Publish with LSL

Together with the EEG data read from the hardware via the iobuffer interface, additional information can be published depending on the application use case.

Generally, the first channel is the sample index, followed by EEG data, followed by an appendix, e.g. phase, power, triggerstate etc.

On your local measurement PC, use on of the available LSL interfaces, e.g. pylsl, to connect with this data stream.

Defines

OUTLET_NAME

The name of the outlet. Defaults to LuckyLoop

OUTLET_CHANNEL_COUNT

The number of channels published with LSL

MAX_APPENDIX_COUNT

the maximal number of appendable items for publication with LSL, given the number of EEG channels defined by the connected iobuffered hardware.

Functions

void stack_outlet_sample(int32_t *outlet_sample, const int32_t sample_index, const int32_t *eegsample, const int32_t *appendix)

stack different items for publication with an LSL outlet order of array will be in order of the arguments, i.e. index, eeg, appendix.

Parameters

  • outlet_sample – array of data to be published with LSL, items will be stacked into this array

  • sample_index – monotonic count index of the current sample

  • eeg_sample – array with the current EEG samples

  • appendix – array with additional values to be appended after the EEG samples

void stack_variadic(int32_t *stacked, const int variadic_count, ...)

stack different items for publication with an LSL outlet

Parameters

  • stacked – array to be stacked into

  • variadic_count – how many single items will be appended after the appendix.

  • variadic – appendix of len variadic_count. each item must be of type int32_t

lsl_outlet init_lsl_outlet()

initialize the LSL outlet for publishing

unsigned int aton(char *ipaddress)

convert an IP-address string to unsigned interer

char *get_adapter_address(char *adaptername, size_t name_len)

get the IP address of an adapter specified by its name

Parameters

  • adaptername – the name of the adapter, e.h. eth0, eth1 or enp5s0

  • name_len – the length of the adaptername string

Returns

the ip address as a string. convert it to an integer with aton