diff options
Diffstat (limited to 'src/plugins/Input/opus/opusproperties.cpp')
| -rw-r--r-- | src/plugins/Input/opus/opusproperties.cpp | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/src/plugins/Input/opus/opusproperties.cpp b/src/plugins/Input/opus/opusproperties.cpp new file mode 100644 index 000000000..89ede973d --- /dev/null +++ b/src/plugins/Input/opus/opusproperties.cpp @@ -0,0 +1,161 @@ +/*************************************************************************** + copyright : (C) 2012 by Lukáš Lalinský + email : lalinsky@gmail.com + + copyright : (C) 2002 - 2008 by Scott Wheeler + email : wheeler@kde.org + (original Vorbis implementation) + ***************************************************************************/ + +/*************************************************************************** + * This library is free software; you can redistribute it and/or modify * + * it under the terms of the GNU Lesser General Public License version * + * 2.1 as published by the Free Software Foundation. * + * * + * This library 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 * + * Lesser General Public License for more details. * + * * + * You should have received a copy of the GNU Lesser General Public * + * License along with this library; if not, write to the Free Software * + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA * + * 02110-1301 USA * + * * + * Alternatively, this file is available under the Mozilla Public * + * License Version 1.1. You may obtain a copy of the License at * + * http://www.mozilla.org/MPL/ * + ***************************************************************************/ + +#include <taglib/tstring.h> +#include "tdebug.h" + +#include <taglib/oggpageheader.h> + +#include "opusproperties.h" +#include "opusfile.h" + +using namespace TagLib; +using namespace TagLib::Ogg; + +class Opus::Properties::PropertiesPrivate +{ +public: + PropertiesPrivate(File *f, ReadStyle s) : + file(f), + style(s), + length(0), + inputSampleRate(0), + channels(0), + opusVersion(0) {} + + File *file; + ReadStyle style; + int length; + int inputSampleRate; + int channels; + int opusVersion; +}; + +//////////////////////////////////////////////////////////////////////////////// +// public members +//////////////////////////////////////////////////////////////////////////////// + +Opus::Properties::Properties(File *file, ReadStyle style) : AudioProperties(style) +{ + d = new PropertiesPrivate(file, style); + read(); +} + +Opus::Properties::~Properties() +{ + delete d; +} + +int Opus::Properties::length() const +{ + return d->length; +} + +int Opus::Properties::bitrate() const +{ + return 0; +} + +int Opus::Properties::sampleRate() const +{ + // Opus can decode any stream at a sample rate of 8, 12, 16, 24, or 48 kHz, + // so there is no single sample rate. Let's assume it's the highest + // possible. + return 48000; +} + +int Opus::Properties::channels() const +{ + return d->channels; +} + +int Opus::Properties::inputSampleRate() const +{ + return d->inputSampleRate; +} + +int Opus::Properties::opusVersion() const +{ + return d->opusVersion; +} + +//////////////////////////////////////////////////////////////////////////////// +// private members +//////////////////////////////////////////////////////////////////////////////// + +void Opus::Properties::read() +{ + // Get the identification header from the Ogg implementation. + + // http://tools.ietf.org/html/draft-terriberry-oggopus-01#section-5.1 + + ByteVector data = d->file->packet(0); + + // *Magic Signature* + int pos = 8; + + // *Version* (8 bits, unsigned) + d->opusVersion = uchar(data.at(pos)); + pos += 1; + + // *Output Channel Count* 'C' (8 bits, unsigned) + d->channels = uchar(data.at(pos)); + pos += 1; + + // *Pre-skip* (16 bits, unsigned, little endian) + ushort preSkip = data.mid(pos, 2).toUShort(false); + pos += 2; + + // *Input Sample Rate* (32 bits, unsigned, little endian) + d->inputSampleRate = data.mid(pos, 4).toUInt(false); + pos += 4; + + // *Output Gain* (16 bits, signed, little endian) + pos += 2; + + // *Channel Mapping Family* (8 bits, unsigned) + pos += 1; + + const Ogg::PageHeader *first = d->file->firstPageHeader(); + const Ogg::PageHeader *last = d->file->lastPageHeader(); + + if(first && last) { + long long start = first->absoluteGranularPosition(); + long long end = last->absoluteGranularPosition(); + + if(start >= 0 && end >= 0) + d->length = (int) ((end - start - preSkip) / 48000); + else { + debug("Opus::Properties::read() -- The PCM values for the start or " + "end of this file was incorrect."); + } + } + else + debug("Opus::Properties::read() -- Could not find valid first and last Ogg pages."); +} |