Is the buffer corresponding to the bufferdesc parameter CPU buffer or DMA buffer

[Fiona.Chen]

@1967367916

(1)Is hardware buffer and DMA buffer the same concept from your description？
（2）If the bufferDesc param is a dma fd,can I access it with low-level functions?,Please have a look at Some questions about NvJPEGDecoder::decodeToFd.
I use same interface to access the dma fd from two cases,I get different width and height param.case 1 param is not aligned, but case 2 param is aligned.Why are the obtained parameters different?
(3)What is the meaning of the parameter layout？，what’t the differnce between the ‘NVBUF_LAYOUT_PITCH’ and ‘NVBUF_LAYOUT_BLOCK_LINEAR’?

1. No. For the Jetson device, the memType value shows the hardware buffer type. NVBUF_MEM_DEFAULT, NVBUF_MEM_SURFACE_ARRAY and NVBUF_MEM_HANDLE are different types of hardware buffers. I think NVBUF_MEM_HANDLE type is what you call DMA buffer.
2. NvBuffer and NvBufsurface are totally different.
3. You can refer to What's the difference between LAYOUT_PITCH and LAYOUT_BLOCKLINEAR?