allow preprocessing to keep stereo; asks which files to use

src/render/ffmpeg.rs

@@ -157,7 +157,9 @@ enum FfmpegFilter {
 		filters: Vec<Filter>,
 		output: Cow<'static, str>
 	},
-	Loudnorm,
+	Loudnorm {
+		stereo: bool
+	},
 	Rescale(Resolution)
 }
 
@@ -216,10 +218,14 @@ impl Ffmpeg {
 		self
 	}
 
-	pub fn enable_loudnorm(&mut self) -> &mut Self {
+	pub fn enable_loudnorm(&mut self, loudnorm_stereo: bool) -> &mut Self {
 		match &mut self.filter {
-			FfmpegFilter::None => self.filter = FfmpegFilter::Loudnorm,
-			FfmpegFilter::Loudnorm => {},
+			FfmpegFilter::None => {
+				self.filter = FfmpegFilter::Loudnorm {
+					stereo: loudnorm_stereo
+				}
+			},
+			FfmpegFilter::Loudnorm { stereo } if *stereo == loudnorm_stereo => {},
 			_ => panic!("An incompatible type of filter has been set before")
 		}
 		self
@@ -228,7 +234,6 @@ impl Ffmpeg {
 	pub fn rescale_video(&mut self, res: Resolution) -> &mut Self {
 		match &mut self.filter {
 			FfmpegFilter::None => self.filter = FfmpegFilter::Rescale(res),
-			FfmpegFilter::Loudnorm => {},
 			_ => panic!("An incompatible type of filter has been set before")
 		}
 		self
@@ -243,7 +248,7 @@ impl Ffmpeg {
 		let (vdec, venc, aenc) = match &self.filter {
 			FfmpegFilter::None => (false, false, false),
 			FfmpegFilter::Filters { .. } => (false, true, true),
-			FfmpegFilter::Loudnorm => (false, false, true),
+			FfmpegFilter::Loudnorm { .. } => (false, false, true),
 			FfmpegFilter::Rescale(_) => (true, true, false)
 		};
 
@@ -286,7 +291,7 @@ impl Ffmpeg {
 				cmd.arg("-map").arg("[v]");
 				cmd.arg("-map").arg(channel('a', &output));
 			},
-			FfmpegFilter::Loudnorm => {
+			FfmpegFilter::Loudnorm { stereo: false } => {
 				cmd.arg("-af").arg(concat!(
 					"pan=mono|c0=FR,",
 					"loudnorm=dual_mono=true:print_format=summary,",
@@ -294,6 +299,10 @@ impl Ffmpeg {
 					"aformat=sample_rates=48000"
 				));
 			},
+			FfmpegFilter::Loudnorm { stereo: true } => {
+				cmd.arg("-af")
+					.arg("loudnorm=print_format=summary,aformat=sample_rates=48000");
+			},
 			FfmpegFilter::Rescale(res) => {
 				cmd.arg("-vf").arg(if vaapi {
 					format!("scale_vaapi=w={}:h={}", res.width(), res.height())

src/render/mod.rs

@@ -211,7 +211,7 @@ impl<'a> Renderer<'a> {
 			concat: true,
 			..FfmpegInput::new(recording_txt)
 		});
-		ffmpeg.enable_loudnorm();
+		ffmpeg.enable_loudnorm(project.source.stereo);
 		ffmpeg.run()?;
 
 		let width = ffprobe_video("stream=width", &recording_mkv)?.parse()?;