IMX6 bayer to RGB

prasadadireddy — Wed, 20 Mar 2019 14:31:13 GMT

Hi,

We are using Aptina sensor (mt9p031) and interfaced with csi parallel bus. My sensor output gives bayer RGB (GRGB format) height & width = 2580X1944. I am able to display monochrome image with 15 fps.

Using opencv I am able to convert bayer to RGB, but it's not meeting our requirement (i.e., FPS is too low). I know IMX6 doesn't have ISP, so I planned to implement demosaicing algoritim at driver level.

Please suggest is it possible to implement at driver level, if yes please share the required modifications..

Re: IMX6 bayer to RGB

Bio_TICFSL — Wed, 03 Apr 2019 15:12:59 GMT

Hi prasad,

.MX6 IPU don't make Bayer conversion. You will need to use some graphics library/API like gstreamer, ffmpeg and others to make this conversion using the CPU. IPU (IC, DP, DC and etc) doesn't recognize bayer as a valid image format. It can receive bayer format from CSI port as generic data.

I have this capture driver (using the IPU) and used the following code to map the DMA memory (from IPU) to user space: Normally because of DMA memory is mapped uncached, but due to size and usage, it's no problem to map it cached.

/* function to map DMA memory to user space */

static int capture_mmap(struct file *file, struct vm_area_struct *vm)

{

struct capture_device *dev = file->private_data;

size_t rsize = vm->vm_end - vm->vm_start;

int map;

int idx;

if ((vm->vm_pgoff * PAGE_SIZE) != (unsigned long)dev->dma)

return -ENOMEM; /* wrong base address */

if (down_interruptible(&dev->busy_lock))

return -EINTR;

vm->vm_page_prot = phys_mem_access_prot(file, vm->vm_pgoff, rsize, vm->vm_page_prot);

/* map DMA memory to user process (allow cacheable, since data much larger than cache) */

if (remap_pfn_range(vm, vm->vm_start, vm->vm_pgoff, rsize, vm->vm_page_prot))

map = EAGAIN;

else

map = 0;

up(&dev->busy_lock);

return map;

}

If you use some driver from NXP, you may have to change the driver.

Regards

i.MX ProcessorsのトピックIMX6 bayer to RGB

IMX6 bayer to RGB

Re: IMX6 bayer to RGB