encode/decode audio memes with ffmpeg to improve storage

6 files changed, 97 insertions, 30 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 40a4324..6025765 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1726,7 +1726,6 @@ dependencies = [
  "either 1.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "failure 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "fern 0.5.7 (registry+https://github.com/rust-lang/crates.io-index)",
- "flate2 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "itertools 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/Cargo.toml b/Cargo.toml
index 83dad90..83a4f3f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -28,7 +28,6 @@ regex = "1.1.0"
 clap = "2.32.0"
 itertools = "0.8.0"
 serde_json = "~1.0"
-flate2 = "^1.0"
 
 [dependencies.serenity]
 default-features = false
diff --git a/src/audio/play_queue.rs b/src/audio/play_queue.rs
index 119b8c5..fcbb4f9 100644
--- a/src/audio/play_queue.rs
+++ b/src/audio/play_queue.rs
@@ -1,13 +1,13 @@
 use std::{
     collections::VecDeque,
-    io::Cursor,
+    io::{self, BufRead, BufReader, Cursor},
+    process,
     sync::{Arc, RwLock},
     thread,
     time::Duration,
 };
 
 use either::{Left, Right};
-use flate2::bufread::DeflateDecoder;
 use serenity::{
     prelude::*,
     voice,
@@ -94,9 +94,9 @@ impl PlayQueue {
                 }
 
                 let mut queue = queue_lck.write().unwrap();
-                let item = queue.queue.pop_front().unwrap();
+                let mut item = queue.queue.pop_front().unwrap();
 
-                let src = match item.data {
+                let src = match &mut item.data {
                     Left(ref url) => {
                         match ytdl(url, item.start, item.end) {
                             Ok(src) => src,
@@ -108,7 +108,52 @@ impl PlayQueue {
                         }
                     },
                     Right(ref vec) => {
-                        voice::pcm(true, DeflateDecoder::new(Cursor::new(vec.clone())))
+                        let mut transcoder = process::Command::new("ffmpeg")
+                            .args(&[
+                                "-format", "opus",
+                                "-i", "pipe:0",
+                                "-acodec", "pcm_s16le",
+                                "-f", "s16le",
+                                "-"
+                            ])
+                            .stdin(process::Stdio::piped())
+                            .stdout(process::Stdio::piped())
+                            .stderr(process::Stdio::piped())
+                            .spawn()
+                            .expect("unable to call ffmpeg");
+
+                        let process::Child {
+                            stdin,
+                            stderr,
+                            stdout,
+                            ..
+                        } = transcoder;
+
+                        thread::spawn(move || {
+                            let stderr = BufReader::new(stderr.unwrap());
+
+                            for line in stderr.lines() {
+                                let line = line.unwrap();
+
+                                trace!("{}", line);
+                            }
+                        });
+
+                        let v = vec.clone();
+                        thread::spawn(move || {
+                            if let Err(e) = io::copy(&mut Cursor::new(v), &mut stdin.unwrap()) {
+                                use std::io::ErrorKind;
+                                if e.kind() == ErrorKind::BrokenPipe {
+                                    debug!("ffmpeg closed unexpectedly");
+                                } else {
+                                    error!("copying audio to ffmpeg {}", e);
+                                }
+                            }
+                        });
+
+                        let result = voice::pcm(true, stdout.unwrap());
+
+                        result
                     }
                 };
 
diff --git a/src/audio/ytdl.rs b/src/audio/ytdl.rs
index e88d8f8..8239683 100644
--- a/src/audio/ytdl.rs
+++ b/src/audio/ytdl.rs
@@ -45,6 +45,8 @@ pub(crate) trait CodecInfo {
 }
 
 pub(crate) struct Pcm {}
+
+#[allow(dead_code)]
 pub(crate) struct Opus {}
 
 impl CodecInfo for Pcm {
@@ -66,12 +68,9 @@ impl CodecInfo for Opus {
     fn ffmpeg_opts() -> &'static[&'static str] {
         lazy_static! {
             static ref OPTS: Vec<&'static str> = vec! [
-//                "-f", "s16le",
+                "-f", "opus",
                 "-acodec", "libopus",
-                "-sample_fmt", "s16",
-                "-vbr", "off",
-//                "-b:a 96k",
-//                "-vn",
+                "-b:a 96k",
             ];
         }
 
@@ -129,6 +128,11 @@ pub(crate) fn ffmpeg_dl<T: CodecInfo>(uri: &str, start: Option<Duration>, end: O
         .map(|s| s.to_owned())
         .collect::<Vec<_>>();
 
+    if let Some(e) = end {
+        opts.push("-to".to_owned());
+        opts.push(format!("{:02}:{:02}:{:02}", e.num_hours(), e.num_minutes() % 60, e.num_seconds() % 60));
+    }
+
     let codec_opts = T::ffmpeg_opts().into_iter().map(|&s| s.to_owned()).collect::<Vec<_>>();
     opts.extend(codec_opts);
 
@@ -137,11 +141,6 @@ pub(crate) fn ffmpeg_dl<T: CodecInfo>(uri: &str, start: Option<Duration>, end: O
         opts.push(format!("{}", limit));
     }
 
-    if let Some(e) = end {
-        opts.push("-to".to_owned());
-        opts.push(format!("{:02}:{:02}:{:02}", e.num_hours(), e.num_minutes() % 60, e.num_seconds() % 60));
-    }
-
     opts.push("-".to_owned());
 
     debug!("ffmpeg -i \"{}\" {}", uri, opts.join(" "));
diff --git a/src/commands/meme.rs b/src/commands/meme.rs
index 160a652..913be00 100644
--- a/src/commands/meme.rs
+++ b/src/commands/meme.rs
@@ -1,14 +1,14 @@
 use std::{
-    io::{BufReader, Read},
+    io::Read,
+    process::{
+        Command,
+        Stdio,
+    },
     sync::RwLock,
 };
 
 use diesel::PgConnection;
 use failure::Error;
-use flate2::{
-    bufread::DeflateEncoder,
-    Compression,
-};
 use lazy_static::lazy_static;
 use rand::{Rng, thread_rng};
 use serenity::{
@@ -25,10 +25,7 @@ use audio::ytdl_url;
 use crate::{
     audio::{
         CtxExt,
-        ffmpeg_dl,
-        Opus,
         parse_times,
-        Pcm,
         PlayArgs,
         PlayQueue,
     },
@@ -155,10 +152,38 @@ pub fn addaudiomeme(_: &mut Context, msg: &Message, mut args: Args) -> Result<()
     let (start, end) = parse_times(opts);
 
     let youtube_url = ytdl_url(audio_link.as_str())?;
-    let mut audio_reader = DeflateEncoder::new(
-        BufReader::new(ffmpeg_dl::<Pcm>(&youtube_url, start, end, None)?),
-        Compression::best(),
-    );
+
+    let duration_opts = if let Some(e) = end {
+        vec! [
+            "-ss".to_owned(), start.map_or_else(
+                || "00:00:00".to_owned(),
+                |s| format!("{:02}:{:02}:{:02}", s.num_hours(), s.num_minutes() % 60, s.num_seconds() % 60)
+            ),
+
+            "-to".to_owned(), format!("{:02}:{:02}:{:02}", e.num_hours(), e.num_minutes() % 60, e.num_seconds() % 60),
+        ]
+    } else {
+        vec! []
+    };
+
+    let ffmpeg_command = Command::new("ffmpeg")
+        .arg("-i")
+        .arg(youtube_url)
+        .args(duration_opts)
+        .args(&[
+            "-ac", "2",
+            "-ar", "48000",
+            "-f", "opus",
+            "-acodec", "libopus",
+            "-b:a", "96k",
+            "-",
+        ])
+        .stdout(Stdio::piped())
+        .stderr(Stdio::null())
+        .stdin(Stdio::null())
+        .spawn()?;
+
+    let mut audio_reader = ffmpeg_command.stdout.unwrap();
 
     let text = match args.multiple_quoted::<String>() {
         Ok(text) => text.join(" "),
diff --git a/src/main.rs b/src/main.rs
index 5162015..5637ecd 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,4 +1,5 @@
 #![feature(impl_trait_in_bindings)]
+#![feature(try_trait)]
 
 extern crate chrono;
 #[cfg(feature = "diesel")]
@@ -8,7 +9,6 @@ extern crate dotenv;
 extern crate either;
 #[macro_use] extern crate failure;
 extern crate fern;
-extern crate flate2;
 #[cfg_attr(test, macro_use)] extern crate itertools;
 #[macro_use] extern crate lazy_static;
 #[macro_use] extern crate log;