Add nvenc-av1 video mode.

Author: lisamelton

README.md

@@ -132,8 +132,14 @@ The `svt_av1_10bit` encoder can produce output compatible with the HDR10 and HDR
 
 When using this mode, audio output is in Opus format at slightly lower bitrates. Why Opus? Because it's higher quality than AAC and if you can play AV1 format video then you can certainly play Opus format audio.
 
+### `--mode nvenc-av1`
+
+This mode uses the `nvenc_av1_10bit` Nvidia hardware-based encoder, also with a constant quality ratecontrol system. The output is actually about the same size as that from the software-based `svt_av1_10bit` encoder in `av1` mode, but this is MUCH faster.
+
+Be aware that, like other Nvidia encoders, `nvenc_h265_10bit` can only produce HDR10-compatible output. And like the `av1` mode, audio output is in Opus format at slightly lower bitrates.
+
 > [!NOTE]
-> *Additional `--mode` arguments leveraging the `vt_h265_10bit` and `nvenc_av1_10bit` video encoders, likely to be named `vt-hevc` and `nvenc-av1`, are under consideration pending ratecontrol tuning. And tuning of any `vt-hevc` mode implementation will be delayed until I actually have an Apple Silicon Mac. But I'm working on the `nvenc-av1` mode implementation now since I already have the necessary Nvidia hardware.*
+> *An additional `--mode` argument leveraging the `vt_h265_10bit` video encoder, likely to be named `vt-hevc`, is under consideration pending ratecontrol tuning which will be delayed until I actually have an Apple Silicon Mac.*
 
 ## Calling `HandBrakeCLI` from `transcode-video.rb`
 

transcode-video.rb

@@ -36,15 +36,16 @@ def usage
 Options:
     --debug           increase diagnostic information
 -n, --dry-run         don't transcode, just show `HandBrakeCLI` command
--m, --mode h264|hevc|nvenc-hevc|av1|none
+-m, --mode h264|hevc|nvenc-hevc|av1|nvenc-av1|none
                       set video encoding mode (default: h264)
 -p, --preset NAME     apply video encoder preset (default: 8 for av1)
 -b, --bitrate TARGET  set video bitrate target (default: based on input)
 -q, --quality VALUE   set constant quality value
     --no-bframe-refs  don't use B-frames as reference frames
                         (for compatibilty with older Nvidia GPUs)
 -a, --audio-mode aac|opus|eac3|none
-                      set audio encoding mode (default: aac, opus for av1)
+                      set audio encoding mode
+                        (default: aac, opus for av1 and nvenc-av1)
     --add-audio TRACK|LANGUAGE|STRING|all
                       include audio track (default: 1)
                         (can be used multiple times)
@@ -138,11 +139,14 @@ def define_options(opts)
         @mode = case arg
         when 'h264', 'hevc', 'none'
           arg.to_sym
+        when 'nvenc-hevc'
+          :nvenc_hevc
         when 'av1'
           @audio_mode = :opus
           :av1
-        when 'nvenc-hevc'
-          :nvenc_hevc
+        when 'nvenc-av1'
+          @audio_mode = :opus
+          :nvenc_av1
         else
           fail UsageError, "unsupported video mode: #{arg}"
         end
@@ -467,6 +471,12 @@ def get_video_options(media_info)
           end
 
           preset = @preset.nil? ? '8' : [[@preset.to_i, -1].max, 13].min.to_s
+        when :nvenc_av1
+          encoder = 'nvenc_av1_10bit'
+
+          if @bitrate.nil?
+            quality = @quality.nil? ? '35' : [[@quality.to_i, 0].max, 63].min.to_s
+          end
         else
           quality = @quality
         end