org.jitsi.impl.neomedia.codec.video.vp8

Class DePacketizer.VP8PayloadDescriptor

java.lang.Object

org.jitsi.impl.neomedia.codec.video.vp8.DePacketizer.VP8PayloadDescriptor

Enclosing class:

DePacketizer

public static class DePacketizer.VP8PayloadDescriptor
extends Object

A class that represents the VP8 Payload Descriptor structure defined in draft-ietf-payload-vp8-10

Field Summary

Fields

Modifier and Type	Field and Description
static int	EXTENDED_PICTURE_ID_MASK The bitmask for the extended picture id field.
static int	MAX_LENGTH Maximum length of a VP8 Payload Descriptor.
static int	TL0PICIDX_MASK The bitmask for the TL0PICIDX field.

Constructor Summary

Constructors

Constructor and Description
VP8PayloadDescriptor()

Method Summary

Modifier and Type	Method and Description
static byte[]	create(boolean startOfPartition) Returns a simple Payload Descriptor, with PartID = 0, the 'start of partition' bit set according to startOfPartition, and all other bits set to 0.
static int	getPartitionId(byte[] input, int offset) Returns the value of the PID (partition ID) field of the VP8 Payload Descriptor at offset offset in input.
static int	getPictureId(byte[] input, int offset) Gets the value of the PictureID field of a VP8 Payload Descriptor.
static int	getSize(byte[] input, int offset, int length) The size in bytes of the Payload Descriptor at offset offset in input.
static int	getSize(org.jitsi.utils.ByteArrayBuffer baf) The size in bytes of the Payload Descriptor at offset offset in input.
static int	getTemporalLayerIndex(byte[] buf, int off, int len) Gets the temporal layer index (TID), if that's set.
static int	getTL0PICIDX(byte[] buf, int off, int len) Gets the TL0PICIDX from the payload descriptor.
static boolean	hasExtendedPictureId(byte[] buf, int off, int len) Determines whether the VP8 payload specified in the buffer that is passed as an argument has an extended picture ID or not.
static boolean	hasPictureId(byte[] buf, int off, int len) Determines whether the VP8 payload specified in the buffer that is passed as an argument has a picture ID or not.
static boolean	isReference(byte[] buf, int off, int len) Gets a boolean that indicates whether or not the non-reference bit is set.
static boolean	isStartOfFrame(byte[] input, int offset) Returns true if both the 'start of partition' bit is set and the PID fields has value 0 in the VP8 Payload Descriptor at offset offset in input.
static boolean	isStartOfPartition(byte[] input, int offset) Checks whether the 'start of partition' bit is set in the VP8 Payload Descriptor at offset offset in input.
static boolean	isValid(byte[] buf, int off, int len) Checks whether the arguments specify a valid buffer.
static boolean	setExtendedPictureId(byte[] buf, int off, int len, int val) Sets the extended picture ID for the VP8 payload specified in the buffer that is passed as an argument.
static boolean	setTL0PICIDX(byte[] buf, int off, int len, int val) Sets the TL0PICIDX field for the VP8 payload specified in the buffer that is passed as an argument.
static String	toString(byte[] buf, int off, int len) Provides a string description of the VP8 descriptor that can be used for debugging purposes.

Methods inherited from class java.lang.Object

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

Field Detail

TL0PICIDX_MASK

public static final int TL0PICIDX_MASK

The bitmask for the TL0PICIDX field.

See Also:

Constant Field Values

EXTENDED_PICTURE_ID_MASK

public static final int EXTENDED_PICTURE_ID_MASK

The bitmask for the extended picture id field.

See Also:

Constant Field Values

MAX_LENGTH

public static final int MAX_LENGTH

Maximum length of a VP8 Payload Descriptor.

See Also:

Constant Field Values

Constructor Detail

VP8PayloadDescriptor

public VP8PayloadDescriptor()

Method Detail

getTemporalLayerIndex

public static int getTemporalLayerIndex(byte[] buf,
                                        int off,
                                        int len)

Gets the temporal layer index (TID), if that's set.

Parameters:

buf - the byte buffer that holds the VP8 packet.

off - the offset in the byte buffer where the VP8 packet starts.

len - the length of the VP8 packet.

Returns:

the temporal layer index (TID), if that's set, -1 otherwise.

create

public static byte[] create(boolean startOfPartition)

Returns a simple Payload Descriptor, with PartID = 0, the 'start of partition' bit set according to startOfPartition, and all other bits set to 0.

Parameters:

startOfPartition - whether to 'start of partition' bit should be set

Returns:

a simple Payload Descriptor, with PartID = 0, the 'start of partition' bit set according to startOfPartition, and all other bits set to 0.

getSize

public static int getSize(org.jitsi.utils.ByteArrayBuffer baf)

The size in bytes of the Payload Descriptor at offset offset in input. The size is between 1 and 6.

Parameters:

baf - the ByteArrayBuffer that holds the VP8 payload descriptor.

Returns:

The size in bytes of the Payload Descriptor at offset offset in input, or -1 if the input is not a valid VP8 Payload Descriptor. The size is between 1 and 6.

getSize

public static int getSize(byte[] input,
                          int offset,
                          int length)

The size in bytes of the Payload Descriptor at offset offset in input. The size is between 1 and 6.

Parameters:

input - input

offset - offset

length - length

Returns:

The size in bytes of the Payload Descriptor at offset offset in input, or -1 if the input is not a valid VP8 Payload Descriptor. The size is between 1 and 6.

hasPictureId

public static boolean hasPictureId(byte[] buf,
                                   int off,
                                   int len)

Determines whether the VP8 payload specified in the buffer that is passed as an argument has a picture ID or not.

Parameters:

buf - the byte buffer that contains the VP8 payload.

off - the offset in the byte buffer where the VP8 payload starts.

len - the length of the VP8 payload in the byte buffer.

Returns:

true if the VP8 payload contains a picture ID, false otherwise.

hasExtendedPictureId

public static boolean hasExtendedPictureId(byte[] buf,
                                           int off,
                                           int len)

Determines whether the VP8 payload specified in the buffer that is passed as an argument has an extended picture ID or not.

Parameters:

buf - the byte buffer that contains the VP8 payload.

off - the offset in the byte buffer where the VP8 payload starts.

len - the length of the VP8 payload in the byte buffer.

Returns:

true if the VP8 payload contains an extended picture ID, false otherwise.

getPictureId

public static int getPictureId(byte[] input,
                               int offset)

Gets the value of the PictureID field of a VP8 Payload Descriptor.

Parameters:

input -

offset -

Returns:

the value of the PictureID field of a VP8 Payload Descriptor, or -1 if the fields is not present.

setExtendedPictureId

public static boolean setExtendedPictureId(byte[] buf,
                                           int off,
                                           int len,
                                           int val)

Sets the extended picture ID for the VP8 payload specified in the buffer that is passed as an argument.

Parameters:

buf - the byte buffer that contains the VP8 payload.

off - the offset in the byte buffer where the VP8 payload starts.

len - the length of the VP8 payload in the byte buffer.

Returns:

true if the operation succeeded, false otherwise.

setTL0PICIDX

public static boolean setTL0PICIDX(byte[] buf,
                                   int off,
                                   int len,
                                   int val)

Sets the TL0PICIDX field for the VP8 payload specified in the buffer that is passed as an argument.

Parameters:

buf - the byte buffer that contains the VP8 payload.

off - the offset in the byte buffer where the VP8 payload starts.

len - the length of the VP8 payload in the byte buffer.

Returns:

true if the operation succeeded, false otherwise.

isValid

public static boolean isValid(byte[] buf,
                              int off,
                              int len)

Checks whether the arguments specify a valid buffer.

Parameters:

buf -

off -

len -

Returns:

true if the arguments specify a valid buffer, false otherwise.

isStartOfPartition

public static boolean isStartOfPartition(byte[] input,
                                         int offset)

Checks whether the 'start of partition' bit is set in the VP8 Payload Descriptor at offset offset in input.

Parameters:

input - input

offset - offset

Returns:

true if the 'start of partition' bit is set, false otherwise.

isStartOfFrame

public static boolean isStartOfFrame(byte[] input,
                                     int offset)

Returns true if both the 'start of partition' bit is set and the PID fields has value 0 in the VP8 Payload Descriptor at offset offset in input.

Parameters:

input -

offset -

Returns:

true if both the 'start of partition' bit is set and the PID fields has value 0 in the VP8 Payload Descriptor at offset offset in input.

getPartitionId

public static int getPartitionId(byte[] input,
                                 int offset)

Returns the value of the PID (partition ID) field of the VP8 Payload Descriptor at offset offset in input.

Parameters:

input -

offset -

Returns:

the value of the PID (partition ID) field of the VP8 Payload Descriptor at offset offset in input.

isReference

public static boolean isReference(byte[] buf,
                                  int off,
                                  int len)

Gets a boolean that indicates whether or not the non-reference bit is set.

Parameters:

buf - the byte buffer that holds the VP8 payload descriptor.

off - the offset in the byte buffer where the payload descriptor starts.

len - the length of the payload descriptor in the byte buffer.

Returns:

true if the non-reference bit is NOT set, false otherwise.

getTL0PICIDX

public static int getTL0PICIDX(byte[] buf,
                               int off,
                               int len)

Gets the TL0PICIDX from the payload descriptor.

Parameters:

buf - the byte buffer that holds the VP8 payload descriptor.

off - the offset in the byte buffer where the payload descriptor starts.

len - the length of the payload descriptor in the byte buffer.

Returns:

the TL0PICIDX from the payload descriptor.

toString

public static String toString(byte[] buf,
                              int off,
                              int len)

Provides a string description of the VP8 descriptor that can be used for debugging purposes.

Parameters:

buf -

off -

len -

Returns: