Decode h264 fmtp sprop-parameter-sets to binary.

webrtc/modules/video_coding/h264_sprop_parameter_sets.cc

Index: webrtc/modules/video_coding/h264_sprop_parameter_sets.cc
diff --git a/webrtc/modules/video_coding/h264_sprop_parameter_sets.cc b/webrtc/modules/video_coding/h264_sprop_parameter_sets.cc
new file mode 100644
index 0000000000000000000000000000000000000000..d50c783534618d1eae8b579fba043197719f21ed
--- /dev/null
+++ b/webrtc/modules/video_coding/h264_sprop_parameter_sets.cc
@@ -0,0 +1,58 @@
+/*
+ *  Copyright (c) 2016 The WebRTC 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.
+ */
+
+#include "webrtc/modules/video_coding/h264_sprop_parameter_sets.h"
+
+#include "webrtc/base/base64.h"
+#include "webrtc/base/bitbuffer.h"
+#include "webrtc/base/bytebuffer.h"
+#include "webrtc/base/logging.h"
+
+namespace webrtc {
+
+static bool DecodeAndConvert(const std::string& base64,
+                             std::vector<uint8_t>* binary) {

[sprang_webrtc, 2016/12/06 18:23:18]

Why static?

We usually just put these kind of helper methods and constants inside an
anonymous namespace.

[johan, 2016/12/07 17:10:40]

Well, old habit from plain c days. *In this place* the "static" keyword
accomplishes nearly the same thing as an anonymous namespace. Changing this to
anonymous namespace.

+  static constexpr rtc::Base64::DecodeFlags flags = rtc::Base64::DO_STRICT;
+  // TODO(johan): Directly decode to std::vector<uint8_t> when available.
+  std::vector<char> tmp;
+  bool success = rtc::Base64::DecodeFromArray(base64.data(), base64.size(),
+                                              flags, &tmp, nullptr);
+  if (!success) {

[sprang_webrtc, 2016/12/06 18:23:18]

Don't need this temporary, just if (!DecodeFromArray(...)) return false;

[johan, 2016/12/07 17:10:40]

Done.

[sprang_webrtc, 2016/12/08 10:08:37]

Seems to still be there?

+    return false;
+  }
+  const uint8_t* data = reinterpret_cast<uint8_t*>(tmp.data());
+  binary->assign(data, data + tmp.size());
+  return success;
+}
+
+bool H264SpropParameterSets::DecodeSprop(const std::string& sprop) {
+  size_t separator_pos = sprop.find(',');
+  if ((separator_pos <= 0) || (separator_pos >= sprop.length() - 1)) {
+    LOG(LS_WARNING) << "Invalid seperator position " << separator_pos << " *"
+                    << sprop << "*";
+    return false;
+  }
+  std::string sps_str = sprop.substr(0, separator_pos);
+  std::string pps_str = sprop.substr(separator_pos + 1, std::string::npos);
+  bool success;

[sprang_webrtc, 2016/12/06 18:23:18]

dito

[johan, 2016/12/07 17:10:40]

Done.

+  success = DecodeAndConvert(sps_str, &sps_);
+  if (!success) {
+    LOG(LS_WARNING) << "Failed to decode sps *" << sprop << "*";

[sprang_webrtc, 2016/12/06 18:23:18]

Should that be sps_str?

[johan, 2016/12/07 17:10:40]

Actually I want to output the entire string in case of an parsing error.
Clarified the log message.

+    return false;
+  }
+  success = DecodeAndConvert(pps_str, &pps_);
+  if (!success) {
+    LOG(LS_WARNING) << "Failed to decode pps *" << sprop << "*";
+    return false;
+  }
+  return true;
+}
+
+}  // namespace webrtc