Blinker - Canvas

The canvas module allows to merge several streams into one. It works lie a canvas, onto which rectangular sections of different streams are drawn. The result obtained on the canvas is then sent to a single output stream.

Configuration

The configuration of the canvas module with name NAME is located in the canvas/NAME subdirectory.

Format

The file format describes the format of the canvas, i.e. its dimensions, the number of channels and the color depth on each channel. The file must contain a string <width>x<height>-<channels>/<colors>, e.g. 18x8-1/256 for 18 pixels width, 8 pixels height in 256 grayscales.

Input List

The inputs to be drawn onto the canvas are configured in the inputs subdirectory. Each input is configured in an own subdirectory in inputs. E.g. the configurations for inputs with names top and bottom reside in subdirectories inputs/top and inputs/bottom respectively. All inputs are drawn to the canvas in alphanumerical order, i.e. top is painted over bottom on overlapping pixels.

The configuration inside an input subdirectory consists of the following settings:

Input Stream

The file instream contains the name of the stream to read for this input.

Source Position

The file srcpos defines the top-left corner of the recangular section to be taken from the stream. The file must contain a string <x>x<y>.

Size

The file size defines the size of the recangular section to be taken from the stream. The file must contain a string <width>x<height>.

Destination Position

The file destpos defines the top-left corner of the recangular section on the canvas to draw to. The file must contain a string <x>x<y>.

Output Stream

The file outstream contains the name of the stream to send the frames to.