feat: -speed/-spd option

flazepe · Oct 26, 2024 · df352f9 · df352f9
1 parent 1dc6d34
commit df352f9
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Showing 4 changed files with 43 additions and 10 deletions.
diff --git a/README.md b/README.md
@@ -17,7 +17,7 @@ Combining multiple clips from multiple inputs
 clipper -i input1.mp4 -s 2:00-2:30 -s 5:12-5:20 -i input2.mp4 -s 1:15-1:25 -s 7:20-7:27 output.mp4
 ```
 
-Selecting a video/audio track and burning subtitles from input (this option works per input, like segments)
+Selecting a video/audio track and burning subtitles from input (these options work per input)
 
 ```
 clipper -input input.mp4 -video-track 1 -audio-track 1 -subtitle-track 1 -segment 2:00-2:30 -segment 5:12-5:20 output.mp4
@@ -26,6 +26,13 @@ clipper -input input.mp4 -vt 1 -at 1 -st 1 -s 2:00-2:30 -s 5:12-5:20 output.mp4
 clipper -input input1.mp4 -vt 1 -at 1 -st 1 -s 2:00-2:30 -s 5:12-5:20 -i input2.mp4 -vt 2 -at 2 -st 2 -s 1:15-1:25 -s 7:20-7:27 output.mp4
 ```
 
+Setting the input's segment speed. This speeds up all segments of the input by the specified multiplier (this option works per input)
+
+```
+clipper -i input.mp4 -speed 2 -s 2:00-2:30 -s 5:12-5:20 output.mp4
+clipper -i input.mp4 -spd 2 -s 2:00-2:30 -s 5:12-5:20 output.mp4
+```
+
 Adding a fade transition between segments with optional duration in seconds (this option applies to all segments, regardless of their inputs)
 
 ```

diff --git a/src/clipper.rs b/src/clipper.rs
@@ -32,6 +32,7 @@ impl Clipper {
                     "video-track" | "vt" => current_option = Some(option.into()),
                     "audio-track" | "at" => current_option = Some(option.into()),
                     "subtitle-track" | "st" => current_option = Some(option.into()),
+                    "speed" | "spd" => current_option = Some(option.into()),
                     "segment" | "s" => current_option = Some(option.into()),
                     "fade" | "f" => inputs.set_fade(arg),
                     "nvenc" => encoder.set_nvenc(true),
@@ -66,6 +67,11 @@ impl Clipper {
                             last_input.set_subtitle_track(arg);
                         }
                     }
+                    "speed" | "spd" => {
+                        if let Some(last_input) = inputs.get_last_input_mut() {
+                            last_input.set_speed(arg);
+                        }
+                    }
                     "segment" | "s" => {
                         if let Some(last_input) = inputs.get_last_input_mut() {
                             last_input.add_segment(arg);

diff --git a/src/ffmpeg/input.rs b/src/ffmpeg/input.rs
@@ -6,6 +6,7 @@ pub struct Input {
     pub video_track: u8,
     pub audio_track: u8,
     pub subtitle_track: Option<u8>,
+    pub speed: f64,
 }
 
 impl Input {
@@ -16,6 +17,7 @@ impl Input {
             video_track: 0,
             audio_track: 0,
             subtitle_track: None,
+            speed: 1.,
         }
     }
 
@@ -40,4 +42,16 @@ impl Input {
             error!("Invalid subtitle track: {subtitle_track}");
         }));
     }
+
+    pub fn set_speed(&mut self, speed: String) {
+        let speed = speed.parse::<f64>().unwrap_or_else(|_| {
+            error!("Invalid speed multiplier: {speed}");
+        });
+
+        if !(0.5..100.).contains(&speed) {
+            error!("Speed multiplier must be between 0.5 and 100. Received: {speed}");
+        }
+
+        self.speed = speed;
+    }
 }
diff --git a/src/ffmpeg/inputs.rs b/src/ffmpeg/inputs.rs
@@ -64,7 +64,7 @@ impl IntoIterator for Inputs {
             args.append(&mut string_vec!["-i", input.file]);
 
             let video_label = format!("{input_index}:v:{}", input.video_track);
-            let subtitled_video_label = input.subtitle_track.as_ref().map(|subtitle_track| {
+            let label_subtitled_video = input.subtitle_track.as_ref().map(|subtitle_track| {
                 let label = format!("{video_label}:si={subtitle_track}");
                 filters.push(format!(
                     "[{video_label}]subtitles={}:si={subtitle_track}[{label}];[{label}]split={}{}",
@@ -73,7 +73,7 @@ impl IntoIterator for Inputs {
                     (0..input.segments.len())
                         .fold("".into(), |acc, cur| format!("{acc}[{label}:{cur}]")),
                 ));
-                label
+                move |segment_index| format!("{label}:{segment_index}")
             });
 
             for (segment_index, segment) in input.segments.iter().enumerate() {
@@ -83,23 +83,26 @@ impl IntoIterator for Inputs {
                     .unwrap_or_else(|| {
                         error!("Invalid segment duration range: {segment}");
                     });
-                let fade_to = to - self.fade.unwrap_or(0.) - 0.5;
+                let fade_to = to - self.fade.unwrap_or(0.) * input.speed - 0.5;
 
                 if !self.no_video {
                     let mut video_filters = vec![format!(
                         "[{}]trim={from}:{to}",
-                        subtitled_video_label.as_ref().map_or_else(
-                            || video_label.clone(),
-                            |label| format!("{label}:{segment_index}"),
-                        ),
+                        label_subtitled_video
+                            .as_ref()
+                            .map_or_else(|| video_label.clone(), |func| func(segment_index)),
                     )];
-                    if let Some(fade) = self.fade {
+                    if let Some(mut fade) = self.fade {
+                        fade *= input.speed;
                         video_filters.extend_from_slice(&[
                             format!("fade=t=in:st={from}:d={fade}"),
                             format!("fade=t=out:st={fade_to}:d={fade}"),
                         ]);
                     }
-                    video_filters.push(format!("setpts=PTS-STARTPTS[v{segment_count}]"));
+                    video_filters.push(format!(
+                        "setpts=(PTS-STARTPTS)/{}[v{segment_count}]",
+                        input.speed,
+                    ));
                     filters.push(video_filters.join(","));
                 }
 
@@ -114,6 +117,9 @@ impl IntoIterator for Inputs {
                             format!("afade=t=out:st={fade_to}:d={fade}"),
                         ]);
                     }
+                    if input.speed != 1. {
+                        audio_filters.push(format!("atempo={}", input.speed));
+                    }
                     audio_filters.push(format!("asetpts=PTS-STARTPTS[a{segment_count}]"));
                     filters.push(audio_filters.join(","));
                 }