Support H.264 on native via user installed ffmpeg executable

Cargo.lock

@@ -2463,6 +2463,15 @@ dependencies = [
  "simd-adler32",
 ]
 
+[[package]]
+name = "ffmpeg-sidecar"
+version = "1.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4bd1e249e0ceeb0f5c9f84a3c6941c3bde3ebc2815f4b94531a7e806af61c4c0"
+dependencies = [
+ "anyhow",
+]
+
 [[package]]
 name = "filetime"
 version = "0.2.23"
@@ -6516,6 +6525,7 @@ dependencies = [
  "criterion",
  "crossbeam",
  "econtext",
+ "ffmpeg-sidecar",
  "indicatif",
  "itertools 0.13.0",
  "js-sys",

Cargo.toml

@@ -177,6 +177,7 @@ econtext = "0.2" # Prints error contexts on crashes
 ehttp = "0.5.0"
 enumset = "1.0.12"
 env_logger = { version = "0.10", default-features = false }
+ffmpeg-sidecar = "1.1.2"
 fixed = { version = "<1.28", default-features = false } # 1.28+ is MSRV 1.79+
 flatbuffers = "23.0"
 futures-channel = "0.3"

crates/store/re_video/Cargo.toml

@@ -23,14 +23,17 @@ features = ["all"]
 
 
 [features]
-default = ["av1"]
+default = ["av1", "ffmpeg"]
 
 ## Enable serialization for data structures that support it.
 serde = ["dep:serde"]
 
 ## Native AV1 decoding.
 av1 = ["dep:dav1d"]
 
+## Decode H.264 using ffmpeg over CLI.
+ffmpeg = ["dep:ffmpeg-sidecar"]
+
 ## Enable faster native video decoding with assembly.
 ## You need to install [nasm](https://nasm.us/) to compile with this feature.
 nasm = [
@@ -49,9 +52,11 @@ econtext.workspace = true
 itertools.workspace = true
 parking_lot.workspace = true
 re_mp4.workspace = true
-serde = { workspace = true, optional = true }
 thiserror.workspace = true
 
+ffmpeg-sidecar = { workspace = true, optional = true }
+serde = { workspace = true, optional = true }
+
 # We enable re_rav1d on native, UNLESS we're on Linux Arm64
 # See https://github.com/rerun-io/rerun/issues/7755
 [target.'cfg(all(not(target_arch = "wasm32"), not(all(target_os = "linux", target_arch = "aarch64"))))'.dependencies]
@@ -83,6 +88,7 @@ web-sys = { workspace = true, features = [
 ] }
 
 [dev-dependencies]
+# For the `frames` example:
 indicatif.workspace = true
 criterion.workspace = true
 

crates/store/re_video/build.rs

@@ -10,5 +10,6 @@ fn main() {
         native: { not(target_arch = "wasm32") },
         linux_arm64: { all(target_os = "linux", target_arch = "aarch64") },
         with_dav1d: { all(feature = "av1", native, not(linux_arm64)) }, // https://github.com/rerun-io/rerun/issues/7755
+        with_ffmpeg: { all(feature= "ffmpeg", native) }
     }
 }

crates/store/re_video/examples/frames.rs

@@ -14,6 +14,8 @@ use indicatif::ProgressBar;
 use parking_lot::Mutex;
 
 fn main() {
+    re_log::setup_logging();
+
     // frames <video.mp4>
     let args: Vec<_> = std::env::args().collect();
     let Some(video_path) = args.get(1) else {
@@ -83,13 +85,20 @@ fn main() {
                 .create(true)
                 .truncate(true)
                 .open(output_dir.join(format!("{i:0width$}.ppm")))
-                .expect("failed to open file");
-            write_binary_ppm(
-                &mut file,
-                frame.content.width,
-                frame.content.height,
-                &frame.content.data,
-            );
+                .expect("failed to oformatpen file");
+
+            let frame = &frame.content;
+            match frame.format {
+                re_video::PixelFormat::Rgb8Unorm => {
+                    write_ppm_rgb24(&mut file, frame.width, frame.height, &frame.data);
+                }
+                re_video::PixelFormat::Rgba8Unorm => {
+                    write_ppm_rgba32(&mut file, frame.width, frame.height, &frame.data);
+                }
+                re_video::PixelFormat::Yuv { .. } => {
+                    re_log::error_once!("YUV frame writing is not supported");
+                }
+            }
         }
     }
 }
@@ -98,7 +107,24 @@ fn num_digits(n: usize) -> usize {
     (n as f64).log10().floor() as usize + 1
 }
 
-fn write_binary_ppm(file: &mut File, width: u32, height: u32, rgba: &[u8]) {
+fn write_ppm_rgb24(file: &mut File, width: u32, height: u32, rgb: &[u8]) {
+    assert_eq!(width as usize * height as usize * 3, rgb.len());
+
+    let header = format!("P6\n{width} {height}\n255\n");
+
+    let mut data = Vec::with_capacity(header.len() + width as usize * height as usize * 3);
+    data.extend_from_slice(header.as_bytes());
+
+    for rgb in rgb.chunks(3) {
+        data.extend_from_slice(&[rgb[0], rgb[1], rgb[2]]);
+    }
+
+    file.write_all(&data).expect("failed to write frame data");
+}
+
+fn write_ppm_rgba32(file: &mut File, width: u32, height: u32, rgba: &[u8]) {
+    assert_eq!(width as usize * height as usize * 4, rgba.len());
+
     let header = format!("P6\n{width} {height}\n255\n");
 
     let mut data = Vec::with_capacity(header.len() + width as usize * height as usize * 3);

crates/store/re_video/src/decode/async_decoder_wrapper.rs

@@ -73,7 +73,7 @@ impl AsyncDecoderWrapper {
         let comms = Comms::default();
 
         let thread = std::thread::Builder::new()
-            .name("av1_decoder".into())
+            .name(format!("decoer thread for {debug_name}"))
             .spawn({
                 let comms = comms.clone();
                 move || {

crates/store/re_video/src/decode/av1.rs

@@ -76,14 +76,14 @@ impl SyncDav1dDecoder {
         re_tracing::profile_function!();
         econtext::econtext_function_data!(format!(
             "chunk timestamp: {:?}",
-            chunk.composition_timestamp
+            chunk.presentation_timestamp
         ));
 
         re_tracing::profile_scope!("send_data");
         match self.decoder.send_data(
             chunk.data,
             None,
-            Some(chunk.composition_timestamp.0),
+            Some(chunk.presentation_timestamp.0),
             Some(chunk.duration.0),
         ) {
             Ok(()) => {}
@@ -237,6 +237,7 @@ fn output_picture(
         info: FrameInfo {
             presentation_timestamp: Time(picture.timestamp().unwrap_or(0)),
             duration: Time(picture.duration()),
+            ..Default::default()
         },
     };
     on_output(Ok(frame));