Metadata

Episode-level session metadata is published on a single topic. The message carries rig and capture info, global time range, optional location, task/scene identifiers, operator and collection method, and the conversion batch version when available.

Topic & Message Type

• Topic: /session/metadata
• Message type: session.SessionMetadata
• Encoding: protobuf

Defined in session/metadata.proto; all messages include common.header.Header.

Message definition (metadata, one message per session):

syntax = "proto3";

package session;

import "common/header.proto";

message Resolution {
  uint32 height = 1;
  uint32 width = 2;
}

message CaptureDevice {
  string cam_model = 1;
  string device_type = 2;
  string firmware_version = 3;
  string fps = 4;
  string modality = 5;
  Resolution resolution = 6;
  int64 unix_start_time = 7;
  int64 unix_end_time = 8;
}

message GlobalTime {
  string start_time_iso = 1;
  string end_time_iso = 2;
  string timezone = 3;
}

message Location {
  string coordinate_system = 1;
  optional double latitude = 2;
  optional double longitude = 3;
}

message TaskInfo {
  string episode_uuid = 1;
  string task_name = 2;
  string task_description = 3;
  string environment_id = 4;
  string scene_id = 5;
}

message OperatorInfo {
  double arm_span = 1;
  double height = 2;
  double leg_length = 3;
  string unit = 4;
}

message CollectionMethod {
  string description = 1;
  string paradigm = 2;
}

message Operator {
  CollectionMethod collection_method = 1;
  string operator_id = 2;
  OperatorInfo operator_info = 3;
}

// Main message for topic /session/metadata
message SessionMetadata {
  common.header.Header header = 1;
  string batch_version = 2;
  repeated CaptureDevice devices = 3;
  GlobalTime global_time = 4;
  Location location = 5;
  TaskInfo task_info = 6;
  Operator operator = 7;
}