On 30/06/2022 11:48, Laurent Pinchart wrote:
> On Thu, Jun 30, 2022 at 12:46:16PM +0300, Sakari Ailus wrote:
>> On Wed, Jun 29, 2022 at 03:50:47PM +0200, Hans Verkuil wrote:
>>>> @@ -585,8 +585,8 @@ static inline bool v4l2_is_hsv_enc_valid(__u8 hsv_enc)
>>>>
>>>> static inline bool v4l2_is_quant_valid(__u8 quantization)
>>>> {
>>>> - return quantization == V4L2_QUANTIZATION_FULL_RANGE ||
>>>> - quantization == V4L2_QUANTIZATION_LIM_RANGE;
>>>> + return quantization > V4L2_QUANTIZATION_DEFAULT &&
>>>> + quantization < V4L2_QUANTIZATION_LAST;
>>>
>>> There are only two quantization ranges: full and limited. And I very sincerely
>>> hope there will never be a third!
>>
>> For consistency of the checks and definitions I prefer it how it's in the
>> patch. There's no functional difference though.
>
> I'm ready to send a pull request for this patch once you and Hans agree
> on how this should be done :-) I also have a slight preference for
> consistency. Hans, what do you think ?
>
Quantization Range is quite different from the others: where the other colorimetry
settings are regularly extended with new variants, quantization range is not.
Limited vs Full range is really a reflection of two parallel developments: TV and
PC monitors. We're stuck with it, but it is highly unlikely someone will ever
introduce a third option for this.
So suggesting that it can be extended by introducing a V4L2_QUANTIZATION_LAST gives
the wrong signal IMHO.
Regards,
Hans
