// Copyright 2019 The MediaPipe Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

syntax = "proto2";

package mediapipe;

import "mediapipe/framework/calculator.proto";

// Options to generate anchors for SSD object detection models.
message SsdAnchorsCalculatorOptions {
  extend mediapipe.CalculatorOptions {
    optional SsdAnchorsCalculatorOptions ext = 247258239;
  }
  // Size of input images.
  required int32 input_size_width = 1;
  required int32 input_size_height = 2;

  // Min and max scales for generating anchor boxes on feature maps.
  required float min_scale = 3;
  required float max_scale = 4;

  // The offset for the center of anchors. The value is in the scale of stride.
  // E.g. 0.5 meaning 0.5 * |current_stride| in pixels.
  required float anchor_offset_x = 5 [default = 0.5];
  required float anchor_offset_y = 6 [default = 0.5];

  // Number of output feature maps to generate the anchors on.
  required int32 num_layers = 7;
  // Sizes of output feature maps to create anchors. Either feature_map size or
  // stride should be provided.
  repeated int32 feature_map_width = 8;
  repeated int32 feature_map_height = 9;
  // Strides of each output feature maps.
  repeated int32 strides = 10;

  // List of different aspect ratio to generate anchors.
  repeated float aspect_ratios = 11;

  // A boolean to indicate whether the fixed 3 boxes per location is used in the
  // lowest layer.
  optional bool reduce_boxes_in_lowest_layer = 12 [default = false];
  // An additional anchor is added with this aspect ratio and a scale
  // interpolated between the scale for a layer and the scale for the next layer
  // (1.0 for the last layer). This anchor is not included if this value is 0.
  optional float interpolated_scale_aspect_ratio = 13 [default = 1.0];

  // Whether use fixed width and height (e.g. both 1.0f) for each anchor.
  // This option can be used when the predicted anchor width and height are in
  // pixels.
  optional bool fixed_anchor_size = 14 [default = false];
}