BASS_MIDI_StreamCreate

Creates a sample stream to render real-time MIDI events.

HSTREAM BASS_MIDI_StreamCreate(
    DWORD channels,
    DWORD flags,
    DWORD freq
);

Parameters

channels

The number of MIDI channels... 1 (min) - 128 (max). The number of channels can subsequently be changed via the BASS_ATTRIB_MIDI_CHANS attribute.

flags

A combination of these flags.

BASS_SAMPLE_8BITS	Use 8-bit resolution. If neither this or the BASS_SAMPLE_FLOAT flags are specified, then the sample data will be 16-bit.
BASS_SAMPLE_FLOAT	Use 32-bit floating-point sample data. See Floating-point channels for more info.
BASS_SAMPLE_MONO	Decode/play the MIDI in mono (uses less CPU than stereo). This flag is automatically applied if BASS_DEVICE_MONO was specified when calling BASS_Init.
BASS_SAMPLE_SOFTWARE	Force the stream to not use hardware mixing.
BASS_SAMPLE_3D	Enable 3D functionality. This requires that the BASS_DEVICE_3D flag was specified when calling BASS_Init. 3D channels must also be mono, so BASS_SAMPLE_MONO is automatically applied. The SPEAKER flags cannot be used together with this flag.
BASS_SAMPLE_FX	Enable the old implementation of DirectX 8 effects. See the DX8 effect implementations section for details. Use BASS_ChannelSetFX to add effects to the stream.
BASS_STREAM_AUTOFREE	Automatically free the stream when playback ends.
BASS_STREAM_DECODE	Decode/render the sample data, without playing it. Use BASS_ChannelGetData to retrieve decoded sample data. The BASS_SAMPLE_3D, BASS_STREAM_AUTOFREE and SPEAKER flags cannot be used together with this flag. The BASS_SAMPLE_SOFTWARE and BASS_SAMPLE_FX flags are also ignored.
BASS_SPEAKER_xxx	Speaker assignment flags. The BASS_SAMPLE_MONO flag is automatically applied when using a mono speaker assignment flag.
BASS_MIDI_NOFX	Disable reverb and chorus processing, saving some CPU time. This flag can be toggled at any time using BASS_ChannelFlags.
BASS_MIDI_NOSYSRESET	Ignore system reset events (MIDI_EVENT_SYSTEM) when the system mode is unchanged. This flag can be toggled at any time using BASS_ChannelFlags.
BASS_MIDI_NOTEOFF1	Only release the oldest instance upon a note off event (MIDI_EVENT_NOTE with velocity=0) when there are overlapping instances of the note. Otherwise all instances are released. This flag can be toggled at any time using BASS_ChannelFlags.
BASS_MIDI_SINCINTER	Use sinc interpolated sample mixing. This increases the sound quality, but also requires more CPU. Otherwise linear interpolation is used. The sinc interpolation uses 8 points by default, but 16 point sinc interpolation is also available via the BASS_ATTRIB_MIDI_SRC attribute.

freq

Sample rate to render/play the MIDI stream at... 0 = the rate specified in the BASS_Init call, 1 = the device's current output rate (or the BASS_Init rate if that is not available).

Return value

If successful, the new stream's handle is returned, else 0 is returned. Use BASS_ErrorGetCode to get the error code.

Error codes

BASS_ERROR_INIT	BASS_Init has not been successfully called.
BASS_ERROR_NOTAVAIL	Only decoding channels (BASS_STREAM_DECODE) are allowed when using the "no sound" device. The BASS_STREAM_AUTOFREE flag is also unavailable to decoding channels.
BASS_ERROR_ILLPARAM	channels is not valid.
BASS_ERROR_FORMAT	The sample format is not supported by the device/drivers. If the stream is more than stereo or the BASS_SAMPLE_FLOAT flag is used, it could be that they are not supported.
BASS_ERROR_SPEAKER	The specified SPEAKER flags are invalid. The device/drivers do not support them or 3D functionality is enabled.
BASS_ERROR_MEM	There is insufficient memory.
BASS_ERROR_NO3D	Could not initialize 3D support.
BASS_ERROR_UNKNOWN	Some other mystery problem!

Remarks

This function creates a stream solely for real-time MIDI events. As it is not based on any file, the stream has no predetermined length and is never-ending. Seeking is not possible, but it is possible to reset everything, including playback buffer, by calling BASS_ChannelPlay (restart = TRUE) or BASS_ChannelSetPosition (pos = 0).

MIDI events are applied using the BASS_MIDI_StreamEvent and BASS_MIDI_StreamEvents functions. If the stream is being played (it is not a decoding channel), then there will be some delay in the effect of the events being heard. This latency can be reduced by making use of the BASS_CONFIG_BUFFER and BASS_CONFIG_UPDATEPERIOD config options.

If a stream has 16 MIDI channels, then channel 10 defaults to percussion/drums and the rest melodic, otherwise they are all melodic. That can be changed using BASS_MIDI_StreamEvent and the MIDI_EVENT_DRUMS event.

Soundfonts provide the sounds that are used to render a MIDI stream. A default soundfont configuration is applied initially to the new MIDI stream, which can subsequently be overridden using BASS_MIDI_StreamSetFonts.

To play a MIDI file, use BASS_MIDI_StreamCreateFile.

Platform-specific

Away from Windows, all mixing is done in software (by BASS), so the BASS_SAMPLE_SOFTWARE flag is unnecessary. The BASS_SAMPLE_FX flag is also ignored. On Android and iOS, sinc interpolation requires a NEON-supporting CPU; the BASS_MIDI_SINCINTER flag will otherwise be ignored. Sinc interpolation is not available on Windows CE.

BASS MIDI