Overview

Movie Processing in Studio Artist is achieved by building a processing script called a Paint Action Sequence (PASeq) and then processing a video file with the PASeq to generate a new effect rendered output movie.  The individual action steps recorded in the PASeq work together to build up a particular artistic effect. The Paint Action Sequence palette shown above is accessible from the main Windows menu and is where you record and edit a PASeq.

You can open a source movie in Studio Artist’s source area and work with a single frame of your source movie to build and record a PASeq.  When PASeq recording is turned on any processing actions (manual or automatic) you perform in Studio Artist will be recorded as individual action steps in the PASeq. When finished recording you PASeq, you can then run one of the Action menus to process a movie file (or folder of numbered frame images) with the PASeq to render out your new processed output movie file.

For more information on recording custom paint action sequence and processing a movie file with it check out this tip.

Building a Paint Strategy

Every successful paint action sequence is built up from implementing some kind of paint strategy. A paint strategy can be thought of as the set of steps necessary to build up a particular visual effect. An artist always follows some kind of a strategy or plan to build up an artistic image. The combination of all of the steps in the strategy act together to generate the desired visual effect.

When processing video there are additional perceptual factors to take into account besides the artistic appearance of a single image.  A video is composed of a series of frame images presented sequentially over time. When processing a series of video frames you need to be aware of how any image processing or painting you are doing is going to look when the processed video frames are sequentially presented to a viewer as the rendered video file plays back.

One important part of any paint animation sequence involves what to do with the animating canvas background. There are several different approaches to this component of a paint strategy for building a paint animation. The traditional thing to do would be to erase the background of the canvas to white before drawing each frame. This simulates traditional paint or sketch animation where the animator always draws on a clean piece of paper.

A visual side effect of erasing the background each frame is that the resulting animations usually have a perceived flicker. This is especially true when an animation is built up from generic autopainting within Studio Artist. There may not be any real visual continuity between paint strokes from frame to frame when autopainting with some arbitrary paint synthesizer preset.  If there is lack of temporal continuity from painted frame to frame then that results in perceived flicker in the processed output movie when you watch it.

The paint  strategy you will follow when building your paint action sequence depends on what you are trying to achieve stylistically in a given animation. If you want it to look like it was hand drawn animation, then a style with some visual flicker from frame to frame might be just what you want. If you don’t, then there are various strategies to use to eliminate flicker in a paint animation.

Eliminating flicker involves introducing some form of temporal continuity from frame to frame. By temporal continuity we mean that there is some visual coherence between sequential frame images in the output movie. One approach to generating temporal continuity in an animation is to modify or transform the previously painted output frame in some fashion, and then paint on top of the modified canvas.

Making sure that individual paint strokes have continuity from frame to frame is important for generating temporal continuity. Painting on top of the previous output frame is one way of doing this. But you could also use other techniques like time particles or bezier path interpolation to build paint stroke continuity from frame to frame in an animation.

Building paint paths from source frame features (like edges) is also an approach that can work well for reduced flicker in paint animation. This is because paint strokes that track the edges in the source video frames will track the object movement taking place in the video over time. A technique like this can be used in conjunction with overdrawing on a modified previous output frame image to reduce or eliminate flicker.

Many Studio Artist paint presets also incorporate various kinds of randomization to help achieve a more organic paint look.  This can take the form of color randomization as well as modulation of different characteristics of the paint paths and brush over the drawing of a single paint stroke as well as over the course of drawing multiple paint strokes.  Sometimes you need to dial back or eliminate artistic randomization effects in a paint preset when processing video to avoid introducing temporal variance from frame to frame.

Typically you will be working with source video that is 24 or 30 frames a second.  But traditional animation is often generated at a lower frame rate. Reducing the frame rate of an animated output sequence (like to 10 – 15 fps) is another great way to reduce the visual perception of flicker. Studio Artist has movie preferences you can use to automatically skip source frames when processing with a PASeq if you want to reduce the output frame rate without stretching out the timing of the resulting animated movie.

Another key point is that often a successful paint strategy and it’s associated paint action sequence can be a combination of paint effects and image processing effects. One of the strengths of Studio Artist is that you can combine together different paint effects, image processing effects, warping or morphing effects, region masking, and resolution independent texture synthesis within a given paint Action Sequence script. Most successful animations are based on scripts involving several different paint or image processing presets that work together to build the particular desired effect.

Wet Flow Paint Animation Example

Here’s an example of a simple paint animation effect i put together to showcase some of the principals of building a paint strategy as discussed above. The PASeq incorporates overdrawing on a modified previously painted canvas (as opposed to erasing the canvas at the beginning of each new frame). I was trying to achieve a rough fairly abstract paint style with some liquid flow in the background. I also didn’t want the painting to be so abstract that you couldn’t distinguish what the original source content was.

Click here to view the embedded video.

The video example above shows off the end result of my iterative design process to build the desired paint animation style i described above.

I started by choosing a rough paint preset that focuses on laying down paint in high texture regions of the source image.  I then recorded four paint passes using this preset with progressively smaller brush size for each pass. My initial PASeq (shown below) also erased the canvas to white before painting each frame.

The video example belows shows what you get when you process the skater source video with this initial PASeq.

Click here to view the embedded video.

Because the canvas is first erased to white for each frame prior to painting it in there’s a fair amount of visual flicker associated with the paint animation.

My next attempt at modifying this initial PASeq was the one shown below. A black mute keyframe was inserted at frame 2 of the first Set Canvas – White action step in the PASeq list. You hold down the m hotkey while option clicking a keyframe to record a black mute keyframe. I then choose a radial flow canvas spreader paint preset and used it to spread the paint strokes on the canvas out from the center towards the edges.  After recording this additional paint step into the PAseq i then dragged it at the top of the PASeq list right after the initial set canvas to white action step that only runs for the first frame of the animation.

So this PASeq erases the canvas to white for the first frame only.  The canvas is then spread out by the flow paint, and then the original paint steps that draw in the skater take place. Since the canvas is not erased except at frame 0 the previous output frame will always be in the canvas when the next frame starts drawing. The video example belows shows what you get when you process the skater source video with this second PASeq.

Click here to view the embedded video.

I liked the fact that overdrawing on top of the flow modified previous output frames reduced the visual perception of flicker in the resulting paint animation. But i felt that the foreground of the moving skater was a little hard to distinguish from the smeared paint background. So, i introduced an additional processing step that modified the previous output frame by  slightly hue shifting it. The modified PASeq with the addition of a HueShift image operation action step is shown below.

The video example belows shows what you get when you process the skater source video with this third PASeq. Note how the addition of the hue shift step helps to distinguish the foreground from the background.

Click here to view the embedded video.

At this point in designing my paint strategy i wanted to make the source video features a little more recognizable in the paint animation.  And i wanted to reduce the emphasis of the flowing smeared background a little and increase focus on the foreground painting.  I also decided to start with a black background instead of a white background.  My final PASeq for my iteratively designed paint strategy is shown below.

Once again, here’s the final paint animation video below generated with the final PASeq shown above.

Click here to view the embedded video.

Note how i worked iteratively to build my final paint strategy.  I took my initial goals and worked to build my paint action sequence step by step to achieve those goals. This is usually a more effective way to work than trying to do everything in a single pass, especially when just getting started with Studio Artist. As an experienced Studio Artist user i find that i still modify and tweak my initial PASeq designs to hone a particular effect and to fine tune it to the characteristics of my source video.

Being organized and focused on building the different components of your desired paint strategy step by step is the best way to build your own custom paint animation effects. Don’t be afraid to experiment.  You can always delete a recorded PASeq action step if you’re not happy with what it’s doing. You can also export PASeq presets as you’re working, so that you can go back to a particular iteration of the effect if you get off track in your design process.

Getting Started

Studio Artist comes with thousands of different paint synthesizer and PASeq presets to get you started. They are arranged in different Collections and Categories. All of the presets are completely editable, so you can modify them or build your own. If you don’t want to build your own, you can use the ones we provide to get started. If you want to build your own, there are an unlimited number of presets that can be generated within the program by custom editing your own presets.

Combining together different paint presets and image processing effects within a paint action sequence is how you build up a particular paint strategy. Don’t be afraid to experiment.  Often it’s best to start out fairly simple and then add additional action steps one at a time to build a more sophisticated effect.

Where to go from here

We have provided a tutorial folder of specific paint action sequence presets in the Process Movie Tutorial category designed to show off a series of different simple paint strategies.  The Process Movie Tutorial pdf helps explain how these different PASeq presets were built. This particular set of tutorial PASeq presets is a little old but still useful for getting started with building PASeqs for movie processing.

The presets i described above are included in the newer Movie Processing Strategies category. These PASeq presets showcase some additional version 4 features that work well for movie processing.

For some additional information on the mechanics of processing a movie file with a paint action sequence check out this tip.

This tutorial is the first part of a series of tutorials on building paint strategies for processing movies. The second part of the tutorials is available here. The third part of the tutorials is available here.

The PASeq presets used in this movie processing tutorial series are available for download here.

How to generate a morph

To start off, open the Paint Action Sequence (PASeq) editor and erase the current PASeq by pressing the Erase button in the PASeq editor toolbar.

Choose the first source image you will be using for your morph sequence and open it as the current source.

Then, record a Morph Context action step by running the Action : PASeq Timeline : Record Context : Morph menu command.

After running this menu command you will see a single Morph Context action step recorded in the PASeq editor.

Now switch to Bezier Draw operation mode. An easy way to do this is to use the Operation : Bezier : Bezier Draw menu.

Once you are in Bezier Draw op mode, you can draw in a series of Bezier paths that will anchor features in your source image.  Turning on the source onion skin is a good way to do this. Or you could drag the source image into the canvas if you wish.

For example, if you are morphing a series of faces, try drawing a series of Bezier paths around the facial features like the eyes, nose, mouth, and head.

When you are done drawing your set of Bezier anchor paths, option click the first keyframe in the Morph Context action step in your PASeq Timeline.

Now choose your second image for your morph and open it as the source image. The onion skin will turn off when you open the new source image, so turn it on again. Now switch to Bezier Edit op mode.

Note how the original Bezier anchor paths are still displayed, but they no longer correspond to the facial features of your new source image.

You now need to edit the existing Bezier paths so that they correspond to their associated facial features in the new source image you just loaded. An easy way to do this is to use the new e hotkey function available in Bezier Edit. 

First select a single Bezier path. Then hold down the e hotkey and redraw the selected path where you would like it to be located. The old selected path will vanish and appear as the new path you just drew in.

You can now quickly select the remain paths one by one, and then redraw them in their new locations while holding down the e hotkey.

Once you have edited all of the old anchor paths to their new locations, option click a new keyframe in your Morph Context PASeq action step.

At this point you’ve defined a morph between 2 still images. The frame capture below shows the mid frame of the simple morph we defined in this example between the 2 face images.

You can continue adding additional morph context keyframes for additional source images if you want to morph between a series of images. For each additional image, you would open it as the source image, edit the Bezier anchor paths to correspond to the new source image, then option click record a new morph context keyframe.

Generating a morph animation movie file is the same as generating an animation movie from any other PASeq.  You just run the Action : Animate with Paint Action Sequence : to Movie menu command.

A Bezier morph animation example created using the same technique described above with a different starting source image is below:

bezier morph example

Bezier Warps or Filtering

Bezier warps or Bezier defined spatially variant filters are created using a similar technique to that described above.  They use Warp Contexts or Filter Contexts depending on whether you are warping or filtering.  As described above, the movement of Bezier paths over time defines the warp or spatially variant filter operation.

By using the series of steps described in this tip you can automatically generate a sketch or other paint style animation from a series of still images with no manual drawing.

Recording your source context keyframes

The first thing to do is to record a Source Context PASeq action step with a keyframe for each of the still images you are interested in painting in your animation. To do this, first erase the current PASeq. Then choose the first source image you want to use in your animation. Then run the Action  : PASeq Timeline : Record Context : Source menu command. 

A Source Context action step will be recorded in your PASeq after running this menu command.

You can then open a new source image and option click a keyframe in the PASeq timeline associated with the Source Context action step. Continue this cycle until all of your source context keyframes are recorded. If you click on a source context keyframe you will see the source image change to the one stored in the keyframe you clicked.

A shortcut way to record multiple source context keyframes is to use the Action  : PASeq Timeline : Record Context : Multiple Keys : Source menu. This menu command brings up a dialog that lets you choose multiple source images one at a time. After pressing cancel a source context action step will be generated with adjacent keyframes for all of the source images you selected.

Record your Bezier generation steps

You’re now ready to record your desired sequence of PASeq action steps to generate a set of Bezier paths for your animation. There are a large number of different approaches you can take to generating a set of Bezier paths. You could use one of the Path : Generation menus (the source edges option for example). You could generate Bezier paths from one of the Ip Op Sketch effects. Or you could use one of more action paint steps to generate Bezier paths associated with a particular painting style.

Make sure the first step in your Bezier path generation process is to erase the current Bezier path frame. Whatever approach you take to generation a set of Bezier paths, the steps are added to the existing PASeq with the source context keyframes.

Generating a Bezier Context

Once you have recorded your PASeq actions teps that generate Bezier paths, you can automatically run the PASeq on all of the source context keyframes and generate a bezier context that has keyframes ar all of the associated frame times. To do this, first select the source context action step. Then run the Path : Convert to Paint Synthesizer : Convert PASeq Source Context to Bezier Context menu command.

When you run the menu command the PASeq will be run for each of the source context keyframes. After running through all the keyframes then a new Bezier COntext action step will be recorded at the bottom of the existing PASeq. You can drop into Bezier operation mode and press one of the Bezier Context keyframes to see the set of Bezier paths stored in it.

Generating the encapsulated paint step

Once you have a kyeframed Bezier context, it’s easy to convert it into an encapsulated paint actions tep in the PAseq.  First choose the paint preset you want your Bezier animation to be drawn with. Then select the Bezier Context action step in the PASeq you will be converting. Then run the Path : Convert to Paint Synthesizer : Convert PASeq Bezier Context to Embedded Autodraw menu command.

The Bezier context action step you selected will change to a keyframed paint action step after running the menu command. Each keyframe will paint the set of Bezier paths that were originally encoded at that keyframe in the original Bezier context.

At this point you now have an encapsulated keyframed Bezier paint animation. You typically would now run an Action : PASeq Timeline : Embedded Bezier Frame : Normalize Split  and an Action : PASeq Timeline : Embedded Bezier Frame : Reorder Minimal Distance menu command. Running these 2 menu commands will insure that each keyframe has the same number of bezier paths for the keyframe interpolation, and that the interpolation takes place between adjacent paths that are close to one another, leading to a smoother animation.

You could now render your animation to a movie file using the Action : Animate with Paint Action Sequence : to Movie menu command. The normalize, reorder, and animate menu steps briefly described above are explained in more detail in this previous Bezier encapsulation paint animation tip.

The following movie example shows off a simple pencil sketch animation that was fully automatically generated using the techniques described above from 4 source keyframes using 2 Sketch Ip Op effects to generate the Bezier paths for encapsulation and a pencil paint preset to sketch the encapsulated Bezier paths.

pencil sketch animation

This tip discusses how to create a keyframed paint animation from a series of freely sketched pencil sketches. Each sketch can have an arbitrary number of pencil strokes. Each sketch is encapsulated into a single paint action step recorded in a Paint Action Sequence (PASeq). The final animation is generated by animating the keyframed single step PASeq into a movie file. By working with keyframes as opposed to hand drawing each frame in the animation you can generate a completed animation in a fraction of the time it would take to draw each frame manually.

Bezier encapsulation is a powerful feature of Studio Artist. Bezier paths are vector paths that underly each paint stroke in Studio Artist. Each layer contains a Bezier path frame in addition to a raster frame buffer. A set of multiple Bezier paths can be encapsulated into a single paint action step, and the bezier paths can then be keyframed in a PASeq timeline.

This tip will discuss how to generate keyframed animation from encapsulated bezier paths. One nice feature associated with encapsulated bezier paths is that an entire drawing composed of multiple paint strokes can be recorded into a single paint preset or paint action step in a PASeq. There are also PASeq Timeline menu commands that can manipulate encapsulated bezier paths so that a series of sketches made with arbitrary number of paths can be configured to smoothly animate over time.

Making your first sketch

The source onion skin is a useful feature that can be used as an aid when manually sketching a source image. I used a source onion for all of my keyframed sketches in this example.

To start, load the source image you want to use as your first sketch. Make sure the canvas is the size you want it to be for your animation.  You can either do this by using the File : New Source and Canvas menu to load your source image and resize the canvas in one step, or you can use the Canvas : Resize Canvas menu.

Make sure the Canvas : Onion Skin is set to Source and then turn on the onion skin by either running the Canvas : Onion Skin : Toggle Onion Skin menu or running cmnd t which is it’s keyboard shortcut. You should see a semi-transparent view of the source image in your drawing canvas, this is the source onion skin.

Nw choose the paint preset you will be drawing with. I used the Default : Pencil : Round1 paint preset, which draws like a soft graphite pencil.

Make sure the paint preset you are working with does not have any path randomization. You can check this by going to the Path Randomize control panel in the Editor palette and making sure both Displace options are set to None. Path randomization interferes with the Bezier path conversion process, so you should avoid it if working with Bezier encapsulation.

Since we want to record the bezier paths associated with our drawing, we need to make sure the Path : Path Layer Record Options : Pen Draw menu flag is turned on. When this menu flag is turned on then any manual drawing will be converted into Bezier paths and the paths will be stored in the current Bezier path frame.

Erase the canvas before drawing to white. You want to make sure you do a full erase, so make sure the default color is set to white and then shift click the erase button in the main operation toolbar. Shift clicking erase runs a full erase, which also erases the Bezier path frame for the layer in addition to erasing the raster frame buffer to the default background setting (white in this case).

Now draw a simple free sketch of the source image. Only what you draw will show up in the final sketch, the onion skin is there for a guide only. When you are finished sketching you can turn the onion skin off (run the Toggle Onion Skin menu discussed above).

To verify the Bezier paths associate with your drawing were recorded into the Bezier path frame switch to Bezier operation mode. You should see the paths appear on top of your sketch strokes. A shortcut to drop into and out of Bezier operation mode is to use the cmnd 5 keyboard shortcut.

Switch back to paint synthesizer operation mode. make sure you haven’t changed the paint synthesizer from the preset you were using for your sketch drawing. We’re now ready to encapsulate the recorded Bezier path frame into a single pain action step.

Bezier Encapsulation

To encapsulate the recorded Bezier paths in the Bezier path frame into the current paint synthesizer preset, you run the Path : Convert to Paint Synthesizer : as AutoDraw Embedded Bezier Frame menu.

This menu command captures the contents of the current Bezier path frame into the internal Bezier memory in the paint synthesizer. It also runs a paint synthesizer macro edit that configures it’s editable parameters so that it will play back the paths stored in it’s internal path memory.

Now we’re ready to record the encapsulated paint preset in a Paint Action Sequence. Open the PASeq palette and erase it’s contents by pressing the erase button in the toolbar at the top of the PASeq palette. Turn on recording by checking the record checkbox in that same toolbar. Then press the action button. The encapsulated paint step should now playback your sketch and a single paint action step should record in the PASeq. Turn off PASeq recording by unchecking the record checkbox.

Recording the remaining keyframes

You can now record the remaining keyframes associated with your sketch animation. You will perform the following cycle of steps for each remaining keyframe.

1. open a new source image
2. turn on the onion skin
3. perform a full erase of the canvas
4. draw you sketch
5. switch to bezier operation mode
6. option click a PASeq keyframe cell to record the keyframe

I prefer to record adjacent keyframes, and then use the Action : PASeq Timeline : Time Compress/Expand menu command to expand the timeline when i have finished recording all my keyframes.

Generating an animation movie from your recorded keyframes

Since i wanted to have the PASeq erase the canvas first for each frame and then draw the sketch, i recorded a second PASeq action step that sets the background to white. I did this by turning on PASe recording, pressing the erase button, turning off PASeq recording, and dragging the recorded Set Canvas- White action step to the top of the list.

The screen snap below shows my finished PASeq for the animation. I recorded 4 keyframes associated with 4 sketches. I wanted to have 10 frames between each keyframe, which leads to a total of 31 frames in the animation, since keyframes are recorded at frames 1,11,21,31.

At this point you can generate an animation movie from your recorded PASeq. To do this you run the Action : Animate with Paint Action Sequence : to Movie menu. This menu will ask you to name the generated movie file and will then run the animation rendering the frames out to that movie file.

If you just want to preview the animation without rendering it to a movie file you can just press the Animate button in the PASeq toolbar. You can always use the spacebar to stop an animation or a rendering movie process.

If you now watch the generated animation movie you will notice a few problems associated with it.  The animation between keyframes will not appear to be smooth, and there will be abrupt jumps at keyframe points where paint strokes jump into or out of existance.

There are 2 reasons for the problems associated with the animation. The first is that each keyframe was recorded with an arbitrary number of sketch strokes. But to have a smooth animation we would want to have the same number of paint strokes for each sketch. The second reason is that the stroke transitions between keyframes are totally arbitrary, when ideally we would want spatially adjacent paint strokes in adjacent keyframe times to interpolate.

The solution to both of these problems is to run some Action : PASeq Timeline menu commands on our recorded PASeq prior to rendering out the final animation. The first menu to run is the Action : PASeq Timeline : Embedded Bezier Frame : Normalize Split menu. Both normalize command options insure that each keyframe in the PASeq timeline has the same number of embedded bezier paths. Normalize Split splits the longest paths to normalize the path count. Normalize Recycle duplicates paths.

The second menu command to run is the Action : PASeq Timeline : Embedded Bezier Frame : Reorder Minimal Distance menu command. This menu command reorders the path indexes of the recorded paths to insure that the interpolated paths are spatially adjacent, which leads to a smoother animation. This second menu command may be slow to run if you have a large number of embedded Bezier paths or a large number of keyframes.

3 movie examples are shown below. The first is the original keyframed animation. The second is the split normalized animation. The third is the reordered by minimal distance animation.

original animation

split normalized animation

minimal distance reordered animation

Watching each of these 3 animations should give you a feel for what the various processing steps do.

If you want to create even smoother animation, you can break your sketch up into parts and record each part as a separate PASeq action step. Each of the action steps will have associated keyframed encapsulated Bezier paths. For a face ketch, you could break the sketch up into action steps for each of the facial components (eyes, nose, mouth, hair). Building the sketch this way insure that the keyframe interpolation will only be associated with the transformation of each facial part and not transforming between parts, leading to smoother automatic motion of the component paint strokes.

You can also generate alternative keyframed Bezier animations based on various automatic path generation operations, like generating the sketch paths from the source edges. One advantage of this kind of approach is that there’s no manual drawing, the entire process used to generate the animation is fully automatic. There’s a tip that describes how to do this in more detail.

If a paint stroke length of 1 is used for time particles then an individual particle will be a single paint nib moving in time. If the paint stroke has a length greater than 1 than a complete paint stroke will be associated with each time particle. Depending on the settings of the time particle parameters in the paint synthesizer, a rigid paint stroke may move in time or the moving paint stroke may also be recalculated and redrawn in each new frame.

The movie example ‘motion-drops1′ shown in the link below shows off a simple use of time particles in a paint animation. 

motion-drops1

This example was create using a 2 step Paint Action Sequece (PASeq) that will be detailed below. 

A simple paint preset was edited to turn on time particles as shown below in the Time Particles 1 control panel in the paint synthesizer.

The movement of the individual time particles over time is primarily defined by the editable parameters in the Time Particles 2 control panel in the paint synthesizer. The settings shown below were chosen so that the individual time particles would vertically drop and then bounce back up when they ran into the bottom of the canvas.

The number of time particles used in an animation is determined by the Max Stroke parameter in the Path Start control panel. All of the normal Path Start controls are used for the first frame of the animation, and will determine the initial start points of the individual paint strokes and hence the time particles themselves. All of the Path Start settings are ignored in subsequent frames of the animation. 

A common editing mistake is to turn on time particles wihtout setting a reasonable value for the Max Strokes parameter setting.  Many Studio Artist factory presets default with a max strokes setting of 40000. This is done so that when the action button is pressed the paint synthesizer will continue to draw for an indefinite time until a user manually stops action painting by pressing the space bar. 40000 time particles is an exceedingly large number of particles and each frame in an animation with this many particles would take a long time to render. 40 to 400 time particles are probably more reasonable numbers for a typical time particle paint animation. So remember to edit the Max Stroke parameter in the Path Start control panel with an appropriate # of particles before you build a PASeq or start an animation with time particles.

The screen snap below shows the 2 step PASeq used to create the motion-drops1 example.

The first action step used in the PASeq was created using the Geodesic Recursive Growth Image Operation. This action step processes the canvas with the feathering effect created by this particular Ip Op. The second action step is the AutoPaint paint synthesizer step that paints with the time particles. Note that the canvas background is not erased as the animation progresses, so each new output frame is created by painting on top of a feathered version of the previous output frame. 

Real Time Preview and Live Performance Using Time Particles

You can perform live parameter edits while the Studio Artist 4 paint synthesizer is running. This means that you have the ability to preview time particle behavior in real time and make editing changes while the time particles are moving. This can be a great aid to understanding how the individual time particle parameters control the particle movement over time.

Time Particles could also be used as an element of a live visual performance. Live performance could mean a live visual display projected to a live audience or an interactive visual performance streamed into a quicktime movie for later display. The later allows you to interactively work with presets that may render slightly out of real time but end up with a final rendered movie that plays at the speed you want for your final visual presentation or performance.

The key to time particle preview or to live visual performance using time particles is to use Loop Action. Loop Action is a new feature in Studio Artist 4. It allows you to seamlessly loop any individual action. To start Loop Action, just run the Action : Run Loop Action menu command.

Once you have a paint preset that uses time particles running in loop action, you will be able to see the time particle animation proceed in real time as the action loops over and over again. You can then edit the individual time particle parameter controls (or any other paint synthesizer editable parameters) and observe how they influence the time particle movements and overall paint effects respectively.

Live Pen Tracking

Pen Track is a new parameter available in the Time Particle control panel. When turned on, the time particles will be attracted to the current pen position when the pen is in proximity. This is a useful way to interactively control and influence time particle positioning and behavior in a progressing animation.

Pen Track works well when combined with particle Swarming. When Swarming is turned on there are additional parameters available that let you specify how individual particles attract or repulse. Think of the movement of individual birds or insects in an overall swarm and you’ll have an intuitive feel for the behavior of a swarm of particles. 

Just like in nature, a few simple rules to define the behavior of individual objects in a swarm can lead to highly complex movement effects over time. For example, Close Repulsion in a swarm can keep individual particles from getting too close to each other while they are attracted to the pen with Pen Track on. This can lead to chaotic circling movement where the individual particles swarm around the current pen position. Lifting the pen out of proximity can cause the particles to then fly apart until the pen is again brought into proximity, at which point the particles will again move towards the current pen position.

The link below shows off an example of live visual performance using time particles. By working with the pen and pen proximity as loop action animation was progressing i was able to interactively influence and somewhat control the movement of the individual time particles. Because of the interaction of the swarming and border bounce parameters each particle also has a mind of it’s own in the loop action animation.

time particle live performance example

The live interactive performance was spooled into an open movie stream while loop action was progressing. I setup the movie stream frame write menu options to turn on ‘Enable Write on Op End’. For a single preset that is running in loop action this means that whenever the action ends in one cycle of the loop a frame is written out into the open movie stream. If you are running multiple actions recorded as individual steps in a PASeq as a loop action, then you could use the ‘Enable Write on PASeq Cycle’ menu check option so that a single frame would be written out into the open movie stream every time the PASeq completed one cycle in the loop action.  

When i wanted to end the animation i just pressed the space bar to stop loop action. I then closed the open movie stream and had a finished movie file of the time particle animation.

Fracturing a Source Image

Time Particles can reference their original start point locations as they move in an animation. This can be used to create animation effects that fracture an image apart (or vice versa). The way to do this is to use the Time Particle Start Point Tracking option in the Paint Source Offset control panel. A simple example of this kind of effect is shown below.

fractured source image animation example

The Paint Source Offset controls in the paint synthesizer modulate the mapping between the spatial location of a paint stroke and the spatial reference for that canvas location in the source image. The Time Particle Start Point Tracking option means that no matter where a time particle moves in the canvas it will always reference it’s first frame source location.

To pass through the source image with no additional processing when painting, the following Paint Fill Setup parameters were used.

A Rectangular Grid Path Start Generator was used, so the first frame’s time particles were positioned on a grid spaced to fully cover the canvas. In subsequent frames they move based on the time path created by the Time Particle parameters in the paint synthesizer. A Polar Path Angle was chosen for the time particle movement to move the time particle paint nibs away from the center towards the edges of the canvas over time.

Movie Brush Time Particles

A source movie brush can be used with time particle settings turned on. The source movie brush can either be configured to generate photo mosaic style imagery or to encode N smaller movie files that playback as the time particles animate over time. So time particles can be moving in an animation while the movie associated with each time particle is animating it’s playback with the brush nib as well.

This first example was created with a graffiti movie brush. The source movie brush settings were configured to create a photo mosaic effect. The animation was created by processing a movie file loaded in the source palette with a time particle paint synthesizer preset that used a different graffiti source movie brush to create the moving photo mosaic.

graffiti movie brush moving photo mosaic effect

This second example shows of movie source brush time particles that are configured so that different movie files play back in the time particles themselves. You could also process another loaded source movie file with this kind of effect like in the last example if you wanted to make a moving movie mosaic. However, in this example we just see the movement of the time particles as they play back individual movies within their circular paint nibs.

time particles playing back multiple movie files

Self-Animating Bezier Paths as Time Particles

The paint synthesizer has the ability to encapsulate a set of bezier paths in it’s internal bezier path memory located in the Path Shape control panel. Version 4 has a new feature that enables you to use the individual bezier paths as key frames in an animation. When used with time particles this give the time particles the ability to self animate their shape over time in an animation.

A simple example of this is shown below.

self animating bezier path example

A series of bezier paths were hand drawn to define keyframes for an undulating jellyfish. This hand drawn bezier path frame was then recored in the paint synthesizer’s internal bezier path frame memory. The Path Shape settings used to do this kind of embedded bezier path shape animation are shown below.

Each Studio Artist layer has an associated bezier path frame. The bezier path frame is a buffer for bezier vector paths.  Studio Artist has a unique internal graphics model for paint strokes that paints raster paint over vector paths.  The nice thing about vector paths is that they are resolution independent and in the case of bezier paths smoothly editable via control handles when in Bezier Edit operation mode.

Path Generation and Editing via the Path menus

There are a large number of different path generation and editing menu commands located in the main Path menu. The screen snap above shows the result of running the Generate Paths : from Source Edges menu command. The Generate Path commands provide different ways to automatically generate sets of bezier paths from the source or canvas images.

The Path Layer Commands provide different ways to automatically modify the existing bezier path layer.

Path Generation and Editing in Bezier Operation Mode

You can use the popup at the top of the Editor Palette to switch between manual drawing or editing of bezier paths in the current layer’s bezier path frame. Normally the bezier path frame is hidden from view. When in Bezier operation mode the current bezier path frame is displayed on top of the current layer in the main canvas.

Path Layer Record Options

Bezier paths can be generated automatically from your manually drawn paint strokes. Or from auto-drawn paint strokes created by the synthesizer actions. Or from the output of the Vectorizer.  You just need to turn on the appropriate check menus in Path : Path Layer Record Options as shown above.  

Things to do with Bezier Paths

Bezier paths can be used in many different ways in Studio Artist. You could run the Path : Paint Paths : Full Layer menu command to paint the bezier paths with the current Paint Synthesizer paint preset.

A complete set of bezier paths can also be encapsulated in a paint synthesizer preset using it’s internal bezier path memory.

There are different uses for this. One is to provide a way to keyframe interpolate between different sets of bezier paths in a single paint action step to build up fluid paint animation in a Paint Action Sequence.  

encapsulated bezier keyframe paint animation example

Another is to use the bezier paths as a hatching texture while interactively drawing.

This is done by recording the bezier path frame into the paint synthesizer internal bezier path memory and then using that as the path shape in autodraw interactive pen mode.

Or the paint synthesizer can use the individual bezier paths as internal keyframes that are interpolated over time in an animation or while drawing.  

bezier path shape interpolation example

When used with the region Fill as Brush pen mode this provides a way to generate a dynamic brush shape from the interpolating animation of the individual bezier paths.

bezier brush shape interpolation example

The movement of bezier paths over time can be used to specify warps or morphs or spatially varient filtering. This is done using PAseq Context action steps.

bezier morph example

For more information

Here’s a tip on encapsulated bezier keyframe animation derived from hand drawn sketches.

Here’s a tip on automating encapsulated bezier animation.

Here’s a tip on PASeq Contexts.

Here’s a tip on generating a morph animation.