多年来，我在ffmpeg的MFX和OneVPL集成方面的经验表明，使用混合策略在多个支持QSV的平台上取得了一致的成功。
在这里，我们初始化VAAPI的HWContext，然后通过hwmap导出用于编码的qsv设备/示例，而不是直接调用QSV的HWContext。使用hwmap还允许在Map模式方面有更大的运行时灵活性，可以选择通过directMap模式请求零拷贝仿真。
请参阅下面的解决方案，它改编自上面的命令行：

ffmpeg -init_hw_device vaapi=intel:/dev/dri/renderD128 \
-hwaccel vaapi -hwaccel_output_format vaapi \
-hwaccel_device intel -filter_hw_device intel \
-i test_video.mp4 \
-vf 'scale_vaapi,hwmap=derive_device=qsv,format=qsv' \
-c:v hevc_qsv -f mp4 output.mp4

您可以通过以下方式查看相应的编解码器 Package 器选项：

ffmpeg -h encoder=hevc_qsv

输出示例：

Encoder hevc_qsv [HEVC (Intel Quick Sync Video acceleration)]:
    General capabilities: delay hybrid 
    Threading capabilities: none
    Supported hardware devices: qsv qsv qsv 
    Supported pixel formats: nv12 p010le p012le yuyv422 y210le qsv bgra x2rgb10le vuyx xv30le
hevc_qsv encoder AVOptions:
  -async_depth       <int>        E..V....... Maximum processing parallelism (from 1 to INT_MAX) (default 4)
  -preset            <int>        E..V....... (from 0 to 7) (default 0)
     veryfast        7            E..V.......
     faster          6            E..V.......
     fast            5            E..V.......
     medium          4            E..V.......
     slow            3            E..V.......
     slower          2            E..V.......
     veryslow        1            E..V.......
  -forced_idr        <boolean>    E..V....... Forcing I frames as IDR frames (default false)
  -low_power         <boolean>    E..V....... enable low power mode(experimental: many limitations by mfx version, BRC modes, etc.) (default auto)
  -rdo               <int>        E..V....... Enable rate distortion optimization (from -1 to 1) (default -1)
  -max_frame_size    <int>        E..V....... Maximum encoded frame size in bytes (from -1 to INT_MAX) (default -1)
  -max_frame_size_i  <int>        E..V....... Maximum encoded I frame size in bytes (from -1 to INT_MAX) (default -1)
  -max_frame_size_p  <int>        E..V....... Maximum encoded P frame size in bytes (from -1 to INT_MAX) (default -1)
  -max_slice_size    <int>        E..V....... Maximum encoded slice size in bytes (from -1 to INT_MAX) (default -1)
  -mbbrc             <int>        E..V....... MB level bitrate control (from -1 to 1) (default -1)
  -extbrc            <int>        E..V....... Extended bitrate control (from -1 to 1) (default -1)
  -p_strategy        <int>        E..V....... Enable P-pyramid: 0-default 1-simple 2-pyramid(bf need to be set to 0). (from 0 to 2) (default 0)
  -b_strategy        <int>        E..V....... Strategy to choose between I/P/B-frames (from -1 to 1) (default -1)
  -dblk_idc          <int>        E..V....... This option disable deblocking. It has value in range 0~2. (from 0 to 2) (default 0)
  -low_delay_brc     <boolean>    E..V....... Allow to strictly obey avg frame size (default auto)
  -max_qp_i          <int>        E..V....... Maximum video quantizer scale for I frame (from -1 to 51) (default -1)
  -min_qp_i          <int>        E..V....... Minimum video quantizer scale for I frame (from -1 to 51) (default -1)
  -max_qp_p          <int>        E..V....... Maximum video quantizer scale for P frame (from -1 to 51) (default -1)
  -min_qp_p          <int>        E..V....... Minimum video quantizer scale for P frame (from -1 to 51) (default -1)
  -max_qp_b          <int>        E..V....... Maximum video quantizer scale for B frame (from -1 to 51) (default -1)
  -min_qp_b          <int>        E..V....... Minimum video quantizer scale for B frame (from -1 to 51) (default -1)
  -adaptive_i        <int>        E..V....... Adaptive I-frame placement (from -1 to 1) (default -1)
  -adaptive_b        <int>        E..V....... Adaptive B-frame placement (from -1 to 1) (default -1)
  -scenario          <int>        E..V....... A hint to encoder about the scenario for the encoding session (from 0 to 8) (default unknown)
     unknown         0            E..V.......
     displayremoting 1            E..V.......
     videoconference 2            E..V.......
     archive         3            E..V.......
     livestreaming   4            E..V.......
     cameracapture   5            E..V.......
     videosurveillance 6            E..V.......
     gamestreaming   7            E..V.......
     remotegaming    8            E..V.......
  -avbr_accuracy     <int>        E..V....... Accuracy of the AVBR ratecontrol (unit of tenth of percent) (from 0 to 65535) (default 0)
  -avbr_convergence  <int>        E..V....... Convergence of the AVBR ratecontrol (unit of 100 frames) (from 0 to 65535) (default 0)
  -skip_frame        <int>        E..V....... Allow frame skipping (from 0 to 3) (default no_skip)
     no_skip         0            E..V....... Frame skipping is disabled
     insert_dummy    1            E..V....... Encoder inserts into bitstream frame where all macroblocks are encoded as skipped
     insert_nothing  2            E..V....... Encoder inserts nothing into bitstream
     brc_only        3            E..V....... skip_frame metadata indicates the number of missed frames before the current frame
  -idr_interval      <int>        E..V....... Distance (in I-frames) between IDR frames (from -1 to INT_MAX) (default 0)
     begin_only      -1           E..V....... Output an IDR-frame only at the beginning of the stream
  -load_plugin       <int>        E..V....... A user plugin to load in an internal session (from 0 to 2) (default hevc_hw)
     none            0            E..V.......
     hevc_sw         1            E..V.......
     hevc_hw         2            E..V.......
  -load_plugins      <string>     E..V....... A :-separate list of hexadecimal plugin UIDs to load in an internal session (default "")
  -look_ahead_depth  <int>        E..V....... Depth of look ahead in number frames, available when extbrc option is enabled (from 0 to 100) (default 0)
  -profile           <int>        E..V....... (from 0 to INT_MAX) (default unknown)
     unknown         0            E..V.......
     main            1            E..V.......
     main10          2            E..V.......
     mainsp          3            E..V.......
     rext            4            E..V.......
     scc             9            E..V.......
  -tier              <int>        E..V....... Set the encoding tier (only level >= 4 can support high tier) (from 0 to 256) (default high)
     main            0            E..V.......
     high            256          E..V.......
  -gpb               <boolean>    E..V....... 1: GPB (generalized P/B frame); 0: regular P frame (default true)
  -tile_cols         <int>        E..V....... Number of columns for tiled encoding (from 0 to 65535) (default 0)
  -tile_rows         <int>        E..V....... Number of rows for tiled encoding (from 0 to 65535) (default 0)
  -recovery_point_sei <int>        E..V....... Insert recovery point SEI messages (from -1 to 1) (default -1)
  -aud               <boolean>    E..V....... Insert the Access Unit Delimiter NAL (default false)
  -pic_timing_sei    <boolean>    E..V....... Insert picture timing SEI with pic_struct_syntax element (default true)
  -transform_skip    <int>        E..V....... Turn this option ON to enable transformskip (from -1 to 1) (default -1)
  -int_ref_type      <int>        E..V....... Intra refresh type. B frames should be set to 0 (from -1 to 65535) (default -1)
     none            0            E..V.......
     vertical        1            E..V.......
     horizontal      2            E..V.......
     slice           3            E..V.......
  -int_ref_cycle_size <int>        E..V....... Number of frames in the intra refresh cycle (from -1 to 65535) (default -1)
  -int_ref_qp_delta  <int>        E..V....... QP difference for the refresh MBs (from -32768 to 32767) (default -32768)
  -int_ref_cycle_dist <int>        E..V....... Distance between the beginnings of the intra-refresh cycles in frames (from -1 to 32767) (default -1)

对于使用的过滤器：

ffmpeg -h filter=scale_vaapi

输出示例：

Filter scale_vaapi
  Scale to/from VAAPI surfaces.
    Inputs:
       #0: default (video)
    Outputs:
       #0: default (video)
scale_vaapi AVOptions:
   w                 <string>     ..FV....... Output video width (default "iw")
   h                 <string>     ..FV....... Output video height (default "ih")
   format            <string>     ..FV....... Output video format (software format of hardware frames)
   mode              <int>        ..FV....... Scaling mode (from 0 to 768) (default hq)
     default         0            ..FV....... Use the default (depend on the driver) scaling algorithm
     fast            256          ..FV....... Use fast scaling algorithm
     hq              512          ..FV....... Use high quality scaling algorithm
     nl_anamorphic   768          ..FV....... Use nolinear anamorphic scaling algorithm
   out_color_matrix  <string>     ..FV....... Output colour matrix coefficient set
   out_range         <int>        ..FV....... Output colour range (from 0 to 2) (default 0)
     full            2            ..FV....... Full range
     limited         1            ..FV....... Limited range
     jpeg            2            ..FV....... Full range
     mpeg            1            ..FV....... Limited range
     tv              1            ..FV....... Limited range
     pc              2            ..FV....... Full range
   out_color_primaries <string>     ..FV....... Output colour primaries
   out_color_transfer <string>     ..FV....... Output colour transfer characteristics
   out_chroma_location <string>     ..FV....... Output chroma sample location
   force_original_aspect_ratio <int>        ..FV....... decrease or increase w/h if necessary to keep the original AR (from 0 to 2) (default disable)
     disable         0            ..FV.......
     decrease        1            ..FV.......
     increase        2            ..FV.......
   force_divisible_by <int>        ..FV....... enforce that the output resolution is divisible by a defined integer when force_original_aspect_ratio is used (from 1 to 256) (default 1)

ffmpeg -h filter=hwmap

输出示例：

Filter hwmap
  Map hardware frames
    Inputs:
       #0: default (video)
    Outputs:
       #0: default (video)
hwmap AVOptions:
   mode              <flags>      ..FV....... Frame mapping mode (default read+write)
     read                         ..FV....... Mapping should be readable
     write                        ..FV....... Mapping should be writeable
     overwrite                    ..FV....... Mapping will always overwrite the entire frame
     direct                       ..FV....... Mapping should not involve any copying
   derive_device     <string>     ..FV....... Derive a new device of this type
   reverse           <int>        ..FV....... Map in reverse (create and allocate in the sink) (from 0 to 1) (default 0)

额外备注：

并非所有的速率控制和编码模式都可以在您的平台上使用。要验证所支持的内容，请使用intel-media-driver项目上托管的支持矩阵交叉验证vainfo的输出。
英特尔在Github上的媒体交付项目还提供了reference command-lines，概述了在低功耗编码、速率控制方法可用性等方面的性能和质量权衡的具体修复。这是一个很好的开始，可以掌握生产中可能出现的问题的基本知识。
在可能的情况下，尝试构建由英特尔维护的cartwheel-ffmpeg分支，用于排除与QSV相关的性能问题，同样，您可能会遇到的report any bugs。