FFMPEG的强大无需多说，举几个用到的功能，直接贴代码了
还有更多命令用到时搜索即可
视频转码
public static string DecodeMp4ToFlv(string mp4, string format = ".flv", int timeout = )
{
var args = "-y -i {0} -vcodec copy {1}".Formatting("\"{0}\"".Formatting(mp4), "\"{0}\"".Formatting(strFlvPath));
string output, error;
if (timeout <= )
timeout = **; // 超时时间 = 5 分钟
ProcessHelper.Process(strFFMPEGPath, args, timeout, out output, out error);
if (!error.IsNullOrEmpty())
{
Logger.Error("{0}{1} : {2}{0}".Formatting(Environment.NewLine, "FFmpeg", error));
} return flv;
}
视频合并
public static string ConcatMp4(string mp41, string mp42)
{ var args = " -i \"concat:" + mp41 + "|" + mp42 + "|\" -c copy -bsf:a aac_adtstoasc -movflags +faststart " + outputpath;
string output, error; int timeout = * * ; // 超时时间 = 2 分钟
ProcessHelper.Process(strFFMPEGPath, args, timeout, out output, out error);
if (!error.IsNullOrEmpty())
{
Logger.Error("{0}{1} : {2}{0}".Formatting(Environment.NewLine, "FFmpeg", error));
} return outputpath;
}
获取视频时长
private static int GetVideoDuration(string ffmpegfile, string sourceFile)
{
try
{
using (System.Diagnostics.Process ffmpeg = new System.Diagnostics.Process())
{
String duration; // soon will hold our video's duration in the form "HH:MM:SS.UU"
String result; // temp variable holding a string representation of our video's duration
StreamReader errorreader; // StringWriter to hold output from ffmpeg // we want to execute the process without opening a shell
ffmpeg.StartInfo.UseShellExecute = false;
//ffmpeg.StartInfo.ErrorDialog = false;
ffmpeg.StartInfo.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
// redirect StandardError so we can parse it
// for some reason the output comes through over StandardError
ffmpeg.StartInfo.RedirectStandardError = true;
// set the file name of our process, including the full path
// (as well as quotes, as if you were calling it from the command-line)
ffmpeg.StartInfo.FileName = ffmpegfile; // set the command-line arguments of our process, including full paths of any files
// (as well as quotes, as if you were passing these arguments on the command-line)
ffmpeg.StartInfo.Arguments = "-i " + sourceFile; // start the process
ffmpeg.Start(); // now that the process is started, we can redirect output to the StreamReader we defined
errorreader = ffmpeg.StandardError; // wait until ffmpeg comes back
ffmpeg.WaitForExit(); // read the output from ffmpeg, which for some reason is found in Process.StandardError
result = errorreader.ReadToEnd(); // a little convoluded, this string manipulation...
// working from the inside out, it:
// takes a substring of result, starting from the end of the "Duration: " label contained within,
// (execute "ffmpeg.exe -i somevideofile" on the command-line to verify for yourself that it is there)
// and going the full length of the timestamp duration = result.Substring(result.IndexOf("Duration: ") + ("Duration: ").Length, ("00:00:00").Length); string[] ss = duration.Split(':');
int h = int.Parse(ss[]);
int m = int.Parse(ss[]);
int s = int.Parse(ss[]);
return h * + m * + s;
}
}
catch (System.Exception ex)
{
return ;
}
}
Process处理类如下，也可以自己写个
public static void Process(string startFile, string args, int timeout, out string standardOutput,
out string standardError)
{
using (var process = new ProcessExecutor(startFile, args, timeout))
{
process.Execute(out standardOutput, out standardError);
}
}
internal class ProcessExecutor : IDisposable
{
private readonly StringBuilder error;
private readonly AutoResetEvent errorWaitHandle;
private readonly StringBuilder output;
private readonly int timeout;
private AutoResetEvent outputWaitHandle;
private Process process; public ProcessExecutor(string startFile, string args, int timeout = )
{
process = new Process();
//设置进程启动信息属性StartInfo，这是ProcessStartInfo类
process.StartInfo.FileName = Encoding.UTF8.GetString(Encoding.UTF8.GetBytes(startFile));
process.StartInfo.Arguments = Encoding.UTF8.GetString(Encoding.UTF8.GetBytes(args)); process.StartInfo.UseShellExecute = false;
//提供的标准输出流只有2k,超过大小会卡住;如果有大量输出,就读出来
process.StartInfo.RedirectStandardOutput = true;
process.StartInfo.RedirectStandardError = true;
process.StartInfo.CreateNoWindow = true; output = new StringBuilder();
error = new StringBuilder(); outputWaitHandle = new AutoResetEvent(false);
errorWaitHandle = new AutoResetEvent(false); this.timeout = timeout; RegisterToEvents();
} public void Dispose()
{
UnregisterFromEvents(); if (process != null)
{
process.Dispose();
process = null;
}
if (errorWaitHandle != null)
{
errorWaitHandle.Close();
outputWaitHandle = null;
}
if (outputWaitHandle != null)
{
outputWaitHandle.Close();
outputWaitHandle = null;
}
} public void Execute(out string standardOutput, out string standardError)
{
process.Start(); process.BeginOutputReadLine();
process.BeginErrorReadLine(); if (process.WaitForExit(timeout) &&
outputWaitHandle.WaitOne(timeout) &&
errorWaitHandle.WaitOne(timeout))
{ }
else
{
// if timeout then kill the procee
process.Kill();
} standardOutput = output.ToString();
standardError = error.ToString();
} private void RegisterToEvents()
{
process.OutputDataReceived += process_OutputDataReceived;
process.ErrorDataReceived += process_ErrorDataReceived;
} private void UnregisterFromEvents()
{
process.OutputDataReceived -= process_OutputDataReceived;
process.ErrorDataReceived -= process_ErrorDataReceived;
} private void process_ErrorDataReceived(object sender, DataReceivedEventArgs e)
{
if (e.Data == null)
{
errorWaitHandle.Set();
}
else
{
error.AppendLine(e.Data);
}
} private void process_OutputDataReceived(object sender, DataReceivedEventArgs e)
{
if (e.Data == null)
{
outputWaitHandle.Set();
}
else
{
output.AppendLine(e.Data);
}
}
}