Midi

Summary

Enumerations
Anonymous Enum 15{
AMIDI_OPCODE_DATA = 1,
AMIDI_OPCODE_FLUSH = 2
} 		enum
Anonymous Enum 16{
AMIDI_DEVICE_TYPE_USB = 1,
AMIDI_DEVICE_TYPE_VIRTUAL = 2,
AMIDI_DEVICE_TYPE_BLUETOOTH = 3
} 		enum
AMidiDevice_Protocol{
AMIDI_DEVICE_PROTOCOL_UMP_USE_MIDI_CI = 0,
AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS = 1,
AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS_AND_JRTS = 2,
AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_128_BITS = 3,
AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_128_BITS_AND_JRTS = 4,
AMIDI_DEVICE_PROTOCOL_UMP_MIDI_2_0 = 17,
AMIDI_DEVICE_PROTOCOL_UMP_MIDI_2_0_AND_JRTS = 18,
AMIDI_DEVICE_PROTOCOL_UNKNOWN = -1
} 		enum

Typedefs
AMidiDevice typedef
struct AMidiDevice
AMidiDevice_Protocol typedef
AMidiInputPort typedef
struct AMidiInputPort
AMidiOutputPort typedef
struct AMidiOutputPort

Functions
AMidiDevice_fromJava(JNIEnv *env, jobject midiDeviceObj, AMidiDevice **outDevicePtrPtr)
media_status_t AMIDI_API
Connects a native Midi Device object to the associated Java MidiDevice object.
AMidiDevice_getDefaultProtocol(const AMidiDevice *device)
Gets the MIDI device default protocol.
AMidiDevice_getNumInputPorts(const AMidiDevice *device)
ssize_t AMIDI_API
Gets the number of input (sending) ports available on the specified MIDI device.
AMidiDevice_getNumOutputPorts(const AMidiDevice *device)
ssize_t AMIDI_API
Gets the number of output (receiving) ports available on the specified MIDI device.
AMidiDevice_getType(const AMidiDevice *device)
int32_t AMIDI_API
Gets the MIDI device type.
AMidiDevice_release(const AMidiDevice *midiDevice)
media_status_t AMIDI_API
Disconnects the native Midi Device Object from the associated Java MidiDevice object.
AMidiInputPort_close(const AMidiInputPort *inputPort)
void AMIDI_API
Closes the input port.
AMidiInputPort_open(const AMidiDevice *device, int32_t portNumber, AMidiInputPort **outInputPortPtr)
media_status_t AMIDI_API
Opens the input port so that the client can send data to it.
AMidiInputPort_send(const AMidiInputPort *inputPort, const uint8_t *buffer, size_t numBytes)
ssize_t AMIDI_API
Sends data to the specified input port.
AMidiInputPort_sendFlush(const AMidiInputPort *inputPort)
media_status_t AMIDI_API
Sends a message with a 'MIDI flush command code' to the specified port.
AMidiInputPort_sendWithTimestamp(const AMidiInputPort *inputPort, const uint8_t *buffer, size_t numBytes, int64_t timestamp)
ssize_t AMIDI_API
Sends data to the specified input port with a timestamp.
AMidiOutputPort_close(const AMidiOutputPort *outputPort)
void AMIDI_API
Closes the output port.
AMidiOutputPort_open(const AMidiDevice *device, int32_t portNumber, AMidiOutputPort **outOutputPortPtr)
media_status_t AMIDI_API
Opens the output port so that the client can receive data from it.
AMidiOutputPort_receive(const AMidiOutputPort *outputPort, int32_t *opcodePtr, uint8_t *buffer, size_t maxBytes, size_t *numBytesReceivedPtr, int64_t *outTimestampPtr)
ssize_t AMIDI_API
Receives the next pending MIDI message.

Enumerations

Anonymous Enum 15

Declared in amidi/AMidi.h 
 Anonymous Enum 15

Anonymous Enum 16

Declared in amidi/AMidi.h 
 Anonymous Enum 16

AMidiDevice_Protocol

Declared in amidi/AMidi.h 
 AMidiDevice_Protocol
Properties
AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_128_BITS

Constant representing a default protocol with Universal MIDI Packets (UMP).

UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec. All UMP data should be a multiple of 4 bytes. Use MIDI 1.0 through UMP with packet sizes up to 128 bits.

AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_128_BITS_AND_JRTS

Constant representing a default protocol with Universal MIDI Packets (UMP).

UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec. All UMP data should be a multiple of 4 bytes. Use MIDI 1.0 through UMP with packet sizes up to 128 bits and jitter reduction timestamps.

AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS

Constant representing a default protocol with Universal MIDI Packets (UMP).

UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec. All UMP data should be a multiple of 4 bytes. Use MIDI 1.0 through UMP with packet sizes up to 64 bits.

AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS_AND_JRTS

Constant representing a default protocol with Universal MIDI Packets (UMP).

UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec. All UMP data should be a multiple of 4 bytes. Use MIDI 1.0 through UMP with packet sizes up to 64 bits and jitter reduction timestamps.

AMIDI_DEVICE_PROTOCOL_UMP_MIDI_2_0

Constant representing a default protocol with Universal MIDI Packets (UMP).

UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec. All UMP data should be a multiple of 4 bytes. Use MIDI 2.0 through UMP.

AMIDI_DEVICE_PROTOCOL_UMP_MIDI_2_0_AND_JRTS

Constant representing a default protocol with Universal MIDI Packets (UMP).

UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec. All UMP data should be a multiple of 4 bytes. Use MIDI 2.0 through UMP and jitter reduction timestamps.

AMIDI_DEVICE_PROTOCOL_UMP_USE_MIDI_CI

Constant representing a default protocol with Universal MIDI Packets (UMP).

UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec. All UMP data should be a multiple of 4 bytes. Use UMP to negotiate with the device with MIDI-CI. MIDI-CI is defined in "MIDI Capability Inquiry (MIDI-CI)" spec.

AMIDI_DEVICE_PROTOCOL_UNKNOWN

Constant representing a device with an unknown default protocol.

If Universal MIDI Packets (UMP) are needed, use MIDI-CI through MIDI 1.0. UMP is defined in "Universal MIDI Packet (UMP) Format and MIDI 2.0 Protocol" spec. MIDI-CI is defined in "MIDI Capability Inquiry (MIDI-CI)" spec.

Typedefs

AMidiDevice

Declared in amidi/AMidi.h 
struct AMidiDevice AMidiDevice

AMidiDevice_Protocol

Declared in amidi/AMidi.h 
enumAMidiDevice_Protocol AMidiDevice_Protocol

AMidiInputPort

Declared in amidi/AMidi.h 
struct AMidiInputPort AMidiInputPort

AMidiOutputPort

Declared in amidi/AMidi.h 
struct AMidiOutputPort AMidiOutputPort

Functions

AMidiDevice_fromJava

Declared in amidi/AMidi.h 
media_status_t AMIDI_API AMidiDevice_fromJava(
 JNIEnv *env,
 jobject midiDeviceObj,
 AMidiDevice **outDevicePtrPtr
)

Connects a native Midi Device object to the associated Java MidiDevice object.

Use this AMidiDevice to access the rest of the native MIDI API. Use AMidiDevice_release() to disconnect from the Java object when not being used any more.

See also:AMEDIA_ERROR_INVALID_OBJECT - the midiDeviceObj is null or already connected to a native AMidiDevice See also:AMEDIA_ERROR_UNKNOWN - an unknown error occurred.

Details
Parameters
env
Points to the Java Environment.
midiDeviceObj
The Java MidiDevice Object.
outDevicePtrPtr
Points to the pointer to receive the AMidiDevice
Returns
AMEDIA_OK on success, or a negative error value:

AMidiDevice_getDefaultProtocol

Declared in amidi/AMidi.h 
AMidiDevice_Protocol AMIDI_APIAMidiDevice_getDefaultProtocol(
constAMidiDevice*device
)

Gets the MIDI device default protocol.

Most devices should return PROTOCOL_UNKNOWN (-1). This is intentional as devices with default UMP support are not backwards compatible. When the device is null, return AMIDI_DEVICE_PROTOCOL_UNKNOWN.

Details
Parameters
device
Specifies the MIDI device.
Returns
The identifier of the MIDI device default protocol: AMIDI_DEVICE_PROTOCOL_UMP_USE_MIDI_CI AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_64_BITS_AND_JRTS AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_128_BITS AMIDI_DEVICE_PROTOCOL_UMP_MIDI_1_0_UP_TO_128_BITS_AND_JRTS AMIDI_DEVICE_PROTOCOL_UMP_MIDI_2_0 AMIDI_DEVICE_PROTOCOL_UMP_MIDI_2_0_AND_JRTS AMIDI_DEVICE_PROTOCOL_UNKNOWN

Available since API 33.

AMidiDevice_getNumInputPorts

Declared in amidi/AMidi.h 
ssize_tAMIDI_APIAMidiDevice_getNumInputPorts(
constAMidiDevice*device
)

Gets the number of input (sending) ports available on the specified MIDI device.

See also:AMEDIA_ERROR_INVALID_PARAMETER - the device parameter is NULL. See also:AMEDIA_ERROR_UNKNOWN - couldn't retrieve the device info.

Details
Parameters
device
Specifies the MIDI device.
Returns
If successful, returns the number of MIDI input (sending) ports available on the device. If an error occurs, returns a negative value indicating the error:

AMidiDevice_getNumOutputPorts

Declared in amidi/AMidi.h 
ssize_tAMIDI_APIAMidiDevice_getNumOutputPorts(
constAMidiDevice*device
)

Gets the number of output (receiving) ports available on the specified MIDI device.

See also:AMEDIA_ERROR_INVALID_PARAMETER - the device parameter is NULL. See also:AMEDIA_ERROR_UNKNOWN - couldn't retrieve the device info.

Details
Parameters
device
Specifies the MIDI device.
Returns
If successful, returns the number of MIDI output (receiving) ports available on the device. If an error occurs, returns a negative value indicating the error:

AMidiDevice_getType

Declared in amidi/AMidi.h 
int32_tAMIDI_APIAMidiDevice_getType(
constAMidiDevice*device
)

Gets the MIDI device type.

See also:AMEDIA_ERROR_INVALID_PARAMETER - the device parameter is NULL. See also:AMEDIA_ERROR_UNKNOWN - Unknown error.

Details
Parameters
device
Specifies the MIDI device.
Returns
The identifier of the MIDI device type: AMIDI_DEVICE_TYPE_USB AMIDI_DEVICE_TYPE_VIRTUAL AMIDI_DEVICE_TYPE_BLUETOOTH or a negative error value:

AMidiDevice_release

Declared in amidi/AMidi.h 
media_status_t AMIDI_APIAMidiDevice_release(
constAMidiDevice*midiDevice
)

Disconnects the native Midi Device Object from the associated Java MidiDevice object.

See also:AMEDIA_ERROR_INVALID_PARAMETER - the device parameter is NULL. See also:AMEDIA_ERROR_INVALID_OBJECT - the device is not consistent with the associated Java MidiDevice. See also:AMEDIA_ERROR_INVALID_OBJECT - the JNI interface initialization to the associated java MidiDevice failed. See also:AMEDIA_ERROR_UNKNOWN - couldn't retrieve the device info.

Details
Parameters
midiDevice
Points to the native AMIDI_MidiDevice.
Returns
AMEDIA_OK on success, or a negative error value:

AMidiInputPort_close

Declared in amidi/AMidi.h 
voidAMIDI_APIAMidiInputPort_close(
constAMidiInputPort*inputPort
)

Closes the input port.

Details
Parameters
inputPort
Identifies the input (sending) port to close.

AMidiInputPort_open

Declared in amidi/AMidi.h 
media_status_t AMIDI_APIAMidiInputPort_open(
constAMidiDevice*device,
int32_tportNumber,
AMidiInputPort**outInputPortPtr
)

Opens the input port so that the client can send data to it.

The port remains open and valid until AMidiInputPort_close() is called for the returned AMidiInputPort.

See also:AMEDIA_ERROR_UNKNOWN - Unknown Error.

Details
Parameters
device
Specifies the MIDI device.
portNumber
Specifies the zero-based port index on the device to open. This value ranges between 0 and one less than the number of input ports reported by the AMidiDevice_getNumInputPorts() function..
outInputPortPtr
Receives the native API port identifier of the opened port.
Returns
AMEDIA_OK, or a negative error code:

AMidiInputPort_send

Declared in amidi/AMidi.h 
ssize_tAMIDI_APIAMidiInputPort_send(
constAMidiInputPort*inputPort,
constuint8_t*buffer,
size_tnumBytes
)

Sends data to the specified input port.

See also:AMEDIA_ERROR_INVALID_PARAMETER - The specified port was NULL, the specified buffer was NULL.

Details
Parameters
inputPort
The identifier of the port to send data to.
buffer
Points to the array of bytes containing the data to send.
numBytes
Specifies the number of bytes to write.
Returns
The number of bytes sent, which could be less than specified or a negative error code:

AMidiInputPort_sendFlush

Declared in amidi/AMidi.h 
media_status_t AMIDI_APIAMidiInputPort_sendFlush(
constAMidiInputPort*inputPort
)

Sends a message with a 'MIDI flush command code' to the specified port.

This should cause a receiver to discard any pending MIDI data it may have accumulated and not processed.

See also:AMEDIA_OK if successful, otherwise a negative error code: See also:AMEDIA_ERROR_INVALID_PARAMETER - The specified port was NULL See also:AMEDIA_ERROR_UNSUPPORTED - The FLUSH command couldn't be sent.

Details
Parameters
inputPort
The identifier of the port to send the flush command to.
Returns

AMidiInputPort_sendWithTimestamp

Declared in amidi/AMidi.h 
ssize_tAMIDI_APIAMidiInputPort_sendWithTimestamp(
constAMidiInputPort*inputPort,
constuint8_t*buffer,
size_tnumBytes,
int64_ttimestamp
)

Sends data to the specified input port with a timestamp.

See also:AMEDIA_ERROR_INVALID_PARAMETER - The specified port was NULL, the specified buffer was NULL.

Details
Parameters
inputPort
The identifier of the port to send data to.
buffer
Points to the array of bytes containing the data to send.
numBytes
Specifies the number of bytes to write.
timestamp
The CLOCK_MONOTONIC time in nanoseconds to associate with the sent data.
Returns
The number of bytes sent, which could be less than specified or a negative error code:

AMidiOutputPort_close

Declared in amidi/AMidi.h 
voidAMIDI_APIAMidiOutputPort_close(
constAMidiOutputPort*outputPort
)

Closes the output port.

Details
Parameters
outputPort
The native API port identifier of the port.

AMidiOutputPort_open

Declared in amidi/AMidi.h 
media_status_t AMIDI_APIAMidiOutputPort_open(
constAMidiDevice*device,
int32_tportNumber,
AMidiOutputPort**outOutputPortPtr
)

Opens the output port so that the client can receive data from it.

The port remains open and valid until AMidiOutputPort_close() is called for the returned AMidiOutputPort.

See also:AMEDIA_ERROR_UNKNOWN - Unknown Error.

Details
Parameters
device
Specifies the MIDI device.
portNumber
Specifies the zero-based port index on the device to open. This value ranges between 0 and one less than the number of output ports reported by the AMidiDevice_getNumOutputPorts function.
outOutputPortPtr
Receives the native API port identifier of the opened port.
Returns
AMEDIA_OK, or a negative error code:

AMidiOutputPort_receive

Declared in amidi/AMidi.h 
ssize_tAMIDI_APIAMidiOutputPort_receive(
constAMidiOutputPort*outputPort,
int32_t*opcodePtr,
uint8_t*buffer,
size_tmaxBytes,
size_t*numBytesReceivedPtr,
int64_t*outTimestampPtr
)

Receives the next pending MIDI message.

To retrieve all pending messages, the client should repeatedly call this method until it returns 0.

Note that this is a non-blocking call. If there are no Midi messages are available, the function returns 0 immediately (for 0 messages received).

See also:AMEDIA_ERROR_UNKNOWN - Unknown Error.

Details
Parameters
outputPort
Identifies the port to receive messages from.
opcodePtr
Receives the message Op Code.
buffer
Points to the buffer to receive the message data bytes.
maxBytes
Specifies the size of the buffer pointed to by the buffer parameter.
numBytesReceivedPtr
On exit, receives the actual number of bytes stored in buffer.
outTimestampPtr
If non-NULL, receives the timestamp associated with the message. (the current value of the running Java Virtual Machine's high-resolution time source, in nanoseconds)
Returns
the number of messages received (either 0 or 1), or a negative error code:

Content and code samples on this page are subject to the licenses described in the Content License. Java and OpenJDK are trademarks or registered trademarks of Oracle and/or its affiliates.

Last updated 2025年11月03日 UTC.