ffmpeg - rgb32 数据资源映射。使用directx memcpy

Question

我一直在尝试通过谷歌搜索解决这个问题一个月。但现在我不得不在这里寻求帮助。

我想使用 ffmpeg 解码帧进行渲染。并使用帧（它转换为 RGB32 格式），我尝试用 DX2D 纹理渲染帧。

ZeroMemory(&TextureDesc, sizeof(TextureDesc));

TextureDesc.Height = pFrame->height;
TextureDesc.Width = pFrame->width;
TextureDesc.MipLevels = 1;
TextureDesc.ArraySize = 1;
TextureDesc.Format = DXGI_FORMAT_R32G32B32A32_FLOAT;            //size 16
TextureDesc.SampleDesc.Count = 1;
TextureDesc.SampleDesc.Quality = 0;
TextureDesc.Usage = D3D11_USAGE_DYNAMIC;
TextureDesc.BindFlags = D3D11_BIND_SHADER_RESOURCE;
TextureDesc.CPUAccessFlags = D3D11_CPU_ACCESS_WRITE;
TextureDesc.MiscFlags = 0;

result = m_device->CreateTexture2D(&TextureDesc, NULL, &m_2DTex);
if (FAILED(result))     return false;

ShaderResourceViewDesc.Format = TextureDesc.Format;
ShaderResourceViewDesc.ViewDimension = D3D11_SRV_DIMENSION_TEXTURE2D;
ShaderResourceViewDesc.Texture2D.MostDetailedMip = 0;
ShaderResourceViewDesc.Texture2D.MipLevels = 1;

    D3D11_MAPPED_SUBRESOURCE S_mappedResource_tt = { 0, };

ZeroMemory(&S_mappedResource_tt, sizeof(D3D11_MAPPED_SUBRESOURCE));

result = m_deviceContext->Map(m_2DTex, 0, D3D11_MAP_WRITE_DISCARD, 0, &S_mappedResource_tt);
if (FAILED(result)) return false;
BYTE* mappedData = reinterpret_cast<BYTE *>(S_mappedResource_tt.pData);
for (auto i = 0; i < pFrame->height; ++i) {
    memcpy(mappedData, pFrame->data, pFrame->linesize[0]);
    mappedData += S_mappedResource_tt.RowPitch;
    pFrame->data[0] += pFrame->linesize[0];
}

m_deviceContext->Unmap(m_2DTex, 0);

result = m_device->CreateShaderResourceView(m_2DTex, &ShaderResourceViewDesc, &m_ShaderResourceView);
if (FAILED(result))     return false;

    m_deviceContext->PSSetShaderResources(0, 1, &m_ShaderResourceView);

但它只显示黑屏（没有渲染）。我猜这是错误的 memcpy 大小。最大的问题是我不知道是什么问题。

问题 1：为贴图创建 2D 纹理有什么问题吗？

问题 2：memcpy 参数应该输入多大的参数（与格式化有关）？

我基于下面的链接。

[1] https://www.gamedev.net/forums/topic/667097-copy-2d-array-into-texture2d/ [2] https://www.gamedev.net/forums/topic/645514-directx- 11-mapping-id3d11texture2d/ [3] https://www.gamedev.net/forums/topic/606100-solved-dx11-updating-texture-data/

感谢您的观看，请回复。

标签： ffmpegmappingdirectx-11memcpytexture2d

Answer 1

没人回复。我解决了我的问题。我修改了一些代码，我不确定它是否能解决问题。黑屏原因的问题是我的矩阵。

D3D11_TEXTURE2D_DESC TextureDesc;
D3D11_RENDER_TARGET_VIEW_DESC RenderTargetViewDesc;
D3D11_SHADER_RESOURCE_VIEW_DESC ShaderResourceViewDesc;

ZeroMemory(&TextureDesc, sizeof(TextureDesc));

TextureDesc.Height = pFrame->height;
TextureDesc.Width = pFrame->width;
TextureDesc.MipLevels = 1;
TextureDesc.ArraySize = 1;
TextureDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;/*DXGI_FORMAT_R8G8B8A8_UNORM_SRGB;*/            //size 32bit
TextureDesc.SampleDesc.Count = 1;
TextureDesc.SampleDesc.Quality = 0;
TextureDesc.Usage = D3D11_USAGE_DYNAMIC;
TextureDesc.BindFlags = D3D11_BIND_SHADER_RESOURCE;
TextureDesc.CPUAccessFlags = D3D11_CPU_ACCESS_WRITE;
TextureDesc.MiscFlags = 0;

DWORD*  pInitImage = new DWORD[pFrame->width*pFrame->height];
memset(pInitImage, 0, sizeof(DWORD)*pFrame->width*pFrame->height);
D3D11_SUBRESOURCE_DATA InitData;
InitData.pSysMem = pInitImage;
InitData.SysMemPitch = pFrame->width*sizeof(DWORD);
InitData.SysMemSlicePitch = 0;
result = m_device->CreateTexture2D(&TextureDesc, &InitData, &m_2DTex);
if (FAILED(result))     return false;

ShaderResourceViewDesc.Format = TextureDesc.Format;
ShaderResourceViewDesc.ViewDimension = D3D11_SRV_DIMENSION_TEXTURE2D;
ShaderResourceViewDesc.Texture2D.MostDetailedMip = 0;
ShaderResourceViewDesc.Texture2D.MipLevels = 1;

result = m_device->CreateShaderResourceView(m_2DTex, &ShaderResourceViewDesc, &m_ShaderResourceView);
if (FAILED(result))     return false;

D3D11_MAPPED_SUBRESOURCE S_mappedResource_tt;
ZeroMemory(&S_mappedResource_tt, sizeof(S_mappedResource_tt));
DWORD   Stride = pFrame->linesize[0];

result = m_deviceContext->Map(m_2DTex, 0, D3D11_MAP_WRITE_DISCARD, 0, &S_mappedResource_tt);
if (FAILED(result)) return false;

BYTE * pFrameData = pFrame->data[0];   // now we have a pointer that points to begin of the destination buffer
BYTE* mappedData = (BYTE *)S_mappedResource_tt.pData;// +S_mappedResource_tt.RowPitch;
for (auto i = 0; i < pFrame->height; i++) {     
    memcpy(mappedData, pFrameData, Stride);
    mappedData += S_mappedResource_tt.RowPitch;
    pFrameData += Stride;
}

m_deviceContext->Unmap(m_2DTex, 0);

它工作得很好。我希望它对那些和我做同样事情的人有所帮助。