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/*
* Copyright 2003-2019 The Music Player Daemon Project
* http://www.musicpd.org
*
* 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, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "HdcdFilterPlugin.hxx"
#include "FfmpegFilter.hxx"
#include "filter/FilterPlugin.hxx"
#include "filter/Filter.hxx"
#include "filter/NullFilter.hxx"
#include "filter/Prepared.hxx"
#include "lib/ffmpeg/Filter.hxx"
#include "AudioFormat.hxx"
static constexpr const char *hdcd_graph = "hdcd";
gcc_pure
static bool
MaybeHdcd(const AudioFormat &audio_format) noexcept
{
return audio_format.sample_rate == 44100 &&
audio_format.format == SampleFormat::S16 &&
audio_format.channels == 2;
}
static auto
OpenHdcdFilter(AudioFormat &in_audio_format)
{
Ffmpeg::FilterGraph graph;
auto buffer_src =
Ffmpeg::FilterContext::MakeAudioBufferSource(in_audio_format,
*graph);
auto buffer_sink = Ffmpeg::FilterContext::MakeAudioBufferSink(*graph);
Ffmpeg::FilterInOut io_sink("out", *buffer_sink);
Ffmpeg::FilterInOut io_src("in", *buffer_src);
auto io = graph.Parse(hdcd_graph, std::move(io_sink),
std::move(io_src));
if (io.first.get() != nullptr)
throw std::runtime_error("FFmpeg filter has an open input");
if (io.second.get() != nullptr)
throw std::runtime_error("FFmpeg filter has an open output");
graph.CheckAndConfigure();
auto out_audio_format = in_audio_format;
// TODO: convert to 32 bit only if HDCD actually detected
out_audio_format.format = SampleFormat::S32;
return std::make_unique<FfmpegFilter>(in_audio_format,
out_audio_format,
std::move(graph),
std::move(buffer_src),
std::move(buffer_sink));
}
class PreparedHdcdFilter final : public PreparedFilter {
public:
/* virtual methods from class PreparedFilter */
std::unique_ptr<Filter> Open(AudioFormat &af) override;
};
std::unique_ptr<Filter>
PreparedHdcdFilter::Open(AudioFormat &audio_format)
{
if (MaybeHdcd(audio_format))
return OpenHdcdFilter(audio_format);
else
/* this cannot be HDCD, so let's copy as-is using
NullFilter */
return std::make_unique<NullFilter>(audio_format);
}
static std::unique_ptr<PreparedFilter>
hdcd_filter_init(const ConfigBlock &)
{
/* check if the graph can be parsed (and discard the
object) */
Ffmpeg::FilterGraph().Parse(hdcd_graph);
return std::make_unique<PreparedHdcdFilter>();
}
const FilterPlugin hdcd_filter_plugin = {
"hdcd",
hdcd_filter_init,
};