public static byte[]? GetThumbnail(FfmpegSettings settings)
{
using var process = new Process {
StartInfo = new ProcessStartInfo {
Arguments = $" -hide_banner -loglevel panic -y {(UseCuda ? "-hwaccel cuda" : string.Empty)} -ss {settings.Position} -i \"{settings.File}\" -t 1 -f {(settings.GrayScale == 1 ? "rawvideo -pix_fmt gray" : "mjpeg")} -vframes 1 {(settings.GrayScale == 1 ? "-s 16x16" : "-vf scale=100:-1")} \"-\"",
FileName = FFmpegPath,
CreateNoWindow = true,
RedirectStandardInput = false,
RedirectStandardOutput = true,
WorkingDirectory = Path.GetDirectoryName(FFmpegPath) !,
RedirectStandardError = true,
WindowStyle = ProcessWindowStyle.Hidden
}
};
try {
process.EnableRaisingEvents = true;
process.Start();
using var ms = new MemoryStream();
process.StandardOutput.BaseStream.CopyTo(ms);
if (!process.WaitForExit(TimeoutDuration))
{
Logger.Instance.Info($"FFmpeg timed out on file '{settings.File}'");
throw new Exception();
}
return(ms.ToArray());
}
catch (Exception) {
try {
if (process.HasExited == false)
{
process.Kill();
}
}
catch { }
return(null);
}
}
public static unsafe byte[]? GetThumbnail(FfmpegSettings settings, bool extendedLogging)
{
try {
if (UseNativeBinding)
{
bool isGrayByte = settings.GrayScale == 1;
AVHWDeviceType HWDevice = HardwareAccelerationMode switch {
FFHardwareAccelerationMode.vdpau => AVHWDeviceType.AV_HWDEVICE_TYPE_VDPAU,
FFHardwareAccelerationMode.dxva2 => AVHWDeviceType.AV_HWDEVICE_TYPE_DXVA2,
FFHardwareAccelerationMode.vaapi => AVHWDeviceType.AV_HWDEVICE_TYPE_VAAPI,
FFHardwareAccelerationMode.qsv => AVHWDeviceType.AV_HWDEVICE_TYPE_QSV,
FFHardwareAccelerationMode.cuda => AVHWDeviceType.AV_HWDEVICE_TYPE_CUDA,
_ => AVHWDeviceType.AV_HWDEVICE_TYPE_NONE
};
using var vsd = new VideoStreamDecoder(settings.File, HWDevice);
if (vsd.PixelFormat < 0 || vsd.PixelFormat >= AVPixelFormat.AV_PIX_FMT_NB)
{
throw new Exception($"Invalid source pixel format");
}
Size sourceSize = vsd.FrameSize;
Size destinationSize = isGrayByte ? new Size(16, 16) : new Size(100, Convert.ToInt32(sourceSize.Height * (100 / (double)sourceSize.Width)));
AVPixelFormat destinationPixelFormat = isGrayByte ? AVPixelFormat.AV_PIX_FMT_GRAY8 : AVPixelFormat.AV_PIX_FMT_BGRA;
using var vfc =
new VideoFrameConverter(sourceSize, vsd.PixelFormat, destinationSize, destinationPixelFormat);
if (!vsd.TryDecodeFrame(out var srcFrame, settings.Position))
{
throw new Exception($"Failed decoding frame at {settings.Position}");
}
AVFrame convertedFrame = vfc.Convert(srcFrame);
if (isGrayByte)
{
int length = ffmpeg.av_image_get_buffer_size(destinationPixelFormat, convertedFrame.width,
convertedFrame.height, 1).ThrowExceptionIfError();
byte[] data = new byte[length];
Marshal.Copy((IntPtr)convertedFrame.data[0], data, 0, length);
return(data);
}
else
{
int width = convertedFrame.width;
int height = convertedFrame.height;
var totalBytes = width * height * 4;
var rgbaBytes = new byte[totalBytes];
int stride = convertedFrame.linesize[0];
if (stride == width * 4)
{
Marshal.Copy((IntPtr)convertedFrame.data[0], rgbaBytes, 0, totalBytes);
}
else
{
var sourceOffset = 0;
var destOffset = 0;
var byteWidth = width * 4;
for (var y = 0; y < height; y++)
{
Marshal.Copy((IntPtr)convertedFrame.data[0] + sourceOffset, rgbaBytes, destOffset, byteWidth);
sourceOffset += stride;
destOffset += byteWidth;
}
}
var image = Image.LoadPixelData <SixLabors.ImageSharp.PixelFormats.Bgra32>(rgbaBytes, width, height);
using MemoryStream stream = new();
image.Save(stream, new SixLabors.ImageSharp.Formats.Jpeg.JpegEncoder());
bool equal = rgbaBytes.SequenceEqual(stream.ToArray());
return(stream.ToArray());
}
}
}
catch (Exception e) {
Logger.Instance.Info($"Failed using native FFmpeg binding on '{settings.File}', try switching to process mode. Exception: {e}");
}
//https://docs.microsoft.com/en-us/dotnet/csharp/how-to/concatenate-multiple-strings#string-literals
string ffmpegArguments = $" -hide_banner -loglevel {(extendedLogging ? "error" : "quiet")}" +
$" -y -hwaccel {HardwareAccelerationMode} -ss {settings.Position} -i \"{settings.File}\"" +
$" -t 1 -f {(settings.GrayScale == 1 ? "rawvideo -pix_fmt gray" : "mjpeg")} -vframes 1" +
$" {(settings.GrayScale == 1 ? "-s 16x16" : "-vf scale=100:-1")} {CustomFFArguments} \"-\"";
using var process = new Process {
StartInfo = new ProcessStartInfo {
Arguments = ffmpegArguments,
FileName = FFmpegPath,
CreateNoWindow = true,
RedirectStandardInput = false,
RedirectStandardOutput = true,
WorkingDirectory = Path.GetDirectoryName(FFmpegPath) !,
RedirectStandardError = extendedLogging,
WindowStyle = ProcessWindowStyle.Hidden
}
};
string errOut = string.Empty;
byte[]? bytes = null;
try {
process.EnableRaisingEvents = true;
process.Start();
if (extendedLogging)
{
process.ErrorDataReceived += new DataReceivedEventHandler((sender, e) => {
if (e.Data?.Length > 0)
{
errOut += Environment.NewLine + e.Data;
}
});
process.BeginErrorReadLine();
}
using var ms = new MemoryStream();
process.StandardOutput.BaseStream.CopyTo(ms);
if (!process.WaitForExit(TimeoutDuration))
{
throw new TimeoutException($"FFmpeg timed out on file: {settings.File}");
}
else if (extendedLogging)
{
process.WaitForExit(); // Because of asynchronous event handlers, see: https://github.com/dotnet/runtime/issues/18789
}
if (process.ExitCode != 0)
{
throw new FFInvalidExitCodeException($"FFmpeg exited with: {process.ExitCode}");
}
bytes = ms.ToArray();
if (bytes.Length == 0)
{
bytes = null; // Makes subsequent checks easier
}
else if (settings.GrayScale == 1 && bytes.Length != 256)
{
bytes = null;
errOut += $"{Environment.NewLine}graybytes length != 256";
}
}
catch (Exception e) {
errOut += $"{Environment.NewLine}{e.Message}";
try {
if (process.HasExited == false)
{
process.Kill();
}
}
catch { }
bytes = null;
}
if (bytes == null || errOut.Length > 0)
{
string message = $"{((bytes == null) ? "ERROR: Failed to retrieve" : "WARNING: Problems while retrieving")} {(settings.GrayScale == 1 ? "graybytes" : "thumbnail")} from: {settings.File}";
if (extendedLogging)
{
message += $":{Environment.NewLine}{FFmpegPath} {ffmpegArguments}";
}
Logger.Instance.Info($"{message}{errOut}");
}
return(bytes);
}
