Use low-power VAAPI H264 encoding

Author: tces1

internal/transcode/ffmpeg_args_test.go

@@ -228,6 +228,29 @@ func TestBuildFFmpegArgsDoesNotForceVAAPIH264Profile(t *testing.T) {
 	}
 }
 
+func TestBuildFFmpegArgsUsesVAAPILowPowerEncoding(t *testing.T) {
+	session := &Session{
+		ID:  "item123",
+		Dir: t.TempDir(),
+	}
+	request := Request{InputURL: "http://upstream/stream"}
+
+	for _, pipeline := range []string{"vaapi-full", "vaapi-encode"} {
+		t.Run(pipeline, func(t *testing.T) {
+			args := buildFFmpegArgs(session, request, FFmpegOptions{
+				HardwareDecode:   "vaapi",
+				HardwareDevice:   "/dev/dri/renderD128",
+				HardwarePipeline: pipeline,
+			})
+
+			lowPowerIndex := slices.Index(args, "-low_power")
+			if lowPowerIndex < 0 || args[lowPowerIndex+1] != "1" {
+				t.Fatalf("VAAPI pipeline should request low-power encoding: %v", args)
+			}
+		})
+	}
+}
+
 func TestBuildFFmpegArgsCapsVideoOutputTo1080p(t *testing.T) {
 	session := &Session{
 		ID:  "item123",

internal/transcode/manager.go

@@ -1249,6 +1249,7 @@ func appendVideoTranscodeArgs(args []string, options FFmpegOptions) []string {
 	case "vaapi-full":
 		return append(args,
 			"-c:v", "h264_vaapi",
+			"-low_power", "1",
 			"-g", strconv.Itoa(lowLatencyGOP),
 			"-keyint_min", strconv.Itoa(lowLatencyGOP),
 			"-bf", "0",
@@ -1258,6 +1259,7 @@ func appendVideoTranscodeArgs(args []string, options FFmpegOptions) []string {
 		return append(args,
 			"-vf", softwareScaleFilter(maxTranscodeWidth, maxTranscodeHeight)+",format=nv12,hwupload",
 			"-c:v", "h264_vaapi",
+			"-low_power", "1",
 			"-level", "4.1",
 			"-g", strconv.Itoa(lowLatencyGOP),
 			"-keyint_min", strconv.Itoa(lowLatencyGOP),