From 9cea3d393f0c3657f3caef72a13dce5594581bdd Mon Sep 17 00:00:00 2001 From: Max Horn Date: Sun, 9 Jan 2005 15:49:43 +0000 Subject: Added shared code to load WAV(E) data from arbitrary seekable streams (files or memory) svn-id: r16502 --- sound/wave.cpp | 162 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 162 insertions(+) create mode 100644 sound/wave.cpp (limited to 'sound/wave.cpp') diff --git a/sound/wave.cpp b/sound/wave.cpp new file mode 100644 index 0000000000..0388d0a757 --- /dev/null +++ b/sound/wave.cpp @@ -0,0 +1,162 @@ +/* ScummVM - Scumm Interpreter + * Copyright (C) 2001 Ludvig Strigeus + * Copyright (C) 2001-2005 The ScummVM project + * + * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * $Header$ + * + */ + +#include "stdafx.h" +#include "common/util.h" +#include "common/stream.h" + +#include "sound/audiostream.h" +#include "sound/mixer.h" +#include "sound/wave.h" + +bool loadWAVFromStream(Common::SeekableReadStream &stream, int &size, int &rate, byte &flags) { + const uint32 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; + } + + uint32 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, "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 + // See 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 0 + printf("WAVE information:\n"); + printf(" total size: %d\n", wavLength); + printf(" fmt size: %d\n", fmtLength); + printf(" type: %d\n", type); + printf(" numChannels: %d\n", numChannels); + printf(" samplesPerSec: %d\n", samplesPerSec); + printf(" avgBytesPerSec: %d\n", avgBytesPerSec); + printf(" blockAlign: %d\n", blockAlign); + printf(" bitsPerSample: %d\n", bitsPerSample); +#endif + + if (type != 1) { + warning("getWavInfo: only PCM data is supported (type %d)", type); + return false; + } + + if (blockAlign != numChannels * bitsPerSample / 8) { + debug(0, "getWavInfo: blockAlign is invalid"); + } + + if (avgBytesPerSec != samplesPerSec * blockAlign) { + debug(0, "getWavInfo: avgBytesPerSec is invalid"); + } + + // Prepare the return values. + rate = samplesPerSec; + + flags = 0; + if (bitsPerSample == 8) // 8 bit data is unsigned + flags |= SoundMixer::FLAG_UNSIGNED; + else if (bitsPerSample == 16) // 16 bit data is signed + flags |= SoundMixer::FLAG_16BITS; + else { + warning("getWavInfo: unsupported bitsPerSample %d", bitsPerSample); + return false; + } + + if (numChannels == 2) + flags |= SoundMixer::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 + printf(" found a '%s' tag of size %d\n", buf, offset); +#endif + } while (memcmp(buf, "data", 4) != 0); + + // Stream now points at 'offset' bytes of sample data... + size = offset; + + return true; +} + +AudioStream *makeWAVStream(Common::SeekableReadStream &stream) { + int size, rate; + byte flags; + + if (!loadWAVFromStream(stream, size, rate, flags)) + return 0; + + byte *data = (byte *)malloc(size); + assert(data); + stream.read(data, size); + flags |= SoundMixer::FLAG_AUTOFREE; + + return makeLinearInputStream(rate, flags, data, size, 0, 0); +} -- cgit v1.2.3