Trim

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<div {{BlueBox2|40|0|3px solid purple}} >
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{{AvsPlusFullname}}<br>
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Up-to-date documentation: [https://avisynthplus.readthedocs.io/en/latest/avisynthdoc/corefilters/trim.html https://avisynthplus.readthedocs.io]
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</div>
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== Trim ==
 
== Trim ==
 
<div style="max-width:62em" >
 
<div style="max-width:62em" >
 
''Trims'' a clip &ndash; removes frames from one or both ends.  
 
''Trims'' a clip &ndash; removes frames from one or both ends.  
  
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The audio is similarly trimmed so that it stays synchronized (see [[#Pad_argument|Pad argument]] below).
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'''Trim''' cannot trim a clip if there is no video. Use '''AudioTrim''' (from AviSynth v2.60) for that case; for versions prior to v2.60, you must [[AudioDub]] your audio-only clip to a video clip and '''Trim''' ''that''.  
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The resulting clip starts with frame number 0, and this must be taken into account when making additional edits using that clip. To view a clip's frame number at any point in your script, temporarily insert an [[Info]] or [[ShowFrameNumber]] statement.
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For convenience, '''Trim''' can be called in four slightly different ways:
 
For convenience, '''Trim''' can be called in four slightly different ways:
  
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:*Remember, AviSynth starts counting at frame 0.
 
:*Remember, AviSynth starts counting at frame 0.
 
:*If you set {{FuncArg|last_frame}} to 0, you will get a clip starting at {{FuncArg|first_frame}} and running to the end of the clip.
 
:*If you set {{FuncArg|last_frame}} to 0, you will get a clip starting at {{FuncArg|first_frame}} and running to the end of the clip.
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{{Par2h5|pad|bool|true}}
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::True by default, {{FuncArg|pad}} causes the audio stream to be padded to align with the video stream. Otherwise the tail of a short audio stream is left so. You should use {{FuncArg|pad}}=false when the soundtracks being joined were originally contiguous &ndash; compare to [[UnalignedSplice]].
  
  
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}}
 
}}
 
:Returns a clip starting at {{FuncArg|first_frame}} and running up to and including frame {{FuncArg|end}}. From Avisynth v2.60.  
 
:Returns a clip starting at {{FuncArg|first_frame}} and running up to and including frame {{FuncArg|end}}. From Avisynth v2.60.  
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:* For example, <tt>Trim(3, {{FuncArg|end}}=7)</tt> ''is equivalent to'' <tt>Trim(3, 7)</tt>; both return frames '''3''', '''4''', '''5''', '''6''' and '''7'''.
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:* For example, <tt>Trim(3, {{FuncArg|end}}=7)</tt> is equivalent to <tt>Trim(3, 7)</tt>; both return frames '''3''', '''4''', '''5''', '''6''' and '''7'''.
 
:*{{FuncArg|end}} default = 0; must be >= {{FuncArg|first_frame}}.
 
:*{{FuncArg|end}} default = 0; must be >= {{FuncArg|first_frame}}.
 
:*Unlike the {{FuncArg|last_frame}} syntax, the {{FuncArg|end}} syntax has no discontinuous boundary values: {{FuncArg|end}}=0 means end at frame 0. This feature is useful in avoiding unexpected boundary conditions in your user functions.
 
:*Unlike the {{FuncArg|last_frame}} syntax, the {{FuncArg|end}} syntax has no discontinuous boundary values: {{FuncArg|end}}=0 means end at frame 0. This feature is useful in avoiding unexpected boundary conditions in your user functions.
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}}
 
}}
 
:Returns a clip starting at {{FuncArg|first_frame}} and running for {{FuncArg|length}} frames. From Avisynth v2.60.
 
:Returns a clip starting at {{FuncArg|first_frame}} and running for {{FuncArg|length}} frames. From Avisynth v2.60.
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:*For example, <tt>Trim(3, {{FuncArg|length}}=5)</tt> ''is equivalent to'' <tt>Trim(3, -5)</tt>; both return frames '''3''', '''4''', '''5''', '''6''' and '''7'''.
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:*For example, <tt>Trim(3, {{FuncArg|length}}=5)</tt> is equivalent to <tt>Trim(3, -5)</tt>; both return frames '''3''', '''4''', '''5''', '''6''' and '''7'''.
 
:*{{FuncArg|length}} default = 0; must be >= 0.  
 
:*{{FuncArg|length}} default = 0; must be >= 0.  
 
:*Unlike the {{FuncArg|num_frames}} syntax, the {{FuncArg|length}} syntax has no discontinuous boundary values: {{FuncArg|length}}=0 means return a zero length clip. This feature is useful in avoiding unexpected boundary conditions in your user functions.
 
:*Unlike the {{FuncArg|num_frames}} syntax, the {{FuncArg|length}} syntax has no discontinuous boundary values: {{FuncArg|length}}=0 means return a zero length clip. This feature is useful in avoiding unexpected boundary conditions in your user functions.
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====Pad argument====
 
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True by default, {{FuncArg|pad}} causes the audio stream to be padded to align with the video stream. Otherwise the tail of a short audio stream is left so. You should use {{FuncArg|pad}}=false when the soundtracks being joined were originally contiguous (see [[AlignedSplice]], [[UnalignedSplice]] )
 
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====Trim and Audio-only clips====
 
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'''Trim''' cannot trim a clip if there is no video. Use '''AudioTrim''' for that. To use '''Trim''' you must take an existing video source, use [[AudioDub]] to add your audio and '''Trim''' ''that''. Otherwise, AviSynth returns the error message "Trim: Cannot trim if there is no video."
 
 
</div>
 
</div>
  
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== AudioTrim ==
 
== AudioTrim ==
 
<div style="max-width:62em" >
 
<div style="max-width:62em" >
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'''AudioTrim''' (from Avisynth v2.60) trims a clip based on ''time'', not on ''frames''. All time arguments are in seconds. This is most useful for audio-only clips, where "frames" have no meaning anyway, and you may want to edit with finer precision than whole frames (at 30fps, 1 frame=33.3ms).  
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'''AudioTrim''' (from Avisynth v2.60) trims a clip based on ''time'', not on ''frames''. This is most useful for audio-only clips, where "frames" have no meaning anyway, and you may want to edit with finer precision than whole frames (at 30fps, 1 frame=33.3ms).
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All time arguments are in seconds, floating-point.
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* Trims on audio-only clips are accurate to the nearest audio sample.
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* Trims on clips with video are accurate to the nearest whole video frame.
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'''AudioTrim''' cannot trim a clip if there is no audio. Use '''Trim''' for that case.
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The resulting clip starts with time = 0.0, and this must be taken into account when making additional edits to that clip. To view a clip's time at any point in your script, temporarily insert an [[Info]] or [[ShowTime]] statement.  
  
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Naturally, {{BoldColor|#4F81BD|100|trims on clips with video are rounded to the nearest whole video frame}}.
 
  
 
For convenience, '''AudioTrim''' can be called in four slightly different ways:
 
For convenience, '''AudioTrim''' can be called in four slightly different ways:
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== Examples ==
 
== Examples ==
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<div {{BoxWidthIndent|56|0}} >
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* Return only the first frame (frame 0)
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  Trim(100,0)             # delete the first 100 frames, audio padded
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<div {{BoxWidthIndent|26|2}} >
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                        # or trimmed to match the video length.
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  Trim(0, -1)
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Trim(0, end=0)
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Trim(0, length=1)
 
</div>
 
</div>
  
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<div {{BoxWidthIndent|56|0}} >
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* Return only the last frame
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  Trim(100,0,false)       # delete the first 100 frames of audio and video,
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<div {{BoxWidthIndent|26|2}} >
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                        # the resulting stream lengths remain independent.
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  Trim(FrameCount, -1)
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Trim(FrameCount, end=Framecount)
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Trim(FrameCount, length=1)
 
</div>
 
</div>
  
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<div {{BoxWidthIndent|56|0}} >
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* Return frames 100-199 (duration=100)
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  Trim(100,-100)         # is the same as trim(100,199) ie, start=100, duration=100
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<div {{BoxWidthIndent|26|2}} >
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  Trim(100, 199)
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Trim(100, -100)
 
</div>
 
</div>
  
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<div {{BoxWidthIndent|56|0}} >
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* Delete the first 100 frames; audio padded or trimmed to match the video length.
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  Trim(100,199,false)     # audio will be trimmed if longer but not
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<div {{BoxWidthIndent|26|2}} >
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                        # padded if shorter to frame 199
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  Trim(100, 0) # (pad=true by default)
 
</div>
 
</div>
  
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<div {{BoxWidthIndent|56|0}} >
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* Delete the first 100 frames of audio and video; the resulting stream lengths remain independent.{{Dubious|Talk:Trim}}
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  Trim(0,-1)              # returns only the first frame
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<div {{BoxWidthIndent|26|2}} >
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Trim(0,end=0)          #
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  Trim(100, 0, pad=false)
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Trim(0,length=1)       #
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</div>
 
</div>
  
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<div {{BoxWidthIndent|56|0}} >
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* Trim audio if longer than video ({{FuncArg|pad}} does affect this action)
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  AudioTrim(1,5.5)        # keeps the audio samples between 1 and 5.5 seconds
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<div {{BoxWidthIndent|26|2}} >
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AudioTrim(1,end=5.5)   #
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  Trim(0, FrameCount-1)  
 
</div>
 
</div>
  
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<div {{BoxWidthIndent|56|0}} >
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* Audio will be trimmed if longer, but not padded if shorter to frame 199
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  AudioTrim(1,-5.5)      # cuts the first second and keeps the following 5.5 seconds
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<div {{BoxWidthIndent|26|2}} >
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AudioTrim(1,length=5.5) #
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  Trim(100, 199, pad=false)
 
</div>
 
</div>
  
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* AudioTrim: trim video if longer than audio
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<div {{BoxWidthIndent|26|2}} >
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AudioTrim(0, AudioDuration)
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</div>
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* AudioTrim: keep the audio between 1.0 and 6.5 seconds
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<div {{ListItemContinue}} >
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(ie, delete the first second, keep the following 5.5 seconds)
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</div>
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<div {{BoxWidthIndent|26|2}} >
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AudioTrim(1, 6.5)     
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AudioTrim(1, -5.5)     
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AudioTrim(1, length=5.5)
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</div>
  
 
== Changes ==
 
== Changes ==

Latest revision as of 05:50, 18 September 2022

AviSynth+
Up-to-date documentation: https://avisynthplus.readthedocs.io


Contents

[edit] Trim

Trims a clip – removes frames from one or both ends.

Trim cannot trim a clip if there is no video. Use AudioTrim (from AviSynth v2.60) for that case; for versions prior to v2.60, you must AudioDub your audio-only clip to a video clip and Trim that.

The resulting clip starts with frame number 0, and this must be taken into account when making additional edits using that clip. To view a clip's frame number at any point in your script, temporarily insert an Info or ShowFrameNumber statement.


For convenience, Trim can be called in four slightly different ways:


Trim(clip, int first_frame, int last_frame [, bool pad] )

Returns a clip starting at first_frame and running up to and including last_frame.
  • For example, Trim(3, 5) returns source clip frames 3, 4 and 5.
  • Remember, AviSynth starts counting at frame 0.
  • If you set last_frame to 0, you will get a clip starting at first_frame and running to the end of the clip.
 pad
 bool  pad = true
True by default, pad causes the audio stream to be padded to align with the video stream. Otherwise the tail of a short audio stream is left so. You should use pad=false when the soundtracks being joined were originally contiguous – compare to UnalignedSplice.


Trim(clip, int first_frame, int -num_frames [, bool pad] )

With a negative value for the second argument, you get a clip starting at first_frame and running for num_frames frames.
  • For example, Trim(0, -4) returns source clip frames 0, 1, 2 and 3.


Trim(clip, int first_frame, [int end , bool pad] )

Returns a clip starting at first_frame and running up to and including frame end. From Avisynth v2.60.
  • For example, Trim(3, end=7) is equivalent to Trim(3, 7); both return frames 3, 4, 5, 6 and 7.
  • end default = 0; must be >= first_frame.
  • Unlike the last_frame syntax, the end syntax has no discontinuous boundary values: end=0 means end at frame 0. This feature is useful in avoiding unexpected boundary conditions in your user functions.


Trim(clip, int first_frame, [int length , bool pad] )

Returns a clip starting at first_frame and running for length frames. From Avisynth v2.60.
  • For example, Trim(3, length=5) is equivalent to Trim(3, -5); both return frames 3, 4, 5, 6 and 7.
  • length default = 0; must be >= 0.
  • Unlike the num_frames syntax, the length syntax has no discontinuous boundary values: length=0 means return a zero length clip. This feature is useful in avoiding unexpected boundary conditions in your user functions.


[edit] AudioTrim

AudioTrim (from Avisynth v2.60) trims a clip based on time, not on frames. This is most useful for audio-only clips, where "frames" have no meaning anyway, and you may want to edit with finer precision than whole frames (at 30fps, 1 frame=33.3ms).

All time arguments are in seconds, floating-point.

  • Trims on audio-only clips are accurate to the nearest audio sample.
  • Trims on clips with video are accurate to the nearest whole video frame.

AudioTrim cannot trim a clip if there is no audio. Use Trim for that case.

The resulting clip starts with time = 0.0, and this must be taken into account when making additional edits to that clip. To view a clip's time at any point in your script, temporarily insert an Info or ShowTime statement.


For convenience, AudioTrim can be called in four slightly different ways:


AudioTrim(clip, float start_time, float end_time)

Returns a clip starting at start_time and running up to and including time end_time.
  • For example, AudioTrim(3.0, 5.0) returns source clip from time 00:00:03.000 to 00:00:05.000.
  • If you set end_time to 0.0, you will get a clip starting at start_time seconds and running to the end of the clip.


AudioTrim(clip, float start_time, float -duration)

With a negative value for the second argument, you will get a clip starting at start_time and running for duration seconds.
  • For example, AudioTrim(0.0, -4.0) returns the source clip from time 00:00:00.000 to 00:00:04.000.


AudioTrim(clip, float start_time [, float end] )

Returns a clip starting at start_time and running up to and including time end.
  • For example, AudioTrim(3.0, end=7.0) is equivalent to AudioTrim(3.0, 7.0)
  • end default = 0.0; must be >= start_time.
  • Unlike the end_time syntax, the end syntax has no discontinuous boundary values: end=0.0 means return a zero length clip. This feature is useful in avoiding unexpected boundary conditions in your user functions.


AudioTrim(clip, float start_time [, float length] )

Returns a clip starting at start_time and running for length seconds.
  • For example, AudioTrim(3.0, length=4.0) is equivalent to AudioTrim(3.0, -4.0)
  • length default = 0.0; must be >= 0.
  • Unlike the duration syntax, the length syntax has no discontinuous boundary values: length=0.0 means return a zero length clip. This feature is useful in avoiding unexpected boundary conditions in your user functions.


[edit] Examples

  • Return only the first frame (frame 0) 
Trim(0, -1)
Trim(0, end=0)
Trim(0, length=1)
  • Return only the last frame 
Trim(FrameCount, -1)
Trim(FrameCount, end=Framecount)
Trim(FrameCount, length=1)
  • Return frames 100-199 (duration=100) 
Trim(100, 199)
Trim(100, -100)
  • Delete the first 100 frames; audio padded or trimmed to match the video length. 
Trim(100, 0) # (pad=true by default)
  • Delete the first 100 frames of audio and video; the resulting stream lengths remain independent.[dubious – discuss] 
Trim(100, 0, pad=false)
  • Trim audio if longer than video (pad does affect this action) 
Trim(0, FrameCount-1)
  • Audio will be trimmed if longer, but not padded if shorter to frame 199 
Trim(100, 199, pad=false)
  • AudioTrim: trim video if longer than audio 
AudioTrim(0, AudioDuration)
  • AudioTrim: keep the audio between 1.0 and 6.5 seconds

(ie, delete the first second, keep the following 5.5 seconds) 

AudioTrim(1, 6.5)       
AudioTrim(1, -5.5)       
AudioTrim(1, length=5.5)

[edit] Changes

v2.60 Added AudioTrim. Added length and end parameters.
v2.56 Added pad audio.
Retrieved from "http://avisynth.nl/index.php?title=Trim&oldid=12764"
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