Appendix A. The Video Panel

This chapter contains these sections:

Overview

This section includes “What the Video Panel Does,” “How to Use it: An Overview,” and “Help Conventions.”

What the Video Panel Does

The Video Panel displays the capabilities of video devices installed on your workstation and lets you adjust various settings for those devices.

Some things for which you can use the Video Panel:

  • controlling the signals coming from a camera or VCR hooked up to your workstation

  • adjusting the quality of the incoming and outgoing video signals

  • sending video and graphics to videotape

How to Use it: An Overview

The Video Panel lets you tell the workstation what kind of signal to expect from VCRs, video cameras, and other video equipment connected to it. If you have a VCR connected to your workstation, the signal coming from the VCR must be timed to match the signal the workstation expects. Use the Video Panel to adjust the signals and lock them together.

The Video Panel also contains a variety of “professional” settings that let you adjust settings for specific types of signals such as digital, component analog, or composite analog signals. Once you've set the workstation to expect a certain combination of elements, use the Pro menu to make chroma, gain, and other changes to the digital and analog signals.


Note: Whenever you see a reference to “save” in this documentation, it refers to saving video or graphics to a file on your system disk. When you “record” something you are recording video, graphics, or both to videotape.

The Video Panel works in conjunction with other media applications to let you combine audio and video clips into movies you can play on your workstation or record onto videotape.

For example, here's how the bundled media tools work together:

  • Use the Video Panel in conjunction with the Audio Panel to adjust and the video and audio input signals.

    Click the words Video Panel to open the Video Panel. Click the words Audio Panel to open the Audio Panel.

  • Use the Media Recorder tool to save incoming video to your system disk.


    Note: When using Media Recorder, there is no need to use the Video Panel to choose input devices—you only need to use it if you want to adjust settings such as the white balance (see “Setting the White Balance”).


  • Use Movie Maker to combine and edit the audio and video you've saved.

    If you wish to record the movie to a videotape, use the Video Panel and Audio Panel again at the end of the editing process to adjust the output signals for communication with the VCR. See “Sending Graphics to Video.”

  • Use Media Player to play your finished movie on your workstation.

Help Conventions

This document follows these conventions:

  • Click words that appear online as blue, italic text to bring up the definition of the term. For example, click: frame rate.

  • Red words indicate “launch links,” meaning that if you click them, they launch the tool that they name, for example: Media Recorder .

  • The symbol “>” between a menu names menu items indicates a path to a menu choice. For example, “File > Open” means “Open the File menu and choose Open.”

Adjusting the Video Signal

If you are using an O2 that came with an optional video board installed, see the O2video(7) man page for details on using the Video Panel. If you are using another type of system with an optional video board installed, see “Using the Video Panel With Optional Video Boards.”

Use the commands available from the menu bar to adjust the video signal. This section includes:

Using the File Menu Commands

The commands under the File menu let you save the settings or adjustments you have made on the Video Panel.

Save Current Setting 


Lets you save any adjustments you have made to the Video Panel controls. These adjustments apply to any video input or output.

Restore Setting 


Restores the setting saved previously using the “Save Current Setting” commands. Using this command, you can make temporary adjustments and restore your saved settings when you finish.

Restore Factory Settings 


Restores the factory settings.

Exit 

Closes the Video Panel.

Using the Device Menu

The Device menu lists any optional video equipment installed on your workstation. Choose the device you want the Video Panel settings to affect.

About the ProPanels

The Pro menu contains settings professional users may want for adjusting the video signal. The options available on the Pro Panels vary from system to system, depending on the hardware. See “Using the Video Panel With Optional Video Boards.”

See also “Using the Pro Panels” for more information about some of the adjustments you can make to the video signal.

Using the Video In and Video Out Utilities

The commands in the Utilities menu let you run applications that save incoming video to disk, record video to videotape, and launch the Audio Panel.

Live Video Input 


Lets you display video input in a window on your graphics monitor.

Live Video Output 


Lets you send graphics from your graphics monitor out to a TV or VCR.

Audio Control Panel 


Opens the Audio Panel so you can adjust the audio input, output, and rates.

Using the Video Panel With Optional Video Boards

The Video Panel is different for each type of optional video board:

  • If you are using a system with Indy Video, Indigo2 Video, or Galileo Video installed, read the following three sections for details specific to those boards.

  • If you are using any other system with any other type of optional video installed, refer to the manual that came with that video option for information that pertains to the Video Panel. You can also refer to the relevant man pages. For example, o2video(7).

    If you cannot locate your hardware manual, you should be able to access it at this Web site:

    http://techpubs.sgi.com/library/

    You can also check the Video Panel Update Web page for hardware-specific Video Panel information:

    http://www.sgi.com/Products/SGIHelp_Hub/Videopanel.html


Tip: “Using the Pro Panels” contains alphabetically listed descriptions on several of the types of controls you may have on your video panel. You may want to use it as reference, although it does not list every possible Video Panel control, as the controls change with each type of system and video board.


The Devices Region on Systems With Indy Video, Indigo2Video, or Galileo Video

The Devices region contains the controls that let you set up the software to accept a specific video input.

601 Option Genlock 


This button is available on workstations with Galileo Video 1.1. Put a checkmark in the box to improve signal quality if you are in genlock sync mode with CCIR timing.

Default In 

Specify whether the incoming signal is digital or analog.

Default Out 

Specify whether the outgoing signal is digital or analog.

Input Timing 

Select the signal timing to be the same as the video equipment. See NTSC, PAL, and CCIR-601.

Sync 

Determines the timing source for all video outputs. Synchronizes video output to an incoming signal or allows hardware to generate independent timing internally. See internal, slave, and genlock.

Genlock Src 

Sets the source of the timing signal. This is only valid when Sync is set to a mode of slave or genlock.

Inputs Region on Systems With Indy Video, Indigo2Video, or Galileo Video

The Inputs region lets you adjust the incoming signal.

Lock to VTR 

If you workstation is connected to a VCR, click the Lock to VTR button to stabilize the incoming signal. This helps improve picture quality.

Synchronizer Mode 


Locks the signals together and selects the input source. If you are using the Indy Cam or another video camera, you don't have to lock the signals.

Input Source 

Select the video signal that matches the signal being sent by the input source.

Outputs Region on Systems With Indy Video, Indigo2Video, or Galileo Video

The Outputs region lets you select the output format.

Lock to VTR 

Click the Lock to VTR button to stabilize video output. This helps improve picture quality.

Pixel Format 

Choose the pixel format for the component video signal. You don't have to choose a format if your equipment is composite or s-video. See the glossary for information about YUV and RGB.


Note: You'll notice that on systems with Indigo2 Video, there is no facility for choosing pixel format in the Outputs region of the panel. Indigo2 Video doesn't have component video features.


Saving Single Frames (Using Galileo and Indigo2Video boards)

To record individual video or graphics frames, a trigger input mechanism is included with the Galileo and Indigo2 video boards. Access to the trigger mechanism is provided through a line on the digital port. There are two ways to connect to the port:

  • Using the trigger-in BNC connector on the Galileo 601 digital video option box.

  • Using a trigger adapter cable to connect directly to the digital port without using the 601 option box. This cable is included with your video board option. If you didn't receive the trigger adapter cable, contact your sales or support representative for a free one.

Connect the trigger BNC connector to an interface box, such as the ALIX box from Videomedia, Inc., or an equivalent VLAN or IVAS interface box, or to a suitable edit controller. The output connector is usually labelled “GPIO.” Consult the documentation that came with the edit controller for information on how to use that product.

Use the Device Control Pro Panel in the Video Panel to select the controls for pulse polarity, external trigger line number, and the dominance field for the record.

If you aren't using a third-party application, use the shell command vidtomem -t to record the frames when the board gets the trigger signal from the edit controller.

Using a Bundled Camera

If you have a workstation that comes with a camera, you can set up to receive video input from the camera:

  1. Make sure the camera is plugged into the back of the workstation.

  2. On the Video Panel, use the Device Default Input menu button to select Camera Video.

Setting the White Balance

The white balance sets the natural range of colors. The balance is set in the factory, but you may want to adjust it to fit your own environment. To adjust the white balance click the White Balance button while holding a white piece of paper close to the camera lens.

Adjusting the Camera Video Display

To fine-tune features such as the color display, change the shutter speed, use the freeze frame control, or adjust the lighting and contrast, use the Camera Video Controls panel. From the Pro Menu choose “Camera Video” and rollover to the Camera Video Control panel. See “Using the Pro Panels” for a description of the fields in the Pro Panel.

Connecting a VCR or Video Camera

When connecting a VCR, VTR, or video camera to your workstation, you need to:

About Choosing a Cable

To connect a video device to your workstation, you should know what kind of signal your video device sends so that you can get the right kind of cable to connect it to your workstation. Four types of supported video signals are described here:

composite analog 


Most consumer VCRs and camcorders send composite signals. Connect this equipment to your workstation with RCA cables.

S-video (Y/C) 

Most high-end consumer VCRs and camcorders send and receive s-video signals. S-video carries the luminance (brightness) and chrominance (color) components of the picture on separate wires (Y and C). S-video connectors are also called Y/C connectors. Connect s-video equipment to your workstation using mini-DIN connectors. Most VCRs that use S-VHS and Hi-8mm tape feature s-video connectors.

component analog 


Used by professional equipment to produce higher-quality video. Connect component equipment to your workstation with BNC connectors.

component digital 


Used by professional equipment to produce higher-quality video. Connect component digital equipment to your workstation with BNC connectors.

You can buy BNC, mini-DIN, and RCA cables at most stores that sell camera, television, or computer equipment.

Making the Connection

Follow these steps when connecting a VCR, VTR, or video camera:

  1. Connect the video device to the proper port on your workstation.

    See your workstation owner's guide for instructions connecting video devices to your workstation. Alternatively, if your system has a video option board, see the owner's guide that came with the option board for information on how to connect video equipment to the option board.

  2. If it is not already open, click these red launch words: Video Panel to open the Video Panel now.

  3. Use the Default In menu button to choose the default input.

    For example, if you have connected a VCR, choose Analog Source as the default input.

  4. Use the appropriate Input Timing menu button to choose the timing standard used by your video device.

    If you are not sure which standard to choose, check the documentation that came with your video equipment. Also, you can click on these underlined words for definitions: NTSC, PAL, or CCIR.

    When you choose the timing, you need to use the menu button that corresponds to the type of video signal that represents your video device.

    See “About Choosing a Cable” for a list of video signal descriptions.

Displaying Video in a Window

You can display video from videotape to your workstation screen, you must have a camera or VCR connected to your workstation. See “Connecting a VCR or Video Camera.”

Use the videoin tool to display video in a window. Follow these steps:

  1. From the Utilities Menu choose “Live Video Input.”

    A window appears that displays the video input source you've specified.

  2. Resize the window by pulling the corners; zoom up and down by using the + and - keys.


Note: Media Recorder can be also used for displaying video. It is a tool with capturing capabilities and more of a user interface.


Sending Graphics to Video

To record graphics and audio from your workstation screen to videotape, you'll need:

  • a video tape recorder

  • (optional) a microphone to record audio (one comes standard with many workstations)

  • A 3.5mm stereo jack to RCA adaptor

  • two RCA-to-RCA cables (one for audio and one for video)

  • if you are recording to Hi8mm or S-VHS you will need a mini-DIN-to-mini-DIN cable as well.


Note: The connection instructions included in these steps may not be valid for all types of workstations. Refer to your workstation owner's guide for complete instructions on connecting video devices to your particular workstation. Owners guides can be found on the Web at:

http://techpubs.sgi.com/library/

Follow these steps:

  1. Connect the RCA-to-3.5mm adapter to Line Out on your workstation.

  2. Connect one end of the RCA cable to the adapter in Line Out.

  3. Connect the other end of the RCA cable to Line In on your VCR.

  4. Using the second RCA-to-RCA cable, connect Video Out on your workstation to Video In on your VCR.

  5. (optional) Use the http://techpubs.sgi.com/library/ Audio Panel to do the following:

    • To record audio through the microphone, click the Analog In panel to selecte it, then choose Selected > Input Source > Microphone.

    • Click the Monitor checkbox. A checkmark appears to indicate that the monitor is turned on. Audio from the workstation is mixed with audio input from the microphone and recorded to videotape.

  6. From the Utilities Menu in the Video Panel, select “Live Video Output.” A button labelled Live Video Output appears attached to your cursor.

  7. Place the button somewhere on the screen.

    A window with a white border appears in the upper left-hand corner of your screen.

  8. Click and hold down the left mouse button on the window outline. Drag it around the screen to enclose the area that you want to record. Or, if you want to record the entire screen, go to Step 9 instead.


    Note: You cannot resize the video output window.


  9. If you wish to record the entire screen, move the mouse over the Live Video Output button and hold down the right mouse button. Choose “Send Full Screen.”


    Note: 1280 x 960 lines of the 1280 x 1024 graphics screen are converted to video, so the bottom 64 lines are not recorded.


  10. Push the Record button on the VCR. To add audio, speak into the microphone connected to the VCR.


    Note: If you see dropped or duplicate frames, tearing, or motion artifacts, it may be that the graphics and video signals are not synchronized. For example, graphics may be running at 72Hz and video running at 50Hz. See “Synchronizing Graphics To Video.”


Synchronizing Graphics To Video

To record graphics or display video on a graphics monitor, the video and graphics signals must be generated at the same rate. When you synchronize the signals, you framelock the video and the graphics. Framelocking eliminates tearing and motion artifacts that occur if the video and graphics signals aren't synchronized.

Framelock the graphics and video signals using these commands in the Unix shell:

On Indy and Indigo2 XL, and O2 systems:

  • For PAL video type: setmon -Fg 50
    (This runs the graphics at 50Hz refresh mode.)

  • For the NTSC video standard, type: setmon -Fg 60
    This runs the graphics at 60Hz refresh mode.)

On Indigo and all Indigo2 graphics except XL:

  1. Connect the video source to the graphics board.

    • On Indigo, a BNC connector is provided on the back of the graphics board.

    • On Indigo2, you'll need a miniBNC to BNC adapter. Connect the miniBNC end of the adapter to the back of the graphics board. The adapter is included with your video board option. If you didn't receive an adapter, contact your local sales or support representative.

    • On Galileo Video, connect the BNC end of the adapter to the sync output connector on the breakout box. On all other systems, connect the BNC end of the adapter to the video source.

  2. Type the command for the video standard you are using.

    • For PAL, type setmon -Fi 50

    • For NTSC, type setmon - Fi 60

Now you are ready to display graphics synchronized to your video input or output graphics without motion artifacts.

Using the Commands To Output and Save Video Frames

Launch the tools described in this section by typing the name of the tool into a UNIX shell. Command line video tools include:

  • vintovout

    Sends videoout input to video output. There are three optional parameters:

    -n devicenum  

    The number of the video device to use. Use the command vlinfo to find the node number for the device.

    -o outputnodenum 


    The number of the output node to use. Use the command vlinfo to find the node number for the device.

    -I  

    Print the node and path numbers for use with the command line interface.

    -v 

    The number of the input node to use. Use the command vlinfo to find the node number for the device.

  • vlinfo

    Type vlinfo in a shell to see information about video devices.

  • videoout

    Displays a rectangular or near full-screen (1280 x 960) area of the screen in a video window. Move the cursor on top of the Live Video Output button and press the right mouse button to access a popup menu. This program is also available from the Utilities menu.

  • videoin

    Displays incoming video in a window. It also sends the incoming video out. This tool is also available from the Utilities menu.


    Note: For some video hardware configurations, the videoin and videoout windows cannot overlap.


  • vidtomem

    Saves frames from video to disk.

    Available on all video products.

  • memtovid

    Writes frames from a file to video.

Using the Pro Panels

Depending on what kind of video hardware you are using and what it supports, there will be different professional settings available on the Pro menu. This section contains alphabetically listed information on some of the different fields and settings available on the Pro Panels. Not all of the settings are available on all platforms.

AGC 

(Automatic Gain Control.) Move the Gain slider back and forth along the slider bar. The image changes to reflect the values you choose. To lock the gain control in place and have the device perform automatic gain control, put a checkmark in the AGC Enable box.

Anti-Dither 

Removes interference between frequency components generated by dithered graphics images and chrominance frequency components present in video signals. This is done with a notch filter in luminance. Recommended only for use when dithering causes a problem. Affects only composite and Y/C out.

Aperture 

Selects different aperture factors for luminance on composite and Y/C inputs. This adjustment affects the sharpness of the picture.

Bandpass 

Also affects sharpness. This filter can be programmed to different frequencies even when the chroma trap is bypassed.

Blank Level 

Sets the digital level for blanking in the custom table.

Black Level 

Sets the digital level for black in the custom table.

Bottom Flutter 

Available only in CCIR sampling. Compensates for horizontal phase jump on the selected line number.

B-Y Gain Fine 

Controls gain of B-Y component input in fine steps. Useful in tweaking gain or setting to a particular format. Active on Galileo Video only for Y/R-Y/B-Y input.

B-Y Gain Coarse 


Controls gain of B-Y component input in coarse steps. Useful in tweaking gain or setting to a particular format. Active on Galileo Video only for Y/R-Y/B-Y input.

Chroma AGC 

Chrominance automatic gain control speed for composite or Y/C.

Chroma Bandwidth 


Selects one of four low-pass filters in the decoder that determines chrominance bandwidth.

Chroma Delay 

Available only in CCIR sampling. Changes composite or Y/C chrominance delay without affecting luminance delay.

Chroma Gain 

Fine adjustment on chroma gain for composite and Y/C inputs.numerous

CLUT Load 

Loads default table or custom table. Default table gives standard output levels. Custom table allows user to specify nonstandard output levels as defined by the other controls in this panel.

Color Out Kill 

Makes composite or Y/C out monochrome, by shutting off color burst and chrominance.

Color Kill Threshold 


This setting controls the level at which burst amplitude decides if composite or Y/C input is color or monochrome when “Color Mode” is in Auto.

Color mode 

Gives you the following options:

  • Auto—Detects color/monochrome from burst.

  • Mono—Forces monochrome with chroma trap active.

  • Color—Forces color. Note that monochrome without a trap can be achieved by selecting S-Video input and not connecting C input. Works for composite and Y/C input.

Component 

Selects which component table is to be loaded with the custom setup.

Coring 

Selects different coring levels for luminance on composite and Y/C inputs.

C Gain 

Adjusts burst and chrominance output level of composite and Y/C simultaneously.

Filter Bypass 

Can be used to bypass the bandpass filter used to separet chrominance from luminance in the decoder. This filter is typically on for composite video inputs and off for SVideo inputs. It may be useful to turn off this filter when receiving a monochrome composite signal.

First Unblanked Line Out 


Sets the first unblanked line on all analog video outputs.

Fine H Offset 

Same effect as H Offset but with a narrow range. Resolution is pixel clock steps.

Genlock H-phase 


In genlock mode, provides a small range H-phase adjustment for all outputs. In slave lock mode, both H-phase and horizontal picture position are moved on composite and Y/C output. RGB and Y/R-Y/B-Y are unaffected in slave mode. No effect in stand-alone mode.

Horizontal Position 


Controls horizontal position of input picture. For composite and Y/C, resolution is 2 pixel steps. For Y/R-Y/B-Y input, resolution is 1 pixel step.

Hue 

Adjusts hue of composite or Y/C input.

Luma Delay 

This controls the relative alignment of luminance to chrominance.

Pixel Format 

Set expected peak white amplitude and setup or no setup on black for Y of Y/R-Y/B-Y input. The Beta format uses 714mV/setup. The SMPTE and EBU formats use 700mV/no setup.

Prefilter  

Enables an analog signal filter that usually results in a cleaner picture. Prefilter engages a high frequency boost that can be used for edge enhancement.

Quantization 

Sets the number of quantization levels. Set to maximum for no effect.

R-Y Gain Fine 

Controls gain of R-Y component input in fine steps. Useful in adjusting gain or setting to a particular format. Active on Galileo Video only for Y/R-Y/B-Y input.

R-Y Gain Coarse 


Controls gain of R-Y component input in coarse steps. Useful in tweaking gain or setting to a particular format. Active on Galileo Video only for Y/R-Y/B-Y input.

R-Y/B-Y Gain 

Sets the color difference gain factor in the custom table.

Subcarrier Frequency 


Fine adjustment of composite and Y/C output color subcarrier frequency. Total range +/- 450ppm. Affects output only in stand-alone mode.

Synchronizer Mode 


Should be used when video input and video output timing are not frequency locked. Removes small timing errors of video input. Can also be used to achieve frame synchronization.

SC-H Phase 

Adjusts sync-to-subcarrier phase with +/- 180 degree adjustment range.

Vertical Noise 

Selects the mode of vertical noise reduction.

V Offset and H Offset 


Active in genlock and internal mode. For composite and Y/C, output moves picture position relative to sync. For RGB and Y/R-Y/B-Y output, it is a wide range H-phase and V-phase control. It delays timing of the entire video signal (sync and picture) relative to selected timing reference such as genlock input.

White Level 

Sets the digital level for white in the custom table.

Y/C Gain 

Adjusts output level (sync, burst, luminance and chrominance) of composite and Y/C simultaneously.

Troubleshooting Problems With Video

Consult the list in this section if you encounter problems trying to display video on your workstation screen.

If video does not appear:

  • Make sure the camera or device is properly connected to the workstation and turned on.

  • Make sure you have selected the proper port for input for the input device. Refer to your workstation Owner's Guide.

  • If you have attached a video device, maker sure you are using the right kind of cable. Refer to “About Choosing a Cable” for more information.

If the video is of poor quality:

  • Make sure the NTSC or PAL and composite or S-video settings match those of your input source.

  • Try restoring the factory settings.

If you don't hear the audio input from a connected VCR:

  • Make sure one end of an audio cable is plugged into the video device and the other end is plugged into Line In on the back of your workstation.

  • Open the Audio Panel to make sure Monitor is on, the volume is properly adjusted, and that Selected > Input Source > Line In is chosen for the Analog In device panel (on Audio Panel).

If the video is black and white, you may have plugged in a composite camera, but selected S-video.

If black lines appear at the bottom of the screen, choose the NTSC or PAL standard format before running the application.

See the release notes for other potential problems and solutions.