Resize D3D11Texture2D DirectX 11 - directx

Question

I would like to resize a D3D11Texture2D to make it smaller. For example I have a texture in 1920x1080 and I would like to scale it 1280x720 for example.
Just so you know I'm not drawing at all, I just want to get the byte buffer scaled. Here is my code :
if (mRealTexture == nullptr) {
D3D11_TEXTURE2D_DESC description;
texture2D->GetDesc(&description);
description.BindFlags = 0;
description.CPUAccessFlags = D3D11_CPU_ACCESS_READ | D3D11_CPU_ACCESS_WRITE;
description.Usage = D3D11_USAGE_STAGING;
description.MiscFlags = 0;
hr = mDevice->CreateTexture2D(&description, NULL, &mRealTexture);
if (FAILED(hr)) {
if (mRealTexture) {
mRealTexture->Release();
mRealTexture = nullptr;
}
return NULL;
}
}
mImmediateContext->CopyResource(mRealTexture, texture2D);
if (mScaledTexture == nullptr) {
D3D11_TEXTURE2D_DESC description;
texture2D->GetDesc(&description);
description.CPUAccessFlags = D3D11_CPU_ACCESS_READ | D3D11_CPU_ACCESS_WRITE;
description.BindFlags = D3D11_BIND_RENDER_TARGET | D3D11_BIND_SHADER_RESOURCE;
description.Width = 1440;
description.Height = 585;
description.MipLevels = 4;
description.ArraySize = 1;
description.SampleDesc.Count = 1;
description.SampleDesc.Quality = 0;
description.Usage = D3D11_USAGE_DEFAULT;
hr = mDevice->CreateTexture2D(&description, NULL, &mScaledTexture);
if (FAILED(hr)) {
if (mScaledTexture) {
mScaledTexture->Release();
mScaledTexture = nullptr;
}
return NULL;
}
} //I want to copy the mRealTexture on the mScaledTexture, map the scaledTexture and get the buffer.
Thanks for help

Answer 1

Having thought about this and that you are left with only a couple of options.
1 - You create a viewport etc and render to your target size with a full screen quad. Which I get the feeling you don't want to do.
2 - You roll your own scaling which isn't too bad and scale texture as you copy the data from one buffer to another.
Option 2 isn't too bad, the roughest scaling would be reading a points based on the scaling ratio, but a more accurate version would be to average a number of samples based a weighted grid (the weights need to be recalculated for each pixel you visit on your target.)