Re: [PATCH v4 3/4] gpu: ipu-v3: ipu-ic: Add support for BT.709 encoding

[Steve Longerbeam <slongerbeam@gmail.com>]

On 2/12/19 3:34 AM, Philipp Zabel wrote:
> Hi Steve,
>
> On Mon, 2019-02-11 at 17:20 -0800, Steve Longerbeam wrote:
> [...]
>>> Should we support YUV BT.601 <-> YUV REC.709 conversions? That would
>>> require separate encodings for input and output.
>> How about if we pass the input and output encodings to the init ic task
>> functions, but for now require they be the same? We can support
>> transcoding in a later series.
> [...]
>> Again, I think for now, just include input/output quantization but
>> require full range for RGB and limited range for YUV.
> Yes, that is fine. I'd just like to avoid unnecessary interface changes
> between ipu-v3 and imx-media. So if we have to change it right now, why
> not plan ahead.

Agreed!

>
>> But that really balloons the arguments to ipu_ic_task_init_*(). Should
>> we create an ipu_ic_task_init structure?
> I wonder if we should just expose struct ic_csc_params

I had basically the same idea. I wasn't thinking of creating a helper to 
fill in the params but sure, I'll add that.

Steve


>   and provide a
> helper to fill it given colorspace and V4L2 encoding/quantization
> parameters. Something like:
>
> 	struct ipu_ic_csc_params csc;
>
> 	imx_media_init_ic_csc_params(&csc,
> 			in_cs, in_encoding, in_quantization,
> 			out_cs, out_encoding, out_quantization);
>
> 	ipu_ic_task_init(ic,
> 			in_width, in_height,
> 			out_width, out_height, &csc);
> 	// or
> 	ipu_ic_task_init_rsc(ic, rsc, &csc);
>
> regards
> Philipp