diff --git a/README.md b/README.md
index 1fd8c99..f52c661 100644
--- a/README.md
+++ b/README.md
@@ -8,7 +8,7 @@ Audio transcoder with simple HTTP API. Work in progress.
 # How to Use
 
 Transcoding can be done like this:
-1. Use `cargo run` or [`neur0toxine/atranscoder-rpc`](https://hub.docker.com/r/neur0toxine/atranscoder-rpc/) Docker image.
+1. Use [`neur0toxine/atranscoder-rpc`](https://hub.docker.com/r/neur0toxine/atranscoder-rpc/) Docker image.
 2. Upload file for transcoding:
 ```bash
 curl --location 'http://localhost:8090/enqueue' \
diff --git a/src/task.rs b/src/task.rs
index 84d7c10..4e486a8 100644
--- a/src/task.rs
+++ b/src/task.rs
@@ -95,6 +95,7 @@ impl Task {
             &mut octx,
             TranscoderParams {
                 codec: self.params.codec,
+                codec_opts: self.params.codec_opts,
                 bit_rate: self.params.bit_rate,
                 max_bit_rate: self.params.max_bit_rate,
                 sample_rate: self.params.sample_rate,
@@ -248,10 +249,10 @@ fn upload_file<P: AsRef<Path>>(
     }
 }
 
-fn params_to_avdictionary(input: &str) -> Dictionary {
+pub fn params_to_avdictionary(input: &str) -> Dictionary {
     let mut dict: Dictionary = Dictionary::new();
     for pair in input.split(';') {
-        let mut parts = pair.split(':');
+        let mut parts = pair.split('=');
 
         if let (Some(key), Some(value)) = (parts.next(), parts.next()) {
             dict.set(key, value);
diff --git a/src/thread_pool.rs b/src/thread_pool.rs
index 8a0ed42..be0c497 100644
--- a/src/thread_pool.rs
+++ b/src/thread_pool.rs
@@ -43,7 +43,14 @@ impl Worker {
         let thread = thread::spawn(move || {
             ffmpeg_next::init()
                 .unwrap_or_else(|err| tracing::error!("couldn't init FFmpeg: {:?}", err));
-            ffmpeg_next::util::log::set_level(Level::Quiet);
+
+            ffmpeg_next::util::log::set_level(
+                if std::env::var("FFMPEG_VERBOSE").unwrap_or_default() == "1" {
+                    Level::Trace
+                } else {
+                    Level::Quiet
+                },
+            );
 
             loop {
                 let task = {
diff --git a/src/transcoder.rs b/src/transcoder.rs
index 0dd1b77..8d819d0 100644
--- a/src/transcoder.rs
+++ b/src/transcoder.rs
@@ -1,9 +1,14 @@
 extern crate ffmpeg_next as ffmpeg;
 
+use std::any::Any;
 use std::error::Error;
 
+use crate::task::params_to_avdictionary;
 use ffmpeg::{codec, filter, format, frame, media};
+use ffmpeg_next::codec::Parameters;
 use ffmpeg_next::error::EAGAIN;
+use ffmpeg_next::Dictionary;
+use tracing::log::debug;
 
 pub struct Transcoder {
     pub(crate) stream: usize,
@@ -16,6 +21,7 @@ pub struct Transcoder {
 
 pub struct TranscoderParams {
     pub codec: String,
+    pub codec_opts: Option<String>,
     pub bit_rate: usize,
     pub max_bit_rate: usize,
     pub sample_rate: i32,
@@ -94,7 +100,11 @@ impl Transcoder {
         output.set_time_base((1, sample_rate));
 
         let in_time_base = decoder.time_base();
-        let encoder = encoder.open_as(codec)?;
+        let encoder = if let Some(codec_opts) = params.codec_opts {
+            encoder.open_as_with(codec, params_to_avdictionary(codec_opts.as_str()))?
+        } else {
+            encoder.open_as(codec)?
+        };
         output.set_parameters(&encoder);
 
         let filter = filter_graph("anull", &decoder, &encoder)?;