Video Engines

Max's video engine preference allows users to switch the backend video implementation for video objects application wide. Objects affected include jit.movie, jit.record, jit.playlist, and jit.matrixset. Still image loading may be affected by the video engine for jit.matrix and jit.gl.texture. Objects previously initialized are unaffected by a preference change, therefore open patches should be closed and reopened after switching the video engine. Individual jit.movie, jit.grab and jit.record objects may override the Video Engine application preference by typing @engine followed by the engine name argument, into the Max object box.

Platform Specifics

Max ships with support for two video engines on Mac platforms, avf (AVFoundation - the default) and viddll (Viddll - FFmpeg), and two on Windows, viddll (the default) and qt (DirectShow). The DirectShow based engine is named qt for historical reasons, and has limited functionality. Windows users wishing to extend the capabilities of the qt engine should follow the instructions here. The viddll engine utilizes the FFmpeg library to provide support for a wide variety of file formats and codecs. Both avf and viddll engines provide native playback support for HAP encoded video files.

On Windows platforms there should be no need to change the default video engine. On Mac there are pros and cons of the two supported engines. avf uses Apple's native video libraries and therefore is modern and efficient, but has less codec support and utilizes asynchronous seeking messages. viddll uses more system memory for playback, but supports more codecs and allows for instantaneous seeking by loading frames of video into memory via the cache_size attribute and loadram message.

Codec and Format Support

Common supported codecs for movie file reading with jit.movie and jit.playlist and file writing with jit.record and jit.matrixset:

• H264
• Photo-Jpeg
• ProRes (422 and 4444)
• Animation (viddll only)
• Many additional formats and codecs when using viddll

Supported image types for file reading with jit.matrix and jit.gl.texture:

• JPEG
• PNG
• TIFF
• GIF

jit.grab

At the time of this writing, the jit.grab object is unaffected by the video engine preference. On Mac jit.grab will use AVFoundation as the video digitizer, and on Windows DirectX is used. Additionally both platforms include native support for Blackmagic video input devices. See the Blackmagic tab of the jit.grab help file for more information.