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node-av / lib / FilterContext

Class: FilterContext ​

Defined in: src/lib/filter-context.ts:48

Filter instance in a filter graph.

Represents an instantiated filter within a filter graph. Each context contains a specific filter configuration with its parameters, connections to other filters, and input/output pads. Supports both software and hardware filtering operations. Essential for building complex filter chains for audio/video processing.

Direct mapping to FFmpeg's AVFilterContext.

Example ​

typescript
import { FilterContext, FilterGraph, Filter, FFmpegError } from 'node-av';

// Create filter context in a graph
const graph = new FilterGraph();
const filter = Filter.getByName('scale');
const context = graph.createFilter(filter, 'scaler');

// Initialize with parameters
const ret = context.initStr('640:480');
FFmpegError.throwIfError(ret, 'initStr');

// Link filters together
const ret2 = source.link(0, context, 0);
FFmpegError.throwIfError(ret2, 'link');

// For buffer source/sink
const ret3 = await bufferSrc.buffersrcAddFrame(frame);
FFmpegError.throwIfError(ret3, 'buffersrcAddFrame');

See ​

Extends ​

Implements ​

Constructors ​

Constructor ​

new FilterContext(native): FilterContext

Defined in: src/lib/filter-context.ts:56

Internal

Parameters ​

native ​

NativeFilterContext

The native filter context instance

Returns ​

FilterContext

Overrides ​

OptionMember<NativeFilterContext>.constructor

Properties ​

native ​

protected native: NativeFilterContext

Defined in: src/lib/option.ts:999

Inherited from ​

OptionMember.native

Accessors ​

filter ​

Get Signature ​

get filter(): null | Filter

Defined in: src/lib/filter-context.ts:83

Filter descriptor.

Reference to the filter type this context instantiates.

Direct mapping to AVFilterContext->filter.

Returns ​

null | Filter

graph ​

Get Signature ​

get graph(): null | NativeFilterGraph

Defined in: src/lib/filter-context.ts:95

Parent filter graph.

Reference to the graph containing this filter context.

Direct mapping to AVFilterContext->graph.

Returns ​

null | NativeFilterGraph

hwDeviceCtx ​

Get Signature ​

get hwDeviceCtx(): null | HardwareDeviceContext

Defined in: src/lib/filter-context.ts:141

Hardware device context.

Hardware acceleration context for GPU-based filtering. Set to enable hardware-accelerated filter operations.

Direct mapping to AVFilterContext->hw_device_ctx.

Returns ​

null | HardwareDeviceContext

Set Signature ​

set hwDeviceCtx(value): void

Defined in: src/lib/filter-context.ts:161

Parameters ​
value ​

null | HardwareDeviceContext

Returns ​

void

name ​

Get Signature ​

get name(): null | string

Defined in: src/lib/filter-context.ts:68

Filter instance name.

User-assigned name for this filter instance in the graph. Used for identification and debugging.

Direct mapping to AVFilterContext->name.

Returns ​

null | string

Set Signature ​

set name(value): void

Defined in: src/lib/filter-context.ts:72

Parameters ​
value ​

null | string

Returns ​

void

nbInputs ​

Get Signature ​

get nbInputs(): number

Defined in: src/lib/filter-context.ts:106

Number of input pads.

Total number of input connections this filter can accept.

Direct mapping to AVFilterContext->nb_inputs.

Returns ​

number

nbOutputs ​

Get Signature ​

get nbOutputs(): number

Defined in: src/lib/filter-context.ts:117

Number of output pads.

Total number of output connections this filter can provide.

Direct mapping to AVFilterContext->nb_outputs.

Returns ​

number

ready ​

Get Signature ​

get ready(): number

Defined in: src/lib/filter-context.ts:129

Filter readiness state.

Indicates if the filter is ready for processing. Non-zero when ready.

Direct mapping to AVFilterContext->ready.

Returns ​

number

Methods ​

[dispose]() ​

[dispose](): void

Defined in: src/lib/filter-context.ts:809

Dispose of the filter context.

Implements the Disposable interface for automatic cleanup. Equivalent to calling free().

Returns ​

void

Example ​

typescript
{
  using context = graph.createFilter(filter, 'test');
  context.initStr('640:480');
  // Use context...
} // Automatically freed when leaving scope

Implementation of ​

Disposable.[dispose]

buffersinkGetChannelLayout() ​

buffersinkGetChannelLayout(): ChannelLayout

Defined in: src/lib/filter-context.ts:701

Get channel layout from buffer sink.

Returns the channel layout of audio from a buffer sink filter. Only valid for audio buffer sink filters.

Direct mapping to av_buffersink_get_channel_layout().

Returns ​

ChannelLayout

Channel layout configuration

Example ​

typescript
const layout = bufferSink.buffersinkGetChannelLayout();
console.log(`Channels: ${layout.nbChannels}`);

buffersinkGetFormat() ​

buffersinkGetFormat(): AVPixelFormat | AVSampleFormat

Defined in: src/lib/filter-context.ts:579

Get pixel/sample format from buffer sink.

Returns the format of frames from a buffer sink filter. Only valid for buffer sink filters.

Direct mapping to av_buffersink_get_format().

Returns ​

AVPixelFormat | AVSampleFormat

Pixel format for video, sample format for audio

Example ​

typescript
import { AV_PIX_FMT_YUV420P } from 'node-av/constants';

const format = bufferSink.buffersinkGetFormat();
if (format === AV_PIX_FMT_YUV420P) {
  console.log('Output is YUV420P');
}

buffersinkGetFrame() ​

buffersinkGetFrame(frame): Promise<number>

Defined in: src/lib/filter-context.ts:490

Get a frame from a buffer sink filter.

Retrieves a filtered frame from the filter graph through a buffer sink. Only valid for buffer sink filters.

Direct mapping to av_buffersink_get_frame().

Parameters ​

frame ​

Frame

Frame to receive filtered data

Returns ​

Promise<number>

0 on success, negative AVERROR on error:

  • AVERROR_EAGAIN: No frame available yet
  • AVERROR_EOF: No more frames will be produced
  • AVERROR_EINVAL: Not a buffer sink filter

Example ​

typescript
import { FFmpegError, Frame } from 'node-av';
import { AVERROR_EAGAIN, AVERROR_EOF } from 'node-av/constants';

const frame = new Frame();
frame.alloc();

const ret = await bufferSink.buffersinkGetFrame(frame);
if (ret === AVERROR_EAGAIN) {
  // No frame available yet
} else if (ret === AVERROR_EOF) {
  // End of stream
} else {
  FFmpegError.throwIfError(ret, 'buffersinkGetFrame');
  // Process filtered frame
}

See ​

buffersrcAddFrame To send frames for filtering

buffersinkGetFrameRate() ​

buffersinkGetFrameRate(): Rational

Defined in: src/lib/filter-context.ts:660

Get frame rate from buffer sink.

Returns the frame rate of video from a buffer sink filter. Only valid for video buffer sink filters.

Direct mapping to av_buffersink_get_frame_rate().

Returns ​

Rational

Frame rate as Rational

Example ​

typescript
const frameRate = bufferSink.buffersinkGetFrameRate();
console.log(`Frame rate: ${frameRate.num}/${frameRate.den} fps`);

buffersinkGetFrameSync() ​

buffersinkGetFrameSync(frame): number

Defined in: src/lib/filter-context.ts:534

Get frame from buffer sink filter synchronously. Synchronous version of buffersinkGetFrame.

Retrieves a filtered frame from a buffer sink filter. Only valid for buffer sink filters (buffersink, abuffersink).

Direct mapping to av_buffersink_get_frame().

Parameters ​

frame ​

Frame

Frame to receive filtered data

Returns ​

number

0 on success, negative AVERROR on error:

  • AVERROR_EAGAIN: Need more input
  • AVERROR_EOF: No more frames available
  • AVERROR_EINVAL: Invalid parameters

Example ​

typescript
import { Frame, FFmpegError } from 'node-av';
import { AVERROR_EAGAIN, AVERROR_EOF } from 'node-av/constants';

// Get filtered frame
const filtered = new Frame();
const ret = bufferSink.buffersinkGetFrameSync(filtered);

if (ret === 0) {
  // Process filtered frame
  console.log(`Got filtered frame with ${filtered.nbSamples} samples`);
  filtered.unref();
} else if (ret === AVERROR_EAGAIN) {
  // Need more input frames
} else if (ret === AVERROR_EOF) {
  // No more frames
} else {
  FFmpegError.throwIfError(ret, 'buffersinkGetFrameSync');
}

See ​

buffersinkGetFrame For async version

buffersinkGetHeight() ​

buffersinkGetHeight(): number

Defined in: src/lib/filter-context.ts:619

Get frame height from buffer sink.

Returns the height of video frames from a buffer sink filter. Only valid for video buffer sink filters.

Direct mapping to av_buffersink_get_h().

Returns ​

number

Frame height in pixels

Example ​

typescript
const height = bufferSink.buffersinkGetHeight();
console.log(`Output height: ${height}px`);

buffersinkGetSampleAspectRatio() ​

buffersinkGetSampleAspectRatio(): Rational

Defined in: src/lib/filter-context.ts:639

Get sample aspect ratio from buffer sink.

Returns the pixel aspect ratio of video frames from a buffer sink filter. Only valid for video buffer sink filters.

Direct mapping to av_buffersink_get_sample_aspect_ratio().

Returns ​

Rational

Sample aspect ratio as Rational

Example ​

typescript
const sar = bufferSink.buffersinkGetSampleAspectRatio();
console.log(`SAR: ${sar.num}:${sar.den}`);

buffersinkGetSampleRate() ​

buffersinkGetSampleRate(): number

Defined in: src/lib/filter-context.ts:681

Get sample rate from buffer sink.

Returns the sample rate of audio from a buffer sink filter. Only valid for audio buffer sink filters.

Direct mapping to av_buffersink_get_sample_rate().

Returns ​

number

Sample rate in Hz

Example ​

typescript
const sampleRate = bufferSink.buffersinkGetSampleRate();
console.log(`Sample rate: ${sampleRate} Hz`);

buffersinkGetTimeBase() ​

buffersinkGetTimeBase(): Rational

Defined in: src/lib/filter-context.ts:554

Get time base from buffer sink.

Returns the time base of frames from a buffer sink filter. Only valid for buffer sink filters.

Direct mapping to av_buffersink_get_time_base().

Returns ​

Rational

Time base as Rational

Example ​

typescript
const timeBase = bufferSink.buffersinkGetTimeBase();
console.log(`Time base: ${timeBase.num}/${timeBase.den}`);

buffersinkGetWidth() ​

buffersinkGetWidth(): number

Defined in: src/lib/filter-context.ts:599

Get frame width from buffer sink.

Returns the width of video frames from a buffer sink filter. Only valid for video buffer sink filters.

Direct mapping to av_buffersink_get_w().

Returns ​

number

Frame width in pixels

Example ​

typescript
const width = bufferSink.buffersinkGetWidth();
console.log(`Output width: ${width}px`);

buffersrcAddFrame() ​

buffersrcAddFrame(frame): Promise<number>

Defined in: src/lib/filter-context.ts:323

Add a frame to a buffer source filter.

Sends a frame into the filter graph through a buffer source. Only valid for buffer source filters. Send null to signal EOF.

Direct mapping to av_buffersrc_add_frame().

Parameters ​

frame ​

Frame to send, or null for EOF

null | Frame

Returns ​

Promise<number>

0 on success, negative AVERROR on error:

  • AVERROR_EAGAIN: Filter needs more output consumption
  • AVERROR_EOF: Filter has been closed
  • AVERROR_EINVAL: Not a buffer source filter
  • AVERROR_ENOMEM: Memory allocation failure

Example ​

typescript
import { FFmpegError } from 'node-av';
import { AVERROR_EAGAIN } from 'node-av/constants';

// Send frame to filter graph
const ret = await bufferSrc.buffersrcAddFrame(frame);
if (ret === AVERROR_EAGAIN) {
  // Need to consume output first
} else {
  FFmpegError.throwIfError(ret, 'buffersrcAddFrame');
}

// Signal EOF
await bufferSrc.buffersrcAddFrame(null);

See ​

buffersinkGetFrame To retrieve filtered frames

buffersrcAddFrameSync() ​

buffersrcAddFrameSync(frame): number

Defined in: src/lib/filter-context.ts:365

Add frame to buffer source filter synchronously. Synchronous version of buffersrcAddFrame.

Sends a frame to a buffer source filter for processing. Only valid for buffer source filters (buffer, abuffer).

Direct mapping to av_buffersrc_add_frame().

Parameters ​

frame ​

Frame to send (null to mark EOF)

null | Frame

Returns ​

number

0 on success, negative AVERROR on error:

  • AVERROR_EAGAIN: Need to retrieve output first
  • AVERROR_EOF: Graph has finished processing
  • AVERROR_EINVAL: Invalid parameters
  • AVERROR(ENOMEM): Memory allocation failure

Example ​

typescript
import { FFmpegError } from 'node-av';
import { AVERROR_EAGAIN } from 'node-av/constants';

// Send frame to filter
const ret = bufferSrc.buffersrcAddFrameSync(frame);
if (ret === AVERROR_EAGAIN) {
  // Need to get output frames first
  const filtered = new Frame();
  bufferSink.buffersinkGetFrameSync(filtered);
} else {
  FFmpegError.throwIfError(ret, 'buffersrcAddFrameSync');
}

// Mark end of stream
bufferSrc.buffersrcAddFrameSync(null);

See ​

buffersrcAddFrame For async version

buffersrcParametersSet() ​

buffersrcParametersSet(params): number

Defined in: src/lib/filter-context.ts:434

Set parameters for a buffer source filter.

Configures the format and properties of frames that will be sent to the buffer source. Must be called before sending frames.

Direct mapping to av_buffersrc_parameters_set().

Parameters ​

params ​

Source parameters

channelLayout? ​

bigint

Audio channel layout

colorRange? ​

AVColorRange

Color range for video

colorSpace? ​

AVColorSpace

Color space for video

format? ​

AVPixelFormat | AVSampleFormat

Pixel or sample format

frameRate? ​

IRational

Video frame rate

height? ​

number

Video frame height

hwFramesCtx? ​

null | HardwareFramesContext

Hardware frames context

sampleAspectRatio? ​

IRational

Pixel aspect ratio

sampleRate? ​

number

Audio sample rate

timeBase? ​

IRational

Time base for timestamps

width? ​

number

Video frame width

Returns ​

number

0 on success, negative AVERROR on error:

  • AVERROR_EINVAL: Invalid parameters
  • AVERROR_ENOMEM: Memory allocation failure

Example ​

typescript
import { FFmpegError, Rational } from 'node-av';
import { AV_PIX_FMT_YUV420P } from 'node-av/constants';

// Configure video buffer source
const ret = bufferSrc.buffersrcParametersSet({
  width: 1920,
  height: 1080,
  format: AV_PIX_FMT_YUV420P,
  timeBase: { num: 1, den: 25 },
  frameRate: { num: 25, den: 1 }
});
FFmpegError.throwIfError(ret, 'buffersrcParametersSet');

@example
```typescript
import { FFmpegError } from 'node-av';
import { AV_SAMPLE_FMT_FLTP } from 'node-av/constants';

// Configure audio buffer source
const ret = bufferSrc.buffersrcParametersSet({
  format: AV_SAMPLE_FMT_FLTP,
  sampleRate: 44100,
  channelLayout: AV_CHANNEL_LAYOUT_STEREO
});
FFmpegError.throwIfError(ret, 'buffersrcParametersSet');

free() ​

free(): void

Defined in: src/lib/filter-context.ts:721

Free the filter context.

Releases all resources associated with the filter context. The context becomes invalid after calling this.

Direct mapping to avfilter_free().

Returns ​

void

Example ​

typescript
context.free();
// Context is now invalid

See ​

Symbol.dispose For automatic cleanup

getNative() ​

getNative(): NativeFilterContext

Defined in: src/lib/filter-context.ts:790

Internal

Get the underlying native FilterContext object.

Returns ​

NativeFilterContext

The native FilterContext binding object

Implementation of ​

NativeWrapper.getNative

getOption() ​

Get an option value from this object.

Uses the AVOption API to retrieve options.

Direct mapping to av_opt_get* functions.

Param ​

Option name

Param ​

Option type (defaults to AV_OPT_TYPE_STRING)

Param ​

Search flags (default: AV_OPT_SEARCH_CHILDREN)

Example ​

typescript
import { AV_OPT_TYPE_STRING, AV_OPT_TYPE_RATIONAL, AV_OPT_TYPE_PIXEL_FMT, AV_OPT_TYPE_INT64 } from 'node-av/constants';

// String options (default)
const preset = obj.getOption('preset');
const codec = obj.getOption('codec', AV_OPT_TYPE_STRING);

// Typed options
const framerate = obj.getOption('framerate', AV_OPT_TYPE_RATIONAL); // Returns {num, den}
const pixFmt = obj.getOption('pix_fmt', AV_OPT_TYPE_PIXEL_FMT); // Returns AVPixelFormat
const bitrate = obj.getOption('bitrate', AV_OPT_TYPE_INT64); // Returns bigint

Call Signature ​

getOption(name, type?, searchFlags?): null | string

Defined in: src/lib/option.ts:1217

Parameters ​
name ​

string

type? ​

AVOptionTypeString

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | string

Inherited from ​

OptionMember.getOption

Call Signature ​

getOption(name, type, searchFlags?): null | string

Defined in: src/lib/option.ts:1218

Parameters ​
name ​

string

type ​

AVOptionTypeColor

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | string

Inherited from ​

OptionMember.getOption

Call Signature ​

getOption(name, type, searchFlags?): null | number

Defined in: src/lib/option.ts:1221

Parameters ​
name ​

string

type ​

AVOptionTypeInt

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | number

Inherited from ​

OptionMember.getOption

Call Signature ​

getOption(name, type, searchFlags?): null | bigint

Defined in: src/lib/option.ts:1222

Parameters ​
name ​

string

type ​

AVOptionTypeInt64

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | bigint

Inherited from ​

OptionMember.getOption

Call Signature ​

getOption(name, type, searchFlags?): null | number

Defined in: src/lib/option.ts:1223

Parameters ​
name ​

string

type ​

AVOptionTypeUint

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | number

Inherited from ​

OptionMember.getOption

Call Signature ​

getOption(name, type, searchFlags?): null | bigint

Defined in: src/lib/option.ts:1224

Parameters ​
name ​

string

type ​

AVOptionTypeUint64

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | bigint

Inherited from ​

OptionMember.getOption

Call Signature ​

getOption(name, type, searchFlags?): null | number

Defined in: src/lib/option.ts:1225

Parameters ​
name ​

string

type ​

AVOptionTypeFlags

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | number

Inherited from ​

OptionMember.getOption

Call Signature ​

getOption(name, type, searchFlags?): null | boolean

Defined in: src/lib/option.ts:1226

Parameters ​
name ​

string

type ​

AVOptionTypeBool

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | boolean

Inherited from ​

OptionMember.getOption

Call Signature ​

getOption(name, type, searchFlags?): null | number

Defined in: src/lib/option.ts:1227

Parameters ​
name ​

string

type ​

AVOptionTypeDuration

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | number

Inherited from ​

OptionMember.getOption

Call Signature ​

getOption(name, type, searchFlags?): null | number

Defined in: src/lib/option.ts:1228

Parameters ​
name ​

string

type ​

AVOptionTypeConst

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | number

Inherited from ​

OptionMember.getOption

Call Signature ​

getOption(name, type, searchFlags?): null | number

Defined in: src/lib/option.ts:1231

Parameters ​
name ​

string

type ​

AVOptionTypeDouble

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | number

Inherited from ​

OptionMember.getOption

Call Signature ​

getOption(name, type, searchFlags?): null | number

Defined in: src/lib/option.ts:1232

Parameters ​
name ​

string

type ​

AVOptionTypeFloat

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | number

Inherited from ​

OptionMember.getOption

Call Signature ​

getOption(name, type, searchFlags?): null | IRational

Defined in: src/lib/option.ts:1235

Parameters ​
name ​

string

type ​

AVOptionTypeRational

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | IRational

Inherited from ​

OptionMember.getOption

Call Signature ​

getOption(name, type, searchFlags?): null | IRational

Defined in: src/lib/option.ts:1236

Parameters ​
name ​

string

type ​

AVOptionTypeVideoRate

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | IRational

Inherited from ​

OptionMember.getOption

Call Signature ​

getOption(name, type, searchFlags?): null | AVPixelFormat

Defined in: src/lib/option.ts:1237

Parameters ​
name ​

string

type ​

AVOptionTypePixelFmt

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | AVPixelFormat

Inherited from ​

OptionMember.getOption

Call Signature ​

getOption(name, type, searchFlags?): null | AVSampleFormat

Defined in: src/lib/option.ts:1238

Parameters ​
name ​

string

type ​

AVOptionTypeSampleFmt

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | AVSampleFormat

Inherited from ​

OptionMember.getOption

Call Signature ​

getOption(name, type, searchFlags?): null | { height: number; width: number; }

Defined in: src/lib/option.ts:1239

Parameters ​
name ​

string

type ​

AVOptionTypeImageSize

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | { height: number; width: number; }

Inherited from ​

OptionMember.getOption

Call Signature ​

getOption(name, type, searchFlags?): null | ChannelLayout

Defined in: src/lib/option.ts:1240

Parameters ​
name ​

string

type ​

AVOptionTypeChLayout

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | ChannelLayout

Inherited from ​

OptionMember.getOption

Call Signature ​

getOption(name, type, searchFlags?): null | Dictionary

Defined in: src/lib/option.ts:1241

Parameters ​
name ​

string

type ​

AVOptionTypeDict

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | Dictionary

Inherited from ​

OptionMember.getOption

Call Signature ​

getOption(name, type, searchFlags?): null | string

Defined in: src/lib/option.ts:1242

Parameters ​
name ​

string

type ​

AVOptionTypeBinary

searchFlags? ​

AVOptionSearchFlags

Returns ​

null | string

Inherited from ​

OptionMember.getOption

init() ​

init(options): number

Defined in: src/lib/filter-context.ts:192

Initialize filter with dictionary options.

Configures the filter with key-value option pairs. Must be called after creation and before processing.

Direct mapping to avfilter_init_dict().

Parameters ​

options ​

Dictionary of filter options

null | NativeDictionary

Returns ​

number

0 on success, negative AVERROR on error:

  • AVERROR_EINVAL: Invalid parameters
  • AVERROR_ENOMEM: Memory allocation failure

Example ​

typescript
import { FFmpegError } from 'node-av';

const options = { width: '1920', height: '1080' };
const ret = context.init(options);
FFmpegError.throwIfError(ret, 'init');

See ​

initStr For string-based initialization

initStr() ​

initStr(args): number

Defined in: src/lib/filter-context.ts:225

Initialize filter with string arguments.

Configures the filter using a string representation of parameters. Format depends on the specific filter.

Direct mapping to avfilter_init_str().

Parameters ​

args ​

Filter arguments string

null | string

Returns ​

number

0 on success, negative AVERROR on error:

  • AVERROR_EINVAL: Invalid arguments
  • AVERROR_ENOMEM: Memory allocation failure

Example ​

typescript
import { FFmpegError } from 'node-av';

// Scale filter with width:height
const ret = scaleContext.initStr('1920:1080');
FFmpegError.throwIfError(ret, 'initStr');

// Crop filter with width:height:x:y
const ret2 = cropContext.initStr('640:480:100:50');
FFmpegError.throwIfError(ret2, 'initStr');

See ​

init For dictionary-based initialization

isReady() ​

isReady(): boolean

Defined in: src/lib/filter-context.ts:779

Check if filter is ready.

Indicates whether the filter is ready for processing.

Returns ​

boolean

True if filter is ready

Example ​

typescript
if (context.isReady()) {
  // Filter is ready for processing
}

isSink() ​

isSink(): boolean

Defined in: src/lib/filter-context.ts:761

Check if filter is a sink.

Sink filters consume frames without output.

Returns ​

boolean

True if filter has no outputs

Example ​

typescript
if (context.isSink()) {
  console.log('This is a sink filter');
}

See ​

isSource To check for source filters

isSource() ​

isSource(): boolean

Defined in: src/lib/filter-context.ts:741

Check if filter is a source.

Source filters generate frames without input.

Returns ​

boolean

True if filter has no inputs

Example ​

typescript
if (context.isSource()) {
  console.log('This is a source filter');
}

See ​

isSink To check for sink filters

link(srcPad, dst, dstPad): number

Defined in: src/lib/filter-context.ts:262

Link this filter's output to another filter's input.

Creates a connection between two filters in the graph. Data flows from this filter's output pad to the destination's input pad.

Direct mapping to avfilter_link().

Parameters ​

srcPad ​

number

Output pad index of this filter

dst ​

FilterContext

Destination filter context

dstPad ​

number

Input pad index of destination filter

Returns ​

number

0 on success, negative AVERROR on error:

  • AVERROR_EINVAL: Invalid pad indices or incompatible formats
  • AVERROR_ENOMEM: Memory allocation failure

Example ​

typescript
import { FFmpegError } from 'node-av';

// Link source output 0 to scale input 0
const ret = source.link(0, scale, 0);
FFmpegError.throwIfError(ret, 'link');

// Link scale output 0 to sink input 0
const ret2 = scale.link(0, sink, 0);
FFmpegError.throwIfError(ret2, 'link');

See ​

unlink To disconnect filters

listOptions() ​

listOptions(): OptionInfo[]

Defined in: src/lib/option.ts:1358

List all available options for this object.

Uses the AVOption API to enumerate all options. Useful for discovering available settings and their types.

Direct mapping to av_opt_next() iteration.

Returns ​

OptionInfo[]

Array of option information objects

Example ​

typescript
const options = obj.listOptions();
for (const opt of options) {
  console.log(`${opt.name}: ${opt.help}`);
  console.log(`  Type: ${opt.type}, Default: ${opt.defaultValue}`);
  console.log(`  Range: ${opt.min} - ${opt.max}`);
}

See ​

OptionInfo For option metadata structure

Inherited from ​

OptionMember.listOptions

setOption() ​

Set an option on this object.

Uses the AVOption API to set options. Available options depend on the specific object type.

Direct mapping to av_opt_set* functions.

Param ​

Option name

Param ​

Option value

Param ​

Option type (defaults to AV_OPT_TYPE_STRING)

Param ​

Search flags (default: AV_OPT_SEARCH_CHILDREN)

Example ​

typescript
import { FFmpegError } from 'node-av';
import { AV_OPT_TYPE_STRING, AV_OPT_TYPE_INT64, AV_OPT_TYPE_RATIONAL, AV_OPT_TYPE_PIXEL_FMT } from 'node-av/constants';

// String options (default)
let ret = obj.setOption('preset', 'fast');
FFmpegError.throwIfError(ret, 'set preset');

ret = obj.setOption('codec', 'h264', AV_OPT_TYPE_STRING);
FFmpegError.throwIfError(ret, 'set codec');

// Integer options
ret = obj.setOption('bitrate', 2000000, AV_OPT_TYPE_INT64);
FFmpegError.throwIfError(ret, 'set bitrate');

ret = obj.setOption('threads', 4, AV_OPT_TYPE_INT);
FFmpegError.throwIfError(ret, 'set threads');

// Complex types with proper types
ret = obj.setOption('framerate', {num: 30, den: 1}, AV_OPT_TYPE_RATIONAL);
FFmpegError.throwIfError(ret, 'set framerate');

ret = obj.setOption('pix_fmt', AV_PIX_FMT_YUV420P, AV_OPT_TYPE_PIXEL_FMT);
FFmpegError.throwIfError(ret, 'set pixel format');

Call Signature ​

setOption(name, value, type?, searchFlags?): number

Defined in: src/lib/option.ts:1006

Parameters ​
name ​

string

value ​

string

type? ​

AVOptionTypeString

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1007

Parameters ​
name ​

string

value ​

string

type ​

AVOptionTypeColor

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1010

Parameters ​
name ​

string

value ​

number

type ​

AVOptionTypeInt

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1011

Parameters ​
name ​

string

value ​

bigint

type ​

AVOptionTypeInt64

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1012

Parameters ​
name ​

string

value ​

number

type ​

AVOptionTypeUint

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1013

Parameters ​
name ​

string

value ​

bigint

type ​

AVOptionTypeUint64

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1014

Parameters ​
name ​

string

value ​

number

type ​

AVOptionTypeFlags

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1015

Parameters ​
name ​

string

value ​

boolean

type ​

AVOptionTypeBool

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1016

Parameters ​
name ​

string

value ​

number

type ​

AVOptionTypeDuration

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1017

Parameters ​
name ​

string

value ​

number

type ​

AVOptionTypeConst

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1020

Parameters ​
name ​

string

value ​

number

type ​

AVOptionTypeDouble

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1021

Parameters ​
name ​

string

value ​

number

type ​

AVOptionTypeFloat

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1024

Parameters ​
name ​

string

value ​

IRational

type ​

AVOptionTypeRational

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1025

Parameters ​
name ​

string

value ​

IRational

type ​

AVOptionTypeVideoRate

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1026

Parameters ​
name ​

string

value ​

AVPixelFormat

type ​

AVOptionTypePixelFmt

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1027

Parameters ​
name ​

string

value ​

AVSampleFormat

type ​

AVOptionTypeSampleFmt

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1028

Parameters ​
name ​

string

value ​
height ​

number

width ​

number

type ​

AVOptionTypeImageSize

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1029

Parameters ​
name ​

string

value ​

number | bigint

type ​

AVOptionTypeChLayout

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1030

Parameters ​
name ​

string

value ​

Buffer

type ​

AVOptionTypeBinary

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1031

Parameters ​
name ​

string

value ​

number[]

type ​

AVOptionTypeBinaryIntArray

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

Call Signature ​

setOption(name, value, type, searchFlags?): number

Defined in: src/lib/option.ts:1032

Parameters ​
name ​

string

value ​

Dictionary

type ​

AVOptionTypeDict

searchFlags? ​

AVOptionSearchFlags

Returns ​

number

Inherited from ​

OptionMember.setOption

unlink(pad): void

Defined in: src/lib/filter-context.ts:284

Unlink a filter pad.

Disconnects a pad from its linked filter. Used to reconfigure filter connections.

Direct mapping to avfilter_link_free().

Parameters ​

pad ​

number

Pad index to unlink

Returns ​

void

Example ​

typescript
// Disconnect output pad 0
context.unlink(0);

See ​

link To connect filters