RAII wrapper for AVFormatContext. More...

#include <ffmpeg_formatcontext.h>

Public Types
enum class	TYPE { INPUT , OUTPUT }
	Managed AVFormatContext direction. More...

Public Member Functions
	FFmpeg_FormatContext (TYPE type=TYPE::INPUT)
	Construct an empty format-context wrapper.

	~FFmpeg_FormatContext ()
	Release the owned format context, if any.

	FFmpeg_FormatContext (const FFmpeg_FormatContext &)=delete

FFmpeg_FormatContext &	operator= (const FFmpeg_FormatContext &)=delete

	FFmpeg_FormatContext (FFmpeg_FormatContext &&context) noexcept
	Move-construct a format-context wrapper.

FFmpeg_FormatContext &	operator= (FFmpeg_FormatContext &&context) noexcept
	Move-assign a format-context wrapper.

int	alloc_input_context ()
	Allocate a new input format context.

int	alloc_output_context (const char format_name, const char filename=nullptr)
	Allocate a new output format context.

void	set_type (TYPE type)
	Set the context direction used for later cleanup.

void	set_custom_io (bool custom_io=true)
	Mark whether the context owns a custom AVIOContext.

bool	reset ()
	Free the owned format context and reset the wrapper to empty.

bool	empty () const
	Check whether the wrapper currently owns a format context.

AVFormatContext *	get ()
	Get the owned FFmpeg format context pointer.

const AVFormatContext *	get () const
	Get the owned FFmpeg format context pointer.

AVFormatContext **	address ()
	Get a writable pointer-to-pointer for FFmpeg APIs.

AVFormatContext *	release ()
	Release ownership without freeing the format context.

	operator AVFormatContext * ()
	Convert to the underlying mutable format context pointer.

	operator const AVFormatContext * () const
	Convert to the underlying const format context pointer.

AVFormatContext *	operator-> ()
	Access members of the underlying mutable format context.

const AVFormatContext *	operator-> () const
	Access members of the underlying const format context.

Private Member Functions
void	free_custom_io ()
	Free the custom AVIOContext attached to the format context.

Private Attributes
AVFormatContext *	m_context
	Pointer to underlying AVFormatContext.

TYPE	m_type
	Input or output context.

bool	m_custom_io
	true if pb was allocated with avio_alloc_context().

Detailed Description

RAII wrapper for AVFormatContext.

Owns the AVFormatContext and releases it with the correct FFmpeg function. Input contexts are closed with avformat_close_input(), output contexts are released with avformat_free_context(). Custom AVIO contexts allocated with avio_alloc_context() are freed before the format context is released.

Definition at line 32 of file ffmpeg_formatcontext.h.

Member Enumeration Documentation

◆ TYPE

enum class FFmpeg_FormatContext::TYPE

strong

Managed AVFormatContext direction.

Enumerator
INPUT	Input context closed with avformat_close_input().
OUTPUT	Output context freed with avformat_free_context().

Definition at line 38 of file ffmpeg_formatcontext.h.

Constructor & Destructor Documentation

◆ FFmpeg_FormatContext() [1/2]

FFmpeg_FormatContext::FFmpeg_FormatContext ( TYPE type = TYPE::INPUT )

explicit

Construct an empty format-context wrapper.

Parameters

[in] type Initial context direction used when resetting/freeing.

Definition at line 33 of file ffmpeg_formatcontext.cc.

◆ ~FFmpeg_FormatContext()

FFmpeg_FormatContext::~FFmpeg_FormatContext ( )

Release the owned format context, if any.

Definition at line 40 of file ffmpeg_formatcontext.cc.

References reset().

◆ FFmpeg_FormatContext() [2/2]

FFmpeg_FormatContext::FFmpeg_FormatContext ( FFmpeg_FormatContext && context )

noexcept

Move-construct a format-context wrapper.

Parameters

[in,out] context Source wrapper whose context ownership is transferred.

Definition at line 45 of file ffmpeg_formatcontext.cc.

Member Function Documentation

◆ address()

AVFormatContext ** FFmpeg_FormatContext::address ( )

Get a writable pointer-to-pointer for FFmpeg APIs.

Any currently owned context is released first so that FFmpeg can write a fresh context pointer without leaking the previous one.

Returns: Address of the managed context pointer.

Definition at line 145 of file ffmpeg_formatcontext.cc.

References m_context.

Referenced by FFmpeg_Transcoder::open_input_file().

◆ alloc_input_context()

int FFmpeg_FormatContext::alloc_input_context ( )

Allocate a new input format context.

Returns: 0 on success, or a negative FFmpeg error code.

Definition at line 71 of file ffmpeg_formatcontext.cc.

References INPUT, m_context, m_type, and reset().

Referenced by FFmpeg_Transcoder::open_input_file().

◆ alloc_output_context()

int FFmpeg_FormatContext::alloc_output_context	(	const char *	format_name,
		const char *	filename = `nullptr`
	)

Allocate a new output format context.

Parameters

[in]	format_name	Output container format name, or nullptr for automatic selection.
[in]	filename	Optional output file name used by FFmpeg for format probing.

Returns: 0 on success, or a negative FFmpeg error code.

Definition at line 81 of file ffmpeg_formatcontext.cc.

References m_context, m_type, OUTPUT, and reset().

Referenced by FFmpeg_Transcoder::open_output_filestreams().

◆ empty()

bool FFmpeg_FormatContext::empty ( ) const

Check whether the wrapper currently owns a format context.

Returns: true if no format context is owned, false otherwise.

Definition at line 130 of file ffmpeg_formatcontext.cc.

References m_context.

◆ free_custom_io()

void FFmpeg_FormatContext::free_custom_io ( )

private

Free the custom AVIOContext attached to the format context.

Definition at line 180 of file ffmpeg_formatcontext.cc.

References m_context, and m_custom_io.

Referenced by reset().

◆ get() [1/2]

AVFormatContext * FFmpeg_FormatContext::get ( )

Get the owned FFmpeg format context pointer.

Returns: Mutable AVFormatContext pointer, or nullptr if empty.

Definition at line 135 of file ffmpeg_formatcontext.cc.

References m_context.

◆ get() [2/2]

const AVFormatContext * FFmpeg_FormatContext::get ( ) const

Get the owned FFmpeg format context pointer.

Returns: Const AVFormatContext pointer, or nullptr if empty.

Definition at line 140 of file ffmpeg_formatcontext.cc.

References m_context.

◆ operator AVFormatContext *()

FFmpeg_FormatContext::operator AVFormatContext * ( )

Convert to the underlying mutable format context pointer.

Definition at line 160 of file ffmpeg_formatcontext.cc.

◆ operator const AVFormatContext *()

FFmpeg_FormatContext::operator const AVFormatContext * ( ) const

Convert to the underlying const format context pointer.

Definition at line 165 of file ffmpeg_formatcontext.cc.

◆ operator->() [1/2]

AVFormatContext * FFmpeg_FormatContext::operator-> ( )

Access members of the underlying mutable format context.

Returns: Mutable AVFormatContext pointer.

Definition at line 170 of file ffmpeg_formatcontext.cc.

References m_context.

◆ operator->() [2/2]

const AVFormatContext * FFmpeg_FormatContext::operator-> ( ) const

Access members of the underlying const format context.

Returns: Const AVFormatContext pointer.

Definition at line 175 of file ffmpeg_formatcontext.cc.

References m_context.

◆ operator=()

FFmpeg_FormatContext & FFmpeg_FormatContext::operator= ( FFmpeg_FormatContext && context )

noexcept

Move-assign a format-context wrapper.

Parameters

[in,out] context Source wrapper whose context ownership is transferred.

Returns: Reference to this wrapper.

Definition at line 54 of file ffmpeg_formatcontext.cc.

◆ release()

AVFormatContext * FFmpeg_FormatContext::release ( )

Release ownership without freeing the format context.

Returns: Previously owned AVFormatContext pointer, or nullptr if empty.

Definition at line 150 of file ffmpeg_formatcontext.cc.

References m_context, and m_custom_io.

◆ reset()

bool FFmpeg_FormatContext::reset ( )

Free the owned format context and reset the wrapper to empty.

Returns: true if a context or custom IO object was released, false otherwise.

Definition at line 106 of file ffmpeg_formatcontext.cc.

References free_custom_io(), m_context, m_custom_io, m_type, and OUTPUT.

Referenced by alloc_input_context(), alloc_output_context(), FFmpeg_Transcoder::close_input_file(), FFmpeg_Transcoder::close_output_file(), FFmpeg_Transcoder::open_input_file(), and ~FFmpeg_FormatContext().

◆ set_custom_io()

void FFmpeg_FormatContext::set_custom_io ( bool custom_io = true )

Mark whether the context owns a custom AVIOContext.

Parameters

[in] custom_io true if pb was allocated with avio_alloc_context().

Definition at line 101 of file ffmpeg_formatcontext.cc.

References m_custom_io.

Referenced by FFmpeg_Transcoder::open_input_file(), and FFmpeg_Transcoder::open_output_filestreams().

◆ set_type()

void FFmpeg_FormatContext::set_type ( TYPE type )

Set the context direction used for later cleanup.

Parameters

[in] type Input or output context direction.

Definition at line 96 of file ffmpeg_formatcontext.cc.

References m_type.

Member Data Documentation

◆ m_context

AVFormatContext* FFmpeg_FormatContext::m_context

private

Pointer to underlying AVFormatContext.

Definition at line 166 of file ffmpeg_formatcontext.h.

Referenced by address(), alloc_input_context(), alloc_output_context(), empty(), free_custom_io(), get(), get(), operator->(), operator->(), release(), and reset().

◆ m_custom_io

bool FFmpeg_FormatContext::m_custom_io

private

true if pb was allocated with avio_alloc_context().

Definition at line 168 of file ffmpeg_formatcontext.h.

Referenced by free_custom_io(), release(), reset(), and set_custom_io().

◆ m_type

TYPE FFmpeg_FormatContext::m_type

private

Input or output context.

Definition at line 167 of file ffmpeg_formatcontext.h.

Referenced by alloc_input_context(), alloc_output_context(), reset(), and set_type().

The documentation for this class was generated from the following files:

src/ffmpeg_formatcontext.h
src/ffmpeg_formatcontext.cc

Public Types

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Member Enumeration Documentation

◆ TYPE

Constructor & Destructor Documentation

◆ FFmpeg_FormatContext() [1/2]

◆ ~FFmpeg_FormatContext()

◆ FFmpeg_FormatContext() [2/2]

Member Function Documentation

◆ address()

◆ alloc_input_context()

◆ alloc_output_context()

◆ empty()

◆ free_custom_io()

◆ get() [1/2]

◆ get() [2/2]

◆ operator AVFormatContext *()

◆ operator const AVFormatContext *()

◆ operator->() [1/2]

◆ operator->() [2/2]

◆ operator=()

◆ release()

◆ reset()

◆ set_custom_io()

◆ set_type()

Member Data Documentation

◆ m_context

◆ m_custom_io

◆ m_type