Scan CHOP

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Summary

The Scan CHOP converts a SOP or TOP to oscilloscope or laser friendly control waves. The output is usually in the audible range and can be heard directly via an Audio Device Out CHOP, or used to drive the X and Y deflector inputs of an oscilloscope, or a laser projector recreating the imagery. The output can also be visualized through use of a Limit SOP.

A sample component found at: Op to Audio CHOP example

A sample video can be found at: Total Internal Reflection

See also: EtherDream CHOP, EtherDream DAT

PythonIcon.png scanCHOP_Class

Parameters - Scan Page

Source OP - Choose the source node family.

  • TOP - A raster image is converted to control signals by converting each pixel's location to X and Y amplitude values.
  • SOP - A geometry is converted to control signals by converting each point's position to X and Y amplitude values.
  • CHOP - A waveform is converted to control signals by converting each graph into corresponding horizontal and vertical offsets.

Sample Rate - Samples per second, the output sample rate.

Swap Output - Reverse the X and Y channel outputs.

X Scale - Scale the x amplitude.

Y Scale - Scale the y amplitude.

Rotate - Specified in degrees, rotates the output x,y values.

Randomize Samples - Output all samples in a random order. Creates a fuzzy chaotic image on an oscilloscope.

Output Color - If on, r,g,b channels are created.

Red Scale - Scale the output r channel.

Green Scale - Scale the output g channel.

Blue Scale - Scale the output b channel.

Blanking Count - In the case of SOP input, the number of black/off positions to insert between geometry primitives. In the case of TOP input, the number of black/off positions to insert between full raster scans. Color output must be enabled.

Parameters - TOP Page

A raster image is converted to control signals by converting each pixel's location to X and Y amplitude values. The luminance is controlled by how long each sample is "drawn" on the scope. Since the output is low bandwidth, different resampling and ordering options are available for minimizing (or enhancing) flicker.

TOP - Path to the TOP node.

Width - The number of columns to resample the image at.

Height - The number of rows to resample the image at.

Level - The number of brightness levels each pixel can have.

Auto Reduce - Automatically reduce the number of rows and columns dynamically to keep the output frame rate at a constant level.

Layered - Output the pixels in order of brightness, else they are output left to right for each row.

Interleave - Controls the order in which rows are output to minimize flicker.

  • Sweep - The rows are output in order, from top to bottom.
  • Even Odd - The rows are output in two passes, first even, then odd.
  • Max - The rows are output in fully interleaved fashion.

Parameters - SOP Page

Every point in a SOP creates a frame-buffered, stereo audio sample, where the SOP vertex X is placed on the X channel and Y is placed on the Y channel. The oscilloscope output thus contains no aliased lines, just razor-sharp vectors.

SOP - Path to the SOP node.

Vertex Order - Output the points in the same order as the vertices of each polygon, instead of the order in which the points are defined in the geometry.

Limit Step Size - Breakup long x,y jumps into several smaller incremental jumps.

Step Size - The distance each x,y can change when above option enabled.

Vertex Repeat - Repeat each vertex of the each primitive multiple times.

Camera - Project the geometry onto a 2D plane from this camera, otherwise, only the original x,y components of the geometry are used.

Parameters - CHOP Page

A waveform is converted to control signals by converting each graph into corresponding horizontal and vertical offsets, reproducing the original CHOP waveform. The CHOP should not be Time Sliced, but instead have some length (example a Trail CHOP or animated Wave CHOP).

CHOP - Path to the CHOP node.

Trigger - The output graph will begin where its value exceeds this value. This allows for steady 'frozen' waveforms, analagous to an oscilloscope triggered sweep.

Trigger Value - .

Trim - .

Trim Value - .

Standard Options and Local Variables

  • $L - length
  • $S - start
  • $E - end
  • $NC - number of channels

See also Audio Device Out CHOP