Audio Only Clip - Trim

[speedyrazor]

Hi, I am working with an audio only clip, in the Trim wiki it says:

Trim with audio-only clips
In AviSynth v2.60, to trim an audio-only clip, you simply set a fake frame rate with AssumeFPS.

This is my script but its not working:

a1 = LSMASHAudioSource(source="movie.mov", track=1)
a2 = LSMASHAudioSource(source="movie.mov", track=2)
a3 = LSMASHAudioSource(source="movie.mov", track=3)
a4 = LSMASHAudioSource(source="movie.mov", track=4)
a5 = LSMASHAudioSource(source="movie.mov", track=5)
a6 = LSMASHAudioSource(source="movie.mov", track=6)
a7 = LSMASHAudioSource(source="movie.mov", track=7)
a = MergeChannels(a1,a2,a3,a4,a5,a6,a7)
AssumeFPS(24,1)
Trim(19,24)
blackVideo1 = blankclip(a, length=5)
return blackVideo1 + a

This is giving me:

Invalid arguments to function "AssumeFPS"

[StainlessS]

Probably because you aint got no clip.
Try again AFTER the LSMASH stuff (ie when you do got a clip).

EDIT: You seem to have additional problems with naming clips variables and such

EDIT: No idea what below is intended to do.


a1 = LSMASHAudioSource(source="movie.mov", track=1)
a2 = LSMASHAudioSource(source="movie.mov", track=2)
a3 = LSMASHAudioSource(source="movie.mov", track=3)
a4 = LSMASHAudioSource(source="movie.mov", track=4)
a5 = LSMASHAudioSource(source="movie.mov", track=5)
a6 = LSMASHAudioSource(source="movie.mov", track=6)
a7 = LSMASHAudioSource(source="movie.mov", track=7)
a = MergeChannels(a1,a2,a3,a4,a5,a6,a7).AssumeFPS(24,1) # I assume that this is where ASsumeFPS is required
Trim(19,24) # No idea what this is supposed to affect
blackVideo1 = blankclip(a, length=5) # Or is it supposed to affect above Trim clip ?
return blackVideo1 + a


Above needs more thought.

[speedyrazor]

Probably because you aint got no clip.
Try again AFTER the LSMASH stuff (ie when you do got a clip).

Moving the AssumeFPS(24,1) below has the same issue.

EDIT: You seem to have additional problems with naming clips variables and such

Could you be more specific please?

[speedyrazor]

Sorry, im a bit new to all this stuff.

a1 = LSMASHAudioSource(source="movie.mov", track=1)
a2 = LSMASHAudioSource(source="movie.mov", track=2)
a3 = LSMASHAudioSource(source="movie.mov", track=3)
a4 = LSMASHAudioSource(source="movie.mov", track=4)
a5 = LSMASHAudioSource(source="movie.mov", track=5)
a6 = LSMASHAudioSource(source="movie.mov", track=6)
a7 = LSMASHAudioSource(source="movie.mov", track=7)
a = MergeChannels(a1,a2,a3,a4,a5,a6,a7).AssumeFPS(24,1) # I should put the AssumeFPS here?
Trim(19,24) # I want to Trim the audio and only play from frame 19 to frame 24
blackVideo1 = blankclip(a, length=5) # I want to add a 5 frame silence to the beginning of the audio (the return below?)
return blackVideo1 + a

[StainlessS]

Dont know, perhaps it is just the Trim statement that need removed ? (It dont do nuttin)

EDIT: overlapping posts, perhaps something like below

a1 = LSMASHAudioSource(source="movie.mov", track=1)
a2 = LSMASHAudioSource(source="movie.mov", track=2)
a3 = LSMASHAudioSource(source="movie.mov", track=3)
a4 = LSMASHAudioSource(source="movie.mov", track=4)
a5 = LSMASHAudioSource(source="movie.mov", track=5)
a6 = LSMASHAudioSource(source="movie.mov", track=6)
a7 = LSMASHAudioSource(source="movie.mov", track=7)
a = MergeChannels(a1,a2,a3,a4,a5,a6,a7).AssumeFPS(24,1) # I should put the AssumeFPS here?
a=a.Trim(19,24) # I want to Trim the audio and only play from frame 19 to frame 24
blackVideo1 = blankclip(a, length=5) # I want to add a 5 frame silence to the beginning of the audio (the return below?)
return blackVideo1 + a


EDIT: That should give 5 frame silence, + 5 frame audio, OK ?

[speedyrazor]

Using this gives me:

Trim: Cannot trim if there is no video.

a1 = LSMASHAudioSource(source="movie.mov", track=1)
a2 = LSMASHAudioSource(source="movie.mov", track=2)
a3 = LSMASHAudioSource(source="movie.mov", track=3)
a4 = LSMASHAudioSource(source="movie.mov", track=4)
a5 = LSMASHAudioSource(source="movie.mov", track=5)
a6 = LSMASHAudioSource(source="movie.mov", track=6)
a7 = LSMASHAudioSource(source="movie.mov", track=7)
a = MergeChannels(a1,a2,a3,a4,a5,a6,a7).AssumeFPS(24,1)
a=a.Trim(19,24)
blackVideo1 = blankclip(a, length=5)
return blackVideo1 + a

[raffriff42]

in the Trim wiki (http://avisynth.nl/index.php/Trim) it also saysAudioTrim (in 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...

[Wilbert]

@raffriff42,
AudioTrim should work indeed, but
Trim with audio-only clips
In AviSynth v2.60, to trim an audio-only clip, you simply set a fake frame rate with AssumeFPS.

seems false to me.

[StainlessS]

@raffriff42,
AudioTrim should work indeed, but

Trim with audio-only clips
In AviSynth v2.60, to trim an audio-only clip, you simply set a fake frame rate with AssumeFPS.
seems false to me.

To me too.

This dont work,


/*
a1 = LSMASHAudioSource(source="movie.mov", track=1)
a2 = LSMASHAudioSource(source="movie.mov", track=2)
a3 = LSMASHAudioSource(source="movie.mov", track=3)
a4 = LSMASHAudioSource(source="movie.mov", track=4)
a5 = LSMASHAudioSource(source="movie.mov", track=5)
a6 = LSMASHAudioSource(source="movie.mov", track=6)
a7 = LSMASHAudioSource(source="movie.mov", track=7)
a = MergeChannels(a1,a2,a3,a4,a5,a6,a7).
*/

a = Avisource("D:\V\cabaret.avi").Trim(10000,0).KillVideo # Test audio clip

a = a.AssumeFPS(24,1) # Synthesize a dummy Framerate for edits.

a = a.Trim(19,24) # Select required audio, 6 frames # BANG !!!, 'Trim: Cannot trim if there is no video.'

K = blankclip(a, length=5) # Black clip of 5 frames silence

return K + a # Append audio to 5 frames of silence


Getting same as Speedy Razor, ie
Trim: Cannot trim if there is no video.

EDIT: Speedy, suggest that in future, you try add comments like above, so that you can easily track what each variable holds.

[raffriff42]

Yup, I get that too. The wiki is wrong. AudioTrim does work thoughColorBars
Trim(0, 42)
A = Tone(length=3600).AudioTrim(0, -1*Float(FrameCount)/FrameRate)
#A = Tone(length=3600).AssumeFPS(Last).Trim(0, 42) ## error
AudioDub(A)
return Info


EDIT the source code (http://avisynth2.cvs.sourceforge.net/viewvc/avisynth2/avisynth/src/filters/edit.cpp?view=markup#l154) seems pretty clear on this
Trim::Trim(int _firstframe, int _lastframe, bool _padaudio, PClip _child, int mode, IScriptEnvironment* env)
: GenericVideoFilter(_child)
{
int lastframe = 0;

if (!vi.HasVideo())
env->ThrowError("Trim: Cannot trim if there is no video.");
...

[StainlessS]

Yup, I get that too. The wiki is wrong.

Also builtin docs wrong.

[raffriff42]

I will excise that statement from the wiki. It's been there a long time; I'm surprised nobody caught it. The sneaky devil!

EDIT it's my understanding the builtin docs are generated from the wiki, so they will be updated automatically at some future date.

[Music Fan]

What happens if you put blankclip on the first line (and thus before sound and trim) ?

[StainlessS]

Something like this

FPS = 24
KLen = 5

TRIM_S = 19
TRIM_E = 24 # 24-19 + 1 = 6 frames

# Test audio clip, 10 secs of FPS frames, then Kill Video
a = Avisource("D:\V\cabaret.avi").Assumefps(FPS).Trim(10000,-Int(Ceil(FPS*10))).KillVideo

K = blankclip(a,Width=640,height=480,length=KLen,fps=FPS) # Black clip of KLen frames silence, default video CS

Frames = Int(Ceil(a.AudioDuration * FPS)) # Round UP, whole frames

v = blankclip(K, length=Frames) # Number of video frames to match i/p audio duration

va = AudioDub(v,a) # Dummy Video (with audio) clip of frames, same duration as AudioDuration

aTrim = va.Trim(TRIM_S,TRIM_E) # Select required audio (6 video frames worth)


K ++ aTrim # Append audio to silence (assign v+a to Implicit Last)

Info # KLen(5) + (TRIM_E - TRIM_S + 1) = 11 Frames worth of Video + Audio



EDIT: Got to give Width/Height for k=BlankClip(a) else null video

[Wilbert]

EDIT it's my understanding the builtin docs are generated from the wiki, so they will be updated automatically at some future date.
No, they are not.