HeavenStudio/Assets/Scripts/Util/SavWav.cs

189 lines
5.9 KiB
C#

// Copyright (c) 2012 Calvin Rien
// http://the.darktable.com
//
// This software is provided 'as-is', without any express or implied warranty. In
// no event will the authors be held liable for any damages arising from the use
// of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it freely,
// subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented; you must not claim
// that you wrote the original software. If you use this software in a product,
// an acknowledgment in the product documentation would be appreciated but is not
// required.
//
// 2. Altered source versions must be plainly marked as such, and must not be
// misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source distribution.
//
// =============================================================================
//
// derived from Gregorio Zanon's script
// http://forum.unity3d.com/threads/119295-Writing-AudioListener.GetOutputData-to-wav-problem?p=806734&viewfull=1#post806734
//
// Fork by R-WebsterNoble
// Optimized! Now 20 times quicker
// Easy to get byte[] instead of saving file
// Note: GetWav() with trimming returns the full buffer with a load of zeros on the end.
// Use the length out parameter to know where the data stops.
//
// RHeavenStudio
// modified to use temporary cache path instead of persistent data path
using System;
using System.IO;
using System.Text;
using UnityEngine;
public static class SavWav
{
private const uint HeaderSize = 44;
private const float RescaleFactor = 32767; //to convert float to Int16
public static void Save(string filename, AudioClip clip, bool trim = false)
{
if (!filename.ToLower().EndsWith(".wav"))
{
filename += ".wav";
}
var filepath = Path.Combine(Application.temporaryCachePath, filename);
// Make sure directory exists if user is saving to sub dir.
if (!Directory.Exists(Path.GetDirectoryName(filepath)))
{
Directory.CreateDirectory(Path.GetDirectoryName(filepath));
}
using (var fileStream = new FileStream(filepath, FileMode.Create))
using (var writer = new BinaryWriter(fileStream))
{
var wav = GetWav(clip, out var length, trim);
writer.Write(wav, 0, (int)length);
fileStream.Close();
fileStream.Dispose();
}
}
public static byte[] GetWav(AudioClip clip, out uint length, bool trim = false)
{
var data = ConvertAndWrite(clip, out length, out var samples, trim);
WriteHeader(data, clip, length, samples);
return data;
}
private static byte[] ConvertAndWrite(AudioClip clip, out uint length, out uint samplesAfterTrimming, bool trim)
{
var samples = new float[clip.samples * clip.channels];
clip.GetData(samples, 0);
var sampleCount = samples.Length;
var start = 0;
var end = sampleCount - 1;
if (trim)
{
for (var i = 0; i < sampleCount; i++)
{
if ((short)(samples[i] * RescaleFactor) == 0)
continue;
start = i;
break;
}
for (var i = sampleCount -1; i >= 0; i--)
{
if ((short)(samples[i] * RescaleFactor) == 0)
continue;
end = i;
break;
}
}
var buffer = new byte[(sampleCount * 2) + HeaderSize];
var p = HeaderSize;
for (var i = start; i <= end; i++)
{
var value = (short) (samples[i] * RescaleFactor);
buffer[p++] = (byte) (value >> 0);
buffer[p++] = (byte) (value >> 8);
}
length = p;
samplesAfterTrimming = (uint) (end - start + 1);
return buffer;
}
private static void AddDataToBuffer(byte[] buffer, ref uint offset, byte[] addBytes)
{
foreach (var b in addBytes)
{
buffer[offset++] = b;
}
}
private static void WriteHeader(byte[] stream, AudioClip clip, uint length, uint samples)
{
var hz = (uint)clip.frequency;
var channels = (ushort)clip.channels;
var offset = 0u;
var riff = Encoding.UTF8.GetBytes("RIFF");
AddDataToBuffer(stream, ref offset, riff);
var chunkSize = BitConverter.GetBytes(length - 8);
AddDataToBuffer(stream, ref offset, chunkSize);
var wave = Encoding.UTF8.GetBytes("WAVE");
AddDataToBuffer(stream, ref offset, wave);
var fmt = Encoding.UTF8.GetBytes("fmt ");
AddDataToBuffer(stream, ref offset, fmt);
var subChunk1 = BitConverter.GetBytes(16u);
AddDataToBuffer(stream, ref offset, subChunk1);
const ushort two = 2;
const ushort one = 1;
var audioFormat = BitConverter.GetBytes(one);
AddDataToBuffer(stream, ref offset, audioFormat);
var numChannels = BitConverter.GetBytes(channels);
AddDataToBuffer(stream, ref offset, numChannels);
var sampleRate = BitConverter.GetBytes(hz);
AddDataToBuffer(stream, ref offset, sampleRate);
var byteRate = BitConverter.GetBytes(hz * channels * 2); // sampleRate * bytesPerSample*number of channels, here 44100*2*2
AddDataToBuffer(stream, ref offset, byteRate);
var blockAlign = (ushort)(channels * 2);
AddDataToBuffer(stream, ref offset, BitConverter.GetBytes(blockAlign));
ushort bps = 16;
var bitsPerSample = BitConverter.GetBytes(bps);
AddDataToBuffer(stream, ref offset, bitsPerSample);
var dataString = Encoding.UTF8.GetBytes("data");
AddDataToBuffer(stream, ref offset, dataString);
var subChunk2 = BitConverter.GetBytes(samples * 2);
AddDataToBuffer(stream, ref offset, subChunk2);
}
}