org.mycore.datamodel.ifs
Class MCRAudioVideoExtender

java.lang.Object
  org.mycore.datamodel.ifs.MCRAudioVideoExtender

Direct Known Subclasses:

MCRAVExtRealHelix, MCRAVExtVideoCharger

public abstract class MCRAudioVideoExtender
extends Object

For MCRFiles that contain streaming audio/video, instances of this class provide methods to get technical metadata like bitrate, framerate, duration, size etc. and to start a player to stream the asset to a browser.

Version:

$Revision: 15022 $ $Date: 2009-03-26 14:53:00 +0100 (Thu, 26 Mar 2009) $

Author:

Frank Lützenkirchen

Field Summary

static boolean	AUDIO Constant for media type = audio
protected String	baseMetadata The base URL of a cgi that provides technical metadata about the asset
protected String	basePlayerStarter The base URL where to get a metafile that starts a player in browser
protected int	bitRate The bitrate of the asset in number of bits per second
protected String	contentTypeID The content type of the asset
protected int	durationHours The hours part of the duration of the asset
protected int	durationMinutes The minutes part of the duration of the asset
protected int	durationSeconds The seconds part of the duration of the asset
protected MCRFileReader	file The asset file this extender belongs to
protected double	frameRate The framerate of the asset in number of frames per second
protected boolean	mediaType The media type of the asset, either AUDIO or VIDEO
protected String	playerDownloadURL The URL where clients can download a player for the asset
protected String	playerStarterCT The MIME type a servlet has to send with the player starter
protected long	size The size of the asset in bytes
static boolean	VIDEO Constant for media type = video

Constructor Summary

MCRAudioVideoExtender()
Creates a new MCRAudioVideoExtender.

Method Summary

protected void	forwardData(URLConnection connection, OutputStream out) Helper method that reads all data from an URLConnection input stream and forwards it to the given output stream.
protected String	getBetween(String prefix, String suffix, String data, String defaultValue) Helper method to get a substring that lies between a prefix and a suffix string.
int	getBitRate() Returns the maximum number of bits per seconds when asset is streamed
String	getBitRateFormatted() Returns the streaming bitrate formatted as a String, e.
protected URLConnection	getConnection(String url) Helper method that creates a URLConnection to a given URL and wraps possible IOException or MalformedURLExceptions
protected int	getConnectTimeout()
String	getContentTypeID() Returns the ID of the content type of this asset
String	getDurationFormatted(String hourLabel, String minutesLabel, String secondsLabel) Returns the duration of this asset, formatted as a String for output.
int	getDurationHours() Returns the hours part of the duration of this asset
int	getDurationMinutes() Returns the minutes part of the duration of this asset
int	getDurationSeconds() Returns the seconds part of the duration of this asset
String	getDurationTimecode() Returns the duration of the asset, formatted as a timcode, e.
double	getFrameRate() Returns the maximum number of frames per second for a streaming video asset
String	getFrameRateFormatted() Returns the framerate formatted as a String, e.
boolean	getMediaType() Returns the media type, either AUDIO od VIDEO for this asset
protected String	getMetadata(String url) Helper method that connects to the given URL and returns the response as a String
String	getPlayerDownloadURL() Returns the URL where clients can download a player for this asset
String	getPlayerStarterContentType() Returns the MIME type a servlet has to set in the HTTP response that delivers the player starter metafile to the browser
abstract void	getPlayerStarterTo(OutputStream out, String startPos, String stopPos) Writes a metafile that starts a streaming player for this asset to an OutputStream, e.
long	getSize() Returns the asset size in number of bytes.
String	getSizeFormatted() Returns the asset size, formatted as a String.
void	init(MCRFileReader file) Initializes this AudioVideoExtender and gets technical metadata from the server that holds the streaming asset.
boolean	isAudio() Returns true, if this asset is an audio asset.
boolean	isVideo() Returns true, if this asset is a video asset.
String	toString() Returns a string representation of this extender's data, useful for debugging.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

VIDEO

public static final boolean VIDEO

Constant for media type = video

See Also:

Constant Field Values

AUDIO

public static final boolean AUDIO

Constant for media type = audio

See Also:

Constant Field Values

bitRate

protected int bitRate

The bitrate of the asset in number of bits per second

frameRate

protected double frameRate

The framerate of the asset in number of frames per second

mediaType

protected boolean mediaType

The media type of the asset, either AUDIO or VIDEO

durationHours

protected int durationHours

The hours part of the duration of the asset

durationMinutes

protected int durationMinutes

The minutes part of the duration of the asset

durationSeconds

protected int durationSeconds

The seconds part of the duration of the asset

size

protected long size

The size of the asset in bytes

contentTypeID

protected String contentTypeID

The content type of the asset

playerDownloadURL

protected String playerDownloadURL

The URL where clients can download a player for the asset

playerStarterCT

protected String playerStarterCT

The MIME type a servlet has to send with the player starter

basePlayerStarter

protected String basePlayerStarter

The base URL where to get a metafile that starts a player in browser

baseMetadata

protected String baseMetadata

The base URL of a cgi that provides technical metadata about the asset

file

protected MCRFileReader file

The asset file this extender belongs to

Constructor Detail

MCRAudioVideoExtender

public MCRAudioVideoExtender()

Creates a new MCRAudioVideoExtender. The instance has to be initialized by invoking init() before it can be used.

Method Detail

init

public void init(MCRFileReader file)
          throws MCRException

Initializes this AudioVideoExtender and gets technical metadata from the server that holds the streaming asset. Subclasses must override this method!

Parameters:

file - the MCRFile that this extender belongs to

Throws:

MCRException

getBitRate

public int getBitRate()

Returns the maximum number of bits per seconds when asset is streamed

Returns:

the maximum number of bits per seconds when asset is streamed

getBitRateFormatted

public String getBitRateFormatted()

Returns the streaming bitrate formatted as a String, e. g. "1.3 MBit" or "300 kBit".

Returns:

the streaming bitrate formatted as a String

getFrameRate

public double getFrameRate()

Returns the maximum number of frames per second for a streaming video asset

Returns:

the maximum number of frames per second for a streaming video asset

getFrameRateFormatted

public String getFrameRateFormatted()

Returns the framerate formatted as a String, e. g. "25.0"

Returns:

the framerate formatted as a String, e. g. "25.0"

getMediaType

public boolean getMediaType()

Returns the media type, either AUDIO od VIDEO for this asset

Returns:

the media type, compare to the boolean constants in this class

isAudio

public boolean isAudio()

Returns true, if this asset is an audio asset.

Returns:

true, if this asset is an audio asset.

isVideo

public boolean isVideo()

Returns true, if this asset is a video asset.

Returns:

true, if this asset is a video asset.

getDurationHours

public int getDurationHours()

Returns the hours part of the duration of this asset

Returns:

the hours part of the duration of this asset

getDurationMinutes

public int getDurationMinutes()

Returns the minutes part of the duration of this asset

Returns:

the minutes part of the duration of this asset

getDurationSeconds

public int getDurationSeconds()

Returns the seconds part of the duration of this asset

Returns:

the seconds part of the duration of this asset

getDurationFormatted

public String getDurationFormatted(String hourLabel,
                                   String minutesLabel,
                                   String secondsLabel)

Returns the duration of this asset, formatted as a String for output. For example, getDurationFormatted( "Std.", "Min.", "Sek." ) will return the String "1 Std. 15 Min." for an asset that is one hour and 15 minutes long. If duration is less than one hour, only minutes and seconds go into the output string, otherwise hours and minutes are used.

Parameters:

hourLabel - the label for the hours part of the duration

minutesLabel - the label for the minutes part of the duration

secondsLabel - the label for the seconds part of the duration

Returns:

the duration of this asset, formatted as a String

getDurationTimecode

public String getDurationTimecode()

Returns the duration of the asset, formatted as a timcode, e. g. "01:15:00" for an asset thats duration is one hour and 15 minutes.

Returns:

the duration foramatted as a timecode like "hh:mm:ss"

getSize

public long getSize()

Returns the asset size in number of bytes.

Returns:

the asset size in number of bytes

getSizeFormatted

public String getSizeFormatted()

Returns the asset size, formatted as a String.

Returns:

the asset size, formatted as a String

getContentTypeID

public String getContentTypeID()

Returns the ID of the content type of this asset

Returns:

the ID of the content type of this asset

getPlayerDownloadURL

public String getPlayerDownloadURL()

Returns the URL where clients can download a player for this asset

Returns:

the URL where clients can download a player for this asset

getPlayerStarterTo

public abstract void getPlayerStarterTo(OutputStream out,
                                        String startPos,
                                        String stopPos)
                                 throws MCRPersistenceException

Writes a metafile that starts a streaming player for this asset to an OutputStream, e. g. a ServletOutputStream. The browser then streams the asset. The client may provide a start and stop position to play only a certain part of the asset.

Parameters:

out - the OutputStream to write the player starter to

startPos - the optional start position in the format "hh:mm:ss"

stopPos - the optional stop position in the format "hh:mm:ss"

Throws:

MCRPersistenceException

getPlayerStarterContentType

public String getPlayerStarterContentType()

Returns the MIME type a servlet has to set in the HTTP response that delivers the player starter metafile to the browser

Returns:

the MIME type of the player starter metafile

toString

public String toString()

Returns a string representation of this extender's data, useful for debugging.

Overrides:

toString in class Object

Returns:

a String containing useful information about this extender's data

getBetween

protected String getBetween(String prefix,
                            String suffix,
                            String data,
                            String defaultValue)

Helper method to get a substring that lies between a prefix and a suffix string. If either prefix or suffix are not found in the string, the defaultValue is returned. This helper method is used by subclasses to parse metadata that is read from the server.

Parameters:

prefix - the string before the substring

suffix - the string after the substring

data - the string to search through

defaultValue - the default to return when no match is found

Returns:

the substring between prefix and suffix

forwardData

protected void forwardData(URLConnection connection,
                           OutputStream out)
                    throws IOException

Helper method that reads all data from an URLConnection input stream and forwards it to the given output stream.

Parameters:

connection - the URLConnection to get the InputStream from

out - the OutputStream to write the bytes to

Throws:

IOException

getConnection

protected URLConnection getConnection(String url)
                               throws MCRPersistenceException

Helper method that creates a URLConnection to a given URL and wraps possible IOException or MalformedURLExceptions

Parameters:

url - the URL to connect to

Throws:

MCRPersistenceException

getMetadata

protected String getMetadata(String url)
                      throws MCRPersistenceException

Helper method that connects to the given URL and returns the response as a String

Parameters:

url - the URL to connect to

Returns:

the response content as a String

Throws:

MCRPersistenceException

getConnectTimeout

protected int getConnectTimeout()