mpd/src/pcm/FormatConverter.hxx
2022-07-14 17:59:35 +02:00

80 lines
2.0 KiB
C++

/*
* Copyright 2003-2022 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.
*/
#ifndef MPD_PCM_FORMAT_CONVERTER_HXX
#define MPD_PCM_FORMAT_CONVERTER_HXX
#include "SampleFormat.hxx"
#include "Buffer.hxx"
#include "Dither.hxx"
#include <span>
#ifndef NDEBUG
#include <cassert>
#endif
/**
* A class that converts samples from one format to another.
*/
class PcmFormatConverter {
SampleFormat src_format, dest_format;
PcmBuffer buffer;
PcmDither dither;
public:
#ifndef NDEBUG
PcmFormatConverter() noexcept
:src_format(SampleFormat::UNDEFINED),
dest_format(SampleFormat::UNDEFINED) {}
~PcmFormatConverter() noexcept {
assert(src_format == SampleFormat::UNDEFINED);
assert(dest_format == SampleFormat::UNDEFINED);
}
#endif
/**
* Opens the object, prepare for Convert().
*
* Throws std::runtime_error on error.
*
* @param src_format the sample format of incoming data
* @param dest_format the sample format of outgoing data
*/
void Open(SampleFormat src_format, SampleFormat dest_format);
/**
* Closes the object. After that, you may call Open() again.
*/
void Close() noexcept;
/**
* Convert a block of PCM data.
*
* @param src the input buffer
* @return the destination buffer
*/
[[gnu::pure]]
std::span<const std::byte> Convert(std::span<const std::byte> src) noexcept;
};
#endif