unity3d:保存AudioClip到本地

男娘i 2022-05-19 13:46 540阅读 0赞

转自 [https://github.com/deadlyfingers/UnityWav][https_github.com_deadlyfingers_UnityWav]

using UnityEngine;
    using System.Text;
    using System.IO;
    using System;
    
    /// <summary>
    /// WAV utility for recording and audio playback functions in Unity.
    /// Version: 1.0 alpha 1
    ///
    /// - Use "ToAudioClip" method for loading wav file / bytes.
    /// Loads .wav (PCM uncompressed) files at 8,16,24 and 32 bits and converts data to Unity's AudioClip.
    ///
    /// - Use "FromAudioClip" method for saving wav file / bytes.
    /// Converts an AudioClip's float data into wav byte array at 16 bit.
    /// </summary>
    /// <remarks>
    /// For documentation and usage examples: https://github.com/deadlyfingers/UnityWav
    /// </remarks>
    
    public class WavUtility
    {
        // Force save as 16-bit .wav
        const int BlockSize_16Bit = 2;
    
        /// <summary>
        /// Load PCM format *.wav audio file (using Unity's Application data path) and convert to AudioClip.
        /// </summary>
        /// <returns>The AudioClip.</returns>
        /// <param name="filePath">Local file path to .wav file</param>
        public static AudioClip ToAudioClip (string filePath)
        {
            if (!filePath.StartsWith (Application.persistentDataPath) && !filePath.StartsWith (Application.dataPath)) {
                Debug.LogWarning ("This only supports files that are stored using Unity's Application data path. \nTo load bundled resources use 'Resources.Load(\"filename\") typeof(AudioClip)' method. \nhttps://docs.unity3d.com/ScriptReference/Resources.Load.html");
                return null;
            }
            byte[] fileBytes = File.ReadAllBytes (filePath);
            return ToAudioClip (fileBytes, 0);
        }
    
        public static AudioClip ToAudioClip (byte[] fileBytes, int offsetSamples = 0, string name = "wav")
        {
            //string riff = Encoding.ASCII.GetString (fileBytes, 0, 4);
            //string wave = Encoding.ASCII.GetString (fileBytes, 8, 4);
            int subchunk1 = BitConverter.ToInt32 (fileBytes, 16);
            UInt16 audioFormat = BitConverter.ToUInt16 (fileBytes, 20);
    
            // NB: Only uncompressed PCM wav files are supported.
            string formatCode = FormatCode (audioFormat);
            Debug.AssertFormat (audioFormat == 1 || audioFormat == 65534, "Detected format code '{0}' {1}, but only PCM and WaveFormatExtensable uncompressed formats are currently supported.", audioFormat, formatCode);
    
            UInt16 channels = BitConverter.ToUInt16 (fileBytes, 22);
            int sampleRate = BitConverter.ToInt32 (fileBytes, 24);
            //int byteRate = BitConverter.ToInt32 (fileBytes, 28);
            //UInt16 blockAlign = BitConverter.ToUInt16 (fileBytes, 32);
            UInt16 bitDepth = BitConverter.ToUInt16 (fileBytes, 34);
    
            int headerOffset = 16 + 4 + subchunk1 + 4;
            int subchunk2 = BitConverter.ToInt32 (fileBytes, headerOffset);
            //Debug.LogFormat ("riff={0} wave={1} subchunk1={2} format={3} channels={4} sampleRate={5} byteRate={6} blockAlign={7} bitDepth={8} headerOffset={9} subchunk2={10} filesize={11}", riff, wave, subchunk1, formatCode, channels, sampleRate, byteRate, blockAlign, bitDepth, headerOffset, subchunk2, fileBytes.Length);
    
            float[] data;
            switch (bitDepth) {
            case 8:
                data = Convert8BitByteArrayToAudioClipData (fileBytes, headerOffset, subchunk2);
                break;
            case 16:
                data = Convert16BitByteArrayToAudioClipData (fileBytes, headerOffset, subchunk2);
                break;
            case 24:
                data = Convert24BitByteArrayToAudioClipData (fileBytes, headerOffset, subchunk2);
                break;
            case 32:
                data = Convert32BitByteArrayToAudioClipData (fileBytes, headerOffset, subchunk2);
                break;
            default:
                throw new Exception (bitDepth + " bit depth is not supported.");
            }
    
            AudioClip audioClip = AudioClip.Create (name, data.Length, (int)channels, sampleRate, false);
            audioClip.SetData (data, 0);
            return audioClip;
        }
    
        #region wav file bytes to Unity AudioClip conversion methods
    
        private static float[] Convert8BitByteArrayToAudioClipData (byte[] source, int headerOffset, int dataSize)
        {
            int wavSize = BitConverter.ToInt32 (source, headerOffset);
            headerOffset += sizeof(int);
            Debug.AssertFormat (wavSize > 0 && wavSize == dataSize, "Failed to get valid 8-bit wav size: {0} from data bytes: {1} at offset: {2}", wavSize, dataSize, headerOffset);
    
            float[] data = new float[wavSize];
    
            sbyte maxValue = sbyte.MaxValue;
    
            int i = 0;
            while (i < wavSize) {
                data [i] = (float)source [i] / maxValue;
                ++i;
            }
    
            return data;
        }
    
        private static float[] Convert16BitByteArrayToAudioClipData (byte[] source, int headerOffset, int dataSize)
        {
            int wavSize = BitConverter.ToInt32 (source, headerOffset);
            headerOffset += sizeof(int);
            Debug.AssertFormat (wavSize > 0 && wavSize == dataSize, "Failed to get valid 16-bit wav size: {0} from data bytes: {1} at offset: {2}", wavSize, dataSize, headerOffset);
    
            int x = sizeof(Int16); // block size = 2
            int convertedSize = wavSize / x;
    
            float[] data = new float[convertedSize];
    
            Int16 maxValue = Int16.MaxValue;
    
            int offset = 0;
            int i = 0;
            while (i < convertedSize) {
                offset = i * x + headerOffset;
                data [i] = (float)BitConverter.ToInt16 (source, offset) / maxValue;
                ++i;
            }
    
            Debug.AssertFormat (data.Length == convertedSize, "AudioClip .wav data is wrong size: {0} == {1}", data.Length, convertedSize);
    
            return data;
        }
    
        private static float[] Convert24BitByteArrayToAudioClipData (byte[] source, int headerOffset, int dataSize)
        {
            int wavSize = BitConverter.ToInt32 (source, headerOffset);
            headerOffset += sizeof(int);
            Debug.AssertFormat (wavSize > 0 && wavSize == dataSize, "Failed to get valid 24-bit wav size: {0} from data bytes: {1} at offset: {2}", wavSize, dataSize, headerOffset);
    
            int x = 3; // block size = 3
            int convertedSize = wavSize / x;
    
            int maxValue = Int32.MaxValue;
    
            float[] data = new float[convertedSize];
    
            byte[] block = new byte[sizeof(int)]; // using a 4 byte block for copying 3 bytes, then copy bytes with 1 offset
    
            int offset = 0;
            int i = 0;
            while (i < convertedSize) {
                offset = i * x + headerOffset;
                Buffer.BlockCopy (source, offset, block, 1, x);
                data [i] = (float)BitConverter.ToInt32 (block, 0) / maxValue;
                ++i;
            }
    
            Debug.AssertFormat (data.Length == convertedSize, "AudioClip .wav data is wrong size: {0} == {1}", data.Length, convertedSize);
    
            return data;
        }
    
        private static float[] Convert32BitByteArrayToAudioClipData (byte[] source, int headerOffset, int dataSize)
        {
            int wavSize = BitConverter.ToInt32 (source, headerOffset);
            headerOffset += sizeof(int);
            Debug.AssertFormat (wavSize > 0 && wavSize == dataSize, "Failed to get valid 32-bit wav size: {0} from data bytes: {1} at offset: {2}", wavSize, dataSize, headerOffset);
    
            int x = sizeof(float); // block size = 4
            int convertedSize = wavSize / x;
    
            Int32 maxValue = Int32.MaxValue;
    
            float[] data = new float[convertedSize];
    
            int offset = 0;
            int i = 0;
            while (i < convertedSize) {
                offset = i * x + headerOffset;
                data [i] = (float)BitConverter.ToInt32 (source, offset) / maxValue;
                ++i;
            }
    
            Debug.AssertFormat (data.Length == convertedSize, "AudioClip .wav data is wrong size: {0} == {1}", data.Length, convertedSize);
    
            return data;
        }
    
        #endregion
    
        public static byte[] FromAudioClip (AudioClip audioClip)
        {
            string file;
            return FromAudioClip (audioClip, out file, false);
        }
    
        public static byte[] FromAudioClip (AudioClip audioClip, out string filepath, bool saveAsFile = true, string dirname = "recordings")
        {
            MemoryStream stream = new MemoryStream ();
    
            const int headerSize = 44;
    
            // get bit depth
            UInt16 bitDepth = 16; //BitDepth (audioClip);
    
            // NB: Only supports 16 bit
            //Debug.AssertFormat (bitDepth == 16, "Only converting 16 bit is currently supported. The audio clip data is {0} bit.", bitDepth);
    
            // total file size = 44 bytes for header format and audioClip.samples * factor due to float to Int16 / sbyte conversion
            int fileSize = audioClip.samples * BlockSize_16Bit + headerSize; // BlockSize (bitDepth)
    
            // chunk descriptor (riff)
            WriteFileHeader (ref stream, fileSize);
            // file header (fmt)
            WriteFileFormat (ref stream, audioClip.channels, audioClip.frequency, bitDepth);
            // data chunks (data)
            WriteFileData (ref stream, audioClip, bitDepth);
    
            byte[] bytes = stream.ToArray ();
    
            // Validate total bytes
            Debug.AssertFormat (bytes.Length == fileSize, "Unexpected AudioClip to wav format byte count: {0} == {1}", bytes.Length, fileSize);
    
            // Save file to persistant storage location
            if (saveAsFile) {
                filepath = string.Format ("{0}/{1}/{2}.{3}", Application.streamingAssetsPath, dirname, DateTime.UtcNow.ToString ("yyMMdd-HHmmss-fff"), "wav");
                Directory.CreateDirectory (Path.GetDirectoryName (filepath));
                File.WriteAllBytes (filepath, bytes);
                Debug.Log ("Auto-saved .wav file: " + filepath);
            } else {
                filepath = null;
            }
    
            stream.Dispose ();
    
            return bytes;
        }
    
        #region write .wav file functions
    
        private static int WriteFileHeader (ref MemoryStream stream, int fileSize)
        {
            int count = 0;
            int total = 12;
    
            // riff chunk id
            byte[] riff = Encoding.ASCII.GetBytes ("RIFF");
            count += WriteBytesToMemoryStream (ref stream, riff, "ID");
    
            // riff chunk size
            int chunkSize = fileSize - 8; // total size - 8 for the other two fields in the header
            count += WriteBytesToMemoryStream (ref stream, BitConverter.GetBytes (chunkSize), "CHUNK_SIZE");
    
            byte[] wave = Encoding.ASCII.GetBytes ("WAVE");
            count += WriteBytesToMemoryStream (ref stream, wave, "FORMAT");
    
            // Validate header
            Debug.AssertFormat (count == total, "Unexpected wav descriptor byte count: {0} == {1}", count, total);
    
            return count;
        }
    
        private static int WriteFileFormat (ref MemoryStream stream, int channels, int sampleRate, UInt16 bitDepth)
        {
            int count = 0;
            int total = 24;
    
            byte[] id = Encoding.ASCII.GetBytes ("fmt ");
            count += WriteBytesToMemoryStream (ref stream, id, "FMT_ID");
    
            int subchunk1Size = 16; // 24 - 8
            count += WriteBytesToMemoryStream (ref stream, BitConverter.GetBytes (subchunk1Size), "SUBCHUNK_SIZE");
    
            UInt16 audioFormat = 1;
            count += WriteBytesToMemoryStream (ref stream, BitConverter.GetBytes (audioFormat), "AUDIO_FORMAT");
    
            UInt16 numChannels = Convert.ToUInt16 (channels);
            count += WriteBytesToMemoryStream (ref stream, BitConverter.GetBytes (numChannels), "CHANNELS");
    
            count += WriteBytesToMemoryStream (ref stream, BitConverter.GetBytes (sampleRate), "SAMPLE_RATE");
    
            int byteRate = sampleRate * channels * BytesPerSample (bitDepth);
            count += WriteBytesToMemoryStream (ref stream, BitConverter.GetBytes (byteRate), "BYTE_RATE");
    
            UInt16 blockAlign = Convert.ToUInt16 (channels * BytesPerSample (bitDepth));
            count += WriteBytesToMemoryStream (ref stream, BitConverter.GetBytes (blockAlign), "BLOCK_ALIGN");
    
            count += WriteBytesToMemoryStream (ref stream, BitConverter.GetBytes (bitDepth), "BITS_PER_SAMPLE");
    
            // Validate format
            Debug.AssertFormat (count == total, "Unexpected wav fmt byte count: {0} == {1}", count, total);
    
            return count;
        }
    
        private static int WriteFileData (ref MemoryStream stream, AudioClip audioClip, UInt16 bitDepth)
        {
            int count = 0;
            int total = 8;
    
            // Copy float[] data from AudioClip
            float[] data = new float[audioClip.samples * audioClip.channels];
            audioClip.GetData (data, 0);
    
            byte[] bytes = ConvertAudioClipDataToInt16ByteArray (data);
    
            byte[] id = Encoding.ASCII.GetBytes ("data");
            count += WriteBytesToMemoryStream (ref stream, id, "DATA_ID");
    
            int subchunk2Size = Convert.ToInt32 (audioClip.samples * BlockSize_16Bit); // BlockSize (bitDepth)
            count += WriteBytesToMemoryStream (ref stream, BitConverter.GetBytes (subchunk2Size), "SAMPLES");
    
            // Validate header
            Debug.AssertFormat (count == total, "Unexpected wav data id byte count: {0} == {1}", count, total);
    
            // Write bytes to stream
            count += WriteBytesToMemoryStream (ref stream, bytes, "DATA");
    
            // Validate audio data
            Debug.AssertFormat (bytes.Length == subchunk2Size, "Unexpected AudioClip to wav subchunk2 size: {0} == {1}", bytes.Length, subchunk2Size);
    
            return count;
        }
    
        private static byte[] ConvertAudioClipDataToInt16ByteArray (float[] data)
        {
            MemoryStream dataStream = new MemoryStream ();
    
            int x = sizeof(Int16);
    
            Int16 maxValue = Int16.MaxValue;
    
            int i = 0;
            while (i < data.Length) {
                dataStream.Write (BitConverter.GetBytes (Convert.ToInt16 (data [i] * maxValue)), 0, x);
                ++i;
            }
            byte[] bytes = dataStream.ToArray ();
    
            // Validate converted bytes
            Debug.AssertFormat (data.Length * x == bytes.Length, "Unexpected float[] to Int16 to byte[] size: {0} == {1}", data.Length * x, bytes.Length);
    
            dataStream.Dispose ();
    
            return bytes;
        }
    
        private static int WriteBytesToMemoryStream (ref MemoryStream stream, byte[] bytes, string tag = "")
        {
            int count = bytes.Length;
            stream.Write (bytes, 0, count);
            //Debug.LogFormat ("WAV:{0} wrote {1} bytes.", tag, count);
            return count;
        }
    
        #endregion
    
        /// <summary>
        /// Calculates the bit depth of an AudioClip
        /// </summary>
        /// <returns>The bit depth. Should be 8 or 16 or 32 bit.</returns>
        /// <param name="audioClip">Audio clip.</param>
        public static UInt16 BitDepth (AudioClip audioClip)
        {
            UInt16 bitDepth = Convert.ToUInt16 (audioClip.samples * audioClip.channels * audioClip.length / audioClip.frequency);
            Debug.AssertFormat (bitDepth == 8 || bitDepth == 16 || bitDepth == 32, "Unexpected AudioClip bit depth: {0}. Expected 8 or 16 or 32 bit.", bitDepth);
            return bitDepth;
        }
    
        private static int BytesPerSample (UInt16 bitDepth)
        {
            return bitDepth / 8;
        }
    
        private static int BlockSize (UInt16 bitDepth)
        {
            switch (bitDepth) {
            case 32:
                return sizeof(Int32); // 32-bit -> 4 bytes (Int32)
            case 16:
                return sizeof(Int16); // 16-bit -> 2 bytes (Int16)
            case 8:
                return sizeof(sbyte); // 8-bit -> 1 byte (sbyte)
            default:
                throw new Exception (bitDepth + " bit depth is not supported.");
            }
        }
    
        private static string FormatCode (UInt16 code)
        {
            switch (code) {
            case 1:
                return "PCM";
            case 2:
                return "ADPCM";
            case 3:
                return "IEEE";
            case 7:
                return "μ-law";
            case 65534:
                return "WaveFormatExtensable";
            default:
                Debug.LogWarning ("Unknown wav code format:" + code);
                return "";
            }
        }
    
    }

使用

//保存录音
                string outPath;
                WavUtility.FromAudioClip(audioClip,out outPath, true);

[https_github.com_deadlyfingers_UnityWav]: https://github.com/deadlyfingers/UnityWav