Difference between revisions of "AVWizard"

Revision as of 18:22, 4 May 2008

Note: Due to a bug in the 0704 release, the numeric keys 0-9 on the Windows XP I/R remote may not set your output connector & resolution. If they do not, use the 0-9 keys on the keyboard or use another remote.

The AVWizard has two points of view:

• AVWizard user's point of view. This covers the aspects of the AVWizard that the end user will be interested in.
• AVWizard developer's point of view. This covers how to customise the AVWizard for your needs, like writing a separate backend.

Background

Consumer a/v gear, like DVD's, cable boxes and TV's, handle video differently than PC's and PC monitors. PC's and PC monitors exchange information about the resolution and capabilities of the monitors using EDID. With EDID, the PC figures out automatically what type of monitor and what type of video connector (VGA, DVI) is used. However, consumer a/v gear generally does not work like this. Instead the output resolution is generally set by a switch. The same video signal is output to all connectors at the same time.

This often leads to frustration when using a home theater PC. When you connect the PC to a TV, the PC still expects EDID information from the TV. Since most consumer TV's do not report EDID information correctly, the PC often incorrectly detects the active connector, or outputs the wrong resolution.

For most Linux users using a TV as a monitor, the solution has been to determine the correct settings for the TV using a modeline tool, and then manually editing the modeline of the Xfree86 module in Linux. This only has to be done once for each TV, but takes some effort and tweaking of Linux configuration files. Requiring a user to edit the Xfree86 modeline by hand is likely too complex for many users, so we decided to use a simpler manual configuration method for all video output devices.

Starting A/V Wizard

LinuxMCE is intended to act like a normal consumer a/v device, even though it is PC based. Therefore it does not use EDID to communicate to the TV or monitor. Instead, the user must manually specify the connector type and the resolution in the A/V wizard (unless you are using the default 640 x 480 VGA).

Initially

This wizard is started automatically the very first time the system boots; it does not automatically start after that.

Starting A/V Wizard from the LinuxMCE menu

The A/V wizard can be restarted at any time from the LinuxMCE menu by choosing Advanced--> Advanced--> A/V Wizard.

Restarting the AVWizard during bootup

Alternatively, the AV Wizard can be started during bootup. Either hold down the Shift key on the keyboard, or press the "A/V Menu" button on the remote to make the A/V wizard start. During bootup you should hear a series of escalating beeps to tell you when LinuxMCE is monitoring the Shift (and "A/V Menu") keys.

When you hear the descending beeps it means that you're too late; the bootup has already gone past the AV Wizard check and LinuxMCE has already started.

How A/V Wizard Starts

When A/V Wizard starts it always outputs 640x480 on the VGA connector. If you are not using a VGA connector, you will likely see a black screen when the A/V Wizard starts (even if you previously saw the Kubuntu boot splash). You will know that the A/V Wizard is running, however, because you will hear a series of beeps. If you then have video after hearing the beeps, proceed to complete the A/V Wizard. If not, see the next section.

What to do if A/V Wizard does not start

Press the number 1 through 5 on the keyboard (or the remote control) to switch to the active connector. Wait 15 seconds, and you will hear that same sequence of beeps telling you that A/V Wizard has now restarted. If you don't hear the beeps after 15 seconds, press the number for your connector again.

 Keys for choosing a connector:

1: DVI
2: VGA
3: Component
4: Composite
5: S-Video

If you hear the beeps but still don't see a picture, it's possible that the display you're using cannot handle 640x480. Press the number 6-9, or 0, as shown below, to select your resolution. Again, 15 seconds later, you should hear the beeps when the A/V Wizard is restarted. If you again then need to choose a connector (other than the default VGA), press the 1-5 key (as above) and wait until you hear the beeps again. Repeat as needed.

Keys for choosing a resolution:

6: 640x480
7: 1024x768
8: 720p
9: 1080i
0: 1080p

Once you have a picture you can proceed to complete the A/V Wizard. You can then resize your user interface to fit your screen, choose your audio outputs, and so on. Follow the AVWizard Step by Step instructions.

A/V Wizard makes the process a bit more complicated for PC users who may actually be using a PC monitor (instead of a TV) for video output. They are used to having EDID automatically detect and configure their monitor's output connector and resolution. Because EDID is turned off in LinuxMCE, however, these users will also have to manually set the output connector and resolution settings, as above.

That is the trade-off. We decided that to use a consumer TV with a home theater PC (and still have HD video) it would be simpler to use manual output type/resolution configuration for all video output, no matter whether a TV or a PC monitor is used. The alternative of requiring a user to edit the Xfree86 modeline by hand is likely too complex for many users.

AVWizard steps

For a detailed look at the individual screens and the different methods of connecting your display see AVWizard Step by Step

AVWizard is a 10 steps easy wizard which covers everything of basic configuration of your system.

After that will launch an OrbiterGen which will create an Orbiter corresponding to that tool.

The pages are:

• AV Welcome screen
• AV Resolution and Refresh screen
• AV Video Resolution counter
• AV UI Switcher
• AV Video Output
• AV Audio Connector
• AV Audio Volume
• AV Dolby Test
• AV DTS Test
• AV Final Selections

Running A/V Wizard from the Commandline

/usr/pluto/bin/AVWizard_Run.sh

Note that you should kill X and any process trying to reload it before running the wizard. You should only do this if your attempt to run it normally fails for whatever reason.

sudo -s /usr/pluto/bin/AVWizard_Run.sh

For developers

AVWizard is written in C++ using the libraries:

• SDL (SDL_image, SDL_rotozoom, etc.)
• libXML2
• network code

AVWizard executes these two steps:

• Generating screens of the AVWizard (in the /tmp folder as XML files)
• load modules one by one, depending of the needs of the (Main AVWizard).

Those two steps may be split in the future into two separate applications, making it more customisable. "Redundant code" may also then be reduced, such as defining object, save/load operations, and restore objects . The XML files keep only the display representations of the data. The factory creates the coresponding objects in a WizardWidget class which contains a tree of WizardWidgets that has as many child processes as are used.