TensorFlow C++ PNG to JPG converter static binary

BUILD

load("//tensorflow:tensorflow.bzl", "tf_cc_binary")

tf_cc_binary(
    name = "png2jpg",
    srcs = ["png2jpg.cc"],
    linkstatic = 1,
    deps = [
        "//tensorflow/cc:cc_ops",
        "//tensorflow/cc:client_session",
        "//tensorflow/cc:scope",
        "//tensorflow/core:direct_session",
        "//tensorflow/core:framework",
        "//tensorflow/core:lib",
        "//tensorflow/core/kernels:constant_op",
        "//tensorflow/core/kernels:decode_image_op",
        "//tensorflow/core/kernels:encode_jpeg_op",
    ],
)

png2jpg.cc

#include <iostream>
#include <vector>
#include "tensorflow/cc/client/client_session.h"
#include "tensorflow/cc/ops/array_ops.h"
#include "tensorflow/cc/ops/image_ops.h"
#include "tensorflow/core/framework/tensor.h"
#include "tensorflow/core/lib/core/errors.h"
#include "tensorflow/core/lib/core/status.h"

using namespace tensorflow;

static Status ConvertPngToJpg(const string& png, string* jpg) {
  Scope root = Scope::NewRootScope();
  ClientSession session(root);
  auto x = ops::Placeholder(root, DT_STRING);
  auto decode_png = ops::DecodePng(root, x);
  auto encode_jpg = ops::EncodeJpeg(root, decode_png);
  Tensor t(DT_STRING, TensorShape({}));
  t.scalar<string>()() = png;
  std::vector<Tensor> outputs;
  TF_RETURN_IF_ERROR(session.Run({{x, t}}, {encode_jpg}, &outputs));
  *jpg = outputs[0].scalar<string>()();
  return Status::OK();
}

int main(int argc, char* argv[]) {
  if (argc != 1) {
    std::cerr << "Usage: " << argv[0] << " <foo.png >bar.jpg" << std::endl;
    return 1;
  }
  std::ostringstream png;
  png << std::cin.rdbuf();
  string jpg;
  Status s = ConvertPngToJpg(png.str(), &jpg);
  if (!s.ok()) {
    std::cerr << s << std::endl;
    return 1;
  }
  std::cout << jpg;
  return 0;
}