This class creates a preview image of a recording. More...

#include <libmythtv/previewgenerator.h>

Inheritance diagram for PreviewGenerator:

Collaboration diagram for PreviewGenerator:

Public Types
enum	Mode : std::uint8_t { kNone = 0x0, kLocal = 0x1, kRemote = 0x2, kLocalAndRemote = 0x3, kForceLocal = 0x5, kModeMask = 0x7 }

Public Slots
void	deleteLater ()

Public Member Functions
	PreviewGenerator (const ProgramInfo *pginfo, QString token, Mode mode=kLocal)
	Constructor. More...

void	SetPreviewTime (std::chrono::seconds time, long long frame)

void	SetPreviewTimeAsSeconds (std::chrono::seconds seconds)

void	SetPreviewTimeAsFrameNumber (long long frame_number)

void	SetOutputFilename (const QString &fileName)

void	SetOutputSize (const QSize size)

QString	GetToken (void) const

void	run (void) override
	Runs the Qt event loop unless we have a QRunnable, in which case we run the runnable run instead. More...

bool	Run (void)

void	AttachSignals (QObject *obj)

Public Member Functions inherited from MThread
	MThread (const QString &objectName)
	Standard constructor. More...

	MThread (const QString &objectName, QRunnable *runnable)
	Use this constructor if you want the default run() method to run the QRunnable's run() method instead of entering the Qt event loop. More...

virtual	~MThread ()

	MThread (const MThread &)=delete

MThread &	operator= (const MThread &)=delete

void	RunProlog (void)
	Sets up a thread, call this if you reimplement run(). More...

void	RunEpilog (void)
	Cleans up a thread's resources, call this if you reimplement run(). More...

QThread *	qthread (void)
	Returns the thread, this will always return the same pointer no matter how often you restart the thread. More...

void	setObjectName (const QString &name)

QString	objectName (void) const

void	setPriority (QThread::Priority priority)

QThread::Priority	priority (void) const

bool	isFinished (void) const

bool	isRunning (void) const

void	setStackSize (uint stackSize)

uint	stackSize (void) const

void	exit (int retcode=0)
	Use this to exit from the thread if you are using a Qt event loop. More...

void	start (QThread::Priority p=QThread::InheritPriority)
	Tell MThread to start running the thread in the near future. More...

void	terminate (void)
	Kill a thread unsafely. More...

void	quit (void)
	calls exit(0) More...

bool	wait (std::chrono::milliseconds time=std::chrono::milliseconds::max())
	Wait for the MThread to exit, with a maximum timeout. More...

Protected Member Functions
	~PreviewGenerator () override

void	TeardownAll (void)

bool	RemotePreviewRun (void)

bool	LocalPreviewRun (void)

bool	IsLocal (void) const

bool	RunReal (void)
	This call creates a preview without starting a new thread. More...

bool	event (QEvent *e) override

bool	SaveOutFile (const QByteArray &data, const QDateTime &dt)

Protected Member Functions inherited from MThread
int	exec (void)
	Enters the qt event loop. call exit or quit to exit thread. More...

Static Protected Member Functions
static char *	GetScreenGrab (const ProgramInfo &pginfo, const QString &filename, std::chrono::seconds seektime, long long seekframe, int &bufferlen, int &video_width, int &video_height, float &video_aspect)
	Returns a AV_PIX_FMT_RGBA32 buffer containg a frame from the video. More...

static bool	SavePreview (const QString &filename, const unsigned char *data, uint width, uint height, float aspect, int desired_width, int desired_height, const QString &format)

static QString	CreateAccessibleFilename (const QString &pathname, const QString &outFileName)

Static Protected Member Functions inherited from MThread
static void	setTerminationEnabled (bool enabled=true)

static void	usleep (std::chrono::microseconds time)

template<typename R , typename P >
static std::enable_if_t< std::chrono::treat_as_floating_point< R >::value, void >	usleep (std::chrono::duration< R, P > time)

Protected Attributes
QWaitCondition	m_previewWaitCondition

QMutex	m_previewLock

ProgramInfo	m_programInfo

Mode	m_mode

QObject *	m_listener {nullptr}

QString	m_pathname

std::chrono::seconds	m_captureTime {-1s}
	snapshot time in seconds or frame number (seconds has priority) More...

long long	m_captureFrame {-1}

QString	m_outFileName

QSize	m_outSize {0,0}

QString	m_outFormat {"PNG"}

QString	m_token

bool	m_gotReply {false}

bool	m_pixmapOk {false}

Protected Attributes inherited from MThread
MThreadInternal *	m_thread {nullptr}

QRunnable *	m_runnable {nullptr}

bool	m_prologExecuted {true}

bool	m_epilogExecuted {true}

Friends
int	preview_helper (uint chanid, QDateTime starttime, long long previewFrameNumber, std::chrono::seconds previewSeconds, QSize previewSize, const QString &infile, const QString &outfile)

Additional Inherited Members
Static Public Member Functions inherited from MThread
static void	ThreadSetup (const QString &name)
	This is to be called on startup in those few threads that haven't been ported to MThread. More...

static void	ThreadCleanup (void)
	This is to be called on exit in those few threads that haven't been ported to MThread. More...

static void	Cleanup (void)
	This will print out all the running threads, call exit(1) on each and then wait up to 5 seconds total for all the threads to exit. More...

static void	GetAllThreadNames (QStringList &list)

static void	GetAllRunningThreadNames (QStringList &list)

Detailed Description

This class creates a preview image of a recording.

The usage is simple: First, pass a ProgramInfo whose pathname points to a local or remote recording to the constructor. Then call either start(void) or Run(void) to generate the preview.

start(void) will create a thread that processes the request.

Run(void) will block until the preview completes.

The PreviewGenerator will send a PREVIEW_SUCCESS or a PREVIEW_FAILED event when the preview completes or fails.

Definition at line 27 of file previewgenerator.h.

Member Enumeration Documentation

◆ Mode

enum PreviewGenerator::Mode : std::uint8_t

Enumerator
kNone
kLocal
kRemote
kLocalAndRemote
kForceLocal
kModeMask

Definition at line 40 of file previewgenerator.h.

Constructor & Destructor Documentation

◆ PreviewGenerator()

PreviewGenerator::PreviewGenerator	(	const ProgramInfo *	pginfo,
		QString	token,
		PreviewGenerator::Mode	mode = `kLocal`
	)

Constructor.

ProgramInfo::pathname must include recording prefix, so that the file can be found on the file system for local preview generation. When called by the backend 'mode' should be set to kLocal, otherwise the backend may deadlock if the PreviewGenerator cannot find the file.

Parameters

pginfo	ProgramInfo for the recording we want a preview of.
token	A token value used to match up this request with the response from the backend. If a token isn't provided, the code will generate one.
mode	Specify the location where the file must exist in order to be processed.

Definition at line 73 of file previewgenerator.cpp.

◆ ~PreviewGenerator()

PreviewGenerator::~PreviewGenerator ( )

overrideprotected

Definition at line 87 of file previewgenerator.cpp.

Member Function Documentation

◆ SetPreviewTime()

void PreviewGenerator::SetPreviewTime	(	std::chrono::seconds	time,
		long long	frame
	)

inline

Definition at line 55 of file previewgenerator.h.

◆ SetPreviewTimeAsSeconds()

void PreviewGenerator::SetPreviewTimeAsSeconds ( std::chrono::seconds seconds )

inline

Definition at line 57 of file previewgenerator.h.

◆ SetPreviewTimeAsFrameNumber()

void PreviewGenerator::SetPreviewTimeAsFrameNumber ( long long frame_number )

inline

Definition at line 59 of file previewgenerator.h.

◆ SetOutputFilename()

void PreviewGenerator::SetOutputFilename ( const QString & fileName )

Definition at line 93 of file previewgenerator.cpp.

Referenced by SaveOutFile().

◆ SetOutputSize()

void PreviewGenerator::SetOutputSize ( const QSize size )

inline

Definition at line 62 of file previewgenerator.h.

◆ GetToken()

QString PreviewGenerator::GetToken ( void ) const

inline

Definition at line 64 of file previewgenerator.h.

Referenced by PreviewGeneratorQueue::SetPreviewGenerator().

◆ run()

void PreviewGenerator::run ( void )

overridevirtual

Runs the Qt event loop unless we have a QRunnable, in which case we run the runnable run instead.

Note: If you override this method you must call RunProlog before you do any work and RunEpilog before you exit the run method.

Reimplemented from MThread.

Definition at line 348 of file previewgenerator.cpp.

◆ Run()

bool PreviewGenerator::Run ( void )

Definition at line 208 of file previewgenerator.cpp.

Referenced by run().

◆ AttachSignals()

void PreviewGenerator::AttachSignals ( QObject * obj )

Definition at line 115 of file previewgenerator.cpp.

Referenced by PreviewGeneratorQueue::SetPreviewGenerator().

◆ deleteLater

void PreviewGenerator::deleteLater ( )

slot

Definition at line 109 of file previewgenerator.cpp.

Referenced by PreviewGeneratorQueue::SetPreviewGenerator().

◆ TeardownAll()

void PreviewGenerator::TeardownAll ( void )

protected

Definition at line 102 of file previewgenerator.cpp.

Referenced by deleteLater(), and ~PreviewGenerator().

◆ RemotePreviewRun()

bool PreviewGenerator::RemotePreviewRun ( void )

protected

Definition at line 355 of file previewgenerator.cpp.

Referenced by Run(), and RunReal().

◆ LocalPreviewRun()

bool PreviewGenerator::LocalPreviewRun ( void )

protected

Definition at line 634 of file previewgenerator.cpp.

Referenced by RunReal().

◆ IsLocal()

bool PreviewGenerator::IsLocal ( void ) const

protected

Definition at line 756 of file previewgenerator.cpp.

Referenced by Run(), and RunReal().

◆ RunReal()

bool PreviewGenerator::RunReal ( void )

protected

This call creates a preview without starting a new thread.

Definition at line 124 of file previewgenerator.cpp.

◆ GetScreenGrab()

char * PreviewGenerator::GetScreenGrab	(	const ProgramInfo &	pginfo,
		const QString &	filename,
		std::chrono::seconds	seektime,
		long long	seekframe,
		int &	bufferlen,
		int &	video_width,
		int &	video_height,
		float &	video_aspect
	)

staticprotected

Returns a AV_PIX_FMT_RGBA32 buffer containg a frame from the video.

Parameters

pginfo	Recording to grab from.
filename	File containing recording.
seektime	Seconds into the video to seek before capturing a frame. This field has priority. If it is set to -1s then seekframe will be used.
seekframe	Frames into the video to seek before capturing a frame.
bufferlen	Returns size of buffer returned (in bytes).
video_width	Returns width of frame grabbed.
video_height	Returns height of frame grabbed.
video_aspect	Returns aspect ratio of frame grabbed.

Returns: Buffer allocated with new containing frame in RGBA32 format if successful, nullptr otherwise.

Definition at line 795 of file previewgenerator.cpp.

Referenced by LocalPreviewRun().

◆ SavePreview()

bool PreviewGenerator::SavePreview	(	const QString &	filename,
		const unsigned char *	data,
		uint	width,
		uint	height,
		float	aspect,
		int	desired_width,
		int	desired_height,
		const QString &	format
	)

staticprotected

Definition at line 567 of file previewgenerator.cpp.

Referenced by LocalPreviewRun().

◆ CreateAccessibleFilename()

QString PreviewGenerator::CreateAccessibleFilename	(	const QString &	pathname,
		const QString &	outFileName
	)

staticprotected

Definition at line 725 of file previewgenerator.cpp.

Referenced by LocalPreviewRun().

◆ event()

bool PreviewGenerator::event ( QEvent * e )

overrideprotected

Definition at line 424 of file previewgenerator.cpp.

◆ SaveOutFile()

bool PreviewGenerator::SaveOutFile	(	const QByteArray &	data,
		const QDateTime &	dt
	)

protected

Definition at line 502 of file previewgenerator.cpp.

Referenced by event().

Friends And Related Function Documentation

◆ preview_helper

int preview_helper	(	uint	chanid,
		QDateTime	starttime,
		long long	previewFrameNumber,
		std::chrono::seconds	previewSeconds,
		QSize	previewSize,
		const QString &	infile,
		const QString &	outfile
	)

friend

Definition at line 66 of file mythpreviewgen.cpp.

Member Data Documentation

◆ m_previewWaitCondition

QWaitCondition PreviewGenerator::m_previewWaitCondition

protected

Definition at line 107 of file previewgenerator.h.

Referenced by event(), RemotePreviewRun(), and TeardownAll().

◆ m_previewLock

QMutex PreviewGenerator::m_previewLock

protected

Definition at line 108 of file previewgenerator.h.

Referenced by AttachSignals(), event(), RemotePreviewRun(), Run(), RunReal(), and TeardownAll().

◆ m_programInfo

ProgramInfo PreviewGenerator::m_programInfo

protected

Definition at line 109 of file previewgenerator.h.

Referenced by LocalPreviewRun(), RemotePreviewRun(), Run(), RunReal(), and SaveOutFile().

◆ m_mode

Mode PreviewGenerator::m_mode

protected

Definition at line 111 of file previewgenerator.h.

Referenced by Run(), and RunReal().

◆ m_listener

QObject* PreviewGenerator::m_listener {nullptr}

protected

Definition at line 112 of file previewgenerator.h.

Referenced by AttachSignals(), Run(), RunReal(), and TeardownAll().

◆ m_pathname

QString PreviewGenerator::m_pathname

protected

Definition at line 113 of file previewgenerator.h.

Referenced by IsLocal(), LocalPreviewRun(), Run(), and RunReal().

◆ m_captureTime

std::chrono::seconds PreviewGenerator::m_captureTime {-1s}

protected

snapshot time in seconds or frame number (seconds has priority)

Definition at line 116 of file previewgenerator.h.

Referenced by LocalPreviewRun(), RemotePreviewRun(), and Run().

◆ m_captureFrame

long long PreviewGenerator::m_captureFrame {-1}

protected

Definition at line 117 of file previewgenerator.h.

Referenced by RemotePreviewRun(), and Run().

◆ m_outFileName

QString PreviewGenerator::m_outFileName

protected

Definition at line 118 of file previewgenerator.h.

Referenced by IsLocal(), LocalPreviewRun(), RemotePreviewRun(), Run(), RunReal(), SaveOutFile(), and SetOutputFilename().

◆ m_outSize

QSize PreviewGenerator::m_outSize {0,0}

protected

Definition at line 119 of file previewgenerator.h.

Referenced by LocalPreviewRun(), RemotePreviewRun(), and Run().

◆ m_outFormat

QString PreviewGenerator::m_outFormat {"PNG"}

protected

Definition at line 120 of file previewgenerator.h.

Referenced by LocalPreviewRun(), and SetOutputFilename().

◆ m_token

QString PreviewGenerator::m_token

protected

Definition at line 122 of file previewgenerator.h.

Referenced by event(), RemotePreviewRun(), Run(), and RunReal().

◆ m_gotReply

bool PreviewGenerator::m_gotReply {false}

protected

Definition at line 123 of file previewgenerator.h.

Referenced by event(), and RemotePreviewRun().

◆ m_pixmapOk

bool PreviewGenerator::m_pixmapOk {false}

protected

Definition at line 124 of file previewgenerator.h.

Referenced by event(), and RemotePreviewRun().

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

mythtv/libs/libmythtv/previewgenerator.h
mythtv/libs/libmythtv/previewgenerator.cpp

Public Types

Public Slots

Public Member Functions

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Friends

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ Mode

Constructor & Destructor Documentation

◆ PreviewGenerator()

◆ ~PreviewGenerator()

Member Function Documentation

◆ SetPreviewTime()

◆ SetPreviewTimeAsSeconds()

◆ SetPreviewTimeAsFrameNumber()

◆ SetOutputFilename()

◆ SetOutputSize()

◆ GetToken()

◆ run()

◆ Run()

◆ AttachSignals()

◆ deleteLater

◆ TeardownAll()

◆ RemotePreviewRun()

◆ LocalPreviewRun()

◆ IsLocal()

◆ RunReal()

◆ GetScreenGrab()

◆ SavePreview()

◆ CreateAccessibleFilename()

◆ event()

◆ SaveOutFile()

Friends And Related Function Documentation

◆ preview_helper

Member Data Documentation

◆ m_previewWaitCondition

◆ m_previewLock

◆ m_programInfo

◆ m_mode

◆ m_listener

◆ m_pathname

◆ m_captureTime

◆ m_captureFrame

◆ m_outFileName

◆ m_outSize

◆ m_outFormat

◆ m_token

◆ m_gotReply

◆ m_pixmapOk