[FFmpeg-devel] [PATCH] lavc/qsvenc: Set default bitrate to 2M

[Timo Rothenpieler]

On 05.12.2023 09:15, Xiang, Haihao wrote:
> From: Haihao Xiang <haihao.xiang at intel.com>
> 
> 2M is suitable for more cases, e.g. 4K video.
> 
> Signed-off-by: Haihao Xiang <haihao.xiang at intel.com>
> ---
>   libavcodec/qsvenc_av1.c   | 2 +-
>   libavcodec/qsvenc_h264.c  | 2 +-
>   libavcodec/qsvenc_hevc.c  | 2 +-
>   libavcodec/qsvenc_mpeg2.c | 2 +-
>   libavcodec/qsvenc_vp9.c   | 2 +-
>   5 files changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/libavcodec/qsvenc_av1.c b/libavcodec/qsvenc_av1.c
> index c697845d7b..78c92c1844 100644
> --- a/libavcodec/qsvenc_av1.c
> +++ b/libavcodec/qsvenc_av1.c
> @@ -129,7 +129,7 @@ static const AVClass class = {
>   };
>   
>   static const FFCodecDefault qsv_enc_defaults[] = {
> -    { "b",         "1M"   },
> +    { "b",         "2M"   },

Wouldn't it be better to use a constant quality option as default, 
rather than a fixed bitrate?
2M still seems incredibly low for 1080p, let alone for 4K content.

>       { "g",         "-1"   },
>       { "bf",        "-1"   },
>       { "refs",      "0"    },
> diff --git a/libavcodec/qsvenc_h264.c b/libavcodec/qsvenc_h264.c
> index 071a9a79e9..37b39cb441 100644
> --- a/libavcodec/qsvenc_h264.c
> +++ b/libavcodec/qsvenc_h264.c
> @@ -178,7 +178,7 @@ static const AVClass class = {
>   };
>   
>   static const FFCodecDefault qsv_enc_defaults[] = {
> -    { "b",         "1M"    },
> +    { "b",         "2M"    },
>       { "refs",      "0"     },
>       { "g",         "-1"    },
>       { "bf",        "-1"    },
> diff --git a/libavcodec/qsvenc_hevc.c b/libavcodec/qsvenc_hevc.c
> index c5b7ac7cc4..181d06cb00 100644
> --- a/libavcodec/qsvenc_hevc.c
> +++ b/libavcodec/qsvenc_hevc.c
> @@ -374,7 +374,7 @@ static const AVClass class = {
>   };
>   
>   static const FFCodecDefault qsv_enc_defaults[] = {
> -    { "b",         "1M"    },
> +    { "b",         "2M"    },
>       { "refs",      "0"     },
>       { "g",         "248"   },
>       { "bf",        "-1"    },
> diff --git a/libavcodec/qsvenc_mpeg2.c b/libavcodec/qsvenc_mpeg2.c
> index 22f1ff7c0d..012cec3a58 100644
> --- a/libavcodec/qsvenc_mpeg2.c
> +++ b/libavcodec/qsvenc_mpeg2.c
> @@ -82,7 +82,7 @@ static const AVClass class = {
>   };
>   
>   static const FFCodecDefault qsv_enc_defaults[] = {
> -    { "b",         "1M"    },
> +    { "b",         "2M"    },
>       { "refs",      "0"     },
>       // same as the x264 default
>       { "g",         "250"   },
> diff --git a/libavcodec/qsvenc_vp9.c b/libavcodec/qsvenc_vp9.c
> index d0340ef94b..8658b8ec2d 100644
> --- a/libavcodec/qsvenc_vp9.c
> +++ b/libavcodec/qsvenc_vp9.c
> @@ -93,7 +93,7 @@ static const AVClass class = {
>   };
>   
>   static const FFCodecDefault qsv_enc_defaults[] = {
> -    { "b",         "1M"    },
> +    { "b",         "2M"    },
>       { "refs",      "0"     },
>       { "g",         "250"   },
>       { "trellis",   "-1"    },