This class reads a special chunk-formatted file, which can be easily shared in a distributed environment. More...

#include <ChunkReader.h>

Inheritance diagram for openshot::ChunkReader:

Collaboration diagram for openshot::ChunkReader:

Public Member Functions
	ChunkReader (std::string path, ChunkVersion chunk_version)
	Constructor for ChunkReader. This automatically opens the chunk file or folder and loads frame 1, or it throws one of the following exceptions. More...

void	Close () override
	Close the reader. More...

openshot::CacheBase *	GetCache () override
	Get the cache object used by this reader (always return NULL for this reader) More...

int64_t	GetChunkSize ()
	Get the chunk size (number of frames to write in each chunk) More...

std::shared_ptr< openshot::Frame >	GetFrame (int64_t requested_frame) override
	Get an openshot::Frame object for a specific frame number of this reader. More...

bool	IsOpen () override
	Determine if reader is open or closed. More...

std::string	Json () const override
	Generate JSON string of this object. More...

Json::Value	JsonValue () const override
	Generate Json::Value for this object. More...

std::string	Name () override
	Return the type name of the class. More...

void	Open () override
	Open the reader. This is required before you can access frames or data from the reader. More...

void	SetChunkSize (int64_t new_size)
	Set the chunk size (number of frames to write in each chunk) More...

void	SetJson (const std::string value) override
	Load JSON string into this object. More...

void	SetJsonValue (const Json::Value root) override
	Load Json::Value into this object. More...

Public Member Functions inherited from openshot::ReaderBase
void	DisplayInfo (std::ostream *out=&std::cout)
	Display file information in the standard output stream (stdout) More...

openshot::ClipBase *	ParentClip ()
	Parent clip object of this reader (which can be unparented and NULL) More...

void	ParentClip (openshot::ClipBase *new_clip)
	Set parent clip object of this reader. More...

	ReaderBase ()
	Constructor for the base reader, where many things are initialized. More...

virtual	~ReaderBase ()=default

Additional Inherited Members
Public Attributes inherited from openshot::ReaderBase
openshot::ReaderInfo	info
	Information about the current media file. More...

Protected Attributes inherited from openshot::ReaderBase
openshot::ClipBase *	clip
	Pointer to the parent clip instance (if any) More...

std::recursive_mutex	getFrameMutex
	Mutex for multiple threads. More...

Detailed Description

This class reads a special chunk-formatted file, which can be easily shared in a distributed environment.

It stores the video in small "chunks", which are really just short video clips, a few seconds each. A ChunkReader only needs the part of the chunk that contains the frames it is looking for. For example, if you only need the end of a video, only the last few chunks might be needed to successfully access those openshot::Frame objects.

// This example demonstrates how to read a chunk folder and access frame objects inside it.
ChunkReader r("/home/jonathan/apps/chunks/chunk1/", FINAL); // Load highest quality version of this chunk file
r.DisplayInfo(); // Display all known details about this chunk file
r.Open(); // Open the reader
 
// Access frame 1
r.GetFrame(1)->Display();
 
// Close the reader
r.Close();

Definition at line 78 of file ChunkReader.h.

Constructor & Destructor Documentation

◆ ChunkReader()

ChunkReader::ChunkReader	(	std::string	path,
		ChunkVersion	chunk_version
	)

Constructor for ChunkReader. This automatically opens the chunk file or folder and loads frame 1, or it throws one of the following exceptions.

Parameters

path	The folder path / location of a chunk (chunks are stored as folders)
chunk_version	Choose the video version / quality (THUMBNAIL, PREVIEW, or FINAL)

Definition at line 23 of file ChunkReader.cpp.

Member Function Documentation

◆ Close()

void ChunkReader::Close ( )

overridevirtual

Close the reader.

Implements openshot::ReaderBase.

Definition at line 149 of file ChunkReader.cpp.

Referenced by ChunkReader(), and SetJsonValue().

◆ GetCache()

openshot::CacheBase* openshot::ChunkReader::GetCache ( )

inlineoverridevirtual

Get the cache object used by this reader (always return NULL for this reader)

Implements openshot::ReaderBase.

Definition at line 121 of file ChunkReader.h.

◆ GetChunkSize()

int64_t openshot::ChunkReader::GetChunkSize ( )

inline

Get the chunk size (number of frames to write in each chunk)

Returns: The number of frames in this chunk

Definition at line 114 of file ChunkReader.h.

◆ GetFrame()

std::shared_ptr< Frame > ChunkReader::GetFrame ( int64_t requested_frame )

overridevirtual

Get an openshot::Frame object for a specific frame number of this reader.

Returns: The requested frame (containing the image and audio)

Parameters

requested_frame The frame number you want to retrieve

Implements openshot::ReaderBase.

Definition at line 183 of file ChunkReader.cpp.

◆ IsOpen()

bool openshot::ChunkReader::IsOpen ( )

inlineoverridevirtual

Determine if reader is open or closed.

Implements openshot::ReaderBase.

Definition at line 129 of file ChunkReader.h.

◆ Json()

std::string ChunkReader::Json ( ) const

overridevirtual

Generate JSON string of this object.

Implements openshot::ReaderBase.

Definition at line 244 of file ChunkReader.cpp.

◆ JsonValue()

Json::Value ChunkReader::JsonValue ( ) const

overridevirtual

Generate Json::Value for this object.

Implements openshot::ReaderBase.

Definition at line 251 of file ChunkReader.cpp.

Referenced by Json().

◆ Name()

std::string openshot::ChunkReader::Name ( )

inlineoverridevirtual

Return the type name of the class.

Implements openshot::ReaderBase.

Definition at line 132 of file ChunkReader.h.

◆ Open()

void ChunkReader::Open ( )

overridevirtual

Open the reader. This is required before you can access frames or data from the reader.

Implements openshot::ReaderBase.

Definition at line 135 of file ChunkReader.cpp.

Referenced by ChunkReader(), and SetJsonValue().

◆ SetChunkSize()

void openshot::ChunkReader::SetChunkSize ( int64_t new_size )

inline

Set the chunk size (number of frames to write in each chunk)

Parameters

new_size The number of frames per chunk

Definition at line 118 of file ChunkReader.h.

◆ SetJson()

void ChunkReader::SetJson ( const std::string value )

overridevirtual

Load JSON string into this object.

Implements openshot::ReaderBase.

Definition at line 267 of file ChunkReader.cpp.

◆ SetJsonValue()

void ChunkReader::SetJsonValue ( const Json::Value root )

overridevirtual

Load Json::Value into this object.

Implements openshot::ReaderBase.

Definition at line 283 of file ChunkReader.cpp.

Referenced by SetJson().

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

Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ ChunkReader()

Member Function Documentation

◆ Close()

◆ GetCache()

◆ GetChunkSize()

◆ GetFrame()

◆ IsOpen()

◆ Json()

◆ JsonValue()

◆ Name()

◆ Open()

◆ SetChunkSize()

◆ SetJson()

◆ SetJsonValue()