4_asynchronous_loop_custom_input_and_output.cpp

// ------------------------- OpenPose C++ API Tutorial - Example 4 - Custom Input and Output -------------------------
// Asynchronous mode: ideal for fast prototyping when performance is not an issue. The user emplaces/pushes and pops frames from the OpenPose wrapper
// when he desires to.

// This example shows the user how to use the OpenPose wrapper class:
    // 1. User reads images
    // 2. Extract and render keypoint / heatmap / PAF of that image
    // 3. Save the results on disk
    // 4. User displays the rendered pose
    // Everything in a multi-thread scenario
// In addition to the previous OpenPose modules, we also need to use:
    // 1. `core` module:
        // For the Array<float> class that the `pose` module needs
        // For the Datum struct that the `thread` module sends between the queues
    // 2. `utilities` module: for the error & logging functions, i.e., op::error & op::log respectively
// This file should only be used for the user to take specific examples.

// Command-line user intraface
#define OPENPOSE_FLAGS_DISABLE_PRODUCER
#define OPENPOSE_FLAGS_DISABLE_DISPLAY
#include <openpose/flags.hpp>
// OpenPose dependencies
#include <openpose/headers.hpp>

// Custom OpenPose flags
// Producer
DEFINE_string(image_dir, "examples/media/",
    "Process a directory of images. Read all standard formats (jpg, png, bmp, etc.).");

// If the user needs his own variables, he can inherit the op::Datum struct and add them in there.
// UserDatum can be directly used by the OpenPose wrapper because it inherits from op::Datum, just define
// WrapperT<std::vector<std::shared_ptr<UserDatum>>> instead of Wrapper
// (or equivalently WrapperT<std::vector<std::shared_ptr<UserDatum>>>)
struct UserDatum : public op::Datum
{
    bool boolThatUserNeedsForSomeReason;

    UserDatum(const bool boolThatUserNeedsForSomeReason_ = false) :
        boolThatUserNeedsForSomeReason{boolThatUserNeedsForSomeReason_}
    {}
};

// The W-classes can be implemented either as a template or as simple classes given
// that the user usually knows which kind of data he will move between the queues,
// in this case we assume a std::shared_ptr of a std::vector of UserDatum

// This worker will just read and return all the jpg files in a directory
class UserInputClass
{
public:
    UserInputClass(const std::string& directoryPath) :
        mImageFiles{op::getFilesOnDirectory(directoryPath, "jpg")},
        // If we want "jpg" + "png" images
        // mImageFiles{op::getFilesOnDirectory(directoryPath, std::vector<std::string>{"jpg", "png"})},
        mCounter{0},
        mClosed{false}
    {
        if (mImageFiles.empty())
            op::error("No images found on: " + directoryPath, __LINE__, __FUNCTION__, __FILE__);
    }

    std::shared_ptr<std::vector<std::shared_ptr<UserDatum>>> createDatum()
    {
        // Close program when empty frame
        if (mClosed || mImageFiles.size() <= mCounter)
        {
            op::log("Last frame read and added to queue. Closing program after it is processed.", op::Priority::High);
            // This funtion stops this worker, which will eventually stop the whole thread system once all the frames
            // have been processed
            mClosed = true;
            return nullptr;
        }
        else // if (!mClosed)
        {
            // Create new datum
            auto datumsPtr = std::make_shared<std::vector<std::shared_ptr<UserDatum>>>();
            datumsPtr->emplace_back();
            auto& datumPtr = datumsPtr->at(0);
            datumPtr = std::make_shared<UserDatum>();

            // Fill datum
            datumPtr->cvInputData = cv::imread(mImageFiles.at(mCounter++));

            // If empty frame -> return nullptr
            if (datumPtr->cvInputData.empty())
            {
                op::log("Empty frame detected on path: " + mImageFiles.at(mCounter-1) + ". Closing program.",
                        op::Priority::High);
                mClosed = true;
                datumsPtr = nullptr;
            }

            return datumsPtr;
        }
    }

    bool isFinished() const
    {
        return mClosed;
    }

private:
    const std::vector<std::string> mImageFiles;
    unsigned long long mCounter;
    bool mClosed;
};

// This worker will just read and return all the jpg files in a directory
class UserOutputClass
{
public:
    bool display(const std::shared_ptr<std::vector<std::shared_ptr<UserDatum>>>& datumsPtr)
    {
        // User's displaying/saving/other processing here
            // datumPtr->cvOutputData: rendered frame with pose or heatmaps
            // datumPtr->poseKeypoints: Array<float> with the estimated pose
        char key = ' ';
        if (datumsPtr != nullptr && !datumsPtr->empty())
        {
            cv::imshow("User worker GUI", datumsPtr->at(0)->cvOutputData);
            // Display image and sleeps at least 1 ms (it usually sleeps ~5-10 msec to display the image)
            key = (char)cv::waitKey(1);
        }
        else
            op::log("Nullptr or empty datumsPtr found.", op::Priority::High, __LINE__, __FUNCTION__, __FILE__);
        return (key == 27);
    }
    void printKeypoints(const std::shared_ptr<std::vector<std::shared_ptr<UserDatum>>>& datumsPtr)
    {
        // Example: How to use the pose keypoints
        if (datumsPtr != nullptr && !datumsPtr->empty())
        {
            op::log("\nKeypoints:");
            // Accesing each element of the keypoints
            const auto& poseKeypoints = datumsPtr->at(0)->poseKeypoints;
            op::log("Person pose keypoints:");
            for (auto person = 0 ; person < poseKeypoints.getSize(0) ; person++)
            {
                op::log("Person " + std::to_string(person) + " (x, y, score):");
                for (auto bodyPart = 0 ; bodyPart < poseKeypoints.getSize(1) ; bodyPart++)
                {
                    std::string valueToPrint;
                    for (auto xyscore = 0 ; xyscore < poseKeypoints.getSize(2) ; xyscore++)
                        valueToPrint += std::to_string(   poseKeypoints[{person, bodyPart, xyscore}]   ) + " ";
                    op::log(valueToPrint);
                }
            }
            op::log(" ");
            // Alternative: just getting std::string equivalent
            op::log("Face keypoints: " + datumsPtr->at(0)->faceKeypoints.toString());
            op::log("Left hand keypoints: " + datumsPtr->at(0)->handKeypoints[0].toString());
            op::log("Right hand keypoints: " + datumsPtr->at(0)->handKeypoints[1].toString());
            // Heatmaps
            const auto& poseHeatMaps = datumsPtr->at(0)->poseHeatMaps;
            if (!poseHeatMaps.empty())
            {
                op::log("Pose heatmaps size: [" + std::to_string(poseHeatMaps.getSize(0)) + ", "
                        + std::to_string(poseHeatMaps.getSize(1)) + ", "
                        + std::to_string(poseHeatMaps.getSize(2)) + "]");
                const auto& faceHeatMaps = datumsPtr->at(0)->faceHeatMaps;
                op::log("Face heatmaps size: [" + std::to_string(faceHeatMaps.getSize(0)) + ", "
                        + std::to_string(faceHeatMaps.getSize(1)) + ", "
                        + std::to_string(faceHeatMaps.getSize(2)) + ", "
                        + std::to_string(faceHeatMaps.getSize(3)) + "]");
                const auto& handHeatMaps = datumsPtr->at(0)->handHeatMaps;
                op::log("Left hand heatmaps size: [" + std::to_string(handHeatMaps[0].getSize(0)) + ", "
                        + std::to_string(handHeatMaps[0].getSize(1)) + ", "
                        + std::to_string(handHeatMaps[0].getSize(2)) + ", "
                        + std::to_string(handHeatMaps[0].getSize(3)) + "]");
                op::log("Right hand heatmaps size: [" + std::to_string(handHeatMaps[1].getSize(0)) + ", "
                        + std::to_string(handHeatMaps[1].getSize(1)) + ", "
                        + std::to_string(handHeatMaps[1].getSize(2)) + ", "
                        + std::to_string(handHeatMaps[1].getSize(3)) + "]");
            }
        }
        else
            op::log("Nullptr or empty datumsPtr found.", op::Priority::High, __LINE__, __FUNCTION__, __FILE__);
    }
};

int tutorialApiCpp4()
{
    try
    {
        op::log("Starting OpenPose demo...", op::Priority::High);
        const auto timerBegin = std::chrono::high_resolution_clock::now();

        // logging_level
        op::check(0 <= FLAGS_logging_level && FLAGS_logging_level <= 255, "Wrong logging_level value.",
                  __LINE__, __FUNCTION__, __FILE__);
        op::ConfigureLog::setPriorityThreshold((op::Priority)FLAGS_logging_level);
        op::Profiler::setDefaultX(FLAGS_profile_speed);

        // Applying user defined configuration - GFlags to program variables
        // outputSize
        const auto outputSize = op::flagsToPoint(FLAGS_output_resolution, "-1x-1");
        // netInputSize
        const auto netInputSize = op::flagsToPoint(FLAGS_net_resolution, "-1x368");
        // faceNetInputSize
        const auto faceNetInputSize = op::flagsToPoint(FLAGS_face_net_resolution, "368x368 (multiples of 16)");
        // handNetInputSize
        const auto handNetInputSize = op::flagsToPoint(FLAGS_hand_net_resolution, "368x368 (multiples of 16)");
        // poseModel
        const auto poseModel = op::flagsToPoseModel(FLAGS_model_pose);
        // JSON saving
        if (!FLAGS_write_keypoint.empty())
            op::log("Flag `write_keypoint` is deprecated and will eventually be removed."
                    " Please, use `write_json` instead.", op::Priority::Max);
        // keypointScale
        const auto keypointScale = op::flagsToScaleMode(FLAGS_keypoint_scale);
        // heatmaps to add
        const auto heatMapTypes = op::flagsToHeatMaps(FLAGS_heatmaps_add_parts, FLAGS_heatmaps_add_bkg,
                                                      FLAGS_heatmaps_add_PAFs);
        const auto heatMapScale = op::flagsToHeatMapScaleMode(FLAGS_heatmaps_scale);
        // >1 camera view?
        const auto multipleView = (FLAGS_3d || FLAGS_3d_views > 1);
        // Enabling Google Logging
        const bool enableGoogleLogging = true;

        // Configuring OpenPose
        op::log("Configuring OpenPose...", op::Priority::High);
        op::WrapperT<UserDatum> opWrapperT{op::ThreadManagerMode::Asynchronous};
        // Pose configuration (use WrapperStructPose{} for default and recommended configuration)
        const op::WrapperStructPose wrapperStructPose{
            !FLAGS_body_disable, netInputSize, outputSize, keypointScale, FLAGS_num_gpu, FLAGS_num_gpu_start,
            FLAGS_scale_number, (float)FLAGS_scale_gap, op::flagsToRenderMode(FLAGS_render_pose, multipleView),
            poseModel, !FLAGS_disable_blending, (float)FLAGS_alpha_pose, (float)FLAGS_alpha_heatmap,
            FLAGS_part_to_show, FLAGS_model_folder, heatMapTypes, heatMapScale, FLAGS_part_candidates,
            (float)FLAGS_render_threshold, FLAGS_number_people_max, FLAGS_maximize_positives, FLAGS_fps_max,
            FLAGS_prototxt_path, FLAGS_caffemodel_path, enableGoogleLogging};
        opWrapperT.configure(wrapperStructPose);
        // Face configuration (use op::WrapperStructFace{} to disable it)
        const op::WrapperStructFace wrapperStructFace{
            FLAGS_face, faceNetInputSize, op::flagsToRenderMode(FLAGS_face_render, multipleView, FLAGS_render_pose),
            (float)FLAGS_face_alpha_pose, (float)FLAGS_face_alpha_heatmap, (float)FLAGS_face_render_threshold};
        opWrapperT.configure(wrapperStructFace);
        // Hand configuration (use op::WrapperStructHand{} to disable it)
        const op::WrapperStructHand wrapperStructHand{
            FLAGS_hand, handNetInputSize, FLAGS_hand_scale_number, (float)FLAGS_hand_scale_range, FLAGS_hand_tracking,
            op::flagsToRenderMode(FLAGS_hand_render, multipleView, FLAGS_render_pose), (float)FLAGS_hand_alpha_pose,
            (float)FLAGS_hand_alpha_heatmap, (float)FLAGS_hand_render_threshold};
        opWrapperT.configure(wrapperStructHand);
        // Extra functionality configuration (use op::WrapperStructExtra{} to disable it)
        const op::WrapperStructExtra wrapperStructExtra{
            FLAGS_3d, FLAGS_3d_min_views, FLAGS_identification, FLAGS_tracking, FLAGS_ik_threads};
        opWrapperT.configure(wrapperStructExtra);
        // Output (comment or use default argument to disable any output)
        const op::WrapperStructOutput wrapperStructOutput{
            FLAGS_cli_verbose, FLAGS_write_keypoint, op::stringToDataFormat(FLAGS_write_keypoint_format),
            FLAGS_write_json, FLAGS_write_coco_json, FLAGS_write_coco_foot_json, FLAGS_write_coco_json_variant,
            FLAGS_write_images, FLAGS_write_images_format, FLAGS_write_video, FLAGS_write_video_fps,
            FLAGS_write_heatmaps, FLAGS_write_heatmaps_format, FLAGS_write_video_3d, FLAGS_write_video_adam,
            FLAGS_write_bvh, FLAGS_udp_host, FLAGS_udp_port};
        opWrapperT.configure(wrapperStructOutput);
        // No GUI. Equivalent to: opWrapper.configure(op::WrapperStructGui{});
        // Set to single-thread (for sequential processing and/or debugging and/or reducing latency)
        if (FLAGS_disable_multi_thread)
            opWrapperT.disableMultiThreading();

        // Start, run, and stop processing - exec() blocks this thread until OpenPose wrapper has finished
        op::log("Starting thread(s)...", op::Priority::High);
        opWrapperT.start();

        // User processing
        UserInputClass userInputClass(FLAGS_image_dir);
        UserOutputClass userOutputClass;
        bool userWantsToExit = false;
        while (!userWantsToExit && !userInputClass.isFinished())
        {
            // Push frame
            auto datumToProcess = userInputClass.createDatum();
            if (datumToProcess != nullptr)
            {
                auto successfullyEmplaced = opWrapperT.waitAndEmplace(datumToProcess);
                // Pop frame
                std::shared_ptr<std::vector<std::shared_ptr<UserDatum>>> datumProcessed;
                if (successfullyEmplaced && opWrapperT.waitAndPop(datumProcessed))
                {
                    userWantsToExit = userOutputClass.display(datumProcessed);
                    userOutputClass.printKeypoints(datumProcessed);
                }
                else
                    op::log("Processed datum could not be emplaced.", op::Priority::High,
                            __LINE__, __FUNCTION__, __FILE__);
            }
        }

        op::log("Stopping thread(s)", op::Priority::High);
        opWrapperT.stop();

        // Measuring total time
        const auto now = std::chrono::high_resolution_clock::now();
        const auto totalTimeSec = (double)std::chrono::duration_cast<std::chrono::nanoseconds>(now-timerBegin).count()
                                * 1e-9;
        const auto message = "OpenPose demo successfully finished. Total time: "
                           + std::to_string(totalTimeSec) + " seconds.";
        op::log(message, op::Priority::High);

        // Return successful message
        return 0;
    }
    catch (const std::exception& e)
    {
        return -1;
    }
}

int main(int argc, char *argv[])
{
    // Parsing command line flags
    gflags::ParseCommandLineFlags(&argc, &argv, true);

    // Running tutorialApiCpp4
    return tutorialApiCpp4();
}