[Mesa-dev] [PATCH v2 6/7] egl/android: Add support for YV12 pixel format (v2)

[Chad Versace]

On 08/08/2016 01:58 PM, Rob Herring wrote:
> On Mon, Aug 8, 2016 at 1:39 PM, Chad Versace <chad at kiwitree.net> wrote:
>> On 08/02/2016 04:07 AM, Tomasz Figa wrote:
>>>
>>> This patch adds support for YV12 pixel format to the Android platform
>>> backend. Only creating EGL images is supported, it is not added to the
>>> list of available visuals.
>>>
>>> v2: Use const array defined just for YV12 instead of trying to be overly
>>>     generic.
>>>
>>> Signed-off-by: Tomasz Figa <tfiga at chromium.org>
>>> Signed-off-by: Kalyan Kondapally <kalyan.kondapally at intel.com>
>>> ---
>>>  src/egl/drivers/dri2/platform_android.c | 56
>>> +++++++++++++++++++++++++++++----
>>>  1 file changed, 50 insertions(+), 6 deletions(-)
>>
>>
>>
>>
>>> @@ -512,22 +518,60 @@ static _EGLImage *
>>>  droid_create_image_from_prime_fd(_EGLDisplay *disp, _EGLContext *ctx,
>>>                                   struct ANativeWindowBuffer *buf, int fd)
>>>  {
>>> +   unsigned int offsets[3] = { 0, 0, 0 };
>>> +   unsigned int pitches[3] = { 0, 0, 0 };
>>> +
>>>     const int fourcc = get_fourcc(buf->format);
>>> -   const int pitch = buf->stride * get_format_bpp(buf->format);
>>> +   if (fourcc == -1) {
>>> +      _eglError(EGL_BAD_PARAMETER, "eglCreateEGLImageKHR");
>>> +      return NULL;
>>> +   }
>>>
>>> -   const EGLint attr_list[14] = {
>>> +   pitches[0] = buf->stride * get_format_bpp(buf->format);
>>> +   if (pitches[0] == 0) {
>>> +      _eglError(EGL_BAD_PARAMETER, "eglCreateEGLImageKHR");
>>> +      return NULL;
>>> +   }
>>> +
>>> +   switch (buf->format) {
>>> +   case HAL_PIXEL_FORMAT_YV12:
>>> +      /* Y plane is assumed to be at offset 0. */
>>> +      /* Cr plane is located after Y plane */
>>> +      offsets[1] = offsets[0] + pitches[0] * buf->height;
>>> +      pitches[1] = ALIGN(pitches[0] / 2, 16);
>>> +      /* Cb plane is located after Cr plane */
>>> +      offsets[2] = offsets[1] + pitches[1] * buf->height / 2;
>>
>>
>> I believe the above should be
>>    offsets[2] = offsets[1] + pitches[1] * ALIGN(buf->height, 2) / 2;
>> to accommodate buffers with odd height.
>
> Android defines this format is even height and width with a stride
> multiple of 16 pixels:
>
>     /*
>      * Android YUV format:
>      *
>      * This format is exposed outside of the HAL to software decoders and
>      * applications.  EGLImageKHR must support it in conjunction with the
>      * OES_EGL_image_external extension.
>      *
>      * YV12 is a 4:2:0 YCrCb planar format comprised of a WxH Y plane followed
>      * by (W/2) x (H/2) Cr and Cb planes.
>      *
>      * This format assumes
>      * - an even width
>      * - an even height
>      * - a horizontal stride multiple of 16 pixels
>      * - a vertical stride equal to the height
>      *
>      *   y_size = stride * height
>      *   c_stride = ALIGN(stride/2, 16)
>      *   c_size = c_stride * height/2
>      *   size = y_size + c_size * 2
>      *   cr_offset = y_size
>      *   cb_offset = y_size + c_size
>      *
>      * When used with ANativeWindow, the dataSpace field describes the color
>      * space of the buffer.
>      */

Thanks for clarifying.

Reviewed-by: Chad Versace <chad at kiwitree.net>

And pushed to master.