FFmpeg：在Windows上使用AMD GPU编码x264？

Question

我目前正在录制的视频在我的联想笔记本电脑凭借其内置在使用的FFmpeg的Windows 10.我的目标之一是使CPU使用率尽可能低的摄像头，这就是为什么我要推的H264编码到GPU。 现在，我的笔记本电脑变得有点棘手。因为它使用两个GPU。第一款GPU是Intel HD 5500图形单元作为CPU的一部分。这个最喜欢用于非要求苛刻的应用程序，如办公室等，以节省能源。另一款是AMD R5 M330，将用于游戏等图形密集型应用。

目前，我使用下面的命令来编码网络摄像头流英特尔HD GPU：

ffmpeg -f dshow -vcodec mjpeg -video_size 1280x720 -framerate 30 video="Lenovo EasyCamera":audio="Mikrofon (Realtek High Definition Audio)" -c:v h264_qsv -g 60 -q 28 -look_ahead 0 -preset:v faster -c:a aac -q:a 0.6 -r 30 output.mp4 

这并不工作，但迄今为止似乎这款GPU没有足够的动力能够以跟上更高比特率的帧速率或大量的i帧。视频开始缺乏并跳过帧。如果我使用CPU编码，一切都很顺利。

现在，我的笔记本电脑得到了第二AMD GPU有很多更多的权力这将是一个很好的尝试在一个编码，但我无法找到有关如何在AMD硬件编码在Windows 10的任何信息，所以，我的问题是：ffmpeg命令如何使用AMD硬件进行h264编码？

Answer 1

当前的ffmpeg的版本现在支持各大厂商的GPU硬件编码。下面是该h264_amf（H.264）和hevc_amf（H.265或HEVC）编码器，你将与AMD独立显卡使用，从ffmpeg -h full采取的选项：

h264_amf AVOptions: 
    -usage    <int>  E..V.... Encoder Usage (from 0 to 3) (default transcoding) 
    transcoding     E..V.... Generic Transcoding 
    ultralowlatency    E..V.... 
    lowlatency     E..V.... 
    webcam      E..V.... Webcam 
    -profile   <int>  E..V.... Profile (from 66 to 257) (default main) 
    main       E..V.... 
    high       E..V.... 
    constrained_baseline    E..V.... 
    constrained_high    E..V.... 
    -level    <int>  E..V.... Profile Level (from 0 to 62) (default auto) 
    auto       E..V.... 
    1.0       E..V.... 
    1.1       E..V.... 
    1.2       E..V.... 
    1.3       E..V.... 
    2.0       E..V.... 
    2.1       E..V.... 
    2.2       E..V.... 
    3.0       E..V.... 
    3.1       E..V.... 
    3.2       E..V.... 
    4.0       E..V.... 
    4.1       E..V.... 
    4.2       E..V.... 
    5.0       E..V.... 
    5.1       E..V.... 
    5.2       E..V.... 
    6.0       E..V.... 
    6.1       E..V.... 
    6.2       E..V.... 
    -quality   <int>  E..V.... Quality Preference (from 0 to 2) (default speed) 
    speed      E..V.... Prefer Speed 
    balanced      E..V.... Balanced 
    quality      E..V.... Prefer Quality 
    -rc    <int>  E..V.... Rate Control Method (from -1 to 3) (default -1) 
    cqp       E..V.... Constant Quantization Parameter 
    cbr       E..V.... Constant Bitrate 
    vbr_peak      E..V.... Peak Contrained Variable Bitrate 
    vbr_latency     E..V.... Latency Constrained Variable Bitrate 
    -enforce_hrd  <boolean> E..V.... Enforce HRD (default false) 
    -filler_data  <boolean> E..V.... Filler Data Enable (default false) 
    -vbaq    <boolean> E..V.... Enable VBAQ (default false) 
    -frame_skipping <boolean> E..V.... Rate Control Based Frame Skip (default false) 
    -qp_i    <int>  E..V.... Quantization Parameter for I-Frame (from -1 to 51) (default -1) 
    -qp_p    <int>  E..V.... Quantization Parameter for P-Frame (from -1 to 51) (default -1) 
    -qp_b    <int>  E..V.... Quantization Parameter for B-Frame (from -1 to 51) (default -1) 
    -preanalysis  <boolean> E..V.... Pre-Analysis Mode (default false) 
    -max_au_size  <int>  E..V.... Maximum Access Unit Size for rate control (in bits) (from 0 to INT_MAX) (default 0) 
    -header_spacing <int>  E..V.... Header Insertion Spacing (from -1 to 1000) (default -1) 
    -bf_delta_qp  <int>  E..V.... B-Picture Delta QP (from -10 to 10) (default 4) 
    -bf_ref   <boolean> E..V.... Enable Reference to B-Frames (default true) 
    -bf_ref_delta_qp <int>  E..V.... Reference B-Picture Delta QP (from -10 to 10) (default 4) 
    -intra_refresh_mb <int>  E..V.... Intra Refresh MBs Number Per Slot in Macroblocks (from 0 to INT_MAX) (default 0) 
    -coder    <int>  E..V.... Coding Type (from 0 to 2) (default auto) 
    auto       E..V.... Automatic 
    cavlc      E..V.... Context Adaptive Variable-Length Coding 
    cabac      E..V.... Context Adaptive Binary Arithmetic Coding 
    -me_half_pel  <boolean> E..V.... Enable ME Half Pixel (default true) 
    -me_quarter_pel <boolean> E..V.... Enable ME Quarter Pixel (default true) 
    -aud    <boolean> E..V.... Inserts AU Delimiter NAL unit (default false) 
    -log_to_dbg  <boolean> E..V.... Enable AMF logging to debug output (default false) 

hevc_amf AVOptions: 
    -usage    <int>  E..V.... Set the encoding usage (from 0 to 3) (default transcoding) 
    transcoding     E..V.... 
    ultralowlatency    E..V.... 
    lowlatency     E..V.... 
    webcam      E..V.... 
    -profile   <int>  E..V.... Set the profile (default main) (from 1 to 1) (default main) 
    main       E..V.... 
    -profile_tier  <int>  E..V.... Set the profile tier (default main) (from 0 to 1) (default main) 
    main       E..V.... 
    high       E..V.... 
    -level    <int>  E..V.... Set the encoding level (default auto) (from 0 to 186) (default auto) 
    auto       E..V.... 
    1.0       E..V.... 
    2.0       E..V.... 
    2.1       E..V.... 
    3.0       E..V.... 
    3.1       E..V.... 
    4.0       E..V.... 
    4.1       E..V.... 
    5.0       E..V.... 
    5.1       E..V.... 
    5.2       E..V.... 
    6.0       E..V.... 
    6.1       E..V.... 
    6.2       E..V.... 
    -quality   <int>  E..V.... Set the encoding quality (from 0 to 10) (default speed) 
    balanced      E..V.... 
    speed      E..V.... 
    quality      E..V.... 
    -rc    <int>  E..V.... Set the rate control mode (from -1 to 3) (default -1) 
    cqp       E..V.... Constant Quantization Parameter 
    cbr       E..V.... Constant Bitrate 
    vbr_peak      E..V.... Peak Contrained Variable Bitrate 
    vbr_latency     E..V.... Latency Constrained Variable Bitrate 
    -header_insertion_mode <int>  E..V.... Set header insertion mode (from 0 to 2) (default none) 
    none       E..V.... 
    gop       E..V.... 
    idr       E..V.... 
    -gops_per_idr  <int>  E..V.... GOPs per IDR 0-no IDR will be inserted (from 0 to INT_MAX) (default 60) 
    -preanalysis  <boolean> E..V.... Enable preanalysis (default false) 
    -vbaq    <boolean> E..V.... Enable VBAQ (default false) 
    -enforce_hrd  <boolean> E..V.... Enforce HRD (default false) 
    -filler_data  <boolean> E..V.... Filler Data Enable (default false) 
    -max_au_size  <int>  E..V.... Maximum Access Unit Size for rate control (in bits) (from 0 to INT_MAX) (default 0) 
    -min_qp_i   <int>  E..V.... min quantization parameter for I-frame (from -1 to 51) (default -1) 
    -max_qp_i   <int>  E..V.... max quantization parameter for I-frame (from -1 to 51) (default -1) 
    -min_qp_p   <int>  E..V.... min quantization parameter for P-frame (from -1 to 51) (default -1) 
    -max_qp_p   <int>  E..V.... max quantization parameter for P-frame (from -1 to 51) (default -1) 
    -qp_p    <int>  E..V.... quantization parameter for P-frame (from -1 to 51) (default -1) 
    -qp_i    <int>  E..V.... quantization parameter for I-frame (from -1 to 51) (default -1) 
    -skip_frame  <boolean> E..V.... Rate Control Based Frame Skip (default false) 
    -me_half_pel  <boolean> E..V.... Enable ME Half Pixel (default true) 
    -me_quarter_pel <boolean> E..V.... Enable ME Quarter Pixel (default true) 
    -aud    <boolean> E..V.... Inserts AU Delimiter NAL unit (default false) 
    -log_to_dbg  <boolean> E..V.... Enable AMF logging to debug output (default false) 

例如，ffmpeg -i input.mkv -c:v hevc_amf -rc cqp -qp_p 0 -qp_i 0 -c:a copy output.mkv将是无损的。请注意，虽然速度更快，但文件大小会比使用libx264或libx265时的文件大小大得多 - 而这正是硬件编码器目前的状况。您可能需要使用硬件编码器来记录速度，然后使用libx264或libx265等软件编码器来减小文件大小。