I have some doubt regarding Linux kernel V4l2 API's. When capture application calls Reqbuff ioctl to allocate n no of buffer which would belongs to v4l2 layer and display application calls the Reqbuff ioctl to allocate N no of buffer which would also belongs to device memory. Question: 1. V4l2 maintains the generic layer for all devices in which buffers can be allocated by any device and can be handle by any device? 2. If not then while capturing the data from capture device can capture device allocated buffer gets filled and while displaying the same data there memory copy happens between capture buffer and output buffers? 3. If not then I want to capture data from capture device and display onto display device through the v4l2 framework layer. Awaiting for responce! Thanks in advance Kaushal