public VideoFrameConverter(Size sourceSize, AVPixelFormat sourcePixelFormat, Size destinationSize, AVPixelFormat destinationPixelFormat)
{
_destinationSize = destinationSize;
_pConvertContext = ffmpeg.sws_getContext(sourceSize.Width, sourceSize.Height, sourcePixelFormat, destinationSize.Width, destinationSize.Height, destinationPixelFormat, ffmpeg.SWS_FAST_BILINEAR, null, null, null);
if (_pConvertContext == null)
{
throw new ApplicationException("Could not initialize the conversion context.");
}
var convertedFrameBufferSize = ffmpeg.av_image_get_buffer_size(destinationPixelFormat, destinationSize.Width, destinationSize.Height, 1);
_convertedFrameBufferPtr = Marshal.AllocHGlobal(convertedFrameBufferSize);
var dstData = new byte_ptrArray4();
var dstLinesize = new int_array4();
ffmpeg.av_image_fill_arrays(ref dstData, ref dstLinesize, (byte *)_convertedFrameBufferPtr, destinationPixelFormat, destinationSize.Width, destinationSize.Height, 1);
_dstLinesize = dstLinesize.ToArray();
_dstData = dstData.ToArray();
for (uint i = 0; i < 4; i++)
{
dstData[i] = null;
}
ffmpeg.av_free(&dstLinesize);
}
public static int[] GetStrides(PixelFormat pixelFormat, int width, int align)
{
// Ensure align is a power of two...
// Based on:
// https://github.com/ibukisaar/SaarFFmpeg/blob/9310b8e8dea99712c9dfec4df746cfb5b8f72d25/SaarFFmpeg/CSharp/VideoFormat.cs
// MIT Licenced
// Copyright (c) 2018 Saar Ibuki
var avFormat = pixelFormat.ToAVFormat();
int planeCount = ffmpeg.av_pix_fmt_count_planes(avFormat);
var temp = new int_array4();
ffmpeg.av_image_fill_linesizes(ref temp, avFormat, width);
var tempValues = temp.ToArray();
var strides = new int[planeCount];
for (int i = 0; i < planeCount; i++)
{
strides[i] = (tempValues[i] + (align - 1)) & ~(align - 1);
}
return(strides);
}