Add example project for h264 and opus streaming

examples/streamer/h264fileparser.cpp

@@ -0,0 +1,70 @@
+/*
+ * 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 "h264fileparser.hpp"
+#include <fstream>
+#include "rtc/rtc.hpp"
+
+using namespace std;
+
+H264FileParser::H264FileParser(string directory, uint32_t fps, bool loop): FileParser(directory, ".h264", fps, loop) { }
+
+void H264FileParser::loadNextSample() {
+    FileParser::loadNextSample();
+
+    unsigned long long i = 0;
+    while (i < sample.size()) {
+        assert(i + 4 < sample.size());
+        auto lengthPtr = (uint32_t *) (sample.data() + i);
+        uint32_t length = ntohl(*lengthPtr);
+        auto naluStartIndex = i + 4;
+        auto naluEndIndex = naluStartIndex + length;
+        assert(naluEndIndex <= sample.size());
+        auto header = reinterpret_cast<rtc::NalUnitHeader *>(sample.data() + naluStartIndex);
+        auto type = header->unitType();
+        switch (type) {
+            case 7:
+                previousUnitType7 = {sample.begin() + i, sample.begin() + naluEndIndex};
+                break;
+            case 8:
+                previousUnitType8 = {sample.begin() + i, sample.begin() + naluEndIndex};;
+                break;
+            case 5:
+                previousUnitType5 = {sample.begin() + i, sample.begin() + naluEndIndex};;
+                break;
+        }
+        i = naluEndIndex;
+    }
+}
+
+vector<byte> H264FileParser::initialNALUS() {
+    vector<byte> units{};
+    if (previousUnitType7.has_value()) {
+        auto nalu = previousUnitType7.value();
+        units.insert(units.end(), nalu.begin(), nalu.end());
+    }
+    if (previousUnitType8.has_value()) {
+        auto nalu = previousUnitType8.value();
+        units.insert(units.end(), nalu.begin(), nalu.end());
+    }
+    if (previousUnitType5.has_value()) {
+        auto nalu = previousUnitType5.value();
+        units.insert(units.end(), nalu.begin(), nalu.end());
+    }
+    return units;
+}