PreviewGenerator Class Reference

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

#include <previewgenerator.h>

Inheritance diagram for PreviewGenerator:

Public Types
enum	Mode { kNone = 0x0, kLocal = 0x1, kRemote = 0x2, kLocalAndRemote = 0x3, kForceLocal = 0x5, kModeMask = 0x7 }
typedef enum PreviewGenerator::Mode	Mode
Public Slots
void	deleteLater ()
Public Member Functions
	PreviewGenerator (const ProgramInfo *pginfo, const QString &token, Mode mode=kLocal)
	Constructor.
void	SetPreviewTime (long long time, bool in_seconds)
void	SetPreviewTimeAsSeconds (long long seconds_in)
void	SetPreviewTimeAsFrameNumber (long long frame_number)
void	SetOutputFilename (const QString &)
void	SetOutputSize (const QSize &size)
QString	GetToken (void) const
void	run (void)
	Runs the Qt event loop unless we have a QRunnable, in which case we run the runnable run instead.
bool	Run (void)
void	AttachSignals (QObject *)
Protected Member Functions
virtual	~PreviewGenerator ()
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.
virtual bool	event (QEvent *e)
bool	SaveOutFile (const QByteArray &data, const QDateTime &dt)
Static Protected Member Functions
static char *	GetScreenGrab (const ProgramInfo &pginfo, const QString &filename, long long seektime, bool time_in_secs, int &bufferlen, int &video_width, int &video_height, float &video_aspect)
	Returns a PIX_FMT_RGBA32 buffer containg a frame from the video.
static bool	SavePreview (QString filename, const unsigned char *data, uint width, uint height, float aspect, int desired_width, int desired_height)
static QString	CreateAccessibleFilename (const QString &pathname, const QString &outFileName)
Protected Attributes
QWaitCondition	previewWaitCondition
QMutex	previewLock
ProgramInfo	programInfo
Mode	mode
QObject *	listener
QString	pathname
bool	timeInSeconds
	tells us whether to use time as seconds or frame number
long long	captureTime
	snapshot time in seconds or frame number, depending on timeInSeconds
QString	outFileName
QSize	outSize
QString	token
bool	gotReply
bool	pixmapOk
Friends
int	preview_helper (uint chanid, QDateTime starttime, long long previewFrameNumber, long long previewSeconds, const QSize &previewSize, const QString &infile, const QString &outfile)

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 26 of file previewgenerator.h.

Member Typedef Documentation

typedef enum PreviewGenerator::Mode PreviewGenerator::Mode

Member Enumeration Documentation

enum PreviewGenerator::Mode

Enumerator:

kNone
kLocal
kRemote
kLocalAndRemote
kForceLocal
kModeMask

Definition at line 39 of file previewgenerator.h.

Constructor & Destructor Documentation

PreviewGenerator::PreviewGenerator	(	const ProgramInfo *	pginfo,
		const 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 'local_only' should be set to true, otherwise the backend may deadlock if the PreviewGenerator cannot find the file.

Parameters:

	pginfo	ProgramInfo for the recording we want a preview of.
	local_only	If set to true, the preview will only be generated if the file is local.

Definition at line 67 of file previewgenerator.cpp.

PreviewGenerator::~PreviewGenerator ( ) [protected, virtual]

Definition at line 78 of file previewgenerator.cpp.

Member Function Documentation

void PreviewGenerator::SetPreviewTime	(	long long	time,
		bool	in_seconds
	)			`[inline]`

Definition at line 54 of file previewgenerator.h.

Referenced by PreviewGeneratorQueue::GeneratePreviewImage().

void PreviewGenerator::SetPreviewTimeAsSeconds ( long long seconds_in ) [inline]

Definition at line 56 of file previewgenerator.h.

Referenced by Content::GetPreviewImage(), and preview_helper().

void PreviewGenerator::SetPreviewTimeAsFrameNumber ( long long frame_number ) [inline]

Definition at line 58 of file previewgenerator.h.

Referenced by preview_helper().

void PreviewGenerator::SetOutputFilename ( const QString & fileName )

Definition at line 84 of file previewgenerator.cpp.

Referenced by PreviewGeneratorQueue::GeneratePreviewImage(), Content::GetPreviewImage(), and preview_helper().

void PreviewGenerator::SetOutputSize ( const QSize & size ) [inline]

Definition at line 61 of file previewgenerator.h.

Referenced by PreviewGeneratorQueue::GeneratePreviewImage(), Content::GetPreviewImage(), and preview_helper().

QString PreviewGenerator::GetToken ( void ) const [inline]

Definition at line 63 of file previewgenerator.h.

Referenced by PreviewGeneratorQueue::SetPreviewGenerator().

void PreviewGenerator::run ( void ) [virtual]

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 327 of file previewgenerator.cpp.

bool PreviewGenerator::Run ( void )

Definition at line 192 of file previewgenerator.cpp.

Referenced by JobQueue::DoFlagCommercialsThread(), Content::GetPreviewImage(), and run().

void PreviewGenerator::AttachSignals ( QObject * obj )

Definition at line 102 of file previewgenerator.cpp.

Referenced by PreviewGeneratorQueue::SetPreviewGenerator().

void PreviewGenerator::deleteLater ( void ) [slot]

Definition at line 96 of file previewgenerator.cpp.

Referenced by JobQueue::DoFlagCommercialsThread(), Content::GetPreviewImage(), preview_helper(), and PreviewGeneratorQueue::SetPreviewGenerator().

void PreviewGenerator::TeardownAll ( void ) [protected]

Definition at line 89 of file previewgenerator.cpp.

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

bool PreviewGenerator::RemotePreviewRun ( void ) [protected]

Definition at line 334 of file previewgenerator.cpp.

Referenced by Run(), and RunReal().

bool PreviewGenerator::LocalPreviewRun ( void ) [protected]

Definition at line 600 of file previewgenerator.cpp.

Referenced by RunReal().

bool PreviewGenerator::IsLocal ( void ) const [protected]

Definition at line 719 of file previewgenerator.cpp.

Referenced by Run(), and RunReal().

bool PreviewGenerator::RunReal ( void ) [protected]

This call creates a preview without starting a new thread.

Definition at line 111 of file previewgenerator.cpp.

Referenced by preview_helper().

char * PreviewGenerator::GetScreenGrab	(	const ProgramInfo &	pginfo,
		const QString &	filename,
		long long	seektime,
		bool	time_in_secs,
		int &	bufferlen,
		int &	video_width,
		int &	video_height,
		float &	video_aspect
	)			`[static, protected]`

Returns a PIX_FMT_RGBA32 buffer containg a frame from the video.

Parameters:

	pginfo	Recording to grab from.
	filename	File containing recording.
	seektime	Seconds or frames into the video to seek before capturing a frame.
	time_in_secs	if true time is in seconds, otherwise it is in frames.
	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, NULL otherwise.

Definition at line 757 of file previewgenerator.cpp.

Referenced by LocalPreviewRun().

bool PreviewGenerator::SavePreview	(	QString	filename,
		const unsigned char *	data,
		uint	width,
		uint	height,
		float	aspect,
		int	desired_width,
		int	desired_height
	)			`[static, protected]`

Definition at line 531 of file previewgenerator.cpp.

Referenced by LocalPreviewRun().

QString PreviewGenerator::CreateAccessibleFilename	(	const QString &	pathname,
		const QString &	outFileName
	)			`[static, protected]`

Definition at line 688 of file previewgenerator.cpp.

Referenced by LocalPreviewRun().

bool PreviewGenerator::event ( QEvent * e ) [protected, virtual]

Definition at line 395 of file previewgenerator.cpp.

bool PreviewGenerator::SaveOutFile	(	const QByteArray &	data,
		const QDateTime &	dt
	)			`[protected]`

Definition at line 466 of file previewgenerator.cpp.

Referenced by event().

Friends And Related Function Documentation

int preview_helper	(	uint	chanid,
		QDateTime	starttime,
		long long	previewFrameNumber,
		long long	previewSeconds,
		const QSize &	previewSize,
		const QString &	infile,
		const QString &	outfile
	)			`[friend]`