add libvpx 89cc6825 (matching current chrome canary) from repo https://chromium.googlesource.com/webm/libvpx

libs/libvpx/examples/vp8cx_set_ref.c

@@ -0,0 +1,194 @@
+/*
+ *  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.
+ */
+
+
+// VP8 Set Reference Frame
+// =======================
+//
+// This is an example demonstrating how to overwrite the VP8 encoder's
+// internal reference frame. In the sample we set the last frame to the
+// current frame. If this is done at a cut scene it will avoid a keyframe.
+// This technique could be used to bounce between two cameras.
+//
+// Note that the decoder would also have to set the reference frame to the
+// same value on the same frame, or the video will become corrupt.
+//
+// Usage
+// -----
+// This example adds a single argument to the `simple_encoder` example,
+// which specifies the frame number to update the reference frame on.
+// The parameter is parsed as follows:
+//
+//
+// Extra Variables
+// ---------------
+// This example maintains the frame number passed on the command line
+// in the `update_frame_num` variable.
+//
+//
+// Configuration
+// -------------
+//
+// The reference frame is updated on the frame specified on the command
+// line.
+//
+// Observing The Effects
+// ---------------------
+// Use the `simple_encoder` example to encode a sample with a cut scene.
+// Determine the frame number of the cut scene by looking for a generated
+// key-frame (indicated by a 'K'). Supply that frame number as an argument
+// to this example, and observe that no key-frame is generated.
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "vpx/vp8cx.h"
+#include "vpx/vpx_encoder.h"
+
+#include "../tools_common.h"
+#include "../video_writer.h"
+
+static const char *exec_name;
+
+void usage_exit(void) {
+  fprintf(stderr, "Usage: %s <width> <height> <infile> <outfile> <frame>\n",
+          exec_name);
+  exit(EXIT_FAILURE);
+}
+
+static int encode_frame(vpx_codec_ctx_t *codec,
+                        vpx_image_t *img,
+                        int frame_index,
+                        VpxVideoWriter *writer) {
+  int got_pkts = 0;
+  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);
+  if (res != VPX_CODEC_OK)
+    die_codec(codec, "Failed to encode frame");
+
+  while ((pkt = vpx_codec_get_cx_data(codec, &iter)) != NULL) {
+    got_pkts = 1;
+
+    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)) {
+        die_codec(codec, "Failed to write compressed frame");
+      }
+
+      printf(keyframe ? "K" : ".");
+      fflush(stdout);
+    }
+  }
+
+  return got_pkts;
+}
+
+int main(int argc, char **argv) {
+  FILE *infile = NULL;
+  vpx_codec_ctx_t codec = {0};
+  vpx_codec_enc_cfg_t cfg = {0};
+  int frame_count = 0;
+  vpx_image_t raw;
+  vpx_codec_err_t res;
+  VpxVideoInfo info = {0};
+  VpxVideoWriter *writer = NULL;
+  const VpxInterface *encoder = NULL;
+  int update_frame_num = 0;
+  const int fps = 30;        // TODO(dkovalev) add command line argument
+  const int bitrate = 200;   // kbit/s TODO(dkovalev) add command line argument
+
+  exec_name = argv[0];
+
+  if (argc != 6)
+    die("Invalid number of arguments");
+
+  // TODO(dkovalev): add vp9 support and rename the file accordingly
+  encoder = get_vpx_encoder_by_name("vp8");
+  if (!encoder)
+    die("Unsupported codec.");
+
+  update_frame_num = atoi(argv[5]);
+  if (!update_frame_num)
+    die("Couldn't parse frame number '%s'\n", argv[5]);
+
+  info.codec_fourcc = encoder->fourcc;
+  info.frame_width = strtol(argv[1], NULL, 0);
+  info.frame_height = strtol(argv[2], 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.");
+  }
+
+  printf("Using %s\n", vpx_codec_iface_name(encoder->codec_interface()));
+
+  res = vpx_codec_enc_config_default(encoder->codec_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;
+
+  writer = vpx_video_writer_open(argv[4], kContainerIVF, &info);
+  if (!writer)
+    die("Failed to open %s for writing.", argv[4]);
+
+  if (!(infile = fopen(argv[3], "rb")))
+    die("Failed to open %s for reading.", argv[3]);
+
+  if (vpx_codec_enc_init(&codec, encoder->codec_interface(), &cfg, 0))
+    die_codec(&codec, "Failed to initialize encoder");
+
+  // Encode frames.
+  while (vpx_img_read(&raw, infile)) {
+    if (frame_count + 1 == update_frame_num) {
+      vpx_ref_frame_t ref;
+      ref.frame_type = VP8_LAST_FRAME;
+      ref.img = raw;
+      if (vpx_codec_control(&codec, VP8_SET_REFERENCE, &ref))
+        die_codec(&codec, "Failed to set reference frame");
+    }
+
+    encode_frame(&codec, &raw, frame_count++, writer);
+  }
+
+  // Flush encoder.
+  while (encode_frame(&codec, NULL, -1, writer)) {}
+
+  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;
+}