Re: [PATCH v5 2/4] staging: media: Introduce NVIDIA Tegra video decoder driver

[Dmitry Osipenko]

22.11.2020 04:02, Ezequiel Garcia пишет:
> Hi Dmitry,
> 
...
>> +++ b/drivers/staging/media/tegra-vde/TODO
>> @@ -0,0 +1,4 @@
>> +TODO:
>> +       - Implement V4L2 API once it gains support for stateless decoders.
>> +
>> +Contact: Dmitry Osipenko <digetx@xxxxxxxxx>
> 
> The API for H264 stateless decoding is ready.
> See https://lkml.org/lkml/2020/11/18/795.

Hello Ezequiel,

Thank you for the notification! My last attempt at implementing V4L API
support was about a year ago and it stopped once I realized that there
is no userspace which uses that API. FFMPEG and chromium browser had
some kind of V4L support, but it all was oriented at downstream driver
stacks, and thus, not usable. Do you know what is the current status?

> One minor comment below.
> 
...
>> +       // PPS
>> +       __u8  pic_init_qp;
>> +       __u8  deblocking_filter_control_present_flag;
>> +       __u8  constrained_intra_pred_flag;
>> +       __u8  chroma_qp_index_offset;
>> +       __u8  pic_order_present_flag;
>> +
> 
> This seems to be bottom_field_pic_order_in_frame_present_flag,
> as there is no "pic_order_present_flag" syntax element.

Correct, looks like I borrowed that name from the libvdpau API.

https://vdpau.pages.freedesktop.org/libvdpau/struct_vdp_picture_info_h264.html#a405f7ef26ea76bb2c446e151062fc001