wave.cpp

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/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM 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.
 *
 */

#include "common/debug.h"
#include "common/textconsole.h"
#include "common/stream.h"

#include "audio/audiostream.h"
#include "audio/decoders/wave.h"
#include "audio/decoders/adpcm.h"
#include "audio/decoders/mp3.h"
#include "audio/decoders/raw.h"

namespace Audio {

// Audio Codecs
enum {
    kWaveFormatPCM = 1,
    kWaveFormatMSADPCM = 2,
    kWaveFormatMSIMAADPCM = 17,
    kWaveFormatMP3 = 85
};

bool loadWAVFromStream(Common::SeekableReadStream &stream, int &size, int &rate, byte &flags, uint16 *wavType, int *blockAlign_) {
    const int32 initialPos = stream.pos();
    byte buf[4+1];

    buf[4] = 0;

    stream.read(buf, 4);
    if (memcmp(buf, "RIFF", 4) != 0) {
        warning("getWavInfo: No 'RIFF' header");
        return false;
    }

    int32 wavLength = stream.readUint32LE();

    stream.read(buf, 4);
    if (memcmp(buf, "WAVE", 4) != 0) {
        warning("getWavInfo: No 'WAVE' header");
        return false;
    }

    stream.read(buf, 4);
    if (memcmp(buf, "fact", 4) == 0) {
        // Initial fact chunk, so skip over it
        uint32 factLen = stream.readUint32LE();
        stream.skip(factLen);
        stream.read(buf, 4);
    }

    if (memcmp(buf, "fmt ", 4) != 0) {
        warning("getWavInfo: No 'fmt' header");
        return false;
    }

    uint32 fmtLength = stream.readUint32LE();
    if (fmtLength < 16) {
        // A valid fmt chunk always contains at least 16 bytes
        warning("getWavInfo: 'fmt' header is too short");
        return false;
    }

    // Next comes the "type" field of the fmt header. Some typical
    // values for it:
    // 1  -> uncompressed PCM
    // 17 -> IMA ADPCM compressed WAVE
    // See <http://www.saettler.com/RIFFNEW/RIFFNEW.htm> for a more complete
    // list of common WAVE compression formats...
    uint16 type = stream.readUint16LE();    // == 1 for PCM data
    uint16 numChannels = stream.readUint16LE(); // 1 for mono, 2 for stereo
    uint32 samplesPerSec = stream.readUint32LE();   // in Hz
    uint32 avgBytesPerSec = stream.readUint32LE();  // == SampleRate * NumChannels * BitsPerSample/8

    uint16 blockAlign = stream.readUint16LE();  // == NumChannels * BitsPerSample/8
    uint16 bitsPerSample = stream.readUint16LE();   // 8, 16 ...
    // 8 bit data is unsigned, 16 bit data signed


    if (wavType != 0)
        *wavType = type;

    if (blockAlign_ != 0)
        *blockAlign_ = blockAlign;
#if 0
    debug("WAVE information:");
    debug("  total size: %d", wavLength);
    debug("  fmt size: %d", fmtLength);
    debug("  type: %d", type);
    debug("  numChannels: %d", numChannels);
    debug("  samplesPerSec: %d", samplesPerSec);
    debug("  avgBytesPerSec: %d", avgBytesPerSec);
    debug("  blockAlign: %d", blockAlign);
    debug("  bitsPerSample: %d", bitsPerSample);
#endif

    #ifdef USE_MAD
    if (type == kWaveFormatMP3) {
        bitsPerSample = 8;
    } else {
    #endif
        if (type != kWaveFormatPCM && type != kWaveFormatMSADPCM && type != kWaveFormatMSIMAADPCM) {
            #ifdef USE_MAD
            warning("getWavInfo: only PCM, MS ADPCM, MP3, or IMA ADPCM data is supported (type %d)", type);
            #else
            warning("getWavInfo: only PCM, MS ADPCM, or IMA ADPCM data is supported (type %d)", type);
            #endif

            return false;
        }

        if (blockAlign != numChannels * bitsPerSample / 8 && type != kWaveFormatMSADPCM) {
            debug(0, "getWavInfo: blockAlign is invalid");
        }

        if (avgBytesPerSec != samplesPerSec * blockAlign && type != kWaveFormatMSADPCM) {
            debug(0, "getWavInfo: avgBytesPerSec is invalid");
        }
    #ifdef USE_MAD
    }
    #endif

    // Prepare the return values.
    rate = samplesPerSec;

    flags = 0;
    if (bitsPerSample == 8)     // 8 bit data is unsigned
        flags |= Audio::FLAG_UNSIGNED;
    else if (bitsPerSample == 16)   // 16 bit data is signed little endian
        flags |= (Audio::FLAG_16BITS | Audio::FLAG_LITTLE_ENDIAN);
    else if (bitsPerSample == 4 && (type == kWaveFormatMSADPCM || type == kWaveFormatMSIMAADPCM))
        flags |= Audio::FLAG_16BITS;
    else {
        warning("getWavInfo: unsupported bitsPerSample %d", bitsPerSample);
        return false;
    }

    if (numChannels == 2)
        flags |= Audio::FLAG_STEREO;
    else if (numChannels != 1) {
        warning("getWavInfo: unsupported number of channels %d", numChannels);
        return false;
    }

    // It's almost certainly a WAV file, but we still need to find its
    // 'data' chunk.

    // Skip over the rest of the fmt chunk.
    int offset = fmtLength - 16;

    do {
        stream.seek(offset, SEEK_CUR);
        if (stream.pos() >= initialPos + wavLength + 8) {
            warning("getWavInfo: Can't find 'data' chunk");
            return false;
        }
        stream.read(buf, 4);
        offset = stream.readUint32LE();

#if 0
        debug("  found a '%s' tag of size %d", buf, offset);
#endif
    } while (memcmp(buf, "data", 4) != 0);

    // Stream now points at 'offset' bytes of sample data...
    size = offset;

    return true;
}

SeekableAudioStream *makeWAVStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse) {
    int size, rate;
    byte flags;
    uint16 type;
    int blockAlign;

    if (!loadWAVFromStream(*stream, size, rate, flags, &type, &blockAlign)) {
        if (disposeAfterUse == DisposeAfterUse::YES)
            delete stream;
        return 0;
    }

    if (type == kWaveFormatMSIMAADPCM) // MS IMA ADPCM
        return makeADPCMStream(stream, disposeAfterUse, size, Audio::kADPCMMSIma, rate, (flags & Audio::FLAG_STEREO) ? 2 : 1, blockAlign);
    else if (type == kWaveFormatMSADPCM) // MS ADPCM
        return makeADPCMStream(stream, disposeAfterUse, size, Audio::kADPCMMS, rate, (flags & Audio::FLAG_STEREO) ? 2 : 1, blockAlign);
    #ifdef USE_MAD
    else if (type == kWaveFormatMP3)
        return makeMP3Stream(stream, disposeAfterUse);
    #endif

    // Raw PCM, make sure the last packet is complete
    uint sampleSize = (flags & Audio::FLAG_16BITS ? 2 : 1) * (flags & Audio::FLAG_STEREO ? 2 : 1);
    if (size % sampleSize != 0) {
        warning("makeWAVStream: Trying to play a WAVE file with an incomplete PCM packet");
        size &= ~(sampleSize - 1);
    }

    // Raw PCM. Just read everything at once.
    // TODO: More elegant would be to wrap the stream.
    byte *data = (byte *)malloc(size);
    assert(data);
    stream->read(data, size);

    if (disposeAfterUse == DisposeAfterUse::YES)
        delete stream;

    return makeRawStream(data, size, rate, flags);
}

} // End of namespace Audio