public FilterContext AddSource(AudioFormatInfo format)
{
AVFilterContext *filterContext;
var sampleFormatName = ffmpeg.av_get_sample_fmt_name(format.SampleFormat.ToAVFormat());
var channelLayoutHex = ((ulong)format.ChannelLayout);
var hexChannelLayout = ((long)format.ChannelLayout).ToString("x");
var args = string.Join(':',
$"time_base=1/{format.SampleRate}",
$"sample_rate={format.SampleRate}",
$"sample_fmt={sampleFormatName}",
$"channel_layout=0x{hexChannelLayout}"
);
ffmpeg.avfilter_graph_create_filter(
filt_ctx: &filterContext,
filt: Filter.FromName("abuffer").Pointer,
name: "in",
args: args,
opaque: null,
graph_ctx: pointer
).EnsureSuccess();
// Console.WriteLine("added source:" + Marshal.PtrToStringAnsi((IntPtr)filterContext->name));
return(new FilterContext(filterContext));
}
public AudioFrame(AudioFormatInfo format, int sampleCount)
{
this.format = format ?? throw new ArgumentNullException(nameof(format));
Memory = Buffer.Allocate(AudioFormatHelper.GetBufferSize(format, sampleCount));
channelPlanePointers = ffmpeg.av_calloc((ulong)IntPtr.Size, 8);
ffmpeg.av_samples_fill_arrays(
audio_data: (byte **)channelPlanePointers,
linesize: null,
buf: (byte *)Memory.Pointer,
nb_channels: format.ChannelCount,
sample_fmt: format.SampleFormat.ToAVFormat(),
nb_samples: sampleCount,
align: 0
);
// Set the frame properties
SampleFormat = format.SampleFormat;
SampleRate = format.SampleRate;
SampleCount = sampleCount;
ChannelCount = format.ChannelCount;
ChannelLayout = format.ChannelLayout;
pointer->extended_data = (byte **)channelPlanePointers;
}
public unsafe static int GetBufferSize(this AudioFormatInfo format, int sampleCount)
{
if (sampleCount <= 0)
{
throw new ArgumentException("Must be > 0");
}
return(ffmpeg.av_samples_get_buffer_size(
linesize: null,
nb_channels: format.ChannelCount,
nb_samples: sampleCount,
sample_fmt: format.SampleFormat.ToAVFormat(),
align: 0
));
}
