Scan for audio properties, metadata, and embedded images in one single pass. Removed now useless lmsmetadata library + reworked code accordingly

src/libs/audio/impl/ffmpeg/Transcoder.hpp

@@ -0,0 +1,55 @@
+/*
+ * Copyright (C) 2015 Emeric Poupon
+ *
+ * This file is part of LMS.
+ *
+ * LMS 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * LMS 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 LMS.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include "audio/ITranscoder.hpp"
+
+namespace lms::core
+{
+    class IChildProcess;
+}
+
+namespace lms::audio::ffmpeg
+{
+    class Transcoder : public ITranscoder
+    {
+    public:
+        Transcoder(const TranscodeParameters& parameters);
+        ~Transcoder() override;
+        Transcoder(const Transcoder&) = delete;
+        Transcoder& operator=(const Transcoder&) = delete;
+
+    private:
+        void asyncRead(std::byte* buffer, std::size_t bufferSize, ReadCallback) override;
+        std::size_t readSome(std::byte* buffer, std::size_t bufferSize) override;
+
+        std::string_view getOutputMimeType() const override;
+        const TranscodeOutputParameters& getOutputParameters() const override { return _outputParams; }
+
+        bool finished() const override;
+        static void init();
+        void start();
+
+        const std::size_t _debugId{};
+        const TranscodeInputParameters _inputParams;
+        const TranscodeOutputParameters _outputParams;
+        std::unique_ptr<core::IChildProcess> _childProcess;
+    };
+} // namespace lms::audio::ffmpeg