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NODE CLIP

The CLIP node allows the loading of small video clips that can be used in a variety of different ways. Some things to note:

* The two possible resolutions of the clips are 320×240 or 640×480 (and only one size active at a time)
* 320×240 allows 1600 frames total
* 640×480 allows 400 frames total
* Maximum clip length can be set in SYSTEM menu (like 20 frames per video)
* Maximum of 16 clips supported

The reason for these limitations is two fold. The SDCARD is too slow to stream actively and the frames have to be stored in system memory uncompressed.

Clips go on the front SDCARD in a top-level directory called “clips” (which you can create if it does not exist, or use the utility in the SYSTEM menu for creating directories), The full path would be: /sdcard/clips/ (*nix) or D:\sdcard\clips (on Windows).

The ONLY video file format supported by STRUCTURE is ‘Motion JPEG A’. We recommend using an application like MPEG Streamclip or FFMPRG to process your incoming video.

Below is a screen capture of MPEG Streamclip showing the required settings :

YOU CANNOT DEVIATE FROM THESE SETTINGS!
Resolution: 640×480 or 320×240
Container: MOV
Compression: Motion JPEG A
Number of fields: One (NO INTERLACED, TURN OFF ALL INTERLACING SETTINGS)
Sound: No Sound (CANNOT HAVE SOUND TRACK IN IT AT ALL)

Alternatively, you can try using FFMPEG on the command line of your Mac.

If you run into problems, reach out to us and we’ll help you get it sorted.

Like other nodes, pressing the PARAMS button brings up the PARAMS menu for the CLIP NODE:

Files :
CLIP : the currently playing video file. Press the SELECT FILE soft key to load a different video clip.

Controls :
STRUCTURE is not a fixed frame rate system, it adapts to how much processor load is happening. For this reason, there is only one parameter which is CONTROL so you can dial in a speed depending on the GPU load to get the effect you want. (TIP, if you stuff a bunch of images in a video you can slow way down to just show frames!)

Settings :

SETTINGS :
Play Mode :
        -> : Plays video clip forward, loops to the beginning of clip
        <- : Plays video clips backwards, loops to end of clip
        <-> : Plays video loop palindrome style
        One -> : Uses the “Reset/Trigger Clip” to play clip forwards once
        One <- : Uses the “Reset/Trigger Clip” to play clip backwards once
        One <-> : Uses the “Reset/Trigger Clip” to play forward – reverse
        Rnd Seg : selects a random position and plays from there. The size of the segments are the clip length divided by the Rand Segments setting.
        Wander : allows the clip to play Wander Distance number of frames then randomly change directions.
        Pos : allows you to use the CONTROL parameter to set the position in a video mapped across the whole range of CV values!

Clear Clip (One Shot) : Sets the screen back to black after a One shot has been fired.
       On or Off

Rand Segments : Indicates how many pieces to split up a video clip. So if you had 100 frames, then a value of 25 would give you 4 random segment locations when you use the Random Clip Position with quantization on or use the Rnd Seg play mode.
       Range : 2 to 100

Rand Pos Quantized : Used with Random Clip Position to pick from the divided segment locations. If set to ‘Off’ any frame can be selected on random.
       On or Off

Wander Distance : The distance the clip will play in a direction in wander mode before randomly changing direction.
       Range : 1 to 15

Manual Step : Move one frame and wait for next ‘Step’ ACTION.
       On or Off

STATES :
       Reverse : Change the direction of the video playback in any mode

ACTIONS :

Previous/Next/Random/Last Clip will go to those clips.

Random Clip Position will go to a random frame, or a quantized frame depending on settings.

Reset / Trigger Clip will either reset in the playback position based on mode, or trigger a clip to start in the One shot modes.

Step : Advance a single frame and wait for next Step ACTION

Load Clip # will load that clip if present.

NOTES :

You can have 400 Frames of 640×480 video or 1600 frames of 320×240 video. The clips must be encoded as MJPEG A, One Field, No Interlace, and No audio. STRUCTURE can not mix clips of different resolutions.

COMMONLY ASKED QUESTIONS :

Q : I see a still image of my video clip, but it is not play or playing at the wrong speed
A : Check the position of the CV 1/X OFFSET knob. By default, that knob is tied to the CLIP Speed (in the PARAM menu) and might be affecting the video clip playback. It should be the 9 o’clock position to play the clip at normal speed.

Q : How do I use FFMPEG to convert video clips ?
A : Given MPEGStreamClip will not work on 64-bit OS X we needed to find another solution for Mac users. Right now, we are using the command line tool FFMPEG to convert videos. There are GUI interfaces to this tool, we’ll try to find one at some point to make this easier to do, but for now, here is instructions for running in the terminal.

I used ‘brew’ to install ffmpeg. You can get brew from https://brew.sh, then in a terminal type :
This was last tested on August 2022, on Mac OS 12.4 :


brew install ffmpeg

Then wait will it installs. Once it is installed you can use the following on the command line:

ffmpeg -i <input movie file> -c:v mjpeg -q:v 3 -an -vf scale=320:240,yadif=3:1 -frames:v 100 output.mov

-c:v mjpeg sets the output type, in this case motion jpeg

-q:v 3 sets the quality of the encoding. Using 1 is the highest setting, 3 seems to produce nice results, 32 is the max. Using 1 takes the longest time for sure

-an is the flag to NOT include audio, this is absolutely important to do

-vf has multiple settings included in it, let me go through them as well:

scale=320:240 sets the output side. This is not going to crop, it will basically resize everything to this size. I am sure there is likely some cropping commands and stuff, but that seems to be complicated. Instead you might edit your video elsewhere to get it into the cropped 4:3 size then convert with this. Also note you can do scale=640:480 

IMPORTANT: STRUCTURE can play clips in either 480 or 240 mode, not both at the same time. To select which size clips to use, go to the CLIPS section of the SYSTEM menu to make that change:

yadif=3:1 is for deinterlacing if it is present from what I can tell, so always include this. (previous version needed mcdeint=2:1 but that is no longer needed w/ffmpeg v5.1)

-frames:v 100 says just do 100 frames. If you leave this off, it will do ALL the frames. Remember that STRUCTURE has a max limit on number of frames for each mode, which is 400 for 640×480 video or 1600 for 320×240 video (basically both fill the same amount of RAM space)