Class FilterGraph

Represents a filter graph that contains a collection of connected filters.

Inheritance

object

FilterGraph

Implements

ILoggingContext

IDisposable

IAVPointer<_AVFilterGraph>

Inherited Members

object.GetType()

object.ToString()

object.Equals(object)

object.Equals(object, object)

object.ReferenceEquals(object, object)

object.GetHashCode()

Namespace: FFmpeg.Filters

Assembly: FFmpeg.dll

Syntax

public sealed class FilterGraph : ILoggingContext, IDisposable, IAVPointer<_AVFilterGraph>

Remarks

A FilterGraph owns the FilterContext instances created within it and manages the links between them. Once configured, the graph can be used to process audio or video frames.

Properties

View Source

Count

Gets the number of filters contained in the graph.

Declaration

public int Count { get; }

Property Value

Type	Description
int

View Source

Filters

Gets a read-only list view over all filters contained in the graph.

Declaration

public IReadOnlyList<FilterContext> Filters { get; }

Property Value

Type	Description
IReadOnlyList<FilterContext>

View Source

InputFilters

Gets all buffer source filters contained in the graph.

Declaration

public IEnumerable<FilterContext> InputFilters { get; }

Property Value

Type	Description
IEnumerable<FilterContext>

Remarks

These are the filters that provide input frames to the graph.

View Source

this[int]

Gets the filter at the specified index.

Declaration

public FilterContext this[int index] { get; }

Parameters

Type	Name	Description
int	index	The zero-based index of the filter.

Property Value

Type	Description
FilterContext	The FilterContext at the specified index.

Exceptions

Type	Condition
ArgumentOutOfRangeException	`index` is outside the bounds of the graph.

View Source

OutputFilters

Gets all buffer sink filters contained in the graph.

Declaration

public IEnumerable<FilterContext> OutputFilters { get; }

Property Value

Type	Description
IEnumerable<FilterContext>

Remarks

These are the filters that receive processed output frames from the graph.

View Source

SinkFilters

Gets all sink filters contained in the graph.

Declaration

public IEnumerable<FilterContext> SinkFilters { get; }

Property Value

Type	Description
IEnumerable<FilterContext>

Remarks

Sink filters have no output pads and consume media from the graph.

View Source

SourceFilters

Gets all source filters contained in the graph.

Declaration

public IEnumerable<FilterContext> SourceFilters { get; }

Property Value

Type	Description
IEnumerable<FilterContext>

Remarks

Source filters have no input pads and generate media for the graph.

View Source

Threads

Gets or sets the maximum number of threads used when processing the filter graph.

Declaration

public int Threads { get; set; }

Property Value

Type	Description
int

Remarks

A value of 0 allows FFmpeg to choose an appropriate number of threads.

View Source

UnlinkedInFilters

Gets all filters that have at least one unconnected input pad.

Declaration

public IEnumerable<FilterContext> UnlinkedInFilters { get; }

Property Value

Type	Description
IEnumerable<FilterContext>

View Source

UnlinkedOutFilters

Gets all filters that have at least one unconnected output pad.

Declaration

public IEnumerable<FilterContext> UnlinkedOutFilters { get; }

Property Value

Type	Description
IEnumerable<FilterContext>

Methods

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Allocate()

Allocates a new, empty filter graph.

Declaration

public static FilterGraph Allocate()

Returns

Type	Description
FilterGraph	A new unconfigured FilterGraph instance.

Remarks

Unlike the Create methods, this method only allocates the filter graph. No filters are created or parsed.

Exceptions

Type	Condition
OutOfMemoryException	FFmpeg was unable to allocate the filter graph.

View Source

Config()

Validates and configures all links in the filter graph.

Declaration

public AVResult32 Config()

Returns

Type	Description
AVResult32	The result of the configuration operation.

Remarks

This method should be called after all filters have been created and linked, and before frames are processed through the graph.

View Source

Copy()

Creates a unconfigured copy of the filter graph.

Declaration

public FilterGraph Copy()

Returns

Type	Description
FilterGraph	A new FilterGraph containing equivalent filters and connections.

Remarks

The copied graph contains newly allocated filter contexts configured with the same options and topology as the original graph. There is not ffmpeg function. This function tries to recreate the filter graph with the same paramters. Buffer sinks and filter contexts named auto_* are not configured.

View Source

Create(out FilterInOutList?, string, out FilterInOutList?)

Creates a filter graph from the specified filter graph description.

Declaration

public static FilterGraph Create(out FilterInOutList? inputs, string filter, out FilterInOutList? outputs)

Parameters

Type	Name	Description
FilterInOutList	inputs	When this method returns, contains any unlinked input endpoints remaining after parsing.
string	filter	The FFmpeg filter graph description to parse.
FilterInOutList	outputs	When this method returns, contains any unlinked output endpoints remaining after parsing.

Returns

Type	Description
FilterGraph	The newly created FilterGraph.

Remarks

This overload preserves any unlinked input and output endpoints returned by FFmpeg, allowing them to be connected later.

Exceptions

Type	Condition
FFmpegException	Thrown if the filter graph could not be parsed.

View Source

Create(string)

Creates a filter graph from the specified filter graph description.

Declaration

public static FilterGraph Create(string filter)

Parameters

Type	Name	Description
string	filter	The FFmpeg filter graph description to parse.

Returns

Type	Description
FilterGraph	The newly created and parsed FilterGraph.

Remarks

This method parses the supplied filter graph description using avfilter_graph_parse_ptr(). Any unlinked inputs or outputs are discarded. Use Create(out FilterInOutList?, string, out FilterInOutList?) if access to unlinked endpoints is required.

Exceptions

Type	Condition
FFmpegException	Thrown if the filter graph could not be parsed.

View Source

Dispose()

Releases all resources used by this FilterGraph instance.

Declaration

public void Dispose()

View Source

Dump()

Returns a textual representation of the current filter graph.

Declaration

public string Dump()

Returns

Type	Description
string	A human-readable description of the graph.

Remarks

This method is primarily intended for debugging and diagnostics.

View Source

~FilterGraph()

Finalizer for the FilterGraph class.

Declaration

protected ~FilterGraph()

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FindFilter(string)

Finds a filter by its instance name.

Declaration

public FilterContext? FindFilter(string name)

Parameters

Type	Name	Description
string	name	The name of the filter instance.

Returns

Type	Description
FilterContext	The matching filter, or null if no filter with the specified name exists.

View Source

Flush()

Creates a copy of the filter graph and disposed the old one.

Declaration

public void Flush()

View Source

GetEnumerator()

Returns an enumerator that iterates through the filters in the graph.

Declaration

public IEnumerator<FilterContext> GetEnumerator()

Returns

Type	Description
IEnumerator<FilterContext>	An enumerator over the graph's filters.

View Source

Insert(FilterLink, FilterContext, int, int)

Inserts a filter into an existing link between two filters.

Declaration

public AVResult32 Insert(FilterLink link, FilterContext filter, int srcFilterPad, int destFilterPad)

Parameters

Type	Name	Description
FilterLink	link	The link to split.
FilterContext	filter	The filter to insert.
int	srcFilterPad	The output pad index on the inserted filter.
int	destFilterPad	The input pad index on the inserted filter.

Returns

Type	Description
AVResult32	The result of the insertion operation.

View Source

Link(FilterContext, FilterContext)

Connects the first output pad of one filter to the first input pad of another filter.

Declaration

public AVResult32 Link(FilterContext src, FilterContext dst)

Parameters

Type	Name	Description
FilterContext	src	The source filter.
FilterContext	dst	The destination filter.

Returns

Type	Description
AVResult32	The result of the link operation.

View Source

Link(FilterContext, int, FilterContext, int)

Connects an output pad of one filter to an input pad of another filter.

Declaration

public AVResult32 Link(FilterContext src, int srcpad, FilterContext dst, int dstpad)

Parameters

Type	Name	Description
FilterContext	src	The source filter.
int	srcpad	The zero-based output pad index on `src`.
FilterContext	dst	The destination filter.
int	dstpad	The zero-based input pad index on `dst`.

Returns

Type	Description
AVResult32	The result of the link operation.

View Source

Parse(out FilterInOutList, string, out FilterInOutList)

Parses a filter graph description without linking it to existing filters.

Declaration

public AVResult32 Parse(out FilterInOutList inputs, string filters, out FilterInOutList outputs)

Parameters

Type	Name	Description
FilterInOutList	inputs	When this method returns, contains the unconnected input filters.
string	filters	The filter graph description.
FilterInOutList	outputs	When this method returns, contains the unconnected output filters.

Returns

Type	Description
AVResult32	The result of the parse operation.

Remarks

This method wraps FFmpeg's avfilter_graph_parse2().

View Source

ParseAndLink(FilterInOutList?, string, FilterInOutList?)

Parses a filter graph description and connects it to the specified input and output filters.

Declaration

public AVResult32 ParseAndLink(FilterInOutList? input, string filters, FilterInOutList? output)

Parameters

Type	Name	Description
FilterInOutList	input	The input filter list, or null if no explicit input list should be supplied.
string	filters	The filter graph description.
FilterInOutList	output	The output filter list, or null if no explicit output list should be supplied.

Returns

Type	Description
AVResult32	The result of the parse operation.

Remarks

This method wraps FFmpeg's avfilter_graph_parse_ptr(). Any unconnected inputs or outputs remaining after parsing are written back into the supplied FilterInOutList instances.

View Source

ParseAndLink(out FilterInOutList, string, out FilterInOutList)

Parses a filter graph description and returns any unconnected inputs and outputs.

Declaration

public AVResult32 ParseAndLink(out FilterInOutList input, string filters, out FilterInOutList output)

Parameters

Type	Name	Description
FilterInOutList	input	When this method returns, contains the unconnected input filters.
string	filters	The filter graph description.
FilterInOutList	output	When this method returns, contains the unconnected output filters.

Returns

Type	Description
AVResult32	The result of the parse operation.

Remarks

This method wraps FFmpeg's avfilter_graph_parse_ptr().

View Source

TryCreate(out FilterInOutList?, string, out FilterInOutList?, out FilterGraph?)

Attempts to create a FilterGraph by parsing the specified FFmpeg filter graph description.

Declaration

public static AVResult32 TryCreate(out FilterInOutList? inputs, string filter, out FilterInOutList? outputs, out FilterGraph? filterGraph)

Parameters

Type	Name	Description
FilterInOutList	inputs	When this method returns successfully, contains the collection of unlinked input endpoints remaining after parsing the filter graph; otherwise, null.
string	filter	The FFmpeg filter graph description to parse.
FilterInOutList	outputs	When this method returns successfully, contains the collection of unlinked output endpoints remaining after parsing the filter graph; otherwise, null.
FilterGraph	filterGraph	When this method returns successfully, contains the newly created FilterGraph; otherwise, null.

Returns

Type	Description
AVResult32	`0` if the filter graph was successfully created and parsed; otherwise, a negative FFmpeg error code.

Remarks

This method allocates a new FilterGraph and parses the specified filter graph description using FFmpeg. Any filter endpoints that are not connected during parsing are returned through inputs and outputs so they can be linked manually.

View Source

TryCreate(string, out FilterGraph?)

Attempts to create a filter graph from the specified filter graph description.

Declaration

public static AVResult32 TryCreate(string filter, out FilterGraph? graph)

Parameters

Type	Name	Description
string	filter	The FFmpeg filter graph description to parse.
FilterGraph	graph	When this method returns successfully, contains the created FilterGraph; otherwise, null.

Returns

Type	Description
AVResult32	The result of the parse operation.

Remarks

This overload parses the graph description but discards any unlinked input or output endpoints. Use TryCreate(out FilterInOutList?, string, out FilterInOutList?, out FilterGraph?) if access to those endpoints is required.

Implements

ILoggingContext

IDisposable

IAVPointer<T>

Extension Methods

LoggingContextExtensions.Debug(ILoggingContext, string)

LoggingContextExtensions.Error(ILoggingContext, string)

LoggingContextExtensions.Fatal(ILoggingContext, string)

LoggingContextExtensions.Info(ILoggingContext, string)

LoggingContextExtensions.Log(ILoggingContext, LogLevel, string)

LoggingContextExtensions.Panic(ILoggingContext, string)

LoggingContextExtensions.Trace(ILoggingContext, string)

LoggingContextExtensions.Verbose(ILoggingContext, string)

LoggingContextExtensions.Warning(ILoggingContext, string)