Generates motion blur by blurring each pixel into a straight line, using the values from the motion vector channels (u and v channels) to determine the direction of the blur. You can create motion vectors using the VectorGenerator, MotionBlur2D, MotionBlur3D, or ScanlineRender nodes. Many third-party applications can also produce motion vector information as two-channel, floating point images that you can use with VectorBlur. If possible, you should unpremultiply these images.
You can also use the constant add u and add v values to add motion blur for camera movement and shake. Subtract the xy translation or camera rotation at the current frame from the same values at the next frame to get the correct values to use.
Connection Type |
Connection Name |
Function |
Input |
unnamed |
The image sequence to receive the blur effect. |
mask |
An optional image to use as a mask. By default, the blur is limited to the non-black areas of the mask. At first, the mask input appears as triangle on the right side of the node, but when you drag it, it turns into an arrow labeled mask. If you cannot see the mask input, ensure that the mask control is disabled or set to none. |
Control (UI) |
Knob (Scripting) |
Default Value |
Function |
VectorBlur Tab |
|||
channels |
channels |
none |
The effect is only applied to these channels. If you set this to something other than all or none, you can use the checkboxes on the right to select individual channels. |
uv channels |
uv |
none |
Sets the channel(s) to control the horizontal (u) and vertical (v) size of the blur vector. NOTE: If the uv values are read from a file, enable the Read node’s colorspace raw data checkbox. See Read. |
add u, v |
constant |
0,0 |
Sets a constant value to add to the uv channels values. NOTE: If the uv values are read from a file, this should be -.5 or -127/255. |
multiply |
scale |
1 |
Sets the value by which the u and v channels are multiplied. Set this to 0.5 for motion blur from a standard shutter. |
offset |
offset |
-0.5 |
Sets the shutter offset, causing the shutter to open at frame + offset. |
grow bbox |
grow_bbox |
0 |
Sets the number of pixels added to the outside edge of image. Set this manually for cropped images with non-zero uv channels. |
method |
method |
backward |
Sets the algorithm to use: • backward - a faster algorithm, but only useful if the motion vectors are continuous, with no abrupt changes at the edge of objects. • forward - draws a straight line for every pixel into an accumulation buffer. This method can be used when backward isn’t applicable, but is slow to calculate. |
alpha |
N/A |
disabled |
Enables the use of channel to the right. Disabling this checkbox is the same as setting the channel to none. |
alpha |
none |
The channel to use as a mask. By default, the effect is limited to the non-black areas of this channel. |
|
mask |
N/A |
disabled |
Enables the associated mask channel to the right. Disabling this checkbox is the same as setting the channel to none. |
maskChannelInput |
none |
The channel to use as the alpha channel. |
|
inject |
inject |
disabled |
Copies the mask input to the predefined mask.a channel. Injecting the mask allows you to use the same mask further downstream. |
invert |
invert_mask |
disabled |
Inverts the use of the mask channel, so that the effect is limited to the non-white areas of the mask. |
fringe |
fringe |
disabled |
Blurs the edges of the mask. |
mix |
mix |
1 |
Dissolves between the original image at 0 and the full effect at 1. |
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Using MotionBlur2D and VectorBlur to generate motion blur
Using MotionBlur3D and VectorBlur to generate motion blur
Using ScanlineRender and VectorBlur to add motion blur to particles