我正在使用这个库https://github.com/ahawker/NLibsndfile从 C# 转换带有 libSndFile 的音频文件,我做了这个方法,用于转换(将 wav 转换为 aiff):
string sourcePath = "/User/Dev/Desktop/a.wav";
string targetPath = "/User/Dev/Desktop/b.aiff";
var file = File.Create(targetPath);
file.Close();
file.Dispose();
IntPtr ptrTargetFile = file.SafeFileHandle.DangerousGetHandle();
LibsndfileInfo wavInfo = new LibsndfileInfo();
LibsndfileInfo aiffInfo = new LibsndfileInfo();
LibsndfileApi api = new LibsndfileApi();
var wavFile = api.Open(sourcePath, LibsndfileMode.Read, ref wavInfo);
var aiffFile = api.OpenFileDescriptor((int)ptrTargetFile, LibsndfileMode.Rdwr, ref aiffInfo, 0);
aiffInfo.Channels = wavInfo.Channels;
aiffInfo.SampleRate = wavInfo.SampleRate;
aiffInfo.Format = LibsndfileFormat.Aiff;
short[] buffer = new short[512];
long countOfItemsWritten = 0;
long countOfItemsReaded = 0;
while ((countOfItemsReaded=api.ReadItems(wavFile, buffer, buffer.Length))>0)
countOfItemsWritten = api.WriteItems(aiffFile, buffer, countOfItemsReaded);
api.Close(wavFile);
api.Close(aiffFile);
问题是在打开 aiff 文件的时候,该方法api.OpenFileDescriptor
总是返回一个空指针。库方法是这样的:internal static extern IntPtr sf_open_fd(int handle, LibsndfileMode mode, ref LibsndfileInfo info, int closeHandle);
知道为什么操作失败了吗?或者如何从 FileStream 中获取文件描述符处理程序?