Audio Trimmer
Edit audio files with precise cutting, trimming, and effects. Extract segments, add fades, adjust speed, concatenate clips, and apply basic audio manipulations.
Quick Start from scripts.audio_trimmer import AudioTrimmer
Trim to segment
trimmer = AudioTrimmer("podcast.mp3") trimmer.trim(start="00:05:30", end="00:10:00") trimmer.save("segment.mp3")
Add fades and save
trimmer = AudioTrimmer("song.mp3") trimmer.fade_in(3000).fade_out(5000).save("song_faded.mp3")
Concatenate multiple files
AudioTrimmer.concatenate(["intro.mp3", "main.mp3", "outro.mp3"], "full_episode.mp3")
Features Precise Trimming: Cut segments by timestamp or milliseconds Fade Effects: Fade in/out with customizable duration Speed Control: Speed up or slow down audio Concatenation: Join multiple audio files Basic Effects: Reverse, loop, overlay Silence Operations: Add silence, remove silence Volume Adjustment: Gain control, normalization API Reference Initialization trimmer = AudioTrimmer("audio.mp3")
Trimming
By timestamp (HH:MM:SS or MM:SS)
trimmer.trim(start="01:30", end="05:00")
By milliseconds
trimmer.trim(start_ms=90000, end_ms=300000)
From start to timestamp
trimmer.trim(end="02:00")
From timestamp to end
trimmer.trim(start="10:00")
Fade Effects
Fade in at start (milliseconds)
trimmer.fade_in(3000) # 3 second fade in
Fade out at end
trimmer.fade_out(5000) # 5 second fade out
Crossfade (for concatenation)
AudioTrimmer.concatenate_with_crossfade(files, output, crossfade_ms=2000)
Speed Control
Speed up (1.5x)
trimmer.speed(1.5)
Slow down (0.75x)
trimmer.speed(0.75)
Effects
Reverse audio
trimmer.reverse()
Loop audio N times
trimmer.loop(3)
Overlay another audio
trimmer.overlay("background.mp3", position_ms=0, volume=-6)
Volume
Adjust volume (dB)
trimmer.gain(6) # Increase by 6 dB trimmer.gain(-3) # Decrease by 3 dB
Normalize to target level
trimmer.normalize(-3) # Normalize to -3 dBFS
Silence Operations
Add silence at start
trimmer.add_silence_start(2000) # 2 seconds
Add silence at end
trimmer.add_silence_end(1000)
Strip leading/trailing silence
trimmer.strip_silence(threshold=-50) # dBFS threshold
Concatenation
Simple concatenation
AudioTrimmer.concatenate( ["file1.mp3", "file2.mp3", "file3.mp3"], "output.mp3" )
With crossfade
AudioTrimmer.concatenate_with_crossfade( ["intro.mp3", "main.mp3", "outro.mp3"], "output.mp3", crossfade_ms=2000 )
Save
Save to file (format from extension)
trimmer.save("output.mp3")
Explicit format and quality
trimmer.save("output.mp3", format="mp3", bitrate=320)
CLI Usage
Trim segment
python audio_trimmer.py --input podcast.mp3 --output segment.mp3 --start 05:30 --end 10:00
Add fades
python audio_trimmer.py --input song.mp3 --output faded.mp3 --fade-in 3000 --fade-out 5000
Speed up
python audio_trimmer.py --input lecture.mp3 --output fast.mp3 --speed 1.5
Concatenate files
python audio_trimmer.py --concat file1.mp3 file2.mp3 file3.mp3 --output merged.mp3
Extract multiple segments
python audio_trimmer.py --input podcast.mp3 --segments "00:00-05:00,10:00-15:00,20:00-25:00" --output-dir ./clips/
CLI Arguments Argument Description Default --input Input audio file Required --output Output file path Required --start Start timestamp (HH:MM:SS or MM:SS) - --end End timestamp - --fade-in Fade in duration (ms) - --fade-out Fade out duration (ms) - --speed Speed multiplier 1.0 --gain Volume adjustment (dB) 0 --reverse Reverse audio False --normalize Normalize to dBFS level - --concat Files to concatenate - --crossfade Crossfade duration for concat (ms) 0 --segments Multiple segments to extract - Examples Extract Podcast Segment trimmer = AudioTrimmer("episode_42.mp3") trimmer.trim(start="15:30", end="22:45") trimmer.fade_in(1000) trimmer.fade_out(2000) trimmer.save("highlight_clip.mp3")
Create Ringtone trimmer = AudioTrimmer("song.mp3") trimmer.trim(start="01:15", end="01:45") # 30-second segment trimmer.fade_in(500) trimmer.fade_out(1000) trimmer.normalize(-3) trimmer.save("ringtone.mp3", bitrate=192)
Speed Up Lecture trimmer = AudioTrimmer("lecture.mp3") trimmer.speed(1.25) # 25% faster trimmer.normalize(-16) # Podcast-friendly level trimmer.save("lecture_fast.mp3")
Build Episode from Segments
With crossfades between segments
AudioTrimmer.concatenate_with_crossfade( files=[ "intro_music.mp3", "sponsor_read.mp3", "main_content.mp3", "outro_music.mp3" ], output="full_episode.mp3", crossfade_ms=1500 )
Extract Multiple Highlights
Extract several segments from a long recording
trimmer = AudioTrimmer("meeting_recording.mp3")
segments = [ ("00:05:00", "00:08:30", "intro"), ("00:25:00", "00:32:00", "discussion"), ("01:15:00", "01:20:00", "conclusion") ]
for start, end, name in segments: t = AudioTrimmer("meeting_recording.mp3") t.trim(start=start, end=end) t.fade_in(500) t.fade_out(500) t.save(f"{name}.mp3")
Add Background Music
Overlay quiet background music
trimmer = AudioTrimmer("podcast.mp3") trimmer.overlay( "ambient_music.mp3", position_ms=0, volume=-15, # 15 dB quieter loop=True # Loop to fill duration ) trimmer.save("podcast_with_music.mp3")
Time Format Reference
The trimmer accepts these timestamp formats:
Format Example Meaning MM:SS 05:30 5 minutes 30 seconds HH:MM:SS 01:30:00 1 hour 30 minutes SS 90 90 seconds SS.ms 90.500 90.5 seconds Dependencies pydub>=0.25.0
Note: Requires FFmpeg installed on system.
Limitations Speed adjustment may affect pitch (no pitch preservation) Very large files may consume significant memory Crossfade works best with similar audio levels