int main(int argc, const char **argv) {
    AppInput app_input = {0};
    FILE *outfile;
    vpx_codec_ctx_t codec;
    vpx_codec_enc_cfg_t enc_cfg;
    SvcContext svc_ctx;
    uint32_t i;
    uint32_t frame_cnt = 0;
    vpx_image_t raw;
    vpx_codec_err_t res;
    int pts = 0;            /* PTS starts at 0 */
    int frame_duration = 1; /* 1 timebase tick per frame */
    vpx_codec_cx_pkt_t packet = {0};
    packet.kind = VPX_CODEC_CX_FRAME_PKT;

    memset(&svc_ctx, 0, sizeof(svc_ctx));
    svc_ctx.log_print = 1;
    exec_name = argv[0];
    parse_command_line(argc, argv, &app_input, &svc_ctx, &enc_cfg);

    // Allocate image buffer
    if (!vpx_img_alloc(&raw, VPX_IMG_FMT_I420, enc_cfg.g_w, enc_cfg.g_h, 32))
        die("Failed to allocate image %dx%d\n", enc_cfg.g_w, enc_cfg.g_h);

    if (!(app_input.input_ctx.file = fopen(app_input.input_ctx.filename, "rb")))
        die("Failed to open %s for reading\n", app_input.input_ctx.filename);

    if (!(outfile = fopen(app_input.output_filename, "wb")))
        die("Failed to open %s for writing\n", app_input.output_filename);

    // Initialize codec
    if (vpx_svc_init(&svc_ctx, &codec, vpx_codec_vp9_cx(), &enc_cfg) !=
            VPX_CODEC_OK)
        die("Failed to initialize encoder\n");

    ivf_write_file_header(outfile, &enc_cfg, VP9_FOURCC, 0);

    // skip initial frames
    for (i = 0; i < app_input.frames_to_skip; ++i) {
        read_yuv_frame(&app_input.input_ctx, &raw);
    }

    // Encode frames
    while (frame_cnt < app_input.frames_to_code) {
        if (read_yuv_frame(&app_input.input_ctx, &raw)) break;

        res = vpx_svc_encode(&svc_ctx, &codec, &raw, pts, frame_duration,
                             VPX_DL_REALTIME);
        printf("%s", vpx_svc_get_message(&svc_ctx));
        if (res != VPX_CODEC_OK) {
            die_codec(&codec, "Failed to encode frame");
        }
        if (vpx_svc_get_frame_size(&svc_ctx) > 0) {
            packet.data.frame.pts = pts;
            packet.data.frame.sz = vpx_svc_get_frame_size(&svc_ctx);
            ivf_write_frame_header(outfile, &packet);
            (void)fwrite(vpx_svc_get_buffer(&svc_ctx), 1,
                         vpx_svc_get_frame_size(&svc_ctx), outfile);
        }
        ++frame_cnt;
        pts += frame_duration;
    }

    printf("Processed %d frames\n", frame_cnt);

    fclose(app_input.input_ctx.file);
    if (vpx_codec_destroy(&codec)) die_codec(&codec, "Failed to destroy codec");

    // rewrite the output file headers with the actual frame count, and
    // resolution of the highest layer
    if (!fseek(outfile, 0, SEEK_SET)) {
        // get resolution of highest layer
        if (VPX_CODEC_OK != vpx_svc_get_layer_resolution(&svc_ctx,
                svc_ctx.spatial_layers - 1,
                &enc_cfg.g_w,
                &enc_cfg.g_h)) {
            die("Failed to get output resolution");
        }
        ivf_write_file_header(outfile, &enc_cfg, VP9_FOURCC, frame_cnt);
    }
    fclose(outfile);
    vpx_img_free(&raw);

    // display average size, psnr
    printf("%s", vpx_svc_dump_statistics(&svc_ctx));

    vpx_svc_release(&svc_ctx);

    return EXIT_SUCCESS;
}
int main(int argc, const char **argv) {
  AppInput app_input = {0};
  VpxVideoWriter *writer = NULL;
  VpxVideoInfo info = {0};
  vpx_codec_ctx_t codec;
  vpx_codec_enc_cfg_t enc_cfg;
  SvcContext svc_ctx;
  uint32_t i;
  uint32_t frame_cnt = 0;
  vpx_image_t raw;
  vpx_codec_err_t res;
  int pts = 0;            /* PTS starts at 0 */
  int frame_duration = 1; /* 1 timebase tick per frame */
  FILE *infile = NULL;

  memset(&svc_ctx, 0, sizeof(svc_ctx));
  svc_ctx.log_print = 1;
  exec_name = argv[0];
  parse_command_line(argc, argv, &app_input, &svc_ctx, &enc_cfg);

  // Allocate image buffer
  if (!vpx_img_alloc(&raw, VPX_IMG_FMT_I420, enc_cfg.g_w, enc_cfg.g_h, 32))
    die("Failed to allocate image %dx%d\n", enc_cfg.g_w, enc_cfg.g_h);

  if (!(infile = fopen(app_input.input_filename, "rb")))
    die("Failed to open %s for reading\n", app_input.input_filename);

  // Initialize codec
  if (vpx_svc_init(&svc_ctx, &codec, vpx_codec_vp9_cx(), &enc_cfg) !=
      VPX_CODEC_OK)
    die("Failed to initialize encoder\n");

  info.codec_fourcc = VP9_FOURCC;
  info.time_base.numerator = enc_cfg.g_timebase.num;
  info.time_base.denominator = enc_cfg.g_timebase.den;
  if (vpx_svc_get_layer_resolution(&svc_ctx, svc_ctx.spatial_layers - 1,
                                   (unsigned int *)&info.frame_width,
                                   (unsigned int *)&info.frame_height) !=
      VPX_CODEC_OK) {
    die("Failed to get output resolution");
  }
  writer = vpx_video_writer_open(app_input.output_filename, kContainerIVF,
                                 &info);
  if (!writer)
    die("Failed to open %s for writing\n", app_input.output_filename);

  // skip initial frames
  for (i = 0; i < app_input.frames_to_skip; ++i)
    vpx_img_read(&raw, infile);

  // Encode frames
  while (frame_cnt < app_input.frames_to_code) {
    if (!vpx_img_read(&raw, infile))
      break;

    res = vpx_svc_encode(&svc_ctx, &codec, &raw, pts, frame_duration,
                         VPX_DL_REALTIME);
    printf("%s", vpx_svc_get_message(&svc_ctx));
    if (res != VPX_CODEC_OK) {
      die_codec(&codec, "Failed to encode frame");
    }
    if (vpx_svc_get_frame_size(&svc_ctx) > 0) {
      vpx_video_writer_write_frame(writer,
                                   vpx_svc_get_buffer(&svc_ctx),
                                   vpx_svc_get_frame_size(&svc_ctx),
                                   pts);
    }
    ++frame_cnt;
    pts += frame_duration;
  }

  printf("Processed %d frames\n", frame_cnt);

  fclose(infile);
  if (vpx_codec_destroy(&codec)) die_codec(&codec, "Failed to destroy codec");

  vpx_video_writer_close(writer);

  vpx_img_free(&raw);

  // display average size, psnr
  printf("%s", vpx_svc_dump_statistics(&svc_ctx));

  vpx_svc_release(&svc_ctx);

  return EXIT_SUCCESS;
}