onnx.proto

//
// WARNING: This file is automatically generated!  Please edit onnx.in.proto.
//


// Copyright (c) Facebook Inc. and Microsoft Corporation.
// Licensed under the MIT license.

syntax = "proto2";

package onnx;

// Note [Release]
// We are still in the very early stage of defining ONNX. The current
// version of ONNX is a starting point. While we are actively working
// towards a complete spec, we would like to get the community involved
// by sharing our working version of ONNX.

// Note [Protobuf compatibility]
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// Based on experience working with downstream vendors, we generally can't
// assume recent versions of protobufs. This means that we do not use any
// protobuf features that are only available in proto3.
//
// Here are the most notable contortions we have to carry out to work around
// these limitations:
//
//   - No 'map' (added protobuf 3.0). We instead represent mappings as lists
//     of key-value pairs, where order does not matter and duplicates
//     are not allowed.

// Note [Namespaces]
// ~~~~~~~~~~~~~~~~~
// ONNX gives explicit names to graphs, intermediate values and
// serialized tensors.  To make it easier to generate names, we organize
// these into separate namespaces (so, e.g., a graph can have the same
// name as a serialized tensor.)  The namespaces are as follows:
//
// - Node: These names identify specific nodes in the graph (but not, necessarily
//   any particular input or output of the node.
// - Graph: These names identify graphs in the protobuf.
// - Attribute: These names identify attribute names for extra attributes that
//   are passed to operators.
// - Operator: These names identify particular operators.
// - Value: These names identify intermediate values (typically tensors) flowing through
//   the computation of a graph.
// - Shape: These names represent parameters for unknown shape dimensions.
//
// We specify the namespace of a name in ONNX as comments in the form
// of "namespace {Node,Graph,Operator,Attribute,Value,Shape}". Framework is responsible
// for supporting the namespaces.
//
// Naming things is hard. Every element with a name has an optional doc_string associated
// with it, providing a human-readable description in text markdown.

// To be compatible with both proto2 and proto3, we will use a version number
// that is not defined by the default value but an explicit enum number.
enum Version {
  // proto3 requires the first enum value to be zero.
  // We add this just to appease the compiler.
  _START_VERSION = 0;
  // The version field is always serialized and we will use it to store the
  // version that the  graph is generated from. This helps us set up version
  // control. We should use version as
  //     xx(major) - xx(minor) - xxxx(bugfix)
  // and we are starting with 0x00000001 (0.0.1), which was the
  //  version we published on Oct 10, 2017.
  IR_VERSION_2017_10_10 = 0x00000001;

  // IR_VERSION 0.0.2 published on Oct 30, 2017
  // - Added type discriminator to AttributeProto to support proto3 users
  IR_VERSION_2017_10_30 = 0x00000002;

  // IR VERSION 0.0.3 published on Nov 3, 2017
  // - For operator versioning:
  //    - Added new message OperatorSetIdProto
  //    - Added opset_import in ModelProto
  // - For vendor extensions, added domain in NodeProto
  IR_VERSION = 0x00000003;
}

// A named attribute containing either singular float, integer, string
// and tensor values, or repeated float, integer, string and tensor values.
// An AttributeProto MUST contain the name field, and *only one* of the
// following content fields, effectively enforcing a C/C++ union equivalent.
message AttributeProto {

  // Note: this enum is structurally identical to the OpSchema::AttrType
  // enum defined in schema.h.  If you rev one, you likely need to rev the other.
  enum AttributeType {
    UNDEFINED = 0;
    FLOAT = 1;
    INT = 2;
    STRING = 3;
    TENSOR = 4;
    GRAPH = 5;

    FLOATS = 6;
    INTS = 7;
    STRINGS = 8;
    TENSORS = 9;
    GRAPHS = 10;
  }

  // The name field MUST be present for this version of the IR.
  optional string name = 1;           // namespace Attribute

  // A human-readable documentation for this attribute. Markdown is allowed.
  optional string doc_string = 13;

  // The type field MUST be present for this version of the IR.
  // For 0.0.1 versions of the IR, this field was not defined, and
  // implementations needed to use has_field hueristics to determine
  // which value field was in use.  For IR_VERSION 0.0.2 or later, this
  // field MUST be set and match the f|i|s|t|... field in use.  This
  // change was made to accomodate proto3 implementations.
  optional AttributeType type = 20;   // discriminator that indicates which field below is in use

  // Exactly ONE of the following fields must be present for this version of the IR
  optional float f = 2;               // float
  optional int64 i = 3;               // int
  optional bytes s = 4;               // UTF-8 string
  optional TensorProto t = 5;         // tensor value
  optional GraphProto g = 6;          // graph
  // Do not use field below, it's deprecated.
  // optional ValueProto v = 12;         // value - subsumes everything but graph

  repeated float floats = 7;          // list of floats
  repeated int64 ints = 8;            // list of ints
  repeated bytes strings = 9;         // list of UTF-8 strings
  repeated TensorProto tensors = 10;  // list of tensors
  repeated GraphProto graphs = 11;    // list of graph
}

// Defines information on value, including the name, the type, and
// the shape of the value.
message ValueInfoProto {
  // This field MUST be present in this version of the IR.
  optional string name = 1;     // namespace Value
  // This field MUST be present in this version of the IR.
  optional TypeProto type = 2;
  // A human-readable documentation for this value. Markdown is allowed.
  optional string doc_string = 3;
}

// NodeProto stores a node that is similar to the notion of "layer"
// or "operator" in many deep learning frameworks. For example, it can be a
// node of type "Conv" that takes in an image, a filter tensor and a bias
// tensor, and produces the convolved output.
message NodeProto {
  repeated string input = 1;    // namespace Value
  repeated string output = 2;   // namespace Value

  // An optional identifier for this node in a graph.
  // This field MAY be absent in ths version of the IR.
  optional string name = 3;     // namespace Node

  // The symbolic identifier of the Operator to execute.
  optional string op_type = 4;  // namespace Operator
  // The domain of the OperatorSet that specifies the operator named by op_type.
  optional string domain = 7;   // namespace Domain

  // Additional named attributes.
  // NOTE: Simply using ValueProto.NameValuePairProto is the most general
  //       solution.  I kept AttributeProto to minimize churn on CI results.
  repeated AttributeProto attribute = 5;

  // A human-readable documentation for this node. Markdown is allowed.
  optional string doc_string = 6;
}

// ModelProto is a top-level file/container format for bundling a ML model.
// The semantics of the model are described by the GraphProto that represents
// a parameterized computation graph against a set of named operators that are
// defined independently from the graph.
message ModelProto {
  // The version of the IR this model targets. See Version enum above.
  // This field MUST be present.
  optional int64 ir_version = 1;

  // The OperatorSets this model relies on.
  // All ModelProtos MUST have at least one entry that
  // specifies which version of the ONNX OperatorSet is
  // being imported.
  //
  // All nodes in the ModelProto's graph will bind against the operator
  // with the same-domain/same-op_type operator with the HIGHEST version
  // in the referenced operator sets.
  repeated OperatorSetIdProto opset_import = 8;

  // The name of the framework or tool used to generate this model.
  // This field SHOULD be present to indicate which implementation/tool/framework
  // emitted the model.
  optional string producer_name = 2;

  // The version of the framework or tool used to generate this model.
  // This field SHOULD be present to indicate which implementation/tool/framework
  // emitted the model.
  optional string producer_version = 3;

  // Domain name of the model.
  // We use reverse domain names as name space indicators. For example:
  // `com.facebook.fair` or `com.microsoft.cognitiveservices`
  //
  // Together with `model_version` and GraphProto.name, this forms the unique identity of
  // the graph.
  optional string domain = 4;

  // The version of the graph encoded. See Version enum below.
  optional int64 model_version = 5;

  // A human-readable documentation for this model. Markdown is allowed.
  optional string doc_string = 6;

  // The parameterized graph that is evaluated to execute the model.
  optional GraphProto graph = 7;

  // Named metadata values; keys should be distinct.
  repeated StringStringEntryProto metadata_props = 14;
};

// StringStringEntryProto follows the pattern for cross-proto-version maps.
// See https://developers.google.com/protocol-buffers/docs/proto3#maps
message StringStringEntryProto {
  optional string key = 1;
  optional string value= 2;
};

// GraphProto defines a parameterized series of nodes to form a directed acyclic graph.
// This is the equivalent of the "network" and "graph" in many deep learning
// frameworks.
message GraphProto {
  // The nodes in the graph.
  repeated NodeProto node = 1;

  // The name of the graph.
  optional string name = 2;   // namespace Graph

  // A list of named tensor values (constants), used to specify default
  // values for some of the inputs of the graph.
  // Each TensorProto entry must have a distinct name (within the list) that
  // also appears in the input list.
  // In an evaluation, the default value specified here is used if and only if
  // user specifies no value for the corresponding input parameter.
  // May be used to pass serialized parameters for networks.
  repeated TensorProto initializer = 5;

  // A human-readable documentation for this graph. Markdown is allowed.
  optional string doc_string = 10;

  // The inputs and outputs of the graph.
  repeated ValueInfoProto input = 11;
  repeated ValueInfoProto output = 12;

  // Information for the values in the graph. The ValueInfoProto.name's
  // must be distinct. It is optional for a value to appear in value_info list.
  repeated ValueInfoProto value_info = 13;

  // DO NOT USE the following fields, they were deprecated before
  // repeated string input = 3;
  // repeated string output = 4;
  // optional int64 ir_version = 6;
  // optional int64 producer_version = 7;
  // optional string producer_tag = 8;
  // optional string domain = 9;
}

// A message defined to store a tensor in its serialized format.
message TensorProto {
  enum DataType {
    UNDEFINED = 0;
    // Basic types.
    FLOAT = 1;   // float
    UINT8 = 2;   // uint8_t
    INT8 = 3;    // int8_t
    UINT16 = 4;  // uint16_t
    INT16 = 5;   // int16_t
    INT32 = 6;   // int32_t
    INT64 = 7;   // int64_t
    STRING = 8;  // string
    BOOL = 9;    // bool

    // Advanced types
    FLOAT16 = 10;
    DOUBLE = 11;
    UINT32 = 12;
    UINT64 = 13;
    COMPLEX64 = 14;     // complex with float32 real and imaginary components
    COMPLEX128 = 15;    // complex with float64 real and imaginary components
    // Future extensions go here.
  }

  // The shape of the tensor.
  repeated int64 dims = 1;

  // The data type of the tensor.
  optional DataType data_type = 2;

  // For very large tensors, we may want to store them in chunks, in which
  // case the following fields will specify the segment that is stored in
  // the current TensorProto.
  message Segment {
    optional int64 begin = 1;
    optional int64 end = 2;
  }
  optional Segment segment = 3;

  // Tensor content must be in the row major order.
  //
  // Depending on the data_type field, exactly one of the fields below with
  // name ending in _data is used to store the elements of the tensor.

  // For float and complex64 values
  // Complex64 tensors are encoded as a single array of floats,
  // with the real components appearing in odd numbered positions,
  // and the corresponding imaginary component apparing in the
  // subsequent even numbered position. (e.g., [1.0 + 2.0i, 3.0 + 4.0i]
  // is encoded as [1.0, 2.0 ,3.0 ,4.0]
  // When this field is present, the data_type field MUST be FLOAT or COMPLEX64.
  repeated float float_data = 4 [packed = true];

  // For int32, uint8, int8, uint16, int16, bool, and float16 values
  // float16 values must be bit-wise converted to an uint16_t prior
  // to writing to the buffer.
  // When this field is present, the data_type field MUST be
  // INT32, INT16, INT8, UINT16, INT8, BOOL, or FLOAT32
  repeated int32 int32_data = 5 [packed = true];

  // For strings.
  // Each element of string_data is a UTF-8 encoded Unicode
  // string. No trailing null, no leading BOM. The protobuf "string"
  // scalar type is not used to match ML community conventions.
  // When this field is present, the data_type field MUST be STRING
  repeated bytes string_data = 6;

  // For int64.
  // When this field is present, the data_type field MUST be INT64
  repeated int64 int64_data = 7 [packed = true];

  // Optionally, a name for the tensor.
  optional string name = 8; // namespace Value

  // A human-readable documentation for this tensor. Markdown is allowed.
  optional string doc_string = 12;

  // Serializations can either use one of the fields above, or use this
  // raw bytes field. The only exception is the string case, where one is
  // required to store the content in the repeated bytes string_data field.
  //
  // When this raw_data field is used to store tensor value, elements MUST
  // be stored in as fixed-width, little-endian order.
  // Floating-point data types MUST be stored in IEEE 754 format.
  // Complex64 elements must be written as two consecutive FLOAT values, real component first.
  // Complex128 elements must be written as two consecutive DOUBLE values, real component first.
  // Boolean type MUST be written one byte per tensor element (00000001 for true, 00000000 for false).
  //
  // Note: the advantage of specific field rather than the raw_data field is
  // that in some cases (e.g. int data), protobuf does a better packing via
  // variable length storage, and may lead to smaller binary footprint.
  // When this field is present, the data_type field MUST NOT be STRING or UNDEFINED
  optional bytes raw_data = 9;

  // For double
  // Complex64 tensors are encoded as a single array of doubles,
  // with the real components appearing in odd numbered positions,
  // and the corresponding imaginary component apparing in the
  // subsequent even numbered position. (e.g., [1.0 + 2.0i, 3.0 + 4.0i]
  // is encoded as [1.0, 2.0 ,3.0 ,4.0]
  // When this field is present, the data_type field MUST be DOUBLE or COMPLEX128
  repeated double double_data = 10 [packed = true];

  // For uint64 and uint32 values
  // When this field is present, the data_type field MUST be
  // UINT32 or UINT64
  repeated uint64 uint64_data = 11 [packed = true];
}

// Defines a tensor shape. A dimension can be either an integer value
// or a symbolic variable. A symbolic variable represents an unknown
// dimension.
message TensorShapeProto {
  message Dimension {
    oneof value {
      int64 dim_value = 1;
      string dim_param = 2;   // namespace Shape
    };
  };
  repeated Dimension dim = 1;
}

// Define the types.
message TypeProto {

  message Tensor {
    // This field MUST NOT have the value of UNDEFINED
    // This field MUST be present for this version of the IR.
    optional TensorProto.DataType elem_type = 1;
    optional TensorShapeProto shape = 2;
  }


  oneof value {
    // The type of a tensor.
    Tensor tensor_type = 1;

  }
}

// OperatorSets are uniquely identified by a (domain, opset_version) pair.
message OperatorSetIdProto {
  // The domain of the operator set being identified.
  // The empty string ("") or absence of this field implies the operator
  // set that is defined as part of the ONNX specification.
  // This field MUST be present in this version of the IR when referring to any other operator set.
  optional string domain = 1;

  // The version of the operator set being identified.
  // This field MUST be present in this version of the IR.
  optional int64 version = 2;
}