libvpx: Pull from upstream

source/libvpx/examples/simple_encoder.c

 /*
  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 46 matching lines @@
 // Encoding A Frame
 // ----------------
 // The frame is read as a continuous block (size width * height * 3 / 2)
 // from the input file. If a frame was read (the input file has not hit
 // EOF) then the frame is passed to the encoder. Otherwise, a NULL
 // is passed, indicating the End-Of-Stream condition to the encoder. The
 // `frame_cnt` is reused as the presentation time stamp (PTS) and each
 // frame is shown for one frame-time in duration. The flags parameter is
 // unused in this example. The deadline is set to VPX_DL_REALTIME to
 // make the example run as quickly as possible.
+
+// Forced Keyframes
+// ----------------
+// Keyframes can be forced by setting the VPX_EFLAG_FORCE_KF bit of the
+// flags passed to `vpx_codec_control()`. In this example, we force a
+// keyframe every <keyframe-interval> frames. Note, the output stream can
+// contain additional keyframes beyond those that have been forced using the
+// VPX_EFLAG_FORCE_KF flag because of automatic keyframe placement by the
+// encoder.
 //
 // Processing The Encoded Data
 // ---------------------------
 // Each packet of type `VPX_CODEC_CX_FRAME_PKT` contains the encoded data
 // for this frame. We write a IVF frame header, followed by the raw data.
 //
 // Cleanup
 // -------
 // The `vpx_codec_destroy` call frees any memory allocated by the codec.
 //
@@ skipping 19 matching lines @@
 #include "vpx/vpx_encoder.h"
 
 #include "./tools_common.h"
 #include "./video_writer.h"
 
 static const char *exec_name;
 
 void usage_exit() {
   fprintf(stderr,
           "Usage: %s <codec> <width> <height> <infile> <outfile> "
-              "[<error-resilient>]\nSee comments in simple_encoder.c for more "
-              "information.\n",
+              "<keyframe-interval> [<error-resilient>]\nSee comments in "
+              "simple_encoder.c for more information.\n",
           exec_name);
   exit(EXIT_FAILURE);
 }
 
 static void encode_frame(vpx_codec_ctx_t *codec,
                          vpx_image_t *img,
                          int frame_index,
+                         int flags,
                          VpxVideoWriter *writer) {
   vpx_codec_iter_t iter = NULL;
   const vpx_codec_cx_pkt_t *pkt = NULL;
-  const vpx_codec_err_t res = vpx_codec_encode(codec, img, frame_index, 1, 0,
-                                               VPX_DL_GOOD_QUALITY);
+  const vpx_codec_err_t res = vpx_codec_encode(codec, img, frame_index, 1,
+                                               flags, VPX_DL_GOOD_QUALITY);
   if (res != VPX_CODEC_OK)
     die_codec(codec, "Failed to encode frame");
 
   while ((pkt = vpx_codec_get_cx_data(codec, &iter)) != NULL) {
     if (pkt->kind == VPX_CODEC_CX_FRAME_PKT) {
       const int keyframe = (pkt->data.frame.flags & VPX_FRAME_IS_KEY) != 0;
       if (!vpx_video_writer_write_frame(writer,
                                         pkt->data.frame.buf,
                                         pkt->data.frame.sz,
                                         pkt->data.frame.pts)) {
@@ skipping 11 matching lines @@
   vpx_codec_ctx_t codec;
   vpx_codec_enc_cfg_t cfg;
   int frame_count = 0;
   vpx_image_t raw;
   vpx_codec_err_t res;
   VpxVideoInfo info = {0};
   VpxVideoWriter *writer = NULL;
   const VpxInterface *encoder = NULL;
   const int fps = 30;        // TODO(dkovalev) add command line argument
   const int bitrate = 200;   // kbit/s TODO(dkovalev) add command line argument
+  int keyframe_interval = 0;
+
+  // TODO(dkovalev): Add some simple command line parsing code to make the
+  // command line more flexible.
   const char *codec_arg = NULL;
   const char *width_arg = NULL;
   const char *height_arg = NULL;
   const char *infile_arg = NULL;
   const char *outfile_arg = NULL;
+  const char *keyframe_interval_arg = NULL;
 
   exec_name = argv[0];
 
-  if (argc < 6)
+  if (argc < 7)
     die("Invalid number of arguments");
 
   codec_arg = argv[1];
   width_arg = argv[2];
   height_arg = argv[3];
   infile_arg = argv[4];
   outfile_arg = argv[5];
+  keyframe_interval_arg = argv[6];
 
   encoder = get_vpx_encoder_by_name(codec_arg);
   if (!encoder)
      die("Unsupported codec.");
 
   info.codec_fourcc = encoder->fourcc;
   info.frame_width = strtol(width_arg, NULL, 0);
   info.frame_height = strtol(height_arg, NULL, 0);
   info.time_base.numerator = 1;
   info.time_base.denominator = fps;
 
   if (info.frame_width <= 0 ||
       info.frame_height <= 0 ||
       (info.frame_width % 2) != 0 ||
       (info.frame_height % 2) != 0) {
     die("Invalid frame size: %dx%d", info.frame_width, info.frame_height);
   }
 
   if (!vpx_img_alloc(&raw, VPX_IMG_FMT_I420, info.frame_width,
                                              info.frame_height, 1)) {
     die("Failed to allocate image.");
   }
 
+  keyframe_interval = strtol(keyframe_interval_arg, NULL, 0);
+  if (keyframe_interval < 0)
+    die("Invalid keyframe interval value.");
+
   printf("Using %s\n", vpx_codec_iface_name(encoder->interface()));
 
   res = vpx_codec_enc_config_default(encoder->interface(), &cfg, 0);
   if (res)
     die_codec(&codec, "Failed to get default codec config.");
 
   cfg.g_w = info.frame_width;
   cfg.g_h = info.frame_height;
   cfg.g_timebase.num = info.time_base.numerator;
   cfg.g_timebase.den = info.time_base.denominator;
   cfg.rc_target_bitrate = bitrate;
-  cfg.g_error_resilient = argc > 6 ? strtol(argv[6], NULL, 0) : 0;
+  cfg.g_error_resilient = argc > 7 ? strtol(argv[7], NULL, 0) : 0;
 
   writer = vpx_video_writer_open(outfile_arg, kContainerIVF, &info);
   if (!writer)
     die("Failed to open %s for writing.", outfile_arg);
 
   if (!(infile = fopen(infile_arg, "rb")))
     die("Failed to open %s for reading.", infile_arg);
 
   if (vpx_codec_enc_init(&codec, encoder->interface(), &cfg, 0))
     die_codec(&codec, "Failed to initialize encoder");
 
-  while (vpx_img_read(&raw, infile))
-    encode_frame(&codec, &raw, frame_count++, writer);
-  encode_frame(&codec, NULL, -1, writer);  // flush the encoder
+  while (vpx_img_read(&raw, infile)) {
+    int flags = 0;
+    if (keyframe_interval > 0 && frame_count % keyframe_interval == 0)
+      flags |= VPX_EFLAG_FORCE_KF;
+    encode_frame(&codec, &raw, frame_count++, flags, writer);
+  }
+  encode_frame(&codec, NULL, -1, 0, writer);  // flush the encoder
 
   printf("\n");
   fclose(infile);
   printf("Processed %d frames.\n", frame_count);
 
   vpx_img_free(&raw);
   if (vpx_codec_destroy(&codec))
     die_codec(&codec, "Failed to destroy codec.");
 
   vpx_video_writer_close(writer);
 
   return EXIT_SUCCESS;
 }