Houdini 19.0 MPlay viewer

MPlay command line options

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Use mplay --help to display the list of options.


  • -default

  • -tools

  • -render

  • -flipbook

  • -viewer

  • -full

  • -minimal

Image options


Group the command line images into separate sequences, based on base name and extension.


Leave the images in the command line unsorted (in the order they appear).

-Z pad

Load only images that are padded to pad digits (or 0 for non-padded images only).


Load fractional frames: assume . is a decimal if it appears in filenames to the left of the frame number.


Disable negative frames: assume - is a separator, not a negative symbol, when it appears in filenames to the left of the frame number.

-z level

Load images zoomed to a certain percentage, where level is 12, 25, 33, 50, 66, 75 or 100.


Flip all images vertically.

-B file

Set the background image(s). This will automatically enable transparency and background images.


Load RGB color components only (no alpha).


Use an unlimited amount of memory for images.

-m N

Limit memory usage to N MB.

-w width

Images loaded from STDIN are width pixels wide.

-h height

Images loaded from STDIN are height pixels high.

-x aspect

Sets the pixel aspect ratio.

-X on|off

Enable or disable stretching to account for pixel ratio.

-S n

Load n images from STDIN in RGBA format.

-O startframe step

Load images from STDIN starting at startframe and skipping step frames.

-L lutfile

Sets lutfile as the lookup table for Cineon images.

-l w g iw

Sets the Cineon white point to w, the film gamma to g and the image white point iw.


Leave Cineon files in their natural 10 bit log space.

-d lutfile

Set the display LUT to lutfile.

-i lutfile

Set the inspect LUT to lutfile.


Always load images at 8-bit depth.

-G gamma

Sets the display gamma. For example, -G 2.2.

-j x1 y1 x2 y2

Select a sub-region of the image to load, using fractional values between 0 and 1. For example, -j 0.25 0.25 0.75 0.75 to load the center region.

-J x1 y1 x2 y2

Select a sub-region of the image to load, using pixels. For example, -J 20 10 320 200.

-E leftimg rightimg

Load two images as a stereo image pair.

-E file1 file2

Loads stereo image pairs. The first file specified should be the left image, and the second should be the right image.

Playback Options


Pre-cache all images at startup.

-f start end step

Sets the frame range (start to end) and frame step.


Startup in playback mode.

-P mode

Sets the playback mode to 'loop', 'once' or 'zigzag'.

-r fps

Set the frames per second for realtime play.


Turn on realtime play without specifying a rate.

-M mode

How to deal with missing frames, where mode is one of:


Show a black frame.


Show the closest available frame.

UI Options

-b s|d

Startup in single (s) or double (d) buffer mode. Single buffer provides faster playback speed (default).


Full image view mode; do not show any extra UI.


Disable tool tips.


Tell MPlay to listen on a socket for input images.


Tell MPlay to listen on a socket for flipbook images. Images rendered to the ip device will be displayed.


MPlay window stays on top (on Windows).

-V x y

Sets the viewport layout to x columns by y rows.

-e c|s|h|v|b|d [val]

Enables diffing with the mode set to:






Split horizontal (split at val, default 0.5)


Split vertical (split at val, default 0.5)


Blend (by val amount, default 0.5)


Highlight differences (uses val, default 0)

Audio Options

-a file

Load audio from file.

-A volume

Sets the volume scale (default 1).

-o fr sec

Aligns the animation frame fr to sec audio seconds.

-s on|off

Enable or disable the audio scrub sustain.

-W rate

Sets the audio scrub rate.

MPlay viewer