Made the player work, first WIP version

approot/templates.xml

@@ -4,7 +4,7 @@
 <message id="Lms.template">
 	${navbar-top class="main-nav"}
 	${contents class="container"}
-	${player}
+	${player class="Lms-player"}
 </message>
 
 </messages>

docroot/css/lms.css

@@ -3,3 +3,7 @@
 	font-weight: bold;
 }
 
+.Lms-player {
+	background-color: grey;
+}
+

src/Makefile.am

@@ -39,7 +39,6 @@ lms_SOURCES = \
 	$(srcdir)/ui/explore/ReleasesView.cpp			\
 	$(srcdir)/ui/explore/ReleaseView.cpp			\
 	$(srcdir)/ui/explore/TracksView.cpp			\
-	$(srcdir)/ui/resource/AvConvTranscodeStreamResource.cpp	\
 	$(srcdir)/ui/resource/ImageResource.cpp			\
 	$(srcdir)/ui/resource/TranscodeResource.cpp		\
 	$(srcdir)/utils/Config.cpp				\

src/av/AvInfo.cpp

@@ -201,7 +201,7 @@ MediaFile::getStreams(Stream::Type type) const
 	return res;
 }
 
-int
+boost::optional<std::size_t>
 MediaFile::getBestStreamId(Stream::Type type) const
 {
 	if (_context == nullptr)
@@ -215,7 +215,7 @@ MediaFile::getBestStreamId(Stream::Type type) const
 		case Stream::Type::Video: avMediaType = AVMEDIA_TYPE_VIDEO; break;
 		case Stream::Type::Subtitle: avMediaType = AVMEDIA_TYPE_SUBTITLE; break;
 		default:
-			return -1;
+			return boost::none;
 	}
 
 	int res = av_find_best_stream(_context,
@@ -227,7 +227,7 @@ MediaFile::getBestStreamId(Stream::Type type) const
 	if (res < 0)
 	{
 		LMS_LOG(AV, ERROR) << "Cannot find best stream for type " << streamType_to_string(type);
-		return -1;
+		return boost::none;
 	}
 
 	return res;

src/av/AvInfo.hpp

@@ -35,6 +35,7 @@ extern "C"
 #include <cstdint>
 #include <map>
 
+#include <boost/optional.hpp>
 #include <boost/filesystem/path.hpp>
 #include <boost/date_time/posix_time/posix_time_types.hpp> //no i/o just types
 
@@ -84,7 +85,7 @@ class MediaFile
 		std::map<std::string, std::string>	getMetaData(void);
 
 		std::vector<Stream>	getStreams(Stream::Type type) const;
-		int			getBestStreamId(Stream::Type type) const; // -1 if failure/unknown
+		boost::optional<std::size_t>	getBestStreamId(Stream::Type type) const; // none if failure/unknown
 		bool			hasAttachedPictures(void) const;
 		std::vector<Picture>	getAttachedPictures(std::size_t nbMaxPictures) const;
 

src/av/AvTranscoder.cpp

@@ -39,11 +39,8 @@ static std::vector<EncodingInfo> encodingInfos =
 {
 	{Encoding::MP3,	"audio/mp3", 0},
 	{Encoding::OGA, "audio/ogg", 1},
-	{Encoding::OGV, "video/ogg", 2},
 	{Encoding::WEBMA, "audio/webm", 3},
-	{Encoding::WEBMV, "video/webm", 4},
 	{Encoding::M4A, "audio/mp4", 5},
-	{Encoding::M4V, "video/mp4", 6},
 };
 
 std::string encoding_to_mimetype(Encoding encoding)
@@ -139,10 +136,10 @@ Transcoder::start()
 	args.push_back("-nostdin");
 
 	// input Offset
-	if (_parameters.getOffset().total_seconds() > 0)
+	if (_parameters.offset.total_seconds() > 0)
 	{
 		args.push_back("-ss");
-		args.push_back(std::to_string(_parameters.getOffset().total_seconds()));
+		args.push_back(std::to_string(_parameters.offset.total_seconds()));
 	}
 
 	// Input file
@@ -151,20 +148,24 @@ Transcoder::start()
 
 	// Output bitrates
 	args.push_back("-b:a");
-	args.push_back(std::to_string(_parameters.getBitrate(Stream::Type::Audio)));
+	args.push_back(std::to_string(_parameters.bitrate));
-//	if (_parameters.getOutputFormat().getType() == Format::Video)
-//		oss << " -b:v " << _parameters.getOutputBitrate(Stream::Video);
 
-	// Stream mapping
+	// Stream mapping, if set
-	for (int streamId : _parameters.getSelectedStreamIds())
+	if (_parameters.stream)
 	{
-		// 0 means the first input file
 		args.push_back("-map");
-		args.push_back("0:" + std::to_string(streamId));
+		args.push_back("0:" + std::to_string(*_parameters.stream));
 	}
 
+	// Strip metadata
+	args.push_back("-map_metadata");
+	args.push_back("-1");
+
+	// Skip video flows (including covers)
+	args.push_back("-vn");
+
 	// Codecs and formats
-	switch( _parameters.getEncoding())
+	switch( _parameters.encoding)
 	{
 		case Encoding::MP3:
 			args.push_back("-f");
@@ -178,20 +179,6 @@ Transcoder::start()
 			args.push_back("ogg");
 			break;
 
-		case Encoding::OGV:
-			args.push_back("-acodec");
-			args.push_back("libvorbis");
-			args.push_back("-ac");
-			args.push_back("2");
-			args.push_back("-ar");
-			args.push_back("44100");
-			args.push_back("-vcodec");
-			args.push_back("libtheora");
-			args.push_back("-threads");
-			args.push_back("4");
-			args.push_back("-f");
-			args.push_back("ogg");
-			break;
 		case Encoding::WEBMA:
 			args.push_back("-codec:a");
 			args.push_back("libvorbis");
@@ -199,21 +186,6 @@ Transcoder::start()
 			args.push_back("webm");
 			break;
 
-		case Encoding::WEBMV:
-			args.push_back("-acodec");
-			args.push_back("libvorbis");
-			args.push_back("-ac");
-			args.push_back("2");
-			args.push_back("-ar");
-			args.push_back("44100");
-			args.push_back("-vcodec");
-			args.push_back("libvpx");
-			args.push_back("-threads");
-			args.push_back("4");
-			args.push_back("-f");
-			args.push_back("webm");
-			break;
-
 		case Encoding::M4A:
 			args.push_back("-acodec");
 			args.push_back("aac");
@@ -223,21 +195,6 @@ Transcoder::start()
 			args.push_back("experimental");
 			break;
 
-		case Encoding::M4V:
-			args.push_back("-acodec");
-			args.push_back("aac");
-			args.push_back("-strict");
-			args.push_back("experimental");
-			args.push_back("-ac");
-			args.push_back("2");
-			args.push_back("-ar");
-			args.push_back("-44100");
-			args.push_back("-vcodec");
-			args.push_back("libx264");
-			args.push_back("-f");
-			args.push_back("m4v");
-			break;
-
 		default:
 			return false;
 	}

src/av/AvTranscoder.hpp

@@ -25,8 +25,8 @@
 #include <pstreams/pstream.h>
 
 #include <boost/date_time/posix_time/posix_time_types.hpp> //no i/o just types
-#include <boost/filesystem/path.hpp>
 #include <boost/filesystem.hpp>
+#include <boost/optional.hpp>
 
 #include "AvInfo.hpp"
 
@@ -39,42 +39,23 @@ enum class Encoding
 	OGV,
 	MP3,
 	WEBMA,
-	WEBMV,
 	M4A,
-	M4V,
 };
 
 std::string encoding_to_mimetype(Encoding encoding);
 int encoding_to_int(Encoding encoding);
 Encoding encoding_from_int(int encoding);
 
-class TranscodeParameters
+struct TranscodeParameters
 {
-	public:
+	Encoding	encoding = Encoding::MP3;
+	boost::optional<std::size_t> stream = boost::none; // Id of the stream to be transcoded (auto detect by default)
+	std::size_t	bitrate = 128000;
+	boost::posix_time::time_duration offset = boost::posix_time::seconds(0);
 
-		// Setters
+	TranscodeParameters() {}
-		void setEncoding(Encoding encoding)			{ _encoding = encoding; }
-		void setOffset(boost::posix_time::time_duration offset)	{_offset = offset; }
-		void setBitrate(Stream::Type type, std::size_t bitrate)	{ _outputBitrate[type] = bitrate; }
-
-		// Manually add the streams to be transcoded
-		// If no stream is added, input streams are selected automatically
-		void addStream(int inputStreamId)	{ _selectedStreams.insert(inputStreamId); }
-
-		// Getters
-		Encoding				getEncoding(void) const { return _encoding; }
-		boost::posix_time::time_duration	getOffset(void) const { return _offset; }
-		std::set<int>				getSelectedStreamIds(void) const { return _selectedStreams; }
-		std::size_t				getBitrate(Stream::Type type) { return _outputBitrate[type]; }
-
-	private:
-		Encoding				_encoding = Encoding::MP3;
-		boost::posix_time::time_duration	_offset = boost::posix_time::seconds(0);
-		std::set<int>				_selectedStreams;
-		std::map<Stream::Type, std::size_t>	_outputBitrate = { {Stream::Type::Audio, 0}, { Stream::Type::Video, 0}, { Stream::Type::Subtitle, 0} };
 };
 
-
 class Transcoder
 {
 	public:
@@ -89,7 +70,7 @@ class Transcoder
 
 		bool start();
 		void process(std::vector<unsigned char>& output, std::size_t maxSize);
-		bool isComplete(void)	{ return _isComplete; }
+		bool isComplete(void) const { return _isComplete; }
 
 		const TranscodeParameters& getParameters() const { return _parameters; }
 

src/ui/LmsApplication.cpp

@@ -40,6 +40,9 @@
 #include "admin/DatabaseSettingsView.hpp"
 #include "admin/AdminWizardView.hpp"
 
+#include "resource/ImageResource.hpp"
+#include "resource/TranscodeResource.hpp"
+
 #include "LmsApplication.hpp"
 
 namespace UserInterface {
@@ -356,6 +359,7 @@ LmsApplication::handleAuthEvent(void)
 
 	// Events from the PlayQueue
 	playqueue->playTrack.connect(player, &MediaPlayer::playTrack);
+	playqueue->playbackStop.connect(player, &MediaPlayer::stop);
 
 	// Events from MediaScanner
 	if (CurrentUser()->isAdmin())

src/ui/LmsApplication.hpp

@@ -26,12 +26,13 @@
 #include "database/DatabaseHandler.hpp"
 #include "scanner/MediaScanner.hpp"
 
-#include "resource/ImageResource.hpp"
-#include "resource/TranscodeResource.hpp"
 #include "Auth.hpp"
 
 namespace UserInterface {
 
+class TranscodeResource;
+class ImageResource;
+
 class LmsApplication : public Wt::WApplication
 {
 	public:

src/ui/MediaPlayer.cpp

@@ -21,15 +21,29 @@
 #include <Wt/WTemplate>
 #include <Wt/WText>
 
+#include "av/AvInfo.hpp"
 #include "utils/Logger.hpp"
 
+#include "resource/TranscodeResource.hpp"
+
+#include "LmsApplication.hpp"
 #include "MediaPlayer.hpp"
 
+
 namespace UserInterface {
 
 MediaPlayer::MediaPlayer(Wt::WContainerWidget* parent)
 : Wt::WContainerWidget(parent)
 {
+	_audio = new Wt::WAudio(this);
+	_audio->setOptions(Wt::WAudio::Autoplay);
+	_audio->setPreloadMode(Wt::WAudio::PreloadNone);
+
+	_audio->ended().connect(std::bind([=] ()
+	{
+		playbackEnded.emit();
+	}));
+
 	auto player = new Wt::WTemplate(Wt::WString::tr("template-mediaplayer"), this);
 
 	auto playPauseBtn = new Wt::WText(Wt::WString::tr("btn-mediaplayer-play"), Wt::XHTMLText);
@@ -66,9 +80,36 @@ MediaPlayer::MediaPlayer(Wt::WContainerWidget* parent)
 }
 
 void
-MediaPlayer::playTrack(Database::Track::id_type id)
+MediaPlayer::playTrack(Database::Track::id_type trackId)
 {
-	LMS_LOG(UI, DEBUG) << "Playing track ID = " << id;
+	LMS_LOG(UI, DEBUG) << "Playing track ID = " << trackId;
+
+	Wt::Dbo::Transaction transaction(DboSession());
+	auto track = Database::Track::getById(DboSession(), trackId);
+	transaction.commit();
+
+	// Analyse track, select the best media stream
+	Av::MediaFile mediaFile(track->getPath());
+
+	if (!mediaFile.open() || !mediaFile.scan())
+	{
+		LMS_LOG(UI, ERROR) << "Cannot open file '" << track->getPath();
+		return;
+	}
+
+	auto streamId = mediaFile.getBestStreamId(Av::Stream::Type::Audio);
+
+	_audio->pause();
+	_audio->clearSources();
+	_audio->addSource(LmsApp->getTranscodeResource()->getUrl(trackId, Av::Encoding::MP3, boost::posix_time::seconds(0), streamId));
+	_audio->setPreloadMode(Wt::WAudio::PreloadNone);
+	_audio->play();
+}
+
+void
+MediaPlayer::stop()
+{
+	_audio->pause();
 }
 
 } // namespace UserInterface

src/ui/MediaPlayer.hpp

@@ -20,6 +20,7 @@
 #pragma once
 
 #include <Wt/WSignal>
+#include <Wt/WAudio>
 #include <Wt/WContainerWidget>
 
 #include "database/Types.hpp"
@@ -31,6 +32,7 @@ class MediaPlayer : public Wt::WContainerWidget
 	public:
 		MediaPlayer(Wt::WContainerWidget* parent = 0);
 
+		void stop();
 		void playTrack(Database::Track::id_type);
 
 		// Signals
@@ -38,6 +40,8 @@ class MediaPlayer : public Wt::WContainerWidget
 		Wt::Signal<void>	playPrevious;
 		Wt::Signal<void>	playNext;
 
+	private:
+		Wt::WAudio* _audio;
 };
 
 } // namespace UserInterface

src/ui/PlayQueueView.cpp

@@ -93,6 +93,7 @@ PlayQueue::stop()
 {
 	updateCurrentTrack(false);
 	_trackPos.reset();
+	playbackStop.emit();
 }
 
 void

src/ui/PlayQueueView.hpp

@@ -47,6 +47,9 @@ class PlayQueue : public Wt::WContainerWidget
 		// Signal emitted when a track is to be played
 		Wt::Signal<Database::Track::id_type> playTrack;
 
+		// Signal emitted when play has to be stopped
+		Wt::Signal<void> playbackStop;
+
 	private:
 		void addSome();
 		void updateInfo();

src/ui/explore/ArtistView.cpp

@@ -28,6 +28,8 @@
 #include "utils/Logger.hpp"
 #include "utils/Utils.hpp"
 
+#include "resource/ImageResource.hpp"
+
 #include "LmsApplication.hpp"
 #include "Filters.hpp"
 #include "ArtistView.hpp"

src/ui/explore/ReleaseView.cpp

@@ -28,6 +28,8 @@
 #include "utils/Logger.hpp"
 #include "utils/Utils.hpp"
 
+#include "resource/ImageResource.hpp"
+
 #include "LmsApplication.hpp"
 #include "Filters.hpp"
 #include "ReleaseView.hpp"

src/ui/explore/ReleasesView.cpp

@@ -28,6 +28,8 @@
 #include "utils/Logger.hpp"
 #include "utils/Utils.hpp"
 
+#include "resource/ImageResource.hpp"
+
 #include "LmsApplication.hpp"
 #include "Filters.hpp"
 #include "ReleasesView.hpp"

src/ui/explore/TracksView.cpp

@@ -27,6 +27,8 @@
 #include "utils/Logger.hpp"
 #include "utils/Utils.hpp"
 
+#include "resource/ImageResource.hpp"
+
 #include "LmsApplication.hpp"
 #include "Filters.hpp"
 #include "TracksView.hpp"

src/ui/resource/AvConvTranscodeStreamResource.cpp

@@ -1,101 +0,0 @@
-/*
- * Copyright (C) 2013 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/>.
- */
-
-
-#include <Wt/Http/Request>
-#include <Wt/Http/Response>
-
-#include "utils/Logger.hpp"
-
-#include "AvConvTranscodeStreamResource.hpp"
-
-namespace UserInterface {
-
-AvConvTranscodeStreamResource::AvConvTranscodeStreamResource(boost::filesystem::path p, Av::TranscodeParameters parameters, Wt::WObject *parent)
-: Wt::WResource(parent),
-_filePath(p),
-_parameters( parameters )
-{
-	LMS_LOG(UI, DEBUG) << "CONSTRUCTING RESOURCE";
-}
-
-AvConvTranscodeStreamResource::~AvConvTranscodeStreamResource()
-{
-	LMS_LOG(UI, DEBUG) << "DESTRUCTING RESOURCE";
-	beingDeleted();
-}
-
-void
-AvConvTranscodeStreamResource::handleRequest(const Wt::Http::Request& request,
-		Wt::Http::Response& response)
-{
-	LMS_LOG(UI, DEBUG) << "Handling new request...";
-
-	// see if this request is for a continuation:
-	Wt::Http::ResponseContinuation *continuation = request.continuation();
-
-	LMS_LOG(UI, DEBUG) << "Handling new request. Continuation = " << continuation;
-
-	std::shared_ptr<Av::Transcoder> transcoder;
-	if (continuation)
-		transcoder = boost::any_cast<std::shared_ptr<Av::Transcoder> >(continuation->data());
-
-	if (!transcoder)
-	{
-		LMS_LOG(UI, DEBUG) << "Launching transcoder";
-		transcoder = std::make_shared<Av::Transcoder>( _filePath, _parameters);
-
-		LMS_LOG(UI, DEBUG) << "Mime type set to '" << Av::encoding_to_mimetype(_parameters.getEncoding());
-		response.setMimeType( Av::encoding_to_mimetype(_parameters.getEncoding()) );
-
-		if (!transcoder->start())
-		{
-			LMS_LOG(UI, ERROR) << "Cannot start transcoder";
-			return;
-		}
-	}
-
-	if (!transcoder->isComplete())
-	{
-		std::vector<unsigned char> data;
-		data.reserve(_bufferSize);
-
-		transcoder->process(data, _bufferSize);
-
-		// Give the client all the output data
-		response.out().write(reinterpret_cast<char*>(&data[0]), data.size());
-
-		LMS_LOG(UI, DEBUG) << "Written " << data.size() << " bytes! complete = " << std::boolalpha << transcoder->isComplete();
-
-		if (!response.out())
-			LMS_LOG(UI, ERROR) << "Write failed!";
-	}
-
-	if (!transcoder->isComplete() && response.out()) {
-		continuation = response.createContinuation();
-		continuation->setData(transcoder);
-		LMS_LOG(UI, DEBUG) << "Continuation set to " << continuation;
-	}
-	else
-		LMS_LOG(UI, DEBUG) << "No more data!";
-}
-
-} // namespace UserInterface
-
-

src/ui/resource/AvConvTranscodeStreamResource.hpp

@@ -1,51 +0,0 @@
-/*
- * Copyright (C) 2013 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/>.
- */
-
-#ifndef AVCONV_TRANSCODE_STREAM_RESOURCE_HPP
-#define AVCONV_TRANSCODE_STREAM_RESOURCE_HPP
-
-#include <iostream>
-#include <memory>
-
-#include <Wt/WResource>
-
-#include "av/AvTranscoder.hpp"
-
-namespace UserInterface {
-
-class AvConvTranscodeStreamResource : public Wt::WResource
-{
-	public:
-		AvConvTranscodeStreamResource(boost::filesystem::path p, Av::TranscodeParameters parameters, Wt::WObject *parent = 0);
-		~AvConvTranscodeStreamResource();
-
-		void handleRequest(const Wt::Http::Request& request,
-				Wt::Http::Response& response);
-
-	private:
-		boost::filesystem::path		_filePath;
-		Av::TranscodeParameters		_parameters;
-
-		static const std::size_t	_bufferSize = 8192;
-};
-
-} // namespace UserInterface
-
-#endif
-

src/ui/resource/TranscodeResource.cpp

@@ -41,15 +41,13 @@ TranscodeResource:: ~TranscodeResource()
 }
 
 std::string
-TranscodeResource::getUrl(Database::Track::id_type trackId, Av::Encoding encoding, std::size_t offset, std::vector<std::size_t> streamIds) const
+TranscodeResource::getUrl(Database::Track::id_type trackId, Av::Encoding encoding, boost::posix_time::time_duration offset, boost::optional<std::size_t> streamId) const
 {
 	std::string res = url()+ "&trackid=" + std::to_string(trackId) + "&encoding=" + std::to_string(Av::encoding_to_int(encoding));
-	if (!streamIds.empty())
+	if (streamId)
-	{
+		res += "&stream=" + std::to_string(*streamId);
-		for (std::size_t streamId : streamIds)
+	res += "&offset=" + std::to_string(offset.seconds());
-			res += "&stream=" + std::to_string(streamId);
+
-	}
-	res += "&offset=" + std::to_string(offset);
 	return res;
 }
 
@@ -57,121 +55,107 @@ void
 TranscodeResource::handleRequest(const Wt::Http::Request& request,
 		Wt::Http::Response& response)
 {
-	// Retrieve parameters
+	std::shared_ptr<Av::Transcoder> transcoder;
-	const std::string *trackIdStr = request.getParameter("trackid");
-	const std::string *offsetStr = request.getParameter("offset");
-	const std::string *encodingStr = request.getParameter("encoding");
-	std::vector<std::string> streams = request.getParameterValues ("stream");
 
 	LMS_LOG(UI, DEBUG) << "Handling new request...";
 
-	try
+	// First, see if this request is for a continuation
+	Wt::Http::ResponseContinuation *continuation = request.continuation();
+	if (continuation)
 	{
-		std::shared_ptr<Av::Transcoder> transcoder;
+		LMS_LOG(UI, DEBUG) << "Continuation! " << continuation ;
-
+		transcoder = boost::any_cast<std::shared_ptr<Av::Transcoder>>(continuation->data());
-		// First, see if this request is for a continuation
-		Wt::Http::ResponseContinuation *continuation = request.continuation();
-		if (continuation)
-		{
-			LMS_LOG(UI, DEBUG) << "Continuation! " << continuation ;
-			transcoder = boost::any_cast<std::shared_ptr<Av::Transcoder> >(continuation->data());
-			if (!transcoder)
-			{
-				LMS_LOG(UI, ERROR) << "No transcoder set -> abort!";
-				return;
-			}
-		}
-		else
-		{
-			LMS_LOG(UI, DEBUG) << "No continuation yet";
-
-			if (!trackIdStr
-				|| !offsetStr
-				|| !encodingStr)
-			{
-				LMS_LOG(UI, ERROR) << "Missing transcode parameter";
-				return;
-			}
-
-			Database::Track::id_type trackId = std::stol(*trackIdStr);
-
-			// transactions are not thread safe
-			{
-				Wt::WApplication::UpdateLock lock(LmsApplication::instance());
-
-				Wt::Dbo::Transaction transaction(_db.getSession());
-
-				Database::User::pointer user = _db.getCurrentUser();
-				Database::Track::pointer track = Database::Track::getById(_db.getSession(), trackId);
-
-				if (!track)
-				{
-					LMS_LOG(UI, ERROR) << "Missing track";
-					return;
-				}
-
-				if (!user)
-				{
-					LMS_LOG(UI, ERROR) << "Missing user";
-					return;
-				}
-
-				Av::TranscodeParameters parameters;
-
-				parameters.setOffset(boost::posix_time::seconds(std::stol(*offsetStr)));
-				parameters.setEncoding(Av::encoding_from_int(std::stol(*encodingStr)));
-				parameters.setBitrate(Av::Stream::Type::Audio, user->getAudioBitrate() );
-				for (std::string strStream: streams)
-				{
-					LMS_LOG(UI, DEBUG) << "Added stream " << std::stol(strStream);
-					parameters.addStream(std::stol(strStream));
-				}
-
-				LMS_LOG(UI, DEBUG) << "Offset set to " << parameters.getOffset();
-				transcoder = std::make_shared<Av::Transcoder>(track->getPath(), parameters);
-			}
-
-			std::string mimeType = Av::encoding_to_mimetype(transcoder->getParameters().getEncoding());
-
-			LMS_LOG(UI, DEBUG) << "Mime type set to '" << mimeType << "'";
-			response.setMimeType(mimeType);
-
-			if (!transcoder->start())
-			{
-				LMS_LOG(UI, ERROR) << "Cannot start transcoder";
-				return;
-			}
-
-			LMS_LOG(UI, DEBUG) << "Transcoder started";
-		}
-
-		if (!transcoder->isComplete())
-		{
-			std::vector<unsigned char> data;
-			data.reserve(_chunkSize);
-
-			transcoder->process(data, _chunkSize);
-
-			response.out().write(reinterpret_cast<char*>(&data[0]), data.size());
-			LMS_LOG(UI, DEBUG) << "Written " << data.size() << " bytes! complete = " << std::boolalpha << transcoder->isComplete();
-
-			if (!response.out())
-			{
-				LMS_LOG(UI, ERROR) << "Write failed!";
-			}
-		}
-
-		if (!transcoder->isComplete() && response.out()) {
-			continuation = response.createContinuation();
-			continuation->setData(transcoder);
-		}
-		else
-			LMS_LOG(UI, DEBUG) << "No more data!";
 	}
-	catch (std::invalid_argument& e)
+	else
 	{
-		LMS_LOG(UI, ERROR) << "Invalid argument: " << e.what();
+		Database::Track::id_type trackId;
+		Av::TranscodeParameters parameters;
+
+		LMS_LOG(UI, DEBUG) << "No continuation yet";
+		try
+		{
+			auto trackIdStr = request.getParameter("trackid");
+			if (!trackIdStr)
+			{
+				LMS_LOG(UI, ERROR) << "Missing trackid transcode parameter!";
+				return;
+			}
+			trackId = std::stol(*request.getParameter("trackid"));
+
+			auto offsetStr = request.getParameter("offset");
+			if (offsetStr)
+				parameters.offset = boost::posix_time::seconds(std::stol(*offsetStr));
+
+			auto encodingStr = request.getParameter("encoding");
+			if (encodingStr)
+				parameters.encoding = Av::encoding_from_int(std::stol(*encodingStr));
+
+			auto streamStr = request.getParameter("stream");
+			if (streamStr)
+				parameters.stream = std::stol(*streamStr);
+		}
+		catch (std::exception &e)
+		{
+			LMS_LOG(UI, ERROR) << "Exception while handling URL parameters: " << e.what();
+			return;
+		}
+
+		// transactions are not thread safe
+		{
+			Wt::WApplication::UpdateLock lock(LmsApplication::instance());
+
+			Wt::Dbo::Transaction transaction(_db.getSession());
+
+			Database::User::pointer user = _db.getCurrentUser();
+			Database::Track::pointer track = Database::Track::getById(_db.getSession(), trackId);
+
+			if (!track)
+			{
+				LMS_LOG(UI, ERROR) << "Missing track";
+				return;
+			}
+
+			parameters.bitrate = user->getAudioBitrate();
+			transcoder = std::make_shared<Av::Transcoder>(track->getPath(), parameters);
+		}
+
+		std::string mimeType = Av::encoding_to_mimetype(transcoder->getParameters().encoding);
+
+		LMS_LOG(UI, DEBUG) << "Mime type set to '" << mimeType << "'";
+		response.setMimeType(mimeType);
+
+		if (!transcoder->start())
+		{
+			LMS_LOG(UI, ERROR) << "Cannot start transcoder";
+			return;
+		}
+
+		LMS_LOG(UI, DEBUG) << "Transcoder started";
 	}
+
+	if (!transcoder->isComplete())
+	{
+		std::vector<unsigned char> data;
+		data.reserve(_chunkSize);
+
+		transcoder->process(data, _chunkSize);
+
+		response.out().write(reinterpret_cast<char*>(&data[0]), data.size());
+		LMS_LOG(UI, DEBUG) << "Written " << data.size() << " bytes! complete = " << std::boolalpha << transcoder->isComplete();
+
+		if (!response.out())
+		{
+			LMS_LOG(UI, ERROR) << "Write failed!";
+		}
+	}
+
+	if (!transcoder->isComplete() && response.out())
+	{
+		continuation = response.createContinuation();
+		continuation->setData(transcoder);
+	}
+	else
+		LMS_LOG(UI, DEBUG) << "No more data!";
 }
 
 } // namespace UserInterface

src/ui/resource/TranscodeResource.hpp

@@ -21,6 +21,8 @@
 
 #include <mutex>
 
+#include <boost/optional.hpp>
+
 #include <Wt/WResource>
 
 #include "av/AvTranscoder.hpp"
@@ -35,7 +37,7 @@ class TranscodeResource : public Wt::WResource
 		TranscodeResource(Database::Handler& db, Wt::WObject *parent);
 		~TranscodeResource();
 
-		std::string getUrl(Database::Track::id_type trackId, Av::Encoding encoding = Av::Encoding::OGA, size_t offset_secs = 0, std::vector<size_t> streamIds = {}) const;
+		std::string getUrl(Database::Track::id_type trackId, Av::Encoding encoding, boost::posix_time::time_duration offset, boost::optional<size_t> stream = boost::none) const;
 
 		void handleRequest(const Wt::Http::Request& request,
 				Wt::Http::Response& response);