MessageGroup¶

The MessageGroup message type is a versatile container used in DepthAI pipelines to group together a map of arbitrary DepthAI messages. It serves as the primary output of the Sync node, effectively synchronizing various input streams, and acts as the input to the MessageDemux node for subsequent disaggregation and processing.

Creating MessageGroup¶

MessageGroup can be created automatically by the Sync node as it aligns and groups messages from different sources based on their timestamps. Alternatively, it can be manually constructed in a host application or within a Script node to create custom groupings of DepthAI messages.

Reference¶

class depthai.MessageGroup

getData(self: object) → numpy.ndarray[numpy.uint8]

getIntervalNs(self: depthai.MessageGroup) → int

getMessageNames(self: depthai.MessageGroup) → list[str]

getNumMessages(self: depthai.MessageGroup) → int

getRaw(self: depthai.ADatatype) → depthai.RawBuffer

getSequenceNum(self: depthai.MessageGroup) → int

getTimestamp(self: depthai.MessageGroup) → datetime.timedelta

getTimestampDevice(self: depthai.MessageGroup) → datetime.timedelta

isSynced(self: depthai.MessageGroup, arg0: int) → bool

setData(*args, **kwargs)

Overloaded function.

setData(self: depthai.Buffer, arg0: list[int]) -> None
setData(self: depthai.Buffer, arg0: numpy.ndarray[numpy.uint8]) -> None

setSequenceNum(self: depthai.MessageGroup, arg0: int) → depthai.MessageGroup

setTimestamp(self: depthai.MessageGroup, arg0: datetime.timedelta) → depthai.MessageGroup

setTimestampDevice(self: depthai.MessageGroup, arg0: datetime.timedelta) → depthai.MessageGroup

class dai::MessageGroup : public dai::Buffer ¶

MessageGroup message. Carries multiple messages in one.

Public Functions

MessageGroup()¶: Construct MessageGroup message.

MessageGroup(std::shared_ptr<RawMessageGroup> ptr)¶

~MessageGroup() = default¶

std::shared_ptr<ADatatype> operator[](const std::string &name)¶: Group.

template<typename T> std::shared_ptr<T> get(const std::string &name)¶

void add(const std::string &name, const std::shared_ptr<ADatatype> &value)¶

template<typename T> void add(const std::string &name, const T &value)¶

std::unordered_map<std::string, std::shared_ptr<ADatatype>>::iterator begin()¶

std::unordered_map<std::string, std::shared_ptr<ADatatype>>::iterator end()¶

bool isSynced(int64_t thresholdNs) const¶

True if all messages in the group are in the interval

Parameters

thresholdNs: Maximal interval between messages

int64_t getIntervalNs() const¶: Retrieves interval between the first and the last message in the group.

int64_t getNumMessages() const¶

std::vector<std::string> getMessageNames() const¶: Gets the names of messages in the group

MessageGroup &setTimestamp(std::chrono::time_point<std::chrono::steady_clock, std::chrono::steady_clock::duration> timestamp)¶: Sets image timestamp related to dai::Clock::now()

MessageGroup &setTimestampDevice(std::chrono::time_point<std::chrono::steady_clock, std::chrono::steady_clock::duration> timestamp)¶: Sets image timestamp related to dai::Clock::now()

MessageGroup &setSequenceNum(int64_t sequenceNum)¶: Retrieves image sequence number

Private Functions

std::shared_ptr<RawBuffer> serialize() const override¶

Private Members

RawMessageGroup &rawGrp¶

std::unordered_map<std::string, std::shared_ptr<ADatatype>> group¶

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