1 files changed, 154 insertions, 0 deletions
diff --git a/chromium/third_party/libvpx/source/libvpx/examples/decode_with_drops.c b/chromium/third_party/libvpx/source/libvpx/examples/decode_with_drops.c
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index 00000000000..af1aa636b4e
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+++ b/chromium/third_party/libvpx/source/libvpx/examples/decode_with_drops.c
@@ -0,0 +1,154 @@
+/*
+ *  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.
+ */
+
+// Decode With Drops Example
+// =========================
+//
+// This is an example utility which drops a series of frames, as specified
+// on the command line. This is useful for observing the error recovery
+// features of the codec.
+//
+// Usage
+// -----
+// This example adds a single argument to the `simple_decoder` example,
+// which specifies the range or pattern of frames to drop. The parameter is
+// parsed as follows:
+//
+// Dropping A Range Of Frames
+// --------------------------
+// To drop a range of frames, specify the starting frame and the ending
+// frame to drop, separated by a dash. The following command will drop
+// frames 5 through 10 (base 1).
+//
+//  $ ./decode_with_drops in.ivf out.i420 5-10
+//
+//
+// Dropping A Pattern Of Frames
+// ----------------------------
+// To drop a pattern of frames, specify the number of frames to drop and
+// the number of frames after which to repeat the pattern, separated by
+// a forward-slash. The following command will drop 3 of 7 frames.
+// Specifically, it will decode 4 frames, then drop 3 frames, and then
+// repeat.
+//
+//  $ ./decode_with_drops in.ivf out.i420 3/7
+//
+//
+// Extra Variables
+// ---------------
+// This example maintains the pattern passed on the command line in the
+// `n`, `m`, and `is_range` variables:
+//
+//
+// Making The Drop Decision
+// ------------------------
+// The example decides whether to drop the frame based on the current
+// frame number, immediately before decoding the frame.
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define VPX_CODEC_DISABLE_COMPAT 1
+
+#include "vpx/vp8dx.h"
+#include "vpx/vpx_decoder.h"
+
+#include "./tools_common.h"
+#include "./video_reader.h"
+#include "./vpx_config.h"
+
+static const char *exec_name;
+
+void usage_exit() {
+  fprintf(stderr, "Usage: %s <infile> <outfile> <N-M|N/M>\n", exec_name);
+  exit(EXIT_FAILURE);
+}
+
+int main(int argc, char **argv) {
+  int frame_cnt = 0;
+  FILE *outfile = NULL;
+  vpx_codec_ctx_t codec;
+  const VpxInterface *decoder = NULL;
+  VpxVideoReader *reader = NULL;
+  const VpxVideoInfo *info = NULL;
+  int n = 0;
+  int m = 0;
+  int is_range = 0;
+  char *nptr = NULL;
+
+  exec_name = argv[0];
+
+  if (argc != 4)
+    die("Invalid number of arguments.");
+
+  reader = vpx_video_reader_open(argv[1]);
+  if (!reader)
+    die("Failed to open %s for reading.", argv[1]);
+
+  if (!(outfile = fopen(argv[2], "wb")))
+    die("Failed to open %s for writing.", argv[2]);
+
+  n = strtol(argv[3], &nptr, 0);
+  m = strtol(nptr + 1, NULL, 0);
+  is_range = (*nptr == '-');
+  if (!n || !m || (*nptr != '-' && *nptr != '/'))
+    die("Couldn't parse pattern %s.\n", argv[3]);
+
+  info = vpx_video_reader_get_info(reader);
+
+  decoder = get_vpx_decoder_by_fourcc(info->codec_fourcc);
+  if (!decoder)
+    die("Unknown input codec.");
+
+  printf("Using %s\n", vpx_codec_iface_name(decoder->interface()));
+
+  if (vpx_codec_dec_init(&codec, decoder->interface(), NULL, 0))
+    die_codec(&codec, "Failed to initialize decoder.");
+
+  while (vpx_video_reader_read_frame(reader)) {
+    vpx_codec_iter_t iter = NULL;
+    vpx_image_t *img = NULL;
+    size_t frame_size = 0;
+    int skip;
+    const unsigned char *frame = vpx_video_reader_get_frame(reader,
+                                                            &frame_size);
+    if (vpx_codec_decode(&codec, frame, (unsigned int)frame_size, NULL, 0))
+      die_codec(&codec, "Failed to decode frame.");
+
+    ++frame_cnt;
+
+    skip = (is_range && frame_cnt >= n && frame_cnt <= m) ||
+           (!is_range && m - (frame_cnt - 1) % m <= n);
+
+    if (!skip) {
+      putc('.', stdout);
+
+      while ((img = vpx_codec_get_frame(&codec, &iter)) != NULL)
+        vpx_img_write(img, outfile);
+    } else {
+      putc('X', stdout);
+    }
+
+    fflush(stdout);
+  }
+
+  printf("Processed %d frames.\n", frame_cnt);
+  if (vpx_codec_destroy(&codec))
+    die_codec(&codec, "Failed to destroy codec.");
+
+  printf("Play: ffplay -f rawvideo -pix_fmt yuv420p -s %dx%d %s\n",
+         info->frame_width, info->frame_height, argv[2]);
+
+  vpx_video_reader_close(reader);
+  fclose(outfile);
+
+  return EXIT_SUCCESS;
+}