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.
The configuration of the canvas module with name NAME
is located in the canvas/NAME
subdirectory.
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.
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:
The file instream
contains the name of the stream to
read for this input.
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>
.
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>
.
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>
.
The file outstream
contains the name of the stream to
send the frames to.