2019-09-24 17:10:21

by Sandy Huang

Subject: Re: [PATCH 01/36] drm/fourcc: Add 2 plane YCbCr 10bit format support

在 2019/9/23 上午5:53, Ville Syrjälä 写道:
> On Mon, Sep 23, 2019 at 08:38:50PM +0800, Sandy Huang wrote:
>> diff --git a/include/uapi/drm/drm_fourcc.h b/include/uapi/drm/drm_fourcc.h
>> index 3feeaa3..5fe89e9 100644
>> --- a/include/uapi/drm/drm_fourcc.h
>> +++ b/include/uapi/drm/drm_fourcc.h
>> @@ -266,6 +266,21 @@ extern "C" {
>> #define DRM_FORMAT_P016 fourcc_code('P', '0', '1', '6') /* 2x2 subsampled Cr:Cb plane 16 bits per channel */
>>
>> /*
>> + * 2 plane YCbCr 10bit
>> + * index 0 = Y plane, [9:0] Y
>> + * index 1 = Cr:Cb plane, [19:0] Cr:Cb little endian
>> + * or
>> + * index 1 = Cb:Cr plane, [19:0] Cb:Cr little endian
> What does "little endian" even mean for these?

It's Inherited from the following define, the difference is 8bit and 10bit.

/*
 * 2 plane YCbCr
 * index 0 = Y plane, [7:0] Y
 * index 1 = Cr:Cb plane, [15:0] Cr:Cb little endian
 * or
 * index 1 = Cb:Cr plane, [15:0] Cb:Cr little endian
 */
#define DRM_FORMAT_NV12        fourcc_code('N', 'V', '1', '2') /* 2x2
subsampled Cr:Cb plane */
#define DRM_FORMAT_NV21        fourcc_code('N', 'V', '2', '1') /* 2x2
subsampled Cb:Cr plane */
#define DRM_FORMAT_NV16        fourcc_code('N', 'V', '1', '6') /* 2x1
subsampled Cr:Cb plane */
#define DRM_FORMAT_NV61        fourcc_code('N', 'V', '6', '1') /* 2x1
subsampled Cb:Cr plane */
#define DRM_FORMAT_NV24        fourcc_code('N', 'V', '2', '4') /*
non-subsampled Cr:Cb plane */
#define DRM_FORMAT_NV42        fourcc_code('N', 'V', '4',


>
>> + */
>> +
>> +#define DRM_FORMAT_NV12_10 fourcc_code('N', 'A', '1', '2') /* 2x2 subsampled Cr:Cb plane */
>> +#define DRM_FORMAT_NV21_10 fourcc_code('N', 'A', '2', '1') /* 2x2 subsampled Cb:Cr plane */
>> +#define DRM_FORMAT_NV16_10 fourcc_code('N', 'A', '1', '6') /* 2x1 subsampled Cr:Cb plane */
>> +#define DRM_FORMAT_NV61_10 fourcc_code('N', 'A', '6', '1') /* 2x1 subsampled Cb:Cr plane */
>> +#define DRM_FORMAT_NV24_10 fourcc_code('N', 'A', '2', '4') /* non-subsampled Cr:Cb plane */
>> +#define DRM_FORMAT_NV42_10 fourcc_code('N', 'A', '4', '2') /* non-subsampled Cb:Cr plane */
>> +
>> +/*
>> * 3 plane YCbCr
>> * index 0: Y plane, [7:0] Y
>> * index 1: Cb plane, [7:0] Cb
>> --
>> 2.7.4
>>
>>
>>
>> _______________________________________________
>> dri-devel mailing list
>> [email protected]
>> https://lists.freedesktop.org/mailman/listinfo/dri-devel

2019-09-25 21:43:55

by Ville Syrjälä

Subject: Re: [PATCH 01/36] drm/fourcc: Add 2 plane YCbCr 10bit format support

On Mon, Sep 23, 2019 at 06:05:22AM -0700, sandy.huang wrote:
>
> 在 2019/9/23 上午5:53, Ville Syrjälä 写道:
> > On Mon, Sep 23, 2019 at 08:38:50PM +0800, Sandy Huang wrote:
> >> diff --git a/include/uapi/drm/drm_fourcc.h b/include/uapi/drm/drm_fourcc.h
> >> index 3feeaa3..5fe89e9 100644
> >> --- a/include/uapi/drm/drm_fourcc.h
> >> +++ b/include/uapi/drm/drm_fourcc.h
> >> @@ -266,6 +266,21 @@ extern "C" {
> >> #define DRM_FORMAT_P016 fourcc_code('P', '0', '1', '6') /* 2x2 subsampled Cr:Cb plane 16 bits per channel */
> >>
> >> /*
> >> + * 2 plane YCbCr 10bit
> >> + * index 0 = Y plane, [9:0] Y
> >> + * index 1 = Cr:Cb plane, [19:0] Cr:Cb little endian
> >> + * or
> >> + * index 1 = Cb:Cr plane, [19:0] Cb:Cr little endian
> > What does "little endian" even mean for these?
>
> It's Inherited from the following define, the difference is 8bit and 10bit.
> /*
>  * 2 plane YCbCr
>  * index 0 = Y plane, [7:0] Y
>  * index 1 = Cr:Cb plane, [15:0] Cr:Cb little endian
>  * or
>  * index 1 = Cb:Cr plane, [15:0] Cb:Cr little endian
>  */
> #define DRM_FORMAT_NV12        fourcc_code('N', 'V', '1', '2') /* 2x2
> subsampled Cr:Cb plane */
> #define DRM_FORMAT_NV21        fourcc_code('N', 'V', '2', '1') /* 2x2
> subsampled Cb:Cr plane */
> #define DRM_FORMAT_NV16        fourcc_code('N', 'V', '1', '6') /* 2x1
> subsampled Cr:Cb plane */
> #define DRM_FORMAT_NV61        fourcc_code('N', 'V', '6', '1') /* 2x1
> subsampled Cb:Cr plane */
> #define DRM_FORMAT_NV24        fourcc_code('N', 'V', '2', '4') /*
> non-subsampled Cr:Cb plane */
> #define DRM_FORMAT_NV42        fourcc_code('N', 'V', '4',

Something not aligned to bytes can't have its endianness defined the
same way as these. Just doesn't make sense.

>
>
>
> >
> >> + */
> >> +
> >> +#define DRM_FORMAT_NV12_10 fourcc_code('N', 'A', '1', '2') /* 2x2 subsampled Cr:Cb plane */
> >> +#define DRM_FORMAT_NV21_10 fourcc_code('N', 'A', '2', '1') /* 2x2 subsampled Cb:Cr plane */
> >> +#define DRM_FORMAT_NV16_10 fourcc_code('N', 'A', '1', '6') /* 2x1 subsampled Cr:Cb plane */
> >> +#define DRM_FORMAT_NV61_10 fourcc_code('N', 'A', '6', '1') /* 2x1 subsampled Cb:Cr plane */
> >> +#define DRM_FORMAT_NV24_10 fourcc_code('N', 'A', '2', '4') /* non-subsampled Cr:Cb plane */
> >> +#define DRM_FORMAT_NV42_10 fourcc_code('N', 'A', '4', '2') /* non-subsampled Cb:Cr plane */
> >> +
> >> +/*
> >> * 3 plane YCbCr
> >> * index 0: Y plane, [7:0] Y
> >> * index 1: Cb plane, [7:0] Cb
> >> --
> >> 2.7.4
> >>
> >>
> >>
> >> _______________________________________________
> >> dri-devel mailing list
> >> [email protected]
> >> https://lists.freedesktop.org/mailman/listinfo/dri-devel
>

--
Ville Syrjälä
Intel

2019-09-26 07:39:00

by Sandy Huang

Subject: Re: [PATCH 01/36] drm/fourcc: Add 2 plane YCbCr 10bit format support

在 2019/9/24 上午2:30, Ville Syrjälä 写道:
> On Mon, Sep 23, 2019 at 06:05:22AM -0700, sandy.huang wrote:
>> 在 2019/9/23 上午5:53, Ville Syrjälä 写道:
>>> On Mon, Sep 23, 2019 at 08:38:50PM +0800, Sandy Huang wrote:
>>>> diff --git a/include/uapi/drm/drm_fourcc.h b/include/uapi/drm/drm_fourcc.h
>>>> index 3feeaa3..5fe89e9 100644
>>>> --- a/include/uapi/drm/drm_fourcc.h
>>>> +++ b/include/uapi/drm/drm_fourcc.h
>>>> @@ -266,6 +266,21 @@ extern "C" {
>>>> #define DRM_FORMAT_P016 fourcc_code('P', '0', '1', '6') /* 2x2 subsampled Cr:Cb plane 16 bits per channel */
>>>>
>>>> /*
>>>> + * 2 plane YCbCr 10bit
>>>> + * index 0 = Y plane, [9:0] Y
>>>> + * index 1 = Cr:Cb plane, [19:0] Cr:Cb little endian
>>>> + * or
>>>> + * index 1 = Cb:Cr plane, [19:0] Cb:Cr little endian
>>> What does "little endian" even mean for these?
>> It's Inherited from the following define, the difference is 8bit and 10bit.
>> /*
>>  * 2 plane YCbCr
>>  * index 0 = Y plane, [7:0] Y
>>  * index 1 = Cr:Cb plane, [15:0] Cr:Cb little endian
>>  * or
>>  * index 1 = Cb:Cr plane, [15:0] Cb:Cr little endian
>>  */
>> #define DRM_FORMAT_NV12        fourcc_code('N', 'V', '1', '2') /* 2x2
>> subsampled Cr:Cb plane */
>> #define DRM_FORMAT_NV21        fourcc_code('N', 'V', '2', '1') /* 2x2
>> subsampled Cb:Cr plane */
>> #define DRM_FORMAT_NV16        fourcc_code('N', 'V', '1', '6') /* 2x1
>> subsampled Cr:Cb plane */
>> #define DRM_FORMAT_NV61        fourcc_code('N', 'V', '6', '1') /* 2x1
>> subsampled Cb:Cr plane */
>> #define DRM_FORMAT_NV24        fourcc_code('N', 'V', '2', '4') /*
>> non-subsampled Cr:Cb plane */
>> #define DRM_FORMAT_NV42        fourcc_code('N', 'V', '4',
> Something not aligned to bytes can't have its endianness defined the
> same way as these. Just doesn't make sense.


Get it ,thanks.

>>
>>
>>>> + */
>>>> +
>>>> +#define DRM_FORMAT_NV12_10 fourcc_code('N', 'A', '1', '2') /* 2x2 subsampled Cr:Cb plane */
>>>> +#define DRM_FORMAT_NV21_10 fourcc_code('N', 'A', '2', '1') /* 2x2 subsampled Cb:Cr plane */
>>>> +#define DRM_FORMAT_NV16_10 fourcc_code('N', 'A', '1', '6') /* 2x1 subsampled Cr:Cb plane */
>>>> +#define DRM_FORMAT_NV61_10 fourcc_code('N', 'A', '6', '1') /* 2x1 subsampled Cb:Cr plane */
>>>> +#define DRM_FORMAT_NV24_10 fourcc_code('N', 'A', '2', '4') /* non-subsampled Cr:Cb plane */
>>>> +#define DRM_FORMAT_NV42_10 fourcc_code('N', 'A', '4', '2') /* non-subsampled Cb:Cr plane */
>>>> +
>>>> +/*
>>>> * 3 plane YCbCr
>>>> * index 0: Y plane, [7:0] Y
>>>> * index 1: Cb plane, [7:0] Cb
>>>> --
>>>> 2.7.4
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> dri-devel mailing list
>>>> [email protected]
>>>> https://lists.freedesktop.org/mailman/listinfo/dri-devel