{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "urn:animsmith:schema:measurements:16",
  "title": "animsmith measurements v16",
  "description": "Animation measurements including artifact-derived per-bone TRS channel coverage, sampled normalized-model-space Root/Hips trajectory evidence, loop endpoint and declared frame-grid evidence, per-primitive finite geometry summaries, bounded unsupported-image magic evidence, plus static scene-bound, source material-resource, and source skeleton/rest-pose transform-domain measurements shared by measure and lint output. Every clip fact that is not applicable to every clip carries a sibling `_availability` status distinguishing `not_applicable` (this clip has no subject for the fact) from `unavailable` (the subject applies, but derivation failed); the value field is present exactly when that status is `measured`.",
  "type": "object",
  "required": ["schema_version", "schema", "clips", "material_resource_coverage", "material_definitions", "textures", "images", "mesh_definitions", "node_instances", "scenes", "skeleton_source_coverage", "skeleton_nodes", "skins"],
  "properties": {
    "schema_version": { "const": 16 },
    "schema": { "const": "urn:animsmith:schema:measurements:16" },
    "clips": { "type": "object", "additionalProperties": { "$ref": "#/$defs/clip_measurements" } },
    "material_resource_coverage": { "enum": ["complete", "unavailable"] },
    "material_definitions": { "type": "array", "items": { "$ref": "#/$defs/material_definition" } },
    "textures": { "type": "array", "items": { "$ref": "#/$defs/texture" } },
    "images": { "type": "array", "items": { "$ref": "#/$defs/image" } },
    "mesh_definitions": { "type": "array", "items": { "$ref": "#/$defs/mesh_definition" } },
    "node_instances": { "type": "array", "items": { "$ref": "#/$defs/node_instance" } },
    "scenes": { "type": "array", "items": { "$ref": "#/$defs/scene" } },
    "default_scene_index": { "type": "integer", "minimum": 0 },
    "skeleton_source_coverage": { "enum": ["complete", "unavailable"] },
    "skeleton_nodes": { "type": "array", "items": { "$ref": "#/$defs/skeleton_node" } },
    "skins": { "type": "array", "items": { "$ref": "#/$defs/skin" } }
  },
  "allOf": [
    {
      "if": { "properties": { "material_resource_coverage": { "const": "unavailable" } }, "required": ["material_resource_coverage"] },
      "then": {
        "properties": {
          "material_definitions": { "maxItems": 0 },
          "textures": { "maxItems": 0 },
          "images": { "maxItems": 0 }
        }
      }
    },
    {
      "if": { "properties": { "skeleton_source_coverage": { "const": "unavailable" } }, "required": ["skeleton_source_coverage"] },
      "then": {
        "properties": {
          "skeleton_nodes": { "maxItems": 0 },
          "skins": { "maxItems": 0 }
        }
      }
    }
  ],
  "$defs": {
    "measurement_availability": { "enum": ["measured", "not_applicable", "unavailable"] },
    "clip_measurements": {
      "type": "object",
      "required": [
        "duration_s", "frame_count", "animated_bones", "bone_channels", "bone_rotation_range_deg",
        "loop_continuity_availability", "loop_endpoint_mode_availability",
        "frame_grid_availability", "loop_seam_ratio_availability", "gait_availability",
        "root_trajectory_availability", "speed_mps_availability"
      ],
      "properties": {
        "duration_s": { "type": "number" }, "frame_count": { "type": "integer", "minimum": 0 },
        "animated_bones": { "type": "array", "uniqueItems": true, "items": { "type": "string" } },
        "bone_channels": {
          "type": "array",
          "uniqueItems": true,
          "description": "Canonical set of non-empty local TRS channels present in the measured document, grouped by skeleton bone index. This describes artifact coverage, not requested transforms, removed-track evidence, or track multiplicity.",
          "items": { "$ref": "#/$defs/bone_channels" }
        },
        "bone_rotation_range_deg": {
          "type": "object",
          "description": "Maximum rotation deviation for structurally valid keyed rotation channels above the recording floor. Every key is also present in animated_bones; that cross-field invariant is enforced by the core contract validator.",
          "additionalProperties": { "type": "number" }
        },
        "loop_continuity": { "$ref": "#/$defs/loop_continuity" },
        "loop_continuity_availability": { "$ref": "#/$defs/measurement_availability" },
        "loop_endpoint_mode": { "enum": ["unique_cycle", "duplicate_endpoint", "non_closing"] },
        "loop_endpoint_mode_availability": { "$ref": "#/$defs/measurement_availability" },
        "frame_grid": { "$ref": "#/$defs/frame_grid" },
        "frame_grid_availability": { "$ref": "#/$defs/measurement_availability" },
        "loop_seam_ratio": { "type": "number" },
        "loop_seam_ratio_availability": { "$ref": "#/$defs/measurement_availability" },
        "gait": { "$ref": "#/$defs/gait" },
        "gait_availability": { "$ref": "#/$defs/measurement_availability" },
        "root_trajectory": { "$ref": "#/$defs/root_trajectory" },
        "root_trajectory_availability": { "$ref": "#/$defs/measurement_availability" },
        "speed_mps": { "type": "number" },
        "speed_mps_availability": { "$ref": "#/$defs/measurement_availability" }
      },
      "allOf": [
        {
          "if": { "properties": { "loop_continuity_availability": { "const": "measured" } }, "required": ["loop_continuity_availability"] },
          "then": { "required": ["loop_continuity"] },
          "else": { "not": { "required": ["loop_continuity"] } }
        },
        {
          "if": { "properties": { "loop_endpoint_mode_availability": { "const": "measured" } }, "required": ["loop_endpoint_mode_availability"] },
          "then": { "required": ["loop_endpoint_mode"] },
          "else": { "not": { "required": ["loop_endpoint_mode"] } }
        },
        {
          "if": { "properties": { "frame_grid_availability": { "const": "measured" } }, "required": ["frame_grid_availability"] },
          "then": { "required": ["frame_grid"] },
          "else": { "not": { "required": ["frame_grid"] } }
        },
        {
          "if": { "properties": { "loop_seam_ratio_availability": { "const": "measured" } }, "required": ["loop_seam_ratio_availability"] },
          "then": { "required": ["loop_seam_ratio"] },
          "else": { "not": { "required": ["loop_seam_ratio"] } }
        },
        {
          "if": { "properties": { "gait_availability": { "const": "measured" } }, "required": ["gait_availability"] },
          "then": { "required": ["gait"] },
          "else": { "not": { "required": ["gait"] } }
        },
        {
          "if": { "properties": { "root_trajectory_availability": { "const": "measured" } }, "required": ["root_trajectory_availability"] },
          "then": { "required": ["root_trajectory"] },
          "else": { "not": { "required": ["root_trajectory"] } }
        },
        {
          "if": { "properties": { "speed_mps_availability": { "const": "measured" } }, "required": ["speed_mps_availability"] },
          "then": { "required": ["speed_mps"] },
          "else": { "not": { "required": ["speed_mps"] } }
        }
      ],
      "additionalProperties": false
    },
    "bone_channels": {
      "type": "object",
      "required": ["bone_index", "bone_name", "properties"],
      "properties": {
        "bone_index": { "type": "integer", "minimum": 0 },
        "bone_name": { "type": "string" },
        "properties": {
          "description": "Non-empty canonical subset in translation, rotation, scale order.",
          "enum": [
            ["translation"],
            ["rotation"],
            ["scale"],
            ["translation", "rotation"],
            ["translation", "scale"],
            ["rotation", "scale"],
            ["translation", "rotation", "scale"]
          ]
        }
      },
      "additionalProperties": false
    },
    "gait": {
      "type": "object",
      "required": ["lr_amplitude_m", "phase_availability"],
      "properties": {
        "phase": { "type": "number" },
        "phase_availability": { "$ref": "#/$defs/measurement_availability" },
        "lr_amplitude_m": { "type": "number" }
      },
      "allOf": [
        {
          "if": { "properties": { "phase_availability": { "const": "measured" } }, "required": ["phase_availability"] },
          "then": { "required": ["phase"] },
          "else": { "not": { "required": ["phase"] } }
        }
      ],
      "additionalProperties": false
    },
    "root_trajectory": {
      "type": "object",
      "required": ["bone_index", "bone_name", "source_role", "translation_availability", "yaw_availability"],
      "properties": {
        "bone_index": { "type": "integer", "minimum": 0 },
        "bone_name": { "type": "string" },
        "source_role": { "enum": ["root", "hips_fallback"] },
        "translation": { "$ref": "#/$defs/root_translation" },
        "translation_availability": { "enum": ["measured", "unavailable"] },
        "yaw": { "$ref": "#/$defs/root_yaw" },
        "yaw_availability": { "enum": ["measured", "unavailable"] }
      },
      "allOf": [
        {
          "if": { "properties": { "translation_availability": { "const": "measured" } }, "required": ["translation_availability"] },
          "then": { "required": ["translation"] },
          "else": { "not": { "required": ["translation"] } }
        },
        {
          "if": { "properties": { "yaw_availability": { "const": "measured" } }, "required": ["yaw_availability"] },
          "then": { "required": ["yaw"] },
          "else": { "not": { "required": ["yaw"] } }
        }
      ],
      "additionalProperties": false
    },
    "root_translation": {
      "type": "object",
      "required": ["horizontal_displacement_x_m", "horizontal_displacement_z_m", "horizontal_travel_m", "vertical_displacement_m", "vertical_min_displacement_m", "vertical_max_displacement_m"],
      "properties": {
        "horizontal_displacement_x_m": { "type": "number" },
        "horizontal_displacement_z_m": { "type": "number" },
        "horizontal_travel_m": { "type": "number", "minimum": 0 },
        "vertical_displacement_m": { "type": "number" },
        "vertical_min_displacement_m": { "type": "number", "maximum": 0 },
        "vertical_max_displacement_m": { "type": "number", "minimum": 0 }
      },
      "additionalProperties": false
    },
    "root_yaw": {
      "type": "object",
      "required": ["heading_axis", "net_yaw_deg", "unwrapped_yaw_deg", "yaw_travel_deg"],
      "properties": {
        "heading_axis": { "enum": ["positive_z", "positive_y", "positive_x"] },
        "net_yaw_deg": { "type": "number", "minimum": -180, "maximum": 180 },
        "unwrapped_yaw_deg": { "type": "number" },
        "yaw_travel_deg": { "type": "number", "minimum": 0 }
      },
      "additionalProperties": false
    },
    "frame_grid": { "type": "object", "required": ["fps", "frame_intervals"], "properties": { "fps": { "type": "number", "exclusiveMinimum": 0 }, "frame_intervals": { "type": "integer", "minimum": 1 } }, "additionalProperties": false },
    "loop_continuity": {
      "type": "object",
      "required": ["bones"],
      "properties": {
        "bones": {
          "type": "array",
          "minItems": 1,
          "items": { "$ref": "#/$defs/bone_loop_continuity" }
        }
      },
      "additionalProperties": false
    },
    "bone_loop_continuity": {
      "type": "object",
      "required": ["bone_index", "bone_name", "position_delta_m", "rotation_delta_deg", "seam_velocity_delta_mps", "seam_angular_velocity_delta_degps"],
      "properties": {
        "bone_index": { "type": "integer", "minimum": 0 },
        "bone_name": { "type": "string" },
        "position_delta_m": { "type": "number", "minimum": 0 },
        "rotation_delta_deg": { "type": "number", "minimum": 0 },
        "seam_velocity_delta_mps": { "type": "number", "minimum": 0 },
        "seam_angular_velocity_delta_degps": { "type": "number", "minimum": 0 }
      },
      "additionalProperties": false
    },
    "mesh_definition": {
      "type": "object",
      "required": ["mesh_index", "name", "primitives", "vertex_count", "max_joints_per_vertex", "additional_influence_sets"],
      "properties": {
        "mesh_index": { "type": "integer", "minimum": 0 }, "name": { "type": "string" },
        "primitives": { "type": "array", "items": { "$ref": "#/$defs/primitive_measurements" } },
        "vertex_count": { "type": "integer", "minimum": 0 }, "geometry_aabb": { "$ref": "#/$defs/aabb" }, "geometry_centroid": { "$ref": "#/$defs/vec3" },
        "max_joints_per_vertex": { "type": "integer", "minimum": 0 }, "weight_sum_min": { "type": "number" }, "weight_sum_max": { "type": "number" },
        "additional_influence_sets": { "type": "array", "items": { "$ref": "#/$defs/additional_influence_set" } }
      },
      "additionalProperties": false
    },
    "primitive_measurements": {
      "type": "object",
      "required": ["primitive_index", "material_index", "vertex_count", "finite_vertex_count"],
      "properties": {
        "primitive_index": { "type": "integer", "minimum": 0 },
        "material_index": { "type": ["integer", "null"], "minimum": 0 },
        "vertex_count": { "type": "integer", "minimum": 0 },
        "finite_vertex_count": { "type": "integer", "minimum": 0 },
        "geometry_aabb": { "$ref": "#/$defs/aabb" },
        "geometry_centroid": { "$ref": "#/$defs/vec3" }
      },
      "oneOf": [
        {
          "properties": { "finite_vertex_count": { "const": 0 } },
          "not": { "anyOf": [{ "required": ["geometry_aabb"] }, { "required": ["geometry_centroid"] }] }
        },
        {
          "properties": { "finite_vertex_count": { "minimum": 1 } },
          "required": ["geometry_aabb", "geometry_centroid"]
        }
      ],
      "additionalProperties": false
    },
    "additional_influence_set": {
      "type": "object",
      "required": ["set_index", "joints_present", "weights_present", "joints_without_weights_present", "weights_without_joints_present"],
      "properties": {
        "set_index": { "type": "integer", "minimum": 1 },
        "joints_present": { "type": "boolean" },
        "weights_present": { "type": "boolean" },
        "joints_without_weights_present": { "type": "boolean" },
        "weights_without_joints_present": { "type": "boolean" }
      },
      "anyOf": [
        { "properties": { "joints_present": { "const": true } } },
        { "properties": { "weights_present": { "const": true } } }
      ],
      "allOf": [
        {
          "if": { "properties": { "joints_without_weights_present": { "const": true } } },
          "then": { "properties": { "joints_present": { "const": true } } }
        },
        {
          "if": { "properties": { "weights_without_joints_present": { "const": true } } },
          "then": { "properties": { "weights_present": { "const": true } } }
        },
        {
          "if": { "properties": { "joints_present": { "const": true }, "weights_present": { "const": false } } },
          "then": { "properties": { "joints_without_weights_present": { "const": true } } }
        },
        {
          "if": { "properties": { "weights_present": { "const": true }, "joints_present": { "const": false } } },
          "then": { "properties": { "weights_without_joints_present": { "const": true } } }
        }
      ],
      "additionalProperties": false
    },
    "node_instance": {
      "type": "object",
      "required": ["node_index", "node_name", "mesh_index"],
      "properties": {
        "node_index": { "type": "integer", "minimum": 0 }, "node_name": { "type": "string" }, "mesh_index": { "type": "integer", "minimum": 0 },
        "static_node_world_aabb": { "$ref": "#/$defs/aabb" },
        "static_node_world_aabb_unavailable_reason": { "enum": ["no_finite_positions", "skinned_deformation_excluded", "non_finite_transform"] }
      },
      "oneOf": [
        { "required": ["static_node_world_aabb"], "not": { "required": ["static_node_world_aabb_unavailable_reason"] } },
        { "required": ["static_node_world_aabb_unavailable_reason"], "not": { "required": ["static_node_world_aabb"] } }
      ],
      "additionalProperties": false
    },
    "scene": {
      "type": "object",
      "required": ["scene_index", "instance_count", "excluded_instance_count"],
      "properties": {
        "scene_index": { "type": "integer", "minimum": 0 }, "name": { "type": "string" },
        "instance_count": { "type": "integer", "minimum": 0 },
        "static_scene_world_aabb": { "$ref": "#/$defs/aabb" }, "excluded_instance_count": { "type": "integer", "minimum": 0 }
      },
      "additionalProperties": false
    },
    "material_definition": {
      "type": "object",
      "required": ["material_index", "texture_bindings"],
      "properties": {
        "material_index": { "type": "integer", "minimum": 0 },
        "name": { "type": "string" },
        "texture_bindings": { "type": "array", "items": { "$ref": "#/$defs/material_texture_binding" } }
      },
      "additionalProperties": false
    },
    "material_texture_binding": {
      "type": "object",
      "required": ["slot", "texture_index"],
      "properties": {
        "slot": { "enum": ["base_color", "normal", "metallic_roughness", "occlusion", "emissive"] },
        "texture_index": { "type": "integer", "minimum": 0 }
      },
      "additionalProperties": false
    },
    "texture": {
      "type": "object",
      "required": ["texture_index", "image_index"],
      "properties": {
        "texture_index": { "type": "integer", "minimum": 0 },
        "name": { "type": "string" },
        "image_index": { "type": "integer", "minimum": 0 }
      },
      "additionalProperties": false
    },
    "image": {
      "type": "object",
      "required": ["image_index", "source_kind"],
      "properties": {
        "image_index": { "type": "integer", "minimum": 0 },
        "name": { "type": "string" },
        "source_kind": { "enum": ["embedded", "data_uri", "external"] },
        "declared_mime_type": { "type": "string" },
        "detected_container": { "enum": ["png", "jpeg"] },
        "width": { "type": "integer", "minimum": 1 },
        "height": { "type": "integer", "minimum": 1 },
        "channel_count": { "type": "integer", "minimum": 1, "maximum": 4 },
        "decoded_color_type": { "enum": ["l8", "la8", "rgb8", "rgba8", "l16", "la16", "rgb16", "rgba16"] },
        "leading_magic_hex": { "type": "string", "pattern": "^(?:[0-9a-f]{2}){1,16}$" },
        "unavailable_reason": { "enum": ["source_unavailable", "invalid_data_uri", "unsupported_container", "decode_failed", "resource_limit"] }
      },
      "oneOf": [
        {
          "required": ["detected_container", "width", "height", "channel_count", "decoded_color_type"],
          "not": { "required": ["unavailable_reason"] }
        },
        {
          "required": ["unavailable_reason"],
          "not": { "anyOf": [
            { "required": ["width"] }, { "required": ["height"] },
            { "required": ["channel_count"] }, { "required": ["decoded_color_type"] }
          ] }
        }
      ],
      "allOf": [
        {
          "if": { "required": ["leading_magic_hex"] },
          "then": {
            "properties": { "unavailable_reason": { "const": "unsupported_container" } },
            "required": ["unavailable_reason"],
            "not": { "required": ["detected_container"] }
          }
        },
        {
          "if": { "properties": { "unavailable_reason": { "enum": ["source_unavailable", "invalid_data_uri", "decode_failed", "resource_limit"] } }, "required": ["unavailable_reason"] },
          "then": { "not": { "required": ["leading_magic_hex"] } }
        },
        {
          "if": { "properties": { "unavailable_reason": { "const": "decode_failed" } }, "required": ["unavailable_reason"] },
          "then": { "required": ["detected_container"] }
        },
        {
          "if": { "properties": { "unavailable_reason": { "enum": ["source_unavailable", "invalid_data_uri", "unsupported_container"] } }, "required": ["unavailable_reason"] },
          "then": { "not": { "required": ["detected_container"] } }
        },
        {
          "if": { "properties": { "decoded_color_type": { "enum": ["l8", "l16"] } }, "required": ["decoded_color_type"] },
          "then": { "properties": { "channel_count": { "const": 1 } } }
        },
        {
          "if": { "properties": { "decoded_color_type": { "enum": ["la8", "la16"] } }, "required": ["decoded_color_type"] },
          "then": { "properties": { "channel_count": { "const": 2 } } }
        },
        {
          "if": { "properties": { "decoded_color_type": { "enum": ["rgb8", "rgb16"] } }, "required": ["decoded_color_type"] },
          "then": { "properties": { "channel_count": { "const": 3 } } }
        },
        {
          "if": { "properties": { "decoded_color_type": { "enum": ["rgba8", "rgba16"] } }, "required": ["decoded_color_type"] },
          "then": { "properties": { "channel_count": { "const": 4 } } }
        }
      ],
      "additionalProperties": false
    },
    "skeleton_node": {
      "type": "object",
      "required": ["node_index", "local_rest", "scene_root_indices", "rest_world_linear"],
      "properties": {
        "node_index": { "type": "integer", "minimum": 0 },
        "name": { "type": "string" },
        "parent_node_index": { "type": ["integer", "null"], "minimum": 0 },
        "scene_root_indices": { "type": "array", "items": { "type": "integer", "minimum": 0 } },
        "local_rest": { "$ref": "#/$defs/local_rest" },
        "rest_world_matrix": { "$ref": "#/$defs/mat4" },
        "rest_world_translation_m": { "$ref": "#/$defs/vec3" },
        "rest_world_linear": { "$ref": "#/$defs/linear_transform" },
        "rest_world_matrix_unavailable_reason": { "enum": ["non_finite_local_rest", "parent_rest_world_unavailable", "non_finite_world_matrix"] }
      },
      "oneOf": [
        {
          "required": ["rest_world_matrix", "rest_world_translation_m"],
          "not": { "required": ["rest_world_matrix_unavailable_reason"] },
          "properties": {
            "rest_world_linear": { "$ref": "#/$defs/finite_linear_transform" }
          }
        },
        {
          "required": ["rest_world_matrix_unavailable_reason"],
          "not": { "anyOf": [{ "required": ["rest_world_matrix"] }, { "required": ["rest_world_translation_m"] }] },
          "properties": {
            "rest_world_linear": {
              "allOf": [
                { "$ref": "#/$defs/linear_transform" },
                { "properties": { "classification": { "const": "non_finite" } } }
              ]
            }
          }
        }
      ],
      "additionalProperties": false
    },
    "local_rest": {
      "type": "object",
      "required": ["kind"],
      "properties": {
        "kind": { "enum": ["trs", "matrix", "unavailable"] },
        "translation_parent_space_m": { "$ref": "#/$defs/vec3" },
        "rotation_xyzw": { "$ref": "#/$defs/vec4" },
        "scale": { "$ref": "#/$defs/vec3" },
        "matrix": { "$ref": "#/$defs/mat4" },
        "reason": { "const": "non_finite_transform" }
      },
      "oneOf": [
        { "properties": { "kind": { "const": "trs" } }, "required": ["translation_parent_space_m", "rotation_xyzw", "scale"], "not": { "anyOf": [{ "required": ["matrix"] }, { "required": ["reason"] }] } },
        { "properties": { "kind": { "const": "matrix" } }, "required": ["matrix"], "not": { "anyOf": [{ "required": ["translation_parent_space_m"] }, { "required": ["rotation_xyzw"] }, { "required": ["scale"] }, { "required": ["reason"] }] } },
        { "properties": { "kind": { "const": "unavailable" } }, "required": ["reason"], "not": { "anyOf": [{ "required": ["translation_parent_space_m"] }, { "required": ["rotation_xyzw"] }, { "required": ["scale"] }, { "required": ["matrix"] }] } }
      ],
      "additionalProperties": false
    },
    "linear_transform": {
      "type": "object",
      "required": ["classification"],
      "properties": {
        "classification": { "enum": ["unit_orthonormal", "uniform_scaled", "non_uniform", "sheared", "reflected", "singular", "non_finite"] },
        "axis_lengths": { "$ref": "#/$defs/non_negative_vec3" },
        "determinant": { "type": "number" },
        "orientation": { "enum": ["positive", "negative", "zero"] },
        "uniform_scale": { "type": "number", "minimum": 0 }
      },
      "oneOf": [
        {
          "properties": { "classification": { "const": "non_finite" } },
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}