OpenShot Library | libopenshot  0.1.9
Public Member Functions | Public Attributes | List of all members
openshot::FFmpegReader Class Reference

This class uses the FFmpeg libraries, to open video files and audio files, and return openshot::Frame objects for any frame in the file. More...

#include <FFmpegReader.h>

Inheritance diagram for openshot::FFmpegReader:
openshot::ReaderBase

Public Member Functions

void Close ()
 Close File. More...
 
 FFmpegReader (string path)
 
 FFmpegReader (string path, bool inspect_reader)
 
CacheMemoryGetCache ()
 Get the cache object used by this reader. More...
 
std::shared_ptr< FrameGetFrame (int64_t requested_frame)
 
bool IsOpen ()
 Determine if reader is open or closed. More...
 
string Json ()
 Get and Set JSON methods. More...
 
Json::Value JsonValue ()
 Generate Json::JsonValue for this object. More...
 
string Name ()
 Return the type name of the class. More...
 
void Open ()
 Open File - which is called by the constructor automatically. More...
 
void SetJson (string value)
 Load JSON string into this object. More...
 
void SetJsonValue (Json::Value root)
 Load Json::JsonValue into this object. More...
 
 ~FFmpegReader ()
 Destructor. More...
 
- Public Member Functions inherited from openshot::ReaderBase
void DisplayInfo ()
 Display file information in the standard output stream (stdout) More...
 
 ReaderBase ()
 Constructor for the base reader, where many things are initialized. More...
 
void SetMaxSize (int width, int height)
 Set Max Image Size (used for performance optimization) More...
 

Public Attributes

bool enable_seek
 
CacheMemory final_cache
 Final cache object used to hold final frames. More...
 
- Public Attributes inherited from openshot::ReaderBase
ReaderInfo info
 Information about the current media file. More...
 

Additional Inherited Members

- Protected Attributes inherited from openshot::ReaderBase
CriticalSection getFrameCriticalSection
 Section lock for multiple threads. More...
 
int max_height
 The maximium image height needed by this clip (used for optimizations) More...
 
int max_width
 The maximum image width needed by this clip (used for optimizations) More...
 
CriticalSection processingCriticalSection
 

Detailed Description

This class uses the FFmpeg libraries, to open video files and audio files, and return openshot::Frame objects for any frame in the file.

All seeking and caching is handled internally, and the primary public interface is the GetFrame() method. To use this reader, simply create an instance of this class, and call the GetFrame method to start retrieving frames. Use the info struct to obtain information on the file, such as the length (# of frames), height, width, bit rate, frames per second (fps), etc...

// Create a reader for a video
FFmpegReader r("MyAwesomeVideo.webm");
r.Open(); // Open the reader
// Get frame number 1 from the video
std::shared_ptr<Frame> f = r.GetFrame(1);
// Now that we have an openshot::Frame object, lets have some fun!
f->Display(); // Display the frame on the screen
f->DisplayWaveform(); // Display the audio waveform as an image
f->Play(); // Play the audio through your speaker
// Close the reader
r.Close();

Definition at line 92 of file FFmpegReader.h.

Constructor & Destructor Documentation

◆ FFmpegReader() [1/2]

FFmpegReader::FFmpegReader ( string  path)

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

Definition at line 35 of file FFmpegReader.cpp.

◆ FFmpegReader() [2/2]

FFmpegReader::FFmpegReader ( string  path,
bool  inspect_reader 
)

Constructor for FFmpegReader. This only opens the media file to inspect it's properties if inspect_reader=true. When not inspecting the media file, it's much faster, and useful when you are inflating the object using JSON after instantiating it.

Definition at line 56 of file FFmpegReader.cpp.

◆ ~FFmpegReader()

FFmpegReader::~FFmpegReader ( )

Destructor.

Definition at line 79 of file FFmpegReader.cpp.

Member Function Documentation

◆ Close()

void FFmpegReader::Close ( )
virtual

Close File.

Implements openshot::ReaderBase.

Definition at line 203 of file FFmpegReader.cpp.

◆ GetCache()

CacheMemory* openshot::FFmpegReader::GetCache ( )
inlinevirtual

Get the cache object used by this reader.

Implements openshot::ReaderBase.

Definition at line 244 of file FFmpegReader.h.

◆ GetFrame()

std::shared_ptr< Frame > FFmpegReader::GetFrame ( int64_t  requested_frame)
virtual

Get a shared pointer to a openshot::Frame object for a specific frame number of this reader.

Returns
The requested frame of video
Parameters
requested_frameThe frame number that is requested.

Implements openshot::ReaderBase.

Definition at line 396 of file FFmpegReader.cpp.

◆ IsOpen()

bool openshot::FFmpegReader::IsOpen ( )
inlinevirtual

Determine if reader is open or closed.

Implements openshot::ReaderBase.

Definition at line 253 of file FFmpegReader.h.

◆ Json()

string FFmpegReader::Json ( )
virtual

Get and Set JSON methods.

Generate JSON string of this object

Implements openshot::ReaderBase.

Definition at line 1914 of file FFmpegReader.cpp.

◆ JsonValue()

Json::Value FFmpegReader::JsonValue ( )
virtual

Generate Json::JsonValue for this object.

Implements openshot::ReaderBase.

Definition at line 1921 of file FFmpegReader.cpp.

◆ Name()

string openshot::FFmpegReader::Name ( )
inlinevirtual

Return the type name of the class.

Implements openshot::ReaderBase.

Definition at line 256 of file FFmpegReader.h.

◆ Open()

void FFmpegReader::Open ( )
virtual

Open File - which is called by the constructor automatically.

Implements openshot::ReaderBase.

Definition at line 104 of file FFmpegReader.cpp.

◆ SetJson()

void FFmpegReader::SetJson ( string  value)
virtual

Load JSON string into this object.

Implements openshot::ReaderBase.

Definition at line 1933 of file FFmpegReader.cpp.

◆ SetJsonValue()

void FFmpegReader::SetJsonValue ( Json::Value  root)
virtual

Load Json::JsonValue into this object.

Implements openshot::ReaderBase.

Definition at line 1956 of file FFmpegReader.cpp.

Member Data Documentation

◆ enable_seek

bool openshot::FFmpegReader::enable_seek

Enable or disable seeking. Seeking can more quickly locate the requested frame, but some codecs have trouble seeking, and can introduce artifacts or blank images into the video.

Definition at line 226 of file FFmpegReader.h.

◆ final_cache

CacheMemory openshot::FFmpegReader::final_cache

Final cache object used to hold final frames.

Definition at line 222 of file FFmpegReader.h.


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