mpd/src/lib/xiph/FlacStreamMetadata.cxx
2021-12-06 09:28:36 +01:00

148 lines
3.8 KiB
C++

/*
* Copyright 2003-2021 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 "FlacStreamMetadata.hxx"
#include "FlacAudioFormat.hxx"
#include "ScanVorbisComment.hxx"
#include "pcm/CheckAudioFormat.hxx"
#include "tag/Handler.hxx"
#include "tag/Builder.hxx"
#include "tag/Tag.hxx"
#include "tag/MixRampInfo.hxx"
#include "tag/MixRampParser.hxx"
#include "tag/ReplayGainInfo.hxx"
#include "tag/ReplayGainParser.hxx"
#include "util/StringView.hxx"
#include <cassert>
static StringView
ToStringView(const FLAC__StreamMetadata_VorbisComment_Entry &entry) noexcept
{
return {(const char *)entry.entry, entry.length};
}
bool
flac_parse_replay_gain(ReplayGainInfo &rgi,
const FLAC__StreamMetadata_VorbisComment &vc)
{
rgi.Clear();
bool found = false;
const auto *comments = vc.comments;
for (FLAC__uint32 i = 0, n = vc.num_comments; i < n; ++i)
if (ParseReplayGainVorbis(rgi, ToStringView(comments[i])))
found = true;
return found;
}
MixRampInfo
flac_parse_mixramp(const FLAC__StreamMetadata_VorbisComment &vc)
{
MixRampInfo mix_ramp;
const auto *comments = vc.comments;
for (FLAC__uint32 i = 0, n = vc.num_comments; i < n; ++i)
ParseMixRampVorbis(mix_ramp, ToStringView(comments[i]));
return mix_ramp;
}
static void
flac_scan_comments(const FLAC__StreamMetadata_VorbisComment *comment,
TagHandler &handler) noexcept
{
for (unsigned i = 0; i < comment->num_comments; ++i)
ScanVorbisComment(ToStringView(comment->comments[i]), handler);
}
gcc_pure
static inline SongTime
flac_duration(const FLAC__StreamMetadata_StreamInfo *stream_info) noexcept
{
assert(stream_info->sample_rate > 0);
return SongTime::FromScale<uint64_t>(stream_info->total_samples,
stream_info->sample_rate);
}
static void
Scan(const FLAC__StreamMetadata_StreamInfo &stream_info,
TagHandler &handler) noexcept
{
if (stream_info.sample_rate > 0)
handler.OnDuration(flac_duration(&stream_info));
try {
handler.OnAudioFormat(CheckAudioFormat(stream_info.sample_rate,
FlacSampleFormat(stream_info.bits_per_sample),
stream_info.channels));
} catch (...) {
}
}
static void
Scan(const FLAC__StreamMetadata_Picture &picture, TagHandler &handler) noexcept
{
if (!handler.WantPicture())
return;
if (picture.mime_type != nullptr &&
StringIsEqual(picture.mime_type, "-->"))
/* this is a URL, not image data */
return;
handler.OnPicture(picture.mime_type,
{picture.data, picture.data_length});
}
void
flac_scan_metadata(const FLAC__StreamMetadata *block,
TagHandler &handler) noexcept
{
switch (block->type) {
case FLAC__METADATA_TYPE_VORBIS_COMMENT:
flac_scan_comments(&block->data.vorbis_comment,
handler);
break;
case FLAC__METADATA_TYPE_STREAMINFO:
Scan(block->data.stream_info, handler);
break;
case FLAC__METADATA_TYPE_PICTURE:
Scan(block->data.picture, handler);
break;
default:
break;
}
}
Tag
flac_vorbis_comments_to_tag(const FLAC__StreamMetadata_VorbisComment *comment)
{
TagBuilder tag_builder;
AddTagHandler h(tag_builder);
flac_scan_comments(comment, h);
return tag_builder.Commit();
}