List of nodes

Despite being Python classes, nodes follow a consistent logic are documented separately from the rest of the API. Below is a list of nodes included in the PixelPipes core.

Core nodes

operation pixelpipes.graph.Constant(value)

Generates a constant in the pipeline

value [any]:

operation pixelpipes.graph.Debug(source, prefix)

Debug operation enables low-level terminal output of the content that is provided to it. The token content will usually not be printed entierly, only its shape, the value will only be displayed for simple scalar types as well as strings.

Note that tese nodes will be passed to the pipeline only if the compiler is configered with debug flag, otherwise they will be stripped from the graph.

source [Token [None]]: Result of which node to print

prefix [str = ]: String that is prepended to the output

operation pixelpipes.graph.Output(output, label)

Output node that accepts a single input, enables outputting tokens from the final pipeline. Tokens are returned as a tuple, their order is determined by the order of adding output nodes to the graph. Additionally you may also label outputs with non-unique lables that can be used to resolve outputs.

output [Token [None]]: Output token

label [str = default]: Nonunique label of the output

operation pixelpipes.graph.RandomSeed

Returns a pseudo-random number, useful for initializing pseudo-random operations. The seed itself is sampled from a pseudo-random generator that produces the same sequence of seeds for a specific position in the data sequence. This is the corner-stone of repeatability of the pipeline.

operation pixelpipes.graph.ReadFile(filename)

Read file from disk to memory buffer. File is read in binary mode.

filename [Token [char, None]]: Path to the image file

operation pixelpipes.graph.SampleIndex

Returns current sample index. This information can be used instead of random seed to initialize random generators where sequential consistentcy is required.

node pixelpipes.compiler.Variable(name, default)

Variable placeholder that can be overriden later

name [str]:

default []:

Scalar operations

operation pixelpipes.numbers.Add(a, b)

a [Token [float]]: First operand

b [Token [float]]: Second operand

operation pixelpipes.numbers.Ceil(source)

Ceil number and convert to integer.

source [Token [float]]: Number on which ceil operation is performed

operation pixelpipes.numbers.Divide(a, b)

a [Token [float]]: First operand

b [Token [float]]: Second operand

operation pixelpipes.numbers.Equal(a, b)

a [Token [float]]: First operand

b [Token [float]]: Second operand

operation pixelpipes.numbers.Floor(source)

Floor number and convert to integer.

source [Token [float]]: Number to be rounded

operation pixelpipes.numbers.Greater(a, b)

a [Token [float]]: First operand

b [Token [float]]: Second operand

operation pixelpipes.numbers.GreaterEqual(a, b)

a [Token [float]]: First operand

b [Token [float]]: Second operand

operation pixelpipes.numbers.Lower(a, b)

a [Token [float]]: First operand

b [Token [float]]: Second operand

operation pixelpipes.numbers.LowerEqual(a, b)

a [Token [float]]: First operand

b [Token [float]]: Second operand

operation pixelpipes.numbers.Maximum(a, b)

a [Token [float]]: First operand

b [Token [float]]: Second operand

operation pixelpipes.numbers.Minimum(a, b)

a [Token [float]]: First operand

b [Token [float]]: Second operand

operation pixelpipes.numbers.Modulo(a, b)

a [Token [int]]:

b [Token [int]]:

operation pixelpipes.numbers.Multiply(a, b)

a [Token [float]]: First operand

b [Token [float]]: Second operand

operation pixelpipes.numbers.NotEqual(a, b)

a [Token [float]]: First operand

b [Token [float]]: Second operand

operation pixelpipes.numbers.Power(a, b)

a [Token [float]]: First operand

b [Token [float]]: Second operand

macro pixelpipes.numbers.RandomBoolean(seed)

Samples a boolean value with equal probability

seed [Token [int] = @[random]]:

operation pixelpipes.numbers.Round(source)

Round number to closest integer and convert to integer type.

source [Token [float]]: Number to be rounded

operation pixelpipes.numbers.SampleNormal(mean, sigma, seed)

Samples values between from normal distribution.

mean [Token [float] = 0]: Mean value of normal distribution

sigma [Token [float] = 1]: Standard deviation

seed [Token [int] = @[random]]:

operation pixelpipes.numbers.SampleUnform(min, max, seed)

Samples random value between min and max value.

min [Token [float]]: Minimun value

max [Token [float]]: Maximum value

seed [Token [int] = @[random]]:

operation pixelpipes.numbers.Subtract(a, b)

a [Token [float]]: First operand

b [Token [float]]: Second operand

operation pixelpipes.numbers.TensorAdd(a, b, saturate)

a [Token [None]]: First operand

b [Token [None]]: Second operand

saturate [bool = False]: Saturate cast

operation pixelpipes.numbers.TensorDivide(a, b, saturate)

Divides image with another image or scalar (per-element multiplication).

a [Token [None]]: First operand

b [Token [None]]: Second operand

saturate [bool = False]: Saturate cast

operation pixelpipes.numbers.TensorMultiply(a, b, saturate)

Multiplies image with another image or scalar (per-element multiplication).

a [Token [None]]: First operand

b [Token [None]]: Second operand

saturate [bool = False]: Saturate cast

operation pixelpipes.numbers.TensorSubtract(a, b, saturate)

Subtracts two images with same size and number of channels or an image and a number.

a [Token [None]]: First operand

b [Token [None]]: Second operand

saturate [bool = False]: Saturate cast

macro pixelpipes.expression.Expression(source, variables)

Numeric expression with variables

Macro that expands into an arithmetic expression parsed from an input string.

Inputs:

• source: text representation of arithmetic expression

• variables: a map of inputs that are inserted into the expression

Category: arithmetic, macro

source [str]:

variables []:

Flow control

operation pixelpipes.flow.Conditional(true, false, condition)

Node that executes conditional selection, output of branch “true” will be selected if the “condition” is not zero, otherwise output of branch “false” will be selected. Note that the inferred type of these two branches should match as much as possible, otherwise the inferred type of this node will cause problems with dependent nodes.

true [Token [None]]: Use this data if condition is true

false [Token [None]]: Use this data if condition is false

condition [Token [int]]: Condition to test

macro pixelpipes.flow.Switch(inputs, weights, seed)

Random switch between multiple branches, a macro that generates a tree of binary choices based on a random variable. The probability of choosing a defined branch

inputs []: Two or more input branches

weights []: Corresponing branch weights

seed [Token [int] = @[random]]:

Lists

operation pixelpipes.list.CompareEqual(a, b)

a [Token [float, None]]:

b [Token [float, None]]:

operation pixelpipes.list.CompareGreater(a, b)

a [Token [float, None]]:

b [Token [float, None]]:

operation pixelpipes.list.CompareGreaterEqual(a, b)

a [Token [float, None]]:

b [Token [float, None]]:

operation pixelpipes.list.CompareLower(a, b)

a [Token [float, None]]:

b [Token [float, None]]:

operation pixelpipes.list.CompareLowerEqual(a, b)

a [Token [float, None]]:

b [Token [float, None]]:

operation pixelpipes.list.CompareNotEqual(a, b)

a [Token [float, None]]:

b [Token [float, None]]:

operation pixelpipes.list.Concatenate(inputs)

inputs []: Two or more input lists

operation pixelpipes.list.FileList(list)

String list of file patchs. Use this operation to inject file dependencies into the pipeline.

list []:

operation pixelpipes.list.FilterSelect(parent, filter)

Generate a sublist based on values from a filter list

parent [Token [None]]:

filter [Token [int, None]]:

operation pixelpipes.list.GetElement(parent, index)

Returns an element from a list for a given index

parent [Token [None]]:

index [Token [int]]:

macro pixelpipes.list.GetRandom(source, seed)

source [Token [None]]:

seed [Token [int] = @[random]]:

operation pixelpipes.list.Length(parent)

Returns a list length

parent [Token [None]]:

operation pixelpipes.list.ListAsTable(parent, row)

Transform list to table

parent [Token [None, None]]: Source list

row [Token [int]]: Row size, total length of list must be its multiple

operation pixelpipes.list.LogicalAnd(a, b)

a [Token [bool, None]]:

b [Token [bool, None]]:

operation pixelpipes.list.LogicalNot(a)

a [Token [bool, None]]:

operation pixelpipes.list.LogicalOr(a, b)

a [Token [bool, None]]:

b [Token [bool, None]]:

operation pixelpipes.list.MakeList(inputs)

Builds list from inputs. All inputs should be of the same type as the first input, it determines the type of a list.

inputs []:

operation pixelpipes.list.Modulo(a, b)

a [Token [int, None]]:

b [Token [int, None]]:

operation pixelpipes.list.Permutation(length, seed)

Generates a list of numbers from 0 to length in random order.

length [Token [int]]:

seed [Token [int] = @[random]]:

operation pixelpipes.list.Permute(source, seed)

Randomly permutes an input list

source [Token [None]]: Input list

seed [Token [int] = @[random]]:

operation pixelpipes.list.Range(start, end, length, round)

Generates a list of numbers from start to end of a given length

start [Token [float]]:

end [Token [float]]:

length [Token [int]]:

round [Token [bool] = False]:

operation pixelpipes.list.Remap(source, indices)

Maps elements from source list to a result list using indices from indices list.

source [Token [None]]:

indices [Token [int, None]]:

operation pixelpipes.list.Repeat(source, length)

Repeat list element a number of times

source [Token [None]]: Element to repeat

length [Token [int]]: Number of repetitions

operation pixelpipes.list.SublistSelect(parent, begin, end)

Selects a range from the source list as a new list.

parent [Token [None]]: Source list

begin [Token [int]]: Start index

end [Token [int]]: End index

macro pixelpipes.list.Table(source)

Constant Table

Inputs:

• source: Table type

Category: list

source []:

Geometery

Images

Resources

macro pixelpipes.resource.AppendField(source, name, value)

Produce a resource from an input resource and another field. Essentially just node renaming.

source [Resource ()]: Original resource

name [str]: Name of new field

value [Token [None]]: Value for new field

macro pixelpipes.resource.ConditionalResource(true, false, condition)

Node that executes conditional selection, output of branch “true” will be selected if the “condition” is not zero, otherwise output of branch “false” will be selected.

true [Resource ()]: Use this data if condition is true

false [Resource ()]: Use this data if condition is false

condition [Token [int]]: Condition to test

macro pixelpipes.resource.GetField(source, element)

This macro exposes only selected field of an input structure as an output, enabling processing of that data.

source [Resource ()]: Input resource

element [str]: Name of the structure field

macro pixelpipes.resource.MakeResource(inputs)

Macro that generates a resource from given inputs

inputs [ = {}]: A map of inputs that are inserted into the expression

macro pixelpipes.resource.list.GetLastResource(resources)

resources [Resource (__list_length)]:

macro pixelpipes.resource.list.GetResource(resources, index)

resources [Resource (__list_length)]:

index [Token [int]]:

macro pixelpipes.resource.list.GetResourceListLength(resources)

resources [Resource (__list_length)]:

macro pixelpipes.resource.list.ListInterval(resources, begin, end)

resources [Resource (__list_length)]:

begin [Token [int]]:

end [Token [int]]:

macro pixelpipes.resource.list.PermuteResourceSegments(resources, seed)

resources [Resource (__list_length, __list_seg_begin, __list_seg_end)]:

seed [Token [int] = @[random]]:

macro pixelpipes.resource.list.PermuteResources(resources)

Randomly permutes the resource list

resources [Resource (__list_length)]:

macro pixelpipes.resource.list.RandomResource(resources, seed)

Select a random resource from an input list of resources

resources [Resource (__list_length)]:

seed [Token [int] = @[random]]:

macro pixelpipes.resource.list.RandomResourceSegment(resources, seed)

resources [Resource (__list_length, __list_seg_begin, __list_seg_end)]:

seed [Token [int] = @[random]]:

macro pixelpipes.resource.list.RepeatResource(resource, length)

Returns a list of resources where an input resource is repeated a number of times

resource [Resource ()]: Resource to repeat

length [Token [int]]: Number of repetitions

macro pixelpipes.resource.list.ResourceSegment(resources, index)

resources [Resource (__list_length, __list_seg_begin, __list_seg_end)]:

index [Token [int]]:

macro pixelpipes.resource.list.SegmentCount(resources)

resources [Resource (__list_length, __list_seg_begin, __list_seg_end)]: