[FFmpeg-devel] [PATCH v8 01/15] avcodec/vaapi_encode: introduce a base layer for vaapi encode

[Mark Thompson]

On 18/04/2024 09:58, tong1.wu-at-intel.com at ffmpeg.org wrote:
> From: Tong Wu <tong1.wu at intel.com>
> 
> Since VAAPI and future D3D12VA implementation may share some common parameters,
> a base layer encode context is introduced as vaapi context's base.
> 
> Signed-off-by: Tong Wu <tong1.wu at intel.com>
> ---
>  libavcodec/hw_base_encode.h | 52 +++++++++++++++++++++++++++++++++++++
>  libavcodec/vaapi_encode.h   | 36 ++++---------------------
>  2 files changed, 57 insertions(+), 31 deletions(-)
>  create mode 100644 libavcodec/hw_base_encode.h
> 
> diff --git a/libavcodec/hw_base_encode.h b/libavcodec/hw_base_encode.h
> new file mode 100644
> index 0000000000..3d1974bba3
> --- /dev/null
> +++ b/libavcodec/hw_base_encode.h
> @@ -0,0 +1,52 @@
> +/*
> + * This file is part of FFmpeg.
> + *
> + * FFmpeg is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU Lesser General Public
> + * License as published by the Free Software Foundation; either
> + * version 2.1 of the License, or (at your option) any later version.
> + *
> + * FFmpeg is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> + * Lesser General Public License for more details.
> + *
> + * You should have received a copy of the GNU Lesser General Public
> + * License along with FFmpeg; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> + */
> +
> +#ifndef AVCODEC_HW_BASE_ENCODE_H
> +#define AVCODEC_HW_BASE_ENCODE_H
> +
> +#define MAX_DPB_SIZE 16
> +#define MAX_PICTURE_REFERENCES 2
> +#define MAX_REORDER_DELAY 16
> +#define MAX_ASYNC_DEPTH 64
> +#define MAX_REFERENCE_LIST_NUM 2

Is there a reason to change these from enum to defines?  I'm not seeing anywhere they should be visible to the preprocessor, and this means they are normally invisible to a debugger.

> +
> +enum {
> +    PICTURE_TYPE_IDR = 0,
> +    PICTURE_TYPE_I   = 1,
> +    PICTURE_TYPE_P   = 2,
> +    PICTURE_TYPE_B   = 3,
> +};
> +
> +enum {
> +    // Codec supports controlling the subdivision of pictures into slices.
> +    FLAG_SLICE_CONTROL         = 1 << 0,
> +    // Codec only supports constant quality (no rate control).
> +    FLAG_CONSTANT_QUALITY_ONLY = 1 << 1,
> +    // Codec is intra-only.
> +    FLAG_INTRA_ONLY            = 1 << 2,
> +    // Codec supports B-pictures.
> +    FLAG_B_PICTURES            = 1 << 3,
> +    // Codec supports referencing B-pictures.
> +    FLAG_B_PICTURE_REFERENCES  = 1 << 4,
> +    // Codec supports non-IDR key pictures (that is, key pictures do
> +    // not necessarily empty the DPB).
> +    FLAG_NON_IDR_KEY_PICTURES  = 1 << 5,
> +};
> +
> +#endif /* AVCODEC_HW_BASE_ENCODE_H */
> ...

Would it make more sense to put the HWBaseEncodeContext in this patch as well?  (With just the AVClass member.)

Thanks,

- Mark