This is a list of all pdp objects and abstractions with a minimal description.
Take a look at the patches in the doc/ directory for more info. 
(Messy doc & test patches can be found in the test/ directory.)

general purpose pdp modules:

pdp_del		a packet delay line
pdp_reg		a packet register
pdp_snap	takes a snapshot of a packet stream
pdp_trigger	sends out a bang message when a packet is recieved
pdp_route	routes a packet to a specific outlet

image inputs/outputs:

pdp_xv		displays images using the xvideo extension
pdp_v4l		reads images from a video4linux device
pdp_qt		reads quicktime movies

image processors:

pdp_add		adds two images
pdp_bq		spatial biquad filter
pdp_bqt		temporal biquad filter
pdp_constant	fills an image with a constant
pdp_conv	horizontal/vertical seperable convolution filter
pdp_cheby	chebyshev color shaper
pdp_chrot	rotates the chroma components
pdp_gradient	converts a greyscale image using a colour palette
pdp_grey	converts an image to greyscale
pdp_grey2mask	converts a greyscale image to an image mask
pdp_mul		multiplies two images
pdp_affine	shifts and scales a colour plane
pdp_mix		crossfade between 2 images
pdp_mix2	mixes 2 images after applying a gain to each of them
pdp_randmix	crossfades 2 images by taking random pixels
pdp_noise	a noise generator
pdp_rotate	tiled rotate
pdp_scope~	a very simple oscilloscope
pdp_scale	rescale an image
pdp_scan~	phase input scanned synthesis oscillator
pdp_scanxy~	x,y coordinate input scanned synthesis oscillator
pdp_zoom	tiled zoom
pdp_zrot	tiled zoom + rotate

utility abstractions

pdp_pps			computes the packet rate in packets/sec

image abstractions:

pdp_blur		blurs an image
pdp_blur_hor		horizontal blur
pdp_blur_ver		vertical blur
pdp_phase		applies an allpass filter to an image
pdp_phase_hor		horizontal allpass
pdp_phase_ver		vertical allpass
pdp_motion_blur		blurs motion
pdp_motion_phase	phase shifts motion
pdp_alledge		an all edge detector
pdp_conv_emboss		emboss
pdp_conv_sobel_hor	horizontal sobel edge detector
pdp_conv_sobel_ver	vertical sobel edge detector
pdp_conv_sobel_edge	sum of squares of hor and ver
pdp_saturation		change colour saturation
pdp_invert		inverse video

cellular automata (separate lib):

pdp_ca		computes a cellular automaton (as a generator or a filter)
pdp_ca2image	converts a CA packet to a greyscale image
pdp_image2ca	converts an image to a CA packet (black and white)

