public
class
MediaMetadataRetriever
extends Object
java.lang.Object | |
↳ | android.media.MediaMetadataRetriever |
MediaMetadataRetriever class provides a unified interface for retrieving frame and meta data from an input media file.
Constants | |
---|---|
int |
METADATA_KEY_ALBUM
The metadata key to retrieve the information about the album title of the data source. |
int |
METADATA_KEY_ALBUMARTIST
The metadata key to retrieve the information about the performers or artist associated with the data source. |
int |
METADATA_KEY_ARTIST
The metadata key to retrieve the information about the artist of the data source. |
int |
METADATA_KEY_AUTHOR
The metadata key to retrieve the information about the author of the data source. |
int |
METADATA_KEY_BITRATE
This key retrieves the average bitrate (in bits/sec), if available. |
int |
METADATA_KEY_CAPTURE_FRAMERATE
This key retrieves the original capture framerate, if it's available. |
int |
METADATA_KEY_CD_TRACK_NUMBER
The metadata key to retrieve the numeric string describing the order of the audio data source on its original recording. |
int |
METADATA_KEY_COMPILATION
The metadata key to retrieve the music album compilation status. |
int |
METADATA_KEY_COMPOSER
The metadata key to retrieve the information about the composer of the data source. |
int |
METADATA_KEY_DATE
The metadata key to retrieve the date when the data source was created or modified. |
int |
METADATA_KEY_DISC_NUMBER
The metadata key to retrieve the numberic string that describes which part of a set the audio data source comes from. |
int |
METADATA_KEY_DURATION
The metadata key to retrieve the playback duration of the data source. |
int |
METADATA_KEY_GENRE
The metadata key to retrieve the content type or genre of the data source. |
int |
METADATA_KEY_HAS_AUDIO
If this key exists the media contains audio content. |
int |
METADATA_KEY_HAS_VIDEO
If this key exists the media contains video content. |
int |
METADATA_KEY_LOCATION
This key retrieves the location information, if available. |
int |
METADATA_KEY_MIMETYPE
The metadata key to retrieve the mime type of the data source. |
int |
METADATA_KEY_NUM_TRACKS
The metadata key to retrieve the number of tracks, such as audio, video, text, in the data source, such as a mp4 or 3gpp file. |
int |
METADATA_KEY_TITLE
The metadata key to retrieve the data source title. |
int |
METADATA_KEY_VIDEO_HEIGHT
If the media contains video, this key retrieves its height. |
int |
METADATA_KEY_VIDEO_ROTATION
This key retrieves the video rotation angle in degrees, if available. |
int |
METADATA_KEY_VIDEO_WIDTH
If the media contains video, this key retrieves its width. |
int |
METADATA_KEY_WRITER
The metadata key to retrieve the information of the writer (such as lyricist) of the data source. |
int |
METADATA_KEY_YEAR
The metadata key to retrieve the year when the data source was created or modified. |
int |
OPTION_CLOSEST
This option is used with |
int |
OPTION_CLOSEST_SYNC
This option is used with |
int |
OPTION_NEXT_SYNC
This option is used with |
int |
OPTION_PREVIOUS_SYNC
This option is used with |
Public constructors | |
---|---|
MediaMetadataRetriever()
|
Public methods | |
---|---|
String
|
extractMetadata(int keyCode)
Call this method after setDataSource(). |
byte[]
|
getEmbeddedPicture()
Call this method after setDataSource(). |
Bitmap
|
getFrameAtTime(long timeUs)
Call this method after setDataSource(). |
Bitmap
|
getFrameAtTime()
Call this method after setDataSource(). |
Bitmap
|
getFrameAtTime(long timeUs, int option)
Call this method after setDataSource(). |
void
|
release()
Call it when one is done with the object. |
void
|
setDataSource(FileDescriptor fd, long offset, long length)
Sets the data source (FileDescriptor) to use. |
void
|
setDataSource(String path)
Sets the data source (file pathname) to use. |
void
|
setDataSource(Context context, Uri uri)
Sets the data source as a content Uri. |
void
|
setDataSource(FileDescriptor fd)
Sets the data source (FileDescriptor) to use. |
void
|
setDataSource(String uri, Map<String, String> headers)
Sets the data source (URI) to use. |
void
|
setDataSource(MediaDataSource dataSource)
Sets the data source (MediaDataSource) to use. |
Protected methods | |
---|---|
void
|
finalize()
Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. |
Inherited methods | |
---|---|
From
class
java.lang.Object
|
int METADATA_KEY_ALBUM
The metadata key to retrieve the information about the album title of the data source.
Constant Value: 1 (0x00000001)
int METADATA_KEY_ALBUMARTIST
The metadata key to retrieve the information about the performers or artist associated with the data source.
Constant Value: 13 (0x0000000d)
int METADATA_KEY_ARTIST
The metadata key to retrieve the information about the artist of the data source.
Constant Value: 2 (0x00000002)
int METADATA_KEY_AUTHOR
The metadata key to retrieve the information about the author of the data source.
Constant Value: 3 (0x00000003)
int METADATA_KEY_BITRATE
This key retrieves the average bitrate (in bits/sec), if available.
Constant Value: 20 (0x00000014)
int METADATA_KEY_CAPTURE_FRAMERATE
This key retrieves the original capture framerate, if it's available. The capture framerate will be a floating point number.
Constant Value: 25 (0x00000019)
int METADATA_KEY_CD_TRACK_NUMBER
The metadata key to retrieve the numeric string describing the order of the audio data source on its original recording.
Constant Value: 0 (0x00000000)
int METADATA_KEY_COMPILATION
The metadata key to retrieve the music album compilation status.
Constant Value: 15 (0x0000000f)
int METADATA_KEY_COMPOSER
The metadata key to retrieve the information about the composer of the data source.
Constant Value: 4 (0x00000004)
int METADATA_KEY_DATE
The metadata key to retrieve the date when the data source was created or modified.
Constant Value: 5 (0x00000005)
int METADATA_KEY_DISC_NUMBER
The metadata key to retrieve the numberic string that describes which part of a set the audio data source comes from.
Constant Value: 14 (0x0000000e)
int METADATA_KEY_DURATION
The metadata key to retrieve the playback duration of the data source.
Constant Value: 9 (0x00000009)
int METADATA_KEY_GENRE
The metadata key to retrieve the content type or genre of the data source.
Constant Value: 6 (0x00000006)
int METADATA_KEY_HAS_AUDIO
If this key exists the media contains audio content.
Constant Value: 16 (0x00000010)
int METADATA_KEY_HAS_VIDEO
If this key exists the media contains video content.
Constant Value: 17 (0x00000011)
int METADATA_KEY_LOCATION
This key retrieves the location information, if available. The location should be specified according to ISO-6709 standard, under a mp4/3gp box "@xyz". Location with longitude of -90 degrees and latitude of 180 degrees will be retrieved as "-90.0000+180.0000", for instance.
Constant Value: 23 (0x00000017)
int METADATA_KEY_MIMETYPE
The metadata key to retrieve the mime type of the data source. Some example mime types include: "video/mp4", "audio/mp4", "audio/amr-wb", etc.
Constant Value: 12 (0x0000000c)
int METADATA_KEY_NUM_TRACKS
The metadata key to retrieve the number of tracks, such as audio, video, text, in the data source, such as a mp4 or 3gpp file.
Constant Value: 10 (0x0000000a)
int METADATA_KEY_TITLE
The metadata key to retrieve the data source title.
Constant Value: 7 (0x00000007)
int METADATA_KEY_VIDEO_HEIGHT
If the media contains video, this key retrieves its height.
Constant Value: 19 (0x00000013)
int METADATA_KEY_VIDEO_ROTATION
This key retrieves the video rotation angle in degrees, if available. The video rotation angle may be 0, 90, 180, or 270 degrees.
Constant Value: 24 (0x00000018)
int METADATA_KEY_VIDEO_WIDTH
If the media contains video, this key retrieves its width.
Constant Value: 18 (0x00000012)
int METADATA_KEY_WRITER
The metadata key to retrieve the information of the writer (such as lyricist) of the data source.
Constant Value: 11 (0x0000000b)
int METADATA_KEY_YEAR
The metadata key to retrieve the year when the data source was created or modified.
Constant Value: 8 (0x00000008)
int OPTION_CLOSEST
This option is used with getFrameAtTime(long, int)
to retrieve
a frame (not necessarily a key frame) associated with a data source that
is located closest to or at the given time.
See also:
Constant Value: 3 (0x00000003)
int OPTION_CLOSEST_SYNC
This option is used with getFrameAtTime(long, int)
to retrieve
a sync (or key) frame associated with a data source that is located
closest to (in time) or at the given time.
See also:
Constant Value: 2 (0x00000002)
int OPTION_NEXT_SYNC
This option is used with getFrameAtTime(long, int)
to retrieve
a sync (or key) frame associated with a data source that is located
right after or at the given time.
See also:
Constant Value: 1 (0x00000001)
int OPTION_PREVIOUS_SYNC
This option is used with getFrameAtTime(long, int)
to retrieve
a sync (or key) frame associated with a data source that is located
right before or at the given time.
See also:
Constant Value: 0 (0x00000000)
String extractMetadata (int keyCode)
Call this method after setDataSource(). This method retrieves the meta data value associated with the keyCode. The keyCode currently supported is listed below as METADATA_XXX constants. With any other value, it returns a null pointer.
Parameters | |
---|---|
keyCode |
int :
One of the constants listed below at the end of the class. |
Returns | |
---|---|
String |
The meta data value associate with the given keyCode on success; null on failure. |
byte[] getEmbeddedPicture ()
Call this method after setDataSource(). This method finds the optional graphic or album/cover art associated associated with the data source. If there are more than one pictures, (any) one of them is returned.
Returns | |
---|---|
byte[] |
null if no such graphic is found. |
Bitmap getFrameAtTime (long timeUs)
Call this method after setDataSource(). This method finds a
representative frame close to the given time position if possible,
and returns it as a bitmap. This is useful for generating a thumbnail
for an input data source. Call this method if one does not care
how the frame is found as long as it is close to the given time;
otherwise, please call getFrameAtTime(long, int)
.
Parameters | |
---|---|
timeUs |
long :
The time position where the frame will be retrieved.
When retrieving the frame at the given time position, there is no
guarentee that the data source has a frame located at the position.
When this happens, a frame nearby will be returned. If timeUs is
negative, time position and option will ignored, and any frame
that the implementation considers as representative may be returned. |
Returns | |
---|---|
Bitmap |
A Bitmap containing a representative video frame, which can be null, if such a frame cannot be retrieved. |
See also:
Bitmap getFrameAtTime ()
Call this method after setDataSource(). This method finds a
representative frame at any time position if possible,
and returns it as a bitmap. This is useful for generating a thumbnail
for an input data source. Call this method if one does not
care about where the frame is located; otherwise, please call
getFrameAtTime(long)
or getFrameAtTime(long, int)
Returns | |
---|---|
Bitmap |
A Bitmap containing a representative video frame, which can be null, if such a frame cannot be retrieved. |
Bitmap getFrameAtTime (long timeUs, int option)
Call this method after setDataSource(). This method finds a representative frame close to the given time position by considering the given option if possible, and returns it as a bitmap. This is useful for generating a thumbnail for an input data source or just obtain and display a frame at the given time position.
Parameters | |
---|---|
timeUs |
long :
The time position where the frame will be retrieved.
When retrieving the frame at the given time position, there is no
guarantee that the data source has a frame located at the position.
When this happens, a frame nearby will be returned. If timeUs is
negative, time position and option will ignored, and any frame
that the implementation considers as representative may be returned. |
option |
int :
a hint on how the frame is found. Use
OPTION_PREVIOUS_SYNC if one wants to retrieve a sync frame
that has a timestamp earlier than or the same as timeUs. Use
OPTION_NEXT_SYNC if one wants to retrieve a sync frame
that has a timestamp later than or the same as timeUs. Use
OPTION_CLOSEST_SYNC if one wants to retrieve a sync frame
that has a timestamp closest to or the same as timeUs. Use
OPTION_CLOSEST if one wants to retrieve a frame that may
or may not be a sync frame but is closest to or the same as timeUs.
OPTION_CLOSEST often has larger performance overhead compared
to the other options if there is no sync frame located at timeUs. |
Returns | |
---|---|
Bitmap |
A Bitmap containing a representative video frame, which can be null, if such a frame cannot be retrieved. |
void release ()
Call it when one is done with the object. This method releases the memory allocated internally.
void setDataSource (FileDescriptor fd, long offset, long length)
Sets the data source (FileDescriptor) to use. It is the caller's responsibility to close the file descriptor. It is safe to do so as soon as this call returns. Call this method before the rest of the methods in this class. This method may be time-consuming.
Parameters | |
---|---|
fd |
FileDescriptor :
the FileDescriptor for the file you want to play |
offset |
long :
the offset into the file where the data to be played starts,
in bytes. It must be non-negative |
length |
long :
the length in bytes of the data to be played. It must be
non-negative. |
Throws | |
---|---|
IllegalArgumentException |
if the arguments are invalid |
void setDataSource (String path)
Sets the data source (file pathname) to use. Call this method before the rest of the methods in this class. This method may be time-consuming.
Parameters | |
---|---|
path |
String :
The path of the input media file. |
Throws | |
---|---|
IllegalArgumentException |
If the path is invalid. |
void setDataSource (Context context, Uri uri)
Sets the data source as a content Uri. Call this method before the rest of the methods in this class. This method may be time-consuming.
Parameters | |
---|---|
context |
Context :
the Context to use when resolving the Uri |
uri |
Uri :
the Content URI of the data you want to play |
Throws | |
---|---|
IllegalArgumentException |
if the Uri is invalid |
SecurityException |
if the Uri cannot be used due to lack of permission. |
void setDataSource (FileDescriptor fd)
Sets the data source (FileDescriptor) to use. It is the caller's responsibility to close the file descriptor. It is safe to do so as soon as this call returns. Call this method before the rest of the methods in this class. This method may be time-consuming.
Parameters | |
---|---|
fd |
FileDescriptor :
the FileDescriptor for the file you want to play |
Throws | |
---|---|
IllegalArgumentException |
if the FileDescriptor is invalid |
void setDataSource (String uri, Map<String, String> headers)
Sets the data source (URI) to use. Call this method before the rest of the methods in this class. This method may be time-consuming.
Parameters | |
---|---|
uri |
String :
The URI of the input media. |
headers |
Map :
the headers to be sent together with the request for the data |
Throws | |
---|---|
IllegalArgumentException |
If the URI is invalid. |
void setDataSource (MediaDataSource dataSource)
Sets the data source (MediaDataSource) to use.
Parameters | |
---|---|
dataSource |
MediaDataSource :
the MediaDataSource for the media you want to play
|
Throws | |
---|---|
IllegalArgumentException |
void finalize ()
Called by the garbage collector on an object when garbage collection
determines that there are no more references to the object.
A subclass overrides the finalize
method to dispose of
system resources or to perform other cleanup.
The general contract of finalize
is that it is invoked
if and when the JavaTM virtual
machine has determined that there is no longer any
means by which this object can be accessed by any thread that has
not yet died, except as a result of an action taken by the
finalization of some other object or class which is ready to be
finalized. The finalize
method may take any action, including
making this object available again to other threads; the usual purpose
of finalize
, however, is to perform cleanup actions before
the object is irrevocably discarded. For example, the finalize method
for an object that represents an input/output connection might perform
explicit I/O transactions to break the connection before the object is
permanently discarded.
The finalize
method of class Object
performs no
special action; it simply returns normally. Subclasses of
Object
may override this definition.
The Java programming language does not guarantee which thread will
invoke the finalize
method for any given object. It is
guaranteed, however, that the thread that invokes finalize will not
be holding any user-visible synchronization locks when finalize is
invoked. If an uncaught exception is thrown by the finalize method,
the exception is ignored and finalization of that object terminates.
After the finalize
method has been invoked for an object, no
further action is taken until the Java virtual machine has again
determined that there is no longer any means by which this object can
be accessed by any thread that has not yet died, including possible
actions by other objects or classes which are ready to be finalized,
at which point the object may be discarded.
The finalize
method is never invoked more than once by a Java
virtual machine for any given object.
Any exception thrown by the finalize
method causes
the finalization of this object to be halted, but is otherwise
ignored.
Throws | |
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Throwable |