Trim
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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''. | '''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 | + | 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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'''AudioTrim''' cannot trim a clip if there is no audio. Use '''Trim''' for that case. | '''AudioTrim''' cannot trim a clip if there is no audio. Use '''Trim''' for that case. | ||
− | The | + | 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. |
Revision as of 22:00, 30 April 2016
Contents |
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.
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.
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.
Examples
- Return only the first frame (frame 0)
Trim(0, -1) Trim(0, end=0) Trim(0, 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)
Changes
v2.60 | Added AudioTrim. Added length and end parameters. |
v2.56 | Added pad audio. |