Houdini 11 Nodes Compositing nodes

Loads image files into Houdini.

This COP loads image files into Houdini. Files without an animated time or frame in the filepath (i.e. default.pic, butterfly1.pic) are interpreted as single images. Otherwise, the last number in the filename (ignoring the extension) is considered to be the frame number of the image.

For numbered files, the frame range is automatically computed by searching the directory where the files found. Missing or bad frames will be replaced with black or neighboring frames, depending on the 'Missing Frames' parameter. Missing frames at the beginning or end of the sequence cannot be automatically detected, though bad frames can be replaced.

Using Proxy Images

Lower resolution images can be used in place of full-resolution images to speed up loading or to conserve space. Proxy filenames are entered in the 'Proxy' tab. The images files themselves should be an integer reduction of the image (1/2, 1/3, 1/4, etc). The main files do not need to exist in order to use proxy files (the largest proxy files will be used).

More than one proxy file can be entered. Halo will use the closest proxy image resolution not smaller than the current cook resolution (so if you were cooking at 1/3, and there were proxy images for ½ and ¼ resolution, the ½ resolution images would be loaded and scaled down, rather than up-scaling the 1/3 resolution images).

Note

Currently, the proxy images should be the same image format as the main images. This may change in the future.

Parameters

File

File

The path of the file(s) to load. The file is searched for using the HOUDINI_TEXTURE_PATH. Multiple files can be specified with $F, $I or a more complicated expressed for frame numbers.

File Node Naming

The File Node renames itself to match the current file settings. This parameter controls how the new name is built. User Defined or File Operator will disable this behavior. Changing the name manually will automatically switch this parameter to User Defined.

Detect Subframes

The character “.” is treated as a decimal, and sequences of images with fractional frame numbers are loaded. Each fractional frame is placed at the next available integer frame in the sequence (1,2,3...), rather than at subframes (1, 1.25, 1.5...).

File Size

Specifies the size of the file to load, either by at the natural resolution or a custom size.

Image Filter

When the file size is overridden, this specifies the image filter to use when scaling.

Pixel Aspect Ratio

Specifies the pixel aspect ratio of the image.

Flip Image

Flips the image vertically if on.

File Raster Depth

Selects how the raster depth is determined.

Natural Depth

The image file’s depth is used.

Project Depth

The depth specified in the Composite Project settings is used, overriding the file’s natural depth.

Specific Depth

The following Depth parameter selects the raster depth, overriding the file’s natural depth.

Depth

If the File Raster Depth parameter is set to Specific, this parameter sets the raster depth used for the files.

Override Frame Range

If off, the frame range is automatically determined by the lowest and highest frame numbers found in the file pattern. Otherwise the “File Range Start”, “File Range Length”, and “Shift to Start at Frame” parameters set the range.

Detect Frame Range

If Override Frame Range is on, you can do a one-time frame range detect of the sequence by pressing this button. It will put the range values into the following parameters.

Still Image

When checked, only the first image in the file range will be read and a still image will be created instead of a sequence.

Shift to Start at Frame

Specifies the frame where the sequence should start. If this number is different from the file range start, the sequence will be shifted appropriately.

File Range Start

Specifies the number of the first file where the sequence should start. For example, if the file name is file$F.tiff and the file range start is 15, the first file in the sequence will be file15.tiff. By default, this number is determined from the first file found matching the file name pattern, but it can be changed to create a sequence of a subset of the files.

File Range Length

Specifies the length of the sequence. By default, this number is the number of files matching the pattern. It can be changed to create a sequence of a subset of the files.

Missing Frames

If a frame is missing in the sequence, this parameter specifies how to handle it.

Missing Frames

For bad or missing frames, the File COP can either use a black frame or a neighboring frame.

Use Closest Frame

Searches forward and backward in the frames to find a substitution. The closest frame is used; in the event of a tie, the previous frame is taken.

Use Previous Frame

Searches backward from the missing frame to find a replacement.

Use Next Frame

Searches forward from the missing frame to find a replacement.

Use Black Frame

Bad and missing frames are replaced with a black frame.

Report Error

The File node errors when a bad or missing frame is found.

If on, a message is printed to the shell when a missing or bad frame is encountered (ie, “/img/img1/file1: Missing frame 1”).

Proxy

Enable Proxy Files

Enables the use of proxies, which are smaller versions of the full sized images. A proxy sequence should be identical to the original sequence, except for the resolution. When cooking the file COP at other resolutions than the proxy resolutions, the closest larger proxy sequence is used.

1/2, 1/4, 1/8 Res Proxy

Specifies the proxy sequence to use for 1/2, ¼ and 1/8 of the full resolution.

Custom Proxy

Allows you to specify other proxy resolutions and their proxy sequences.

Mask

A mask can be chosen to limit the effect of the operator to areas defined by the mask. The mask can be taken from the mask input (bottom input) or from the first input itself.

Effect Amount

If no mask is present, this blends the output with the input by a constant amount (0 = all input, 1 = all output).

If a mask is present, this amount multiplies the mask.

Operation Mask

Selects the mask plane to use as a mask from the mask input.

A mask can be a component of a plane or an entire plane. If a vector plane is supplied as a mask, its components are multiplied by the images' components.

Scalar Mask ('A', 'C.r')

            C.r = I.r * M
            C.g = I.g * M
            C.b = I.b * M
            
            
Vector Mask ('C')

            C.r = I.r * M.r
            C.g = I.g * M.g
            C.b = I.b * M.b
            
            
Resize Mask to Fit Image

If the mask image is a different resolution than the output image, turning on this parameter will scale the mask to the output image’s resolution.

If this node is changing constantly, and the mask is not, it is somewhat faster to put a Scale COP down to do the resize for the mask image. Otherwise, the scale will occur every time this node cooks.

Invert Mask

Inverts the mask so that all fully 'masked' portions become unmasked. This saves you from inserting an Invert COP after the node with the mask.

Sequence

This tab contains parameters which deal with the timing and frame range of the generated sequence.

Pre Extend

For sequences with a frame range, this determines how to show frames before the start frame.

Black Frames

Display black.

Cycle

Cycle the sequence, always playing it forward.

Mirror

Cycle the sequence, reversing the direction every cycle.

Hold

Hold the first frame indefinitely.

Hold N Frames

Hold the first frame for a certain number of frames; before that, show black frames.

Pre Hold

The number of frames to hold the first frame for, if 'Hold N Frames' is selected.

Post Extend

For sequences with a frame range, this determines how to show frames after the last frame.

Black Frames

Display black.

Cycle

Cycle the sequence, always playing it forward.

Mirror

Cycle the sequence, reversing the direction every cycle.

Hold

Hold the last frame indefinitely.

Hold N Frames

Hold the last frame for a certain number of frames; after that, show black frames.

Post Hold

The number of frames to hold the last frame for, if 'Hold N Frames' is selected.