SpeedSix.Speedo (Discreet Speedo Raptor)
PURPOSE
Slow motion using optical flow based motion estimation.
Please refer to the main documentation for full instructions on use.
INPUT CLIPS
1: Input Clip
: Select a clip to determine the motion 'flows'.
Speedo CONTROL PAGE
Process Now (Checkbox Default: Off)
When you have set up the paramters desired to retime the clip switch On before rendering. If you forget to do this the result will not be retimed.
Image (List Box Options: Full Frame | NTSC Fields | NTSC Fields (Rev) | PAL Fields | PAL Fields (Rev), Default: Full Frame)
This specifies whether the images in the input sequence are frame based or fields based. If they are fields based (interlaced), it also specifies the field order (based on the TV system type). Output images will be frame or field based to match the input image type as selected here.
Full Frame: Images are not interlaced. This is the case with film and progressive video formats (and is, of course, the One True and Proper Way).
NTSC Fields: Images are interlaced, with fields in the normal order for the NTSC television standard.
NTSC Field (Rev): Images are interlaced, with fields the other way around from the normal order for the NTSC television standard.
PAL Fields: Images are interlaced, with fields in the normal order for the PAL television standard.
PAL Fields (Rev): Images are interlaced, with fields the other way around from the normal order for the PAL television standard.
Note: "PAL" and NTSC" don't necessarily imply anything about the image resolution in this case.
Input Length (Number Min: 1, Max: 10000, Default: 25)
You must enter the input sequence length. This specifies the length of the input sequence you want to process. It can be less than or equal to the actual full length of the input sequence. Part of the reason for this control is that plugins cannot easily and reliably determine the length of an input sequence in many host systems.
Method (List Box Options: Times Longer | Times Shorter | Percent Longer | Percent Shorter | Percent of In | FPS Ratio | Final Length | VariSpeed, Default: Times Longer)
How you want to map output time to input time. Depending on which option you choose, other controls are presented that are appropriate. Note that "the length of the output" is measured in frames and will be rounded down to an integer number of frames (for obvious reasons!). Frame numbers within a sequence, however, start at zero and go up to the sequence length minus one. This is relevant particularly to VariSpeed.
Times Longer (Number Min: 1, Max: 100, Default: 5)
How many times longer than the input the output is to be. The output is to be a simple integer multiple of the length of the input. E.g. 5 times longer.
Times Shorter (Number Min: 1, Max: 100, Default: 5)
How many times shorter than the input the output is to be. The output is to be a 1 / n times the length of the input, where n is an integer. This is simply decimation - taking every nth frame. Except when motion blur is also applied.
Percent Longer (Number Min: 0.0, Max: 10000.0, Default: 0.0)
The output is to be this percent longer than the input. Note: 0% longer is the same length. The output will be ( control + 100.0 ) / 100.0 as long as the input.
Percent Shorter (Number Min: 0.0, Max: 10000.0, Default: 0.0)
The output is to be this percent shorter than the input. Note: 0% shorter is the same length. The output will be 100.0 / ( control + 100.0 ) as long as the input.
Percent Input Speed (Number Min: 1.0, Max: 10000.0, Default: 100.0)
The output is length is to be this percentage longer than the input. I.e. a straightforward scaling factor. Note: 100% is the same length as the input, 200% is twice as long, 50% is half as long.
Input FPS (Number Min: 1, Max: 1000, Default: 25)
Output FPS (Number Min: 1, Max: 1000, Default: 25)
You specify the frame rate of the input and the frame rate of the output. Together with the input length - which you always specify - this determines the output length. I.e. there will be ( FPSout / FPSin ) * InputLength frames in the output.
Expected Output Length (Text String)
The expected length of to output to be generated is automatically calculated when you choose the method of time change.
Plugin Status (Text String)
This gives you information on what Speedo Plugin is doing, and displays error messages if appropriate. Keep an eye on it as itis very useful to know what is going on especially if you have any problems.
Output Length (Number Min: 1, Max: 10000, Default: 80)
Enter the number of frames you want in the output clip.
Vari Speed Curve (Number Min: 0, Max: 10000, Default: 1)
Use the Output Length slider to set the desired number of output frames then use the keyframe editor (animated numeric value facility) of the host system to draw a graph (curve). The X axis of the graph is the output frame number. For any output frame number, the Y value at which a line normal to the X axis at the output frame number intersects the curve is used as the input frame number - which will generally be a number with a fractional part. If that sounds complicated, it isn't really! All you are doing is using a curve - any curve you can draw with the keyframer - to say where you want to be in the input for every output frame. This lets you do "ease-ins" and "ease-outs", to both speed up and slow down at different places in the input, and to go backwards, if you want. Note: If the input frame from the curve at any output frame is less than 0, it will be clamped to zero. If the input frame is ever greater than the highest input frame number (input length - 1), it will be clamped to that value.
Tuning Preset (List Box Options: Test | Fast | Good | Best, Default: Test)
This lets you choose the internal parameters used by Speedo's motion estimation algorithm in a very simple way. The motion estimator is subtle and sophisticated and its control parameters affect the results in ways that are often not obvious. This control lets you select sets of parameters which we have found are useful. In general, if the output is unsatisfactory with one of the choices you make here, try using a "higher" option from this list. You can adjust the internal parameters themselves on the Tuning Page if you wish.
Test: Use this when learning how to use Speedo and to see ifthe material you are working with is likely to give the desired result, If the result looks promising it may be worth tryingsome of the higher quality settings.
Fast: Not too slow, and perhaps good for many sequences.
Good: Somewhat slower, but should be good for most sequences.
Best: Very slow. Best reserved for "difficult cases".
Get Sequence Length (Pushbutton)
Set the sequence length to the length of the input clip. This will get the current sequence length in most cases. However if you do not want to process the whole clip, just test the first few frames for example, enter the desired lengthin the Input Length control box.
Motion CONTROL PAGE
Add Motion Blur (Checkbox Default: Off)
Turn on to activate the control set and add (or potentially add more) motion blur when calculating the output frames.
Shutter Angle (Number Min: 0.0, Max: 360.0, Default: 0.0)
We use the way film motion picture cameras work as the model for how we specify motion blur. These cameras have a disk which rotates 360 degrees in each frame period. The disk is placed so that it prevents light from reaching the film. A sector is cut from this disk. The size of this sector is measured in the number of degrees (angle) of circle that it uncovers. A 360 degree opening would be equivalent to having the shutter open for the whole frame period (this isn't possible in a real film camera - there has to be some time where the light is cut off in which to move the film to the next frame). A 0 degree opening would let no light through at all! In Speedo Plugin, though, 0 degrees is equivalent to no motion blur - a single sample is taken. Typical real world camera shutter angles are around 130 degrees. In a real camera, the shutter angle changes the film exposure as well as the amount of motion blur. Speedo does not simulate this.
Shutter Phase (Number Min: 0.0, Max: 360.0, Default: 0.0)
This controls when the shutter opens relative to the start of the frame period. It is also measured in degrees, as you'd expect. You can move the shutter opening partially into what would be the next frame period in Speedo, which, though harmless here, wouldn't be possible in a real camera.
Motion Samples (Number Min: 4, Max: 256, Default: 16)
This is the number of samples taken while the shutter is open. The samples are uniformly spaced in time over the shutter open interval, but the motion vectors at each pixel are perturbed randomly to an extent related to the time between samples to reduce potential artefacts due to sampling. If you have large shutter angles, you may want to increase this number from its default value. If you have small shutter angles, you may want to decrease it. (More samples means more computation, hence more time to calculate a result frame).
VariSpeed Length (Number Min: 1, Max: 10000, Default: 80)
Tuning CONTROL PAGE
Flow Resolution (List Box Options: Full | Half | Quarter, Default: Quarter)
Resolution at which to compute optical flow. The basic algorithm used by Speedo System is optical flow. This treats brightness in an image as it it were a sort of fluid (like water), and it tries to see in which direction the brightness has flowed out of each pixel from one input frame to the next. To capture big motions, it does this on a "pyramid" of image resolutions, starting from the very small and refining the estimates up to a fairly high resolution (potentially the full image resolution). The maximum image resolution it will use for this pyramid is called the Flow Resolution.
Note: This not the resolution at which your result images are computed!
Iterations (Number Min: 2, Max: 100, Default: 8)
The number of minimization iterations to do at each stage. Generally speaking, the more stages and the more iterations per stage, the better the motion estimate will get. Unfortunately, even this is not guaranteed, and it certainly isn't obvious what the best values would be from looking at an input sequence! (I.e. the smallest number of iterations and stages that gives a satisfactory result - in the least time).
Stages (Number Min: 1, Max: 24, Default: 2)
The number of stages over which to carry out the global minimization. The "stages" are designed so that early stages don't try to "pin down" the motion vectors absolutely. They are left a certain degree of freedom so they can be further corrected in later "stages". Each successive "stage" reduces this allowed latitude until at the last "stage" they are considered to be "pinned down".
Fix Brightness Shift (Checkbox Default: Off)
Try to compensate for overall brightness shifts between frames.
Process RGB (Checkbox Default: Off)
Off: Use the clip luminance to extimate the motion.
On:Use all 3 RGB channels in motion estimation. and do three times as much work!.
Show Vectors (List Box Options: None | Forward | Backward | Both, Default: None)
None: Motion vectors will not be drawn.
Forward: Draw forward motion vectors (from the earlier image of a pair to the later).
Backward: Draw backward motion vectors (from the later image of a pair to the earlier).
Both: Draw the forward and backward motion vectors.