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/* ScummVM Tools
*
* ScummVM Tools is the legal property of its developers, whose
* names are too numerous to list here. Please refer to the
* COPYRIGHT file distributed with this source distribution.
*
* 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 SOUND_AUDIOSTREAM_H
#define SOUND_AUDIOSTREAM_H
#include "common/scummsys.h"
namespace Audio {
class Mixer {
public:
enum {
/** unsigned samples (default: signed) */
FLAG_UNSIGNED = 1 << 0,
/** sound is 16 bits wide (default: 8bit) */
FLAG_16BITS = 1 << 1,
/** sample is little endian (default: big endian) */
FLAG_LITTLE_ENDIAN = 1 << 2,
/** sound is in stereo (default: mono) */
FLAG_STEREO = 1 << 3,
/** reverse the left and right stereo channel */
FLAG_REVERSE_STEREO = 1 << 4,
/** sound buffer is freed automagically at the end of playing */
FLAG_AUTOFREE = 1 << 5,
/** loop the audio */
FLAG_LOOP = 1 << 6
};
};
/**
* Generic input stream for the resampling code.
*/
class AudioStream {
public:
virtual ~AudioStream() {}
/**
* Fill the given buffer with up to numSamples samples.
* Returns the actual number of samples read, or -1 if
* a critical error occurred (note: you *must* check if
* this value is less than what you requested, this can
* happen when the stream is fully used up).
*
* Data has to be in native endianess, 16 bit per sample, signed.
* For stereo stream, buffer will be filled with interleaved
* left and right channel samples, starting with a left sample.
* Furthermore, the samples in the left and right are summed up.
* So if you request 4 samples from a stereo stream, you will get
* a total of two left channel and two right channel samples.
*/
virtual int readBuffer(int16 *buffer, const int numSamples) = 0;
/** Is this a stereo stream? */
virtual bool isStereo() const = 0;
/**
* End of data reached? If this returns true, it means that at this
* time there is no data available in the stream. However there may be
* more data in the future.
* This is used by e.g. a rate converter to decide whether to keep on
* converting data or stop.
*/
virtual bool endOfData() const = 0;
/**
* End of stream reached? If this returns true, it means that all data
* in this stream is used up and no additional data will appear in it
* in the future.
* This is used by the mixer to decide whether a given stream shall be
* removed from the list of active streams (and thus be destroyed).
* By default this maps to endOfData()
*/
virtual bool endOfStream() const { return endOfData(); }
/** Sample rate of the stream. */
virtual int getRate() const = 0;
};
AudioStream *makeLinearInputStream(int rate, byte flags, const byte *ptr, uint32 len, uint32 loopOffset, uint32 loopLen);
/**
* An audio stream to which additional data can be appended on-the-fly.
* Used by SMUSH, iMuseDigital, and the Kyrandia 3 VQA player.
*/
class AppendableAudioStream : public Audio::AudioStream {
public:
virtual void append(const byte *data, uint32 len) = 0;
virtual void finish() = 0;
};
AppendableAudioStream *makeAppendableAudioStream(int rate, byte _flags, uint32 len);
// This used to be an inline template function, but
// buggy template function handling in MSVC6 forced
// us to go with the macro approach. So far this is
// the only template function that MSVC6 seemed to
// compile incorrectly. Knock on wood.
#define READ_ENDIAN_SAMPLE(is16Bit, isUnsigned, ptr, isLE) \
((is16Bit ? (isLE ? READ_LE_UINT16(ptr) : READ_BE_UINT16(ptr)) : (*ptr << 8)) ^ (isUnsigned ? 0x8000 : 0))
} // End of namespace Audio
#endif
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