AV module - icey

Namespaces

Name	Description
`v4l2`	Linux V4L2 device enumeration helpers.
`coreaudio`	Apple CoreAudio device enumeration helpers.
`legacy`	Legacy timing helpers kept for compatibility with older media pipelines.
`avfoundation`	Apple AVFoundation device enumeration helpers.
`mediafoundation`	Windows Media Foundation device enumeration helpers.
`wasapi`	Windows WASAPI device enumeration helpers.

Classes

Name	Description
`LinuxDeviceWatcher`	Monitors device add/remove events via libudev.
`ICapture`	Abstract interface for audio and video capture devices.
`IEncoder`	This is the abstract class for all encoders.
`AppleDeviceWatcher`	Monitors device add/remove events via AVFoundation notifications and CoreAudio property listeners.
`FPSCounter`	FPS counter based on the simple moving average (SMA) algorithm.
`FPSLimiter`	PacketStream processor that caps packet throughput to a maximum FPS.
`AudioCapture`	Cross-platform audio capture device backed by FFmpeg input devices.
`MediaCapture`	Unified capture and decode source for files and live media devices.
`VideoCapture`	Cross-platform video device capturer backed by FFmpeg avdevice.
`DeviceWatcher`	Base class for platform-specific device change monitors.
`DeviceManager`	Enumerates and manages system audio and video devices.
`FormatRegistry`	Singleton registry of available media container formats for encoding and decoding.
`WindowsDeviceWatcher`	Monitors device add/remove events via IMMNotificationClient (audio) and RegisterDeviceNotification (video).
`MultiplexEncoder`	Multiplexing encoder that writes synchronized audio and video streams.
`AudioPacketEncoder`	PacketProcessor that encodes raw audio samples (PlanarAudioPacket or AudioPacket) into compressed packets via AudioEncoder.
`VideoPacketEncoder`	PacketProcessor that encodes raw video frames (PlanarVideoPacket or VideoPacket) into compressed packets via VideoEncoder.
`RealtimePacketQueue`	Queue that emits media packets in presentation-timestamp order relative to a realtime clock.
`MultiplexPacketEncoder`	Encodes and multiplexes a realtime video stream form audio / video capture sources. FFmpeg is used for encoding.
`Codec`	Codec for encoding/decoding media.
`AudioCodec`	Audio codec parameters including channels, sample rate, and sample format.
`VideoCodec`	Video codec parameters including resolution, frame rate, and pixel format.
`Deleter`	RAII helpers for owning FFmpeg allocation types.
`Deleterp`	Deleter adaptor for functions like av_freep that take a pointer to a pointer.
`Format`	Defines a media container format which is available through the FormatRegistry for encoding or decoding.
`EncoderState`	State machine states for the encoder pipeline.
`EncoderOptions`	Configuration options for audio and video encoders.
`AudioBuffer`	FIFO buffer for queuing audio samples between encoding stages.
`AudioContext`	Base context for audio encoding and decoding via FFmpeg.
`AudioDecoder`	Decodes compressed audio packets into raw sample frames.
`AudioEncoder`	Encodes raw audio samples into a compressed format.
`VideoContext`	Base video context from which all video encoders and decoders derive.
`VideoDecoder`	Decodes compressed video packets into raw frames.
`VideoEncoder`	Encodes raw video frames into a compressed format.
`Device`	Represents a system audio, video or render device.
`AudioResampler`	Converts audio samples between different formats, sample rates, and channel layouts.
`VideoConverter`	Converts video frames between pixel formats and resolutions.
`MediaPacket`	Timestamped media packet carrying raw audio or video data.
`VideoPacket`	Video packet for interleaved formats.
`PlanarVideoPacket`	Video packet for planar formats.
`AudioPacket`	Audio packet for interleaved formats.
`PlanarAudioPacket`	Audio packet for planar formats.

Macros

Name	Description
`MAX_VIDEO_PACKET_SIZE`
`MAX_AUDIO_PACKET_SIZE`	1 second of 48khz 32bit audio
`MAX_ENCODE_DURATION`	3 hours
`INT64_C`
`UINT64_C`
`AV_API`
`DEFAULT_AUDIO_SAMPLE_RATE`
`DEFAULT_AUDIO_BIT_RATE`
`DEFAULT_AUDIO_CHANNELS`
`DEFAULT_AUDIO_SAMPLE_FMT`
`DEFAULT_VIDEO_SAMPLE_RATE`
`DEFAULT_VIDEO_BIT_RATE`
`DEFAULT_VIDEO_PIXEL_FMT`

MAX_VIDEO_PACKET_SIZE

#define MAX_VIDEO_PACKET_SIZE (3 * 1024 * 1024)

Defined in src/av/include/icy/av/av.h:20

MAX_AUDIO_PACKET_SIZE

#define MAX_AUDIO_PACKET_SIZE (128 * 1500)

Defined in src/av/include/icy/av/av.h:21

1 second of 48khz 32bit audio

MAX_ENCODE_DURATION

#define MAX_ENCODE_DURATION (3 * 60 * 60 * 1000)

Defined in src/av/include/icy/av/av.h:22

3 hours

INT64_C

#define INT64_C(c) (c##LL)

Defined in src/av/include/icy/av/av.h:32

UINT64_C

#define UINT64_C(c) (c##ULL)

Defined in src/av/include/icy/av/av.h:35

AV_API

#define AV_API ICY_IMPORT

Defined in src/av/include/icy/av/av.h:43

DEFAULT_AUDIO_SAMPLE_RATE

#define DEFAULT_AUDIO_SAMPLE_RATE 44100

Defined in src/av/include/icy/av/codec.h:95

DEFAULT_AUDIO_BIT_RATE

#define DEFAULT_AUDIO_BIT_RATE 64000

Defined in src/av/include/icy/av/codec.h:96

DEFAULT_AUDIO_CHANNELS

#define DEFAULT_AUDIO_CHANNELS 2

Defined in src/av/include/icy/av/codec.h:97

DEFAULT_AUDIO_SAMPLE_FMT

#define DEFAULT_AUDIO_SAMPLE_FMT "s16"

Defined in src/av/include/icy/av/codec.h:98

DEFAULT_VIDEO_SAMPLE_RATE

#define DEFAULT_VIDEO_SAMPLE_RATE 384000

Defined in src/av/include/icy/av/codec.h:163

DEFAULT_VIDEO_BIT_RATE

#define DEFAULT_VIDEO_BIT_RATE 400000

Defined in src/av/include/icy/av/codec.h:164

DEFAULT_VIDEO_PIXEL_FMT

#define DEFAULT_VIDEO_PIXEL_FMT "yuv420p"

Defined in src/av/include/icy/av/codec.h:165

Enumerations

Name	Description
`MediaCapabilities`	Bitmask of media capabilities detected on this system.

MediaCapabilities

enum MediaCapabilities

Defined in src/av/include/icy/av/devicemanager.h:177

Bitmask of media capabilities detected on this system.

Value	Description
`AUDIO_RECV`	Audio capture or decode is available.
`AUDIO_SEND`	Audio playback or encode is available.
`VIDEO_RECV`	Video capture or decode is available.
`VIDEO_SEND`	Video render or encode is available.

Typedefs

Return	Name	Description
std::list< `Codec` >	`CodecList`	List of codec value objects.
std::list< `Codec` * >	`CodecPList`	List of codec pointers.
std::unique_ptr< AVFrame, `Deleterp`< AVFrame, void, av_frame_free > >	`AVFrameHolder`	Owning AVFrame pointer released with av_frame_free().
std::unique_ptr< AVFormatContext, `Deleter`< AVFormatContext, void, avformat_free_context > >	`AVFormatContextHolder`	Owning AVFormatContext pointer released with avformat_free_context().
std::unique_ptr< AVCodecContext, `Deleterp`< AVCodecContext, void, avcodec_free_context > >	`AVCodecContextHolder`	Owning AVCodecContext pointer released with avcodec_free_context().
std::unique_ptr< AVDictionary , `Deleter`< AVDictionary , void, av_dict_free > >	`AVDictionaryCleanup`	Cleanup wrapper for AVDictionary* values freed with av_dict_free().
std::unique_ptr< AVPacket, `Deleterp`< AVPacket, void, av_packet_free > >	`AVPacketHolder`	Owning AVPacket pointer released with av_packet_free().
std::vector< `Format` >	`FormatList`	List of container format value objects.
std::vector< `Format` * >	`FormatPList`	List of container format pointers.
`IEncoder`	`IPacketEncoder`	Legacy alias for IEncoder kept for 0.8.x compatibility.

CodecList

using CodecList = std::list< Codec >

Type: std::list< Codec >

Defined in src/av/include/icy/av/codec.h:231

List of codec value objects.

CodecPList

using CodecPList = std::list< Codec * >

Type: std::list< Codec * >

Defined in src/av/include/icy/av/codec.h:232

List of codec pointers.

AVFrameHolder

using AVFrameHolder = std::unique_ptr< AVFrame, Deleterp< AVFrame, void, av_frame_free > >

Type: std::unique_ptr< AVFrame, Deleterp< AVFrame, void, av_frame_free > >

Defined in src/av/include/icy/av/ffmpeg.h:90

Owning AVFrame pointer released with av_frame_free().

AVFormatContextHolder

using AVFormatContextHolder = std::unique_ptr< AVFormatContext, Deleter< AVFormatContext, void, avformat_free_context > >

Type: std::unique_ptr< AVFormatContext, Deleter< AVFormatContext, void, avformat_free_context > >

Defined in src/av/include/icy/av/ffmpeg.h:94

Owning AVFormatContext pointer released with avformat_free_context().

AVCodecContextHolder

using AVCodecContextHolder = std::unique_ptr< AVCodecContext, Deleterp< AVCodecContext, void, avcodec_free_context > >

Type: std::unique_ptr< AVCodecContext, Deleterp< AVCodecContext, void, avcodec_free_context > >

Defined in src/av/include/icy/av/ffmpeg.h:98

Owning AVCodecContext pointer released with avcodec_free_context().

AVDictionaryCleanup

using AVDictionaryCleanup = std::unique_ptr< AVDictionary *, Deleter< AVDictionary *, void, av_dict_free > >

Type: std::unique_ptr< AVDictionary *, Deleter< AVDictionary *, void, av_dict_free > >

Defined in src/av/include/icy/av/ffmpeg.h:102

Cleanup wrapper for AVDictionary* values freed with av_dict_free().

AVPacketHolder

using AVPacketHolder = std::unique_ptr< AVPacket, Deleterp< AVPacket, void, av_packet_free > >

Type: std::unique_ptr< AVPacket, Deleterp< AVPacket, void, av_packet_free > >

Defined in src/av/include/icy/av/ffmpeg.h:106

Owning AVPacket pointer released with av_packet_free().

FormatList

using FormatList = std::vector< Format >

Type: std::vector< Format >

Defined in src/av/include/icy/av/format.h:113

List of container format value objects.

FormatPList

using FormatPList = std::vector< Format * >

Type: std::vector< Format * >

Defined in src/av/include/icy/av/format.h:114

List of container format pointers.

IPacketEncoder

using IPacketEncoder = IEncoder

Type: IEncoder

Defined in src/av/include/icy/av/iencoder.h:144

Legacy alias for IEncoder kept for 0.8.x compatibility.

Functions

Return	Name	Description
`int64_t`	`fpsToInterval` inline	Convert a frame rate to a nanosecond frame interval.
`int`	`intervalToFps` inline	Convert a nanosecond frame interval to a frame rate.
`float`	`intervalToFpsFloat` inline	Convert a nanosecond frame interval to a floating-point frame rate.
`void`	`initializeFFmpeg`	Initialize the FFmpeg library.
`void`	`uninitializeFFmpeg`	Uninitializes the FFmpeg library.
`std::string`	`averror`	Get an error string for the given error code.
`void`	`printInputFormats`	Print all available FFmpeg demuxer (input) format names to the given stream.
`void`	`printOutputFormats`	Print all available FFmpeg muxer (output) format names to the given stream.
`void`	`printEncoders`	Print all available FFmpeg encoder names to the given stream.
`AVPacketHolder`	`makeOwnedPacket`	Allocate an owning AVPacket with FFmpeg-required padding and timestamp metadata. The packet payload is copied into FFmpeg-managed storage, which is required by decoders such as H.264 that may overread AV_INPUT_BUFFER_PADDING_SIZE bytes.
`void`	`initAudioCodecFromContext`	Populate an AudioCodec from an open AVCodecContext.
`AVSampleFormat`	`selectSampleFormat`	Select the best supported sample format for a codec given the requested parameters. Returns the requested format if supported, otherwise the first format with the same planarity.
`bool`	`isSampleFormatSupported`	Check whether a specific sample format is in the codec's supported list.
`bool`	`formatIsPlanar`	Return true if the named sample format is planar (e.g. "fltp", "s16p").
`bool`	`formatIsPlanar`	Return true if the given AVSampleFormat is planar.
`AVFrame *`	`createVideoFrame`	Allocate a new AVFrame with the given pixel format and dimensions. Uses av_frame_get_buffer for reference-counted allocation with 16-byte alignment.
`AVFrame *`	`cloneVideoFrame`	Perform a deep copy of an AVFrame including its buffer data and properties.
`void`	`initVideoCodecFromContext`	Populate a VideoCodec from an open AVStream and AVCodecContext.
`AVPixelFormat`	`selectPixelFormat`	Select the best supported pixel format for a codec given the requested parameters. Returns the requested format if supported, otherwise the first format with the same plane count.
`std::optional< std::pair< const AVInputFormat *, std::string > >`	`parseDeviceUrl`	Parse a libavdevice URL scheme.

fpsToInterval

inline

inline int64_t fpsToInterval(int fps)

Defined in src/av/include/icy/av/codec.h:241

Convert a frame rate to a nanosecond frame interval.

Returns

The interval in nanoseconds between frames, or the minimum interval if fps is zero.

Parameters

Parameter	Type	Description
`fps`	`int`	The frame rate in frames per second.

intervalToFps

inline

inline int intervalToFps(int64_t interval)

Defined in src/av/include/icy/av/codec.h:251

Convert a nanosecond frame interval to a frame rate.

Returns

The frame rate in frames per second, or zero if interval is zero.

Parameters

Parameter	Type	Description
`interval`	`int64_t`	The nanosecond interval between frames.

intervalToFpsFloat

inline

inline float intervalToFpsFloat(int64_t interval)

Defined in src/av/include/icy/av/codec.h:263

Convert a nanosecond frame interval to a floating-point frame rate.

Returns

The frame rate in frames per second as a float, or 0.0f if interval is zero.

Parameters

Parameter	Type	Description
`interval`	`int64_t`	The nanosecond interval between frames.

initializeFFmpeg

void initializeFFmpeg()

Defined in src/av/include/icy/av/ffmpeg.h:39

Initialize the FFmpeg library.

uninitializeFFmpeg

void uninitializeFFmpeg()

Defined in src/av/include/icy/av/ffmpeg.h:42

Uninitializes the FFmpeg library.

averror

std::string averror(const int error)

Defined in src/av/include/icy/av/ffmpeg.h:45

Get an error string for the given error code.

printInputFormats

void printInputFormats(std::ostream & ost, const char * delim = " ")

Defined in src/av/include/icy/av/ffmpeg.h:50

Print all available FFmpeg demuxer (input) format names to the given stream.

Parameters

Parameter	Type	Description
`ost`	`std::ostream &`	The output stream to write to.
`delim`	`const char *`	Delimiter inserted between each name.

printOutputFormats

void printOutputFormats(std::ostream & ost, const char * delim = " ")

Defined in src/av/include/icy/av/ffmpeg.h:55

Print all available FFmpeg muxer (output) format names to the given stream.

Parameters

Parameter	Type	Description
`ost`	`std::ostream &`	The output stream to write to.
`delim`	`const char *`	Delimiter inserted between each name.

printEncoders

void printEncoders(std::ostream & ost, const char * delim = " ")

Defined in src/av/include/icy/av/ffmpeg.h:60

Print all available FFmpeg encoder names to the given stream.

Parameters

Parameter	Type	Description
`ost`	`std::ostream &`	The output stream to write to.
`delim`	`const char *`	Delimiter inserted between each name.

makeOwnedPacket

AVPacketHolder makeOwnedPacket(const MediaPacket & packet, int streamIndex, AVRational timeBase)

Defined in src/av/include/icy/av/ffmpeg.h:113

Allocate an owning AVPacket with FFmpeg-required padding and timestamp metadata. The packet payload is copied into FFmpeg-managed storage, which is required by decoders such as H.264 that may overread AV_INPUT_BUFFER_PADDING_SIZE bytes.

initAudioCodecFromContext

void initAudioCodecFromContext(const AVCodecContext * ctx, AudioCodec & params)

Defined in src/av/include/icy/av/audiocontext.h:112

Populate an AudioCodec from an open AVCodecContext.

Parameters

Parameter	Type	Description
`ctx`	`const AVCodecContext *`	The FFmpeg codec context to read from.
`params`	`AudioCodec` &	The AudioCodec struct to fill with codec, channel, sample rate, and format info.

selectSampleFormat

AVSampleFormat selectSampleFormat(const AVCodec * codec, av::AudioCodec & params)

Defined in src/av/include/icy/av/audiocontext.h:119

Select the best supported sample format for a codec given the requested parameters. Returns the requested format if supported, otherwise the first format with the same planarity.

Returns

The chosen AVSampleFormat, or AV_SAMPLE_FMT_NONE if none is compatible.

Parameters

Parameter	Type	Description
`codec`	`const AVCodec *`	The FFmpeg codec whose supported formats are queried.
`params`	`av::AudioCodec` &	The audio codec parameters specifying the desired sample format.

isSampleFormatSupported

bool isSampleFormatSupported(const AVCodec * codec, enum AVSampleFormat sampleFormat)

Defined in src/av/include/icy/av/audiocontext.h:125

Check whether a specific sample format is in the codec's supported list.

Returns

True if the format is supported.

Parameters

Parameter	Type	Description
`codec`	`const AVCodec *`	The FFmpeg codec to query.
`sampleFormat`	`enum AVSampleFormat`	The AVSampleFormat to look up.

formatIsPlanar

bool formatIsPlanar(const std::string & pixfmt)

Defined in src/av/include/icy/av/audiocontext.h:129

Return true if the named sample format is planar (e.g. "fltp", "s16p").

Parameters

Parameter	Type	Description
`pixfmt`	`const std::string &`	The sample format name string.

formatIsPlanar

bool formatIsPlanar(AVSampleFormat format)

Defined in src/av/include/icy/av/audiocontext.h:133

Return true if the given AVSampleFormat is planar.

Parameters

Parameter	Type	Description
`format`	`AVSampleFormat`	The AVSampleFormat to check.

createVideoFrame

AVFrame * createVideoFrame(AVPixelFormat pixelFmt, int width, int height)

Defined in src/av/include/icy/av/videocontext.h:130

Allocate a new AVFrame with the given pixel format and dimensions. Uses av_frame_get_buffer for reference-counted allocation with 16-byte alignment.

Returns

A newly allocated AVFrame, or nullptr on failure.

Parameters

Parameter	Type	Description
`pixelFmt`	`AVPixelFormat`	The pixel format for the frame.
`width`	`int`	The frame width in pixels.
`height`	`int`	The frame height in pixels.

cloneVideoFrame

AVFrame * cloneVideoFrame(AVFrame * source)

Defined in src/av/include/icy/av/videocontext.h:135

Perform a deep copy of an AVFrame including its buffer data and properties.

Returns

A newly allocated AVFrame with copied data. Caller owns the result.

Parameters

Parameter	Type	Description
`source`	`AVFrame *`	The source frame to copy.

initVideoCodecFromContext

void initVideoCodecFromContext(const AVStream * stream, const AVCodecContext * ctx, VideoCodec & params)

Defined in src/av/include/icy/av/videocontext.h:141

Populate a VideoCodec from an open AVStream and AVCodecContext.

Parameters

Parameter	Type	Description
`stream`	`const AVStream *`	The AVStream for frame rate information (may be null).
`ctx`	`const AVCodecContext *`	The FFmpeg codec context to read from.
`params`	`VideoCodec` &	The VideoCodec struct to fill with codec, dimension, and format info.

selectPixelFormat

AVPixelFormat selectPixelFormat(const AVCodec * codec, VideoCodec & params)

Defined in src/av/include/icy/av/videocontext.h:148

Select the best supported pixel format for a codec given the requested parameters. Returns the requested format if supported, otherwise the first format with the same plane count.

Returns

The chosen AVPixelFormat.

Parameters

Parameter	Type	Description
`codec`	`const AVCodec *`	The FFmpeg codec whose supported formats are queried.
`params`	`VideoCodec` &	The video codec parameters specifying the desired pixel format.

parseDeviceUrl

std::optional< std::pair< const AVInputFormat *, std::string > > parseDeviceUrl(std::string_view source)

Defined in src/av/include/icy/av/devicemanager.h:358

Parse a libavdevice URL scheme.

Recognises: avfoundation: (macOS, e.g. "0:0", "0:none") v4l2: (Linux, e.g. "/dev/video0") dshow: (Windows, e.g. "video=Logitech HD WebCam")

On match returns the libavformat input format (looked up via av_find_input_format) and the portion of source after the scheme prefix. Returns std::nullopt for non-device sources (file paths, rtsp://, rtmp://, etc.), leaving the caller to use FFmpeg's auto-detection.

Throws std::runtime_error if a recognised scheme has no matching input format on this build (libavdevice not linked, or the backend is not compiled in on this platform).

Variables

Return	Name	Description
`constexpr int`	`kMaxPlanarAudioPlanes` static constexpr

kMaxPlanarAudioPlanes

static constexpr

constexpr int kMaxPlanarAudioPlanes = 8

Defined in src/av/include/icy/av/packet.h:26