drop-down list,
and it is also shown next to the key/mode area. Note that the most recent version of LiVES also has
audio effects and audio generators. LiVES can use those effects.
By default, LiVES has transitions mapped to modes of key ctrl-8 and various generators mapped
to key ctrl-9.
If LiVES is not playing and you press the key combination for a generator, this will initiate
playback. A generator is a bit like a clip, because you can apply other effects to it.
You can also now apply a transition and mix a generator with a video clip.
The only thing with the real time generators - when a generator disappears from view, it closes.
For example, start up a generator. Press Ctrl-0 to ensure there are no transitions active.
If you now press ctrl-page-up LiVES will switch to another clip, and because the generator
is no longer visible, it will close.
Some generators also have audio input. If you play audio they will vary their pattern
of behaviour in accordance with the movement of the input audio.
Examples of these are the libvisual generator plugins.
If there is one or more realtime transitions active, then the ctrl-page-up and ctrl-page-down keys
will cycle the background clip. Realtime effects triggered from the keyboard are applied only
to the foreground clip.
In the Clip Editor, you can apply any real-time effects to a selection just as if it were a rendered
effect. Simply select the frames you would like to apply the effects to,
and then click on Effects -> Apply Real Time Effects to Selection, or press the ctrl-e keys.
When the effect is being applied, you can Preview what has been done so far by clicking
on the Preview button.
There is also a Pause button. If you click this you can again Preview what has been processed,
or you can Resume processing. In addition you can choose to Keep what has been processed so far
and not process any more.
Otherwise, simply wait, and the effect should be applied to the selected frames.
Remember that effects can be undone and redone, but there is only one level of undo per clip
in the Clip Editor.
After applying the effects, remember to switch off the realtime effects by pressing ctrl-0,
otherwise they will be applied to the selection twice
(once to the frames, and then again as realtime effects) !
We just saw a moment ago that one way to adjust parameters for a realtime effect is to grab
the keyboard for that effect and then use the ctrl-up and ctrl-down keys to adjust the first
numeric parameter, or the "t" key to enter textmode and change the first text parameter.
Here we will look a little deeper into realtime effect parameters.
One way to see the parameters of an effect is to open the RTE window, activate the effect,
and click on the Set Parameters button. This will open up a parameter window,
and if the effect has parameters you will be able to set them here.
Another way is to set defaults for the realtime effects. This is done by selecting the menu option
VJ -> Set Real Time Effect Defaults, and selecting the effect, transition or generator from
the menu list. Selecting an effect will open up a window, and if the effect has parameters
you will be able to adjust them. If you want to keep the settings, click Set As Default,
otherwise click Cancel.
Setting defaults here only lasts for the current LiVES session, so if you want to make these
defaults permanent, you need to select the menu option... Note that if you set per-key defaults in the
Real Time Mapping window, the per-key defaults override the general defaults which is set here.
VJ -> Save Real Time Effect Defaults can be used to save the defaults.
You can also, as we saw, set default values for a particular instance in the Real Time Window.
Let's see now other VJ keys.
Various keys can be used during playback. These keys can be viewed via the menu option
VJ - Show VJ Keys. Note that many of these keys can be simulated through external controls
(OSC, joystick or MIDI controller for example).
ctrl-left and ctrl-right keys can be used to "scratch" with video.
ctrl-Backspace keys can be used to freeze/unfreeze video.
Audio will continue playing unless the jack audio player is being used, and the preference
Audio follows video rate/direction is enabled. ctrl-space keys reverse the playback direction
- This also works when video is frozen : when you unfreeze it will play in the reverse direction.
Again, direction of audio will change if and only if Preferences
"Audio follows video rate/direction" is enabled in Preferences.
ctrl-up and ctrl-down keys adjust the frame-rate unless the keyboard grab is active,
as we saw before.
ctrl-Enter will return video playback speed to normal.
By default the above keys affect only video, and you can get them to affect audio also, as mentioned,
by selecting either jack or pulse audio playback method and then checking the box
Audio follows video rate/direction in Preferences Playback.
ctrl-page-up and ctrl-page-down keys cycle in both directions through clips.
- This also works when LiVES is not playing as mentioned before. During playback, these keys will
adjust the foreground frame if there are no transitions active, but they if there are one or more
realtime transitions active, then they will adjust the background clip.
By default the above keys only affect video, however if you select the Preferences
Audio follows clip switches then the audio will follow the clip switches too.
The "x" key pressed during playback will swap foreground and background clips.
This only works if there are one or more realtime transitions applied.
You may wish to do this sometimes since realtime effects are only applied to the foreground clip.
So if you wish to apply to the background clip press the "x" key first.
The "n" key during playback toggles Nervous mode. In Nervous mode,
the frame to be played back will jump around a little.
Let's see one more time some keys we already saw in detail previously:
"k" - grab keyboard for last activated effect key.
"m" - cycle effect mode for effect key with keyboard grab.
"t" - enter textmode for the effect that has key grab.
Tab - leave textmode.
If you have several clips open, you can mark the position of a clip with F1 through F11.
For example, if you press F1, the current clip is connected with F1. If you then switch to
another clip, and press F1, LiVES will return to the first clip. All of the keys F1 to F11 can be used
to bookmark clips in this way. This works the same whether LiVES is playing or not.
If you press the F12 key, all bookmarks will be cleared.
Bookmarks only last for the current session of LiVES.
In the Clip Editor, it is possible to record any part of your performance. To initiate recording,
press the "r" key. You can press the key before beginning playback, or at any time during playback.
To end or cancel recording, press the "r" key again, or stop playback.
You can toggle recording on and off multiple times during playback.
If you press "r" before starting playback, you will see a message in the message area informing you
that LiVES is ready to record. If you press "r" again without playing,
you will get a second message informing you that recording was cancelled.
In addition to pressing the "r" key, you can toggle record mode by clicking on the menu option
Play -> Record Performance.
The following types of events are always recorded: frame changes
and fps (frames per second) changes.
Via Tools -> Preferences -> Recording, you can select whether the following types of event
are recorded: Real time effects (including parameter changes), clip switches, audio events.
When LiVES is recording you will see "rec" appear before the frame count in the frame counter.
Once playback finishes, if anything was recorded, a window will pop up asking you what you want
to do with the events that were recorded.
There are various options: Preview the recording. Render the recording to the same clip.
Render the recording to a new clip. Edit the events in the multitrack window.
And view the events in the event window. The latter option is mostly for debugging purposes.
Should you choose to render the events to a new clip, you will be presented with another window,
where you can enter the details of the new clip. Here you can choose the frame size, the frame rate
and the audio details. At this point you can optionally select a target encoder for the clip.
If you choose to do this, LiVES may suggest more optimal values for the frame size, frame rate
and audio values. It is up to you if wish to accept the suggested values or continue with the values
as entered. Note that selecting an encoder here is just for optimisation purposes;
you are still free to choose any encoder/format you like when encoding the clip.
During rendering you can Preview what is being rendered, Pause the rendering, or Cancel.
If you Pause, you can again Preview, Resume rendering or Keep what has been rendered so far.