MediaCodec.LinearBlock
public
static
final
class
MediaCodec.LinearBlock
extends Object
java.lang.Object | |
↳ | android.media.MediaCodec.LinearBlock |
Section of memory that represents a linear block. Applications may
acquire a block via LinearBlock#obtain
and queue all or part
of the block as an input buffer to a codec, or get a block allocated by
codec as an output buffer from OutputFrame
.
See also:
Summary
Public methods | |
---|---|
static
boolean
|
isCodecCopyFreeCompatible(String[] codecNames)
Returns true if it is possible to allocate a linear block that can be passed to all listed codecs as input buffers without copying the content. |
boolean
|
isMappable()
Returns true if the buffer is mappable. |
ByteBuffer
|
map()
Map the memory and return the mapped region. |
static
MediaCodec.LinearBlock
|
obtain(int capacity, String[] codecNames)
Obtain a linear block object no smaller than |
void
|
recycle()
Mark this block as ready to be recycled by the framework once it is no longer in 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 | |
---|---|
Public methods
isCodecCopyFreeCompatible
public static boolean isCodecCopyFreeCompatible (String[] codecNames)
Returns true if it is possible to allocate a linear block that can be passed to all listed codecs as input buffers without copying the content.
Note that even if this function returns true, obtain(int, String)
may
still throw due to invalid arguments or allocation failure.
Parameters | |
---|---|
codecNames |
String : list of codecs that the client wants to use a
linear block without copying. Null entries are
ignored.
This value cannot be null . |
Returns | |
---|---|
boolean |
isMappable
public boolean isMappable ()
Returns true if the buffer is mappable.
Returns | |
---|---|
boolean |
Throws | |
---|---|
IllegalStateException |
if invalid |
map
public ByteBuffer map ()
Map the memory and return the mapped region.
The returned memory region becomes inaccessible after
recycle()
, or the buffer is queued to the codecs and not
returned to the client yet.
Returns | |
---|---|
ByteBuffer |
mapped memory region as ByteBuffer object
This value cannot be null . |
Throws | |
---|---|
IllegalStateException |
if not mappable or invalid |
obtain
public static MediaCodec.LinearBlock obtain (int capacity, String[] codecNames)
Obtain a linear block object no smaller than capacity
.
If isCodecCopyFreeCompatible(String)
with the same
codecNames
returned true, the returned
LinearBlock
object can be queued to the listed codecs without
copying. The returned LinearBlock
object is always
read/write mappable.
Parameters | |
---|---|
capacity |
int : requested capacity of the linear block in bytes |
codecNames |
String : list of codecs that the client wants to use this
linear block without copying. Null entries are
ignored.
This value cannot be null . |
Returns | |
---|---|
MediaCodec.LinearBlock |
a linear block object.
This value may be null . |
Throws | |
---|---|
IllegalArgumentException |
if the capacity is invalid or codecNames contains invalid name |
IOException |
if an error occurred while allocating a buffer |
recycle
public void recycle ()
Mark this block as ready to be recycled by the framework once it is no longer in use. All operations to this object after this call will cause exceptions, as well as attempt to access the previously mapped memory region. Caller should clear all references to this object after this call.
To avoid excessive memory consumption, it is recommended that callers recycle buffers as soon as they no longer need the buffers
Throws | |
---|---|
IllegalStateException |
if invalid |
Protected methods
finalize
protected 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 Java 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.