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Performance Options

When you select "options" from the Performance Menu, the performance options dialog box appears. This box contains three different tabs:


MIDI / FreeFrame

This tab allows you to configure your MIDI settings, including the device to use for MIDI input, and which channels to listen to.

MIDI device

This pull down menu allows you to choose the midi device you want midivid to respond to. If you only have one midi device (usually your sound card) it will be the only choice available. If you have a midi loopback device installed, it will also show up here.

Active MIDI channels

This is where you decide wich channel(s) MidiVid responds to. You can activate up to 16 midi channels. Click on the channel(s) you want to activate and it will turn highlight to a lighter shade of grey. When you have finished setting the performance Options click ok. The dialog box will disappear and your new options will be in effect. If you click on cancel or hit the escape key while the performance options box is open, the dialog box will disappear and midvid will reset to the previous performance settings.

Play & hold mode checkbox

This is a general sustain mode. Triggered notes remain active until retriggered or until the space bar is hit. Hitting the space bar is the equivalent of sending an all notes off command. This command (space bar) is also useful for stuck notes.

FreeFrame Plugin Path

This is the folder that MidiVid GPU will check on startup for FreeFrame plugins. By default, it's a folder in the MidiVid GPU folder called "FreeFrame", but you can change it to anything you like. Check the section on FreeFrame Plugins for more information.



This tab allows you to choose which video card and display resolution to run your performance in, and a couple other relevant options.

The frame buffer panel

This is the area where you make general video display settings for your performance. The following options are available:

Video card

Windows lets you use multiple video cards. This setting allows you to decide the video card to use when in performance mode. The default setting is your primary display driver and will be the only setting available if you only have one card installed.


Here you may choose a resolution to run your performance at when in full screen. Choose the resolution that works best for your application. For video projection we recommend 640x480 or 800x600. Some projectors will handle higher resolutions, but the amount of memory that the video card has to manipulate grows significantly as resolution increases, which may lower your frame rate if you are doing a lot of video processing or effects.

Bit Depth

This option lets you choose which color resolution to use when in full screen. 32bpp (32 bits per pixel) is reccommended because this gives excellent color precision, good transparency effects, and is still very fast.

Refresh Rate

Here you choose the refresh rate of the video mode you've selected. For projection or TV output, use the number that corresponds to your television or video standard. 60hz in North America, 50hz in Europe.

Work Buffers

Midivid allows you to create and use up to four additional frame buffers for the purpose of compositing effects. Any effect can be drawn to one of these work buffers instead of the screen, and any work buffer can be used as the video source for any other effect. For example, you could play an AVI file to a work buffer, then Radial Blur it, HSV Shift it, then use the Cubist plugin to put the result on the sides of a cube spinning in front of another AVI with different effects applied and playing on the main screen. See the Notes List for how to change which buffer a note is assigned to.

Resizing Mechanism

3D video cards are very powerful, but come with some limitations in order to attain the speed they do. Most 3D video cards prefer source material to be in dimensions that are powers of two (2, 4, 8, 16, 32, 64, 128, 256, 512, 1024). Most recent video cards support data that's not a power of two size, but some of these apply certain restrictions. For example, the NVidia GeForce FX 5200 that I have won't tile an image across a single polygon unless it's a power of two in both dimensions.

Rather than force you to keep track of these rules, or worse, resize all your content, MidiVid will automatically use the video hardware to resize things for you as necessary. If a plugin requests content that can be tiled, MidiVid will scale the source material to a power of two size based on the choice you make in this box. 640x480 video could be sized to either 512x512 (nearest size), or 1024x512 (next larger size). Choosing "Conserve memory" will sacrifice a small amount of quality in order to conserve memory and memory transfer rate. Choosing "Preserve Quality" will ensure that the video is never reduced in size, but will incur a small performance cost.

For most users the "Conserve memory" option will be fine, however if you're a purist, you may wish to use "Preserve quality".



This tab allows you to specify which, if any, capture devices should be available as data sources for the performance, and allows you to configure them. Any installed capture devices will show up here. If a device is capable of producing a data format that MidiVid understands, a small box will appear next to the device name, like the one next to "Dazzle DVC90" in the image at right. You will also see the current capture format and status of the device. Clicking inside the box to the left of the device name will activate the capture device. A data source for the device will be available from the source chooser as long as the device is running.

When you select a device name from the list, the "Select Capture Format" button will be enabled. Clicking the button will bring up a list of capture formats supported by the device, like the one shown to the right.

MidiVid supports YUY2, YUYV, and UYVY, as well as RGB modes. It is possible that I will expand support to include additional modes, however the chosen capture modes can usually be converted to RGB by modern video cards, and therefore require very little CPU overhead to use.

Many capture devices have more than one input to choose from as well. Pressing the "Select Capture Input" button will let you choose which capture input to use.



MidiVid GPU incorporates a Video Sampler. This panel lets you configure the size, format, and length of the samples your performance can use. Click the "Create New Sample" button, and you'll be presented with a dialog which allows you to choose from a number of different video sizes, frame rates, and 16 or 32 bit images. You can also specify the length of the sample, in video frames. Along the bottom of this dialog box you'll see a display indicating how much memory this sample will consume. These samples are stored in your main memory, so they can be quite large, but knowledge is power - an 8 second, 640x480 32bit sample at 30fps comsumes about 300 Mb. It adds up quickly.

Once you've created a sample, you can use the "Sample Source" plugin to acquire data from any MidiVid source plugin, including capture devices or the current display. You will also see the the sample itself show up as a video source, meaning that you can play it through all the available effect plugins.

Add the ability to right-click and edit / delete existing samples



MidiVid GPU now includes a powerful LFO (low frequency oscillator) bank. An LFO is essentially a 'number generator' that produces a constantly changing number based on parameters like minimum value, maximum value, rate of change, waveform style, and so on. The output of an LFO can be connected to a plugin through the Knob Shelf.

This panel lets you configure the various parameters that affect each of the 100 available LFOs. Experiment with the various settings and you'll see a preview of the result in the displayed graph. For more 'realtime' control, you can assign an LFO to a parameter and edit it while the plugin is running. This is most easily accomplished by using either a MIDI keyboard, or 'Play & Hold' mode.

Note that the number editing fields support both mouse and keyboard - pressing arrow keys, PgUp, PgDn, or clicking and dragging within the number box will change the value.

Important note!
When you have set all your options, you should save your performance.

MidiVid GPU Version 1.0
Copyright (c) 2005 Jason Dorie and VUTAG
Generated on: Sun Jan 25 23:45:41 2009