//! \file AudioVOC.cs //! \date 2023 Oct 19 //! \brief AyPio ADPCM-compressed audio. // // Copyright (C) 2023 by morkt // // Permission is hereby granted, free of charge, to any person obtaining a copy // of this software and associated documentation files (the "Software"), to // deal in the Software without restriction, including without limitation the // rights to use, copy, modify, merge, publish, distribute, sublicense, and/or // sell copies of the Software, and to permit persons to whom the Software is // furnished to do so, subject to the following conditions: // // The above copyright notice and this permission notice shall be included in // all copies or substantial portions of the Software. // // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS // IN THE SOFTWARE. // using GameRes.Utility; using System.ComponentModel.Composition; namespace GameRes.Formats.AyPio { [Export(typeof(AudioFormat))] public class VocAudio : AudioFormat { public override string Tag => "VOC/UK2"; public override string Description => "UK2 engine compressed audio"; public override uint Signature => 0x81564157; // 'WAV\x81' public override bool CanWrite => false; public override SoundInput TryOpen (IBinaryStream file) { var header = file.ReadHeader (0x3C); if (!header.AsciiEqual (0x38, "RIFF")) return null; var decoder = new VocDecoder (file); var samples = decoder.Decode(); var stream = new BinMemoryStream (samples, file.Name); file.Dispose(); return new RawPcmInput (stream, decoder.Format); } } internal sealed class VocDecoder { IBinaryStream m_input; int m_sample_count; byte m_channels; byte m_bits_per_sample; byte[] m_prev_sample = new byte[2]; long m_start_pos; public WaveFormat Format { get; private set; } public VocDecoder (IBinaryStream input) { m_input = input; var header = input.ReadHeader (0x38); Format = new WaveFormat { FormatTag = header.ToUInt16 (0x21), Channels = header.ToUInt16 (0x23), SamplesPerSecond = header.ToUInt32 (0x25), AverageBytesPerSecond = header.ToUInt32 (0x29), BlockAlign = header.ToUInt16 (0x2D), BitsPerSample = header.ToUInt16 (0x2F), }; m_sample_count = header.ToInt32 (0x18); m_channels = header[8]; m_prev_sample[0] = header[0xC]; m_prev_sample[1] = header[0x10]; m_bits_per_sample = header[0x20]; m_output = new byte[m_sample_count << 1]; m_output[0] = header[0xA]; m_output[1] = header[0xB]; m_output[2] = header[0xE]; m_output[3] = header[0xF]; m_start_pos = header.ToUInt32 (4) + header.ToUInt32 (0x14); } byte[] m_output; int[] m_samples; int m_src; public byte[] Decode () { m_input.Position = m_start_pos; m_src = 0; BuildSamples(); int count = m_sample_count - m_channels; int src = 0; int pos = 0; while (src < count) { byte sample = GetSample(); int v7 = sample & 7; int channel; if (m_channels == 1 || (src & 1) == 0) channel = 0; else channel = 1; byte prev = m_prev_sample[channel]; int s = m_samples[89 * v7 + prev]; if ((sample & 8) != 0) s = -s; s += m_output.ToInt16 (pos); pos += 2; LittleEndian.Pack (Clamp (s), m_output, pos); int p = IndexTable[v7] + prev; if (p < 0) p = 0; else if (p > 88) p = 88; m_prev_sample[channel] = (byte)p; ++src; } return m_output; } byte m_current_sample; byte GetSample () { if (0 == (m_src & 1)) m_current_sample = m_input.ReadUInt8(); ++m_src; byte sample = m_current_sample; m_current_sample >>= 4; return sample &= 0xF; } short Clamp (int sample) { if (sample > 0x7FFF) sample = 0x7FFF; else if (sample < -0x8000) sample = -0x8000; return (short)sample; } void BuildSamples () { int b = 1 << (m_bits_per_sample - 1); int i = 0; m_samples = new int[89 * b]; while (i < 89) { int ii = i; int j = 0; while (j < b) { double d = 0.0; int a = 1; int c = b; do { if (j % a >= a / 2) { d += (double)StepTable[ii] / (double)c; } a <<= 1; c >>= 1; } while (a <= b); ++j; m_samples[i] = (int)d; i += 89; } i = ii + 1; } } static readonly short[] StepTable = { 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x10, 0x11, 0x13, 0x15, 0x17, 0x19, 0x1C, 0x1F, 0x22, 0x25, 0x29, 0x2D, 0x32, 0x37, 0x3C, 0x42, 0x49, 0x50, 0x58, 0x61, 0x6B, 0x76, 0x82, 0x8F, 0x9D, 0x0AD, 0x0BE, 0x0D1, 0x0E6, 0x0FD, 0x117, 0x133, 0x151, 0x173, 0x198, 0x1C1, 0x1EE, 0x220, 0x256, 0x292, 0x2D4, 0x31C, 0x36C, 0x3C3, 0x424, 0x48E, 0x502, 0x583, 0x610, 0x6AB, 0x756, 0x812, 0x8E0, 0x9C3, 0x0ABD, 0x0BD0, 0x0CFF, 0x0E4C, 0x0FBA, 0x114C, 0x1307, 0x14EE, 0x1706, 0x1954, 0x1BDC, 0x1EA5, 0x21B6, 0x2515, 0x28CA, 0x2CDF, 0x315B, 0x364B, 0x3BB9, 0x41B2, 0x4844, 0x4F7E, 0x5771, 0x602F, 0x69CE, 0x7462, 0x7FFF, }; static readonly sbyte[] IndexTable = { -1, -1, -1, -1, 1, 2, 3, 4 }; } }