Add example project for h264 and opus streaming

examples/streamer/fileparser.cpp

@@ -0,0 +1,59 @@
+/*
+ * libdatachannel streamer example
+ * Copyright (c) 2020 Filip Klembara (in2core)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "fileparser.hpp"
+#include <fstream>
+
+using namespace std;
+
+FileParser::FileParser(string directory, string extension, uint32_t samplesPerSecond, bool loop): sampleDuration_us(1000 * 1000 / samplesPerSecond), StreamSource() {
+    this->directory = directory;
+    this->extension = extension;
+    this->loop = loop;
+}
+
+void FileParser::start() {
+    sampleTime_us = -sampleDuration_us;
+    loadNextSample();
+}
+
+void FileParser::stop() {
+    StreamSource::stop();
+    counter = -1;
+}
+
+void FileParser::loadNextSample() {
+    string frame_id = to_string(++counter);
+
+    string url = directory + "/sample-" + frame_id + extension;
+    ifstream source(url, ios_base::binary);
+    if (!source) {
+        if (loop && counter > 0) {
+            loopTimestampOffset = sampleTime_us;
+            counter = -1;
+            loadNextSample();
+            return;
+        }
+        sample = {};
+        return;
+    }
+
+    vector<uint8_t> fileContents((std::istreambuf_iterator<char>(source)), std::istreambuf_iterator<char>());
+    sample = *reinterpret_cast<vector<byte> *>(&fileContents);
+    sampleTime_us += sampleDuration_us;
+}