Introduce Stream/SidePacket aliases for Source/SideSource

PiperOrigin-RevId: 486761126
This commit is contained in:
MediaPipe Team 2022-11-07 14:16:29 -08:00 committed by Copybara-Service
parent e994efd40f
commit 51dbd9779c

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@ -1,8 +1,10 @@
#ifndef MEDIAPIPE_FRAMEWORK_API2_BUILDER_H_
#define MEDIAPIPE_FRAMEWORK_API2_BUILDER_H_
#include <memory>
#include <string>
#include <type_traits>
#include <vector>
#include "absl/container/btree_map.h"
#include "absl/strings/string_view.h"
@ -74,6 +76,7 @@ class TagIndexMap {
class Graph;
class NodeBase;
class PacketGenerator;
// These structs are used internally to store information about the endpoints
// of a connection.
@ -146,6 +149,7 @@ template <bool IsSide, typename T>
class SourceImpl {
public:
using Base = SourceBase;
using PayloadT = T;
// Src is used as the return type of fluent methods below. Since these are
// single-port methods, it is desirable to always decay to a reference to the
@ -201,10 +205,61 @@ class SourceImpl {
// when building the graph.
template <typename T = internal::Generic>
using Source = SourceImpl<false, T>;
// Represents a stream of packets of a particular type.
//
// The intended use:
// - decouple input/output streams from graph/node during graph construction
// - pass streams around and connect them as needed, extracting reusable parts
// to utility/convenience functions or classes.
//
// For example:
// Stream<Image> Resize(Stream<Image> image, const Size& size, Graph& graph) {
// auto& scaler_node = graph.AddNode("GlScalerCalculator");
// auto& opts = scaler_node.GetOptions<GlScalerCalculatorOptions>();
// opts.set_output_width(size.width);
// opts.set_output_height(size.height);
// a >> scaler_node.In("IMAGE");
// return scaler_node.Out("IMAGE").Cast<Image>();
// }
//
// Where graph can use it as:
// Graph graph;
// Stream<Image> input_image = graph.In("INPUT_IMAGE").Cast<Image>();
// Stream<Image> resized_image = Resize(input_image, {64, 64}, graph);
template <typename T>
using Stream = Source<T>;
template <typename T = internal::Generic>
using MultiSource = MultiPort<Source<T>>;
template <typename T = internal::Generic>
using SideSource = SourceImpl<true, T>;
// Represents a side packet of a particular type.
//
// The intended use:
// - decouple input/output side packets from graph/node during graph
// construction
// - pass side packets around and connect them as needed, extracting reusable
// parts utility/convenience functions or classes.
//
// For example:
// SidePacket<TfLiteModelPtr> GetModel(SidePacket<std::string> model_blob,
// Graph& graph) {
// auto& model_node = graph.AddNode("TfLiteModelCalculator");
// model_blob >> model_node.SideIn("MODEL_BLOB");
// return model_node.SideOut("MODEL").Cast<TfLiteModelPtr>();
// }
//
// Where graph can use it as:
// Graph graph;
// SidePacket<std::string> model_blob =
// graph.SideIn("MODEL_BLOB").Cast<std::string>();
// SidePacket<TfLiteModelPtr> model = GetModel(model_blob, graph);
template <typename T>
using SidePacket = SideSource<T>;
template <typename T = internal::Generic>
using MultiSideSource = MultiPort<SideSource<T>>;