fix(mp4): match copied audio bitrate metadata

crates/coreav-cli/src/ffmpeg/encode.rs

@@ -313,6 +313,15 @@ pub fn request(
         opus,
         aac,
         aac_mp4_tail: true,
+        copied_audio_bit_rate: audio_encoder
+            .is_none()
+            .then(|| {
+                audio_bitrate
+                    .as_deref()
+                    .and_then(bits)
+                    .and_then(|b| u32::try_from(b).ok())
+            })
+            .flatten(),
         #[cfg(feature = "input-capture")]
         input_capture: None,
         pixel_format,

crates/coreav-cli/src/main.rs

@@ -1179,6 +1179,7 @@ fn run_transcode(
             bitrate: args.audio_bitrate.map(|k| k * 1000),
         }),
         aac_mp4_tail: false,
+        copied_audio_bit_rate: None,
         #[cfg(feature = "input-capture")]
         input_capture: None,
         pixel_format: None,
@@ -1598,6 +1599,7 @@ fn run_remux(args: &RemuxArgs, metadata: Metadata) -> ExitCode {
         }
     };
     let options = RemuxOptions {
+        copied_audio_bit_rate: None,
         interleave_packets: false,
         video_origin: None,
         rebuild_durations: false,

crates/coreav-cli/src/transcode.rs

@@ -103,6 +103,8 @@ pub struct Request {
     pub aac: Option<AacRequest>,
     /// Match the FFmpeg adapter's terminal AAC sample timing in MP4.
     pub aac_mp4_tail: bool,
+    /// Optional metadata bitrate for copied AAC and Opus in MP4.
+    pub copied_audio_bit_rate: Option<u32>,
     /// Optional actual AAC-encoder stdin capture.
     #[cfg(feature = "input-capture")]
     pub input_capture: Option<coreav_transcode::capture::Target>,
@@ -213,6 +215,7 @@ pub fn make<S: Source>(
         },
         left_out_covers: request.left_out_covers.clone(),
         aac_mp4_tail: request.aac_mp4_tail,
+        copied_audio_bit_rate: request.copied_audio_bit_rate,
         encoder: request.encoder.choice(),
         x264: request.x264.clone(),
         ffmpeg: request.ffmpeg.clone(),