'VGA Device Output' node and MK-Mediaplayer (Alpha 3)



--- Please print this documentation: you just might need it! ---




NOTE PLEASE:
You use this software at your own risk! Although I don't expect it to damage your PC, videocard or Monitor, I cannot guarantee this!

Please read this entire document before you attempt to install the VGA Device output node if you want to be optimally prepared. If you just want to get it going fast and easy, you should at least read this.

Hardware supporting the 'VGA Device Output' node (as far as is known):

Notes:

Features:

Known limitations:

Configuring your system for use with the video node:


If you want trouble-free install and use, you should adhere to the items as listed here:
If you are prepared to do some testing and/or you have one not entirely supported card, there are some precautions you might need to take. Please take notice of the items in the list below.

Node Installation / De-installation:


Install the VGA Device output node (file 'VGAdevice.media_addon') by dragging it in the 'home/config/add-ons/media' folder. If this folder doesn't exist on your system, just create it. De-installing means you just have to remove the file from this folder.
Using the home hierarchy makes it easy to overcome trouble because BeOS first checks (during boot) if there are 'user-addons' that should be loaded for a service. If not, it loads it's own add-ons (if any). You can select if the add-on should be loaded by hitting the spacebar as soon as the BeOS 'icons' screen appears. If you select disable user addons the system will not load the VGA Device output node. If you don't do anything, the system will load it.

Note: This might turn out to be handy if you run into trouble upon testing the node, or if you are 'tweaking' driver settings files...

You have to restart the Media services in order to apply a new (or old) configuration.

Using the video node (results):


Since the video (and audio) is played back through codecs, the codec behaviour influences what results you see. Because codecs vary in their flexibility (and correctness) per 'BeOS version', it makes sense to outline the results 'per OS'. Configuring the node's properties however is the same on all BeOS versions, so that doesn't need to be split-up here.

If you want to see some debug messages from the node just open a Terminal window and start the Media preferences application from there. If you hit the 'Restart Media Services' button in the preferences app, all debug messages will be sent to the terminal's window.


General (node properties).

In the 'Media' preferences panel, select the item 'Video Settings' in the left part of the Media window. Here you will find the default nodes that will be used for video input and video output. You should select the 'VGA Decice Output' node as being the video output if you want to playback on a seperate graphicscard. Selecting 'Video Window Consumer' will playback video in a scalable window on your desktop, while 'Default DV Output' should playback to a firewire camcorder (for instance).

Now, Find the item 'VGA Device Output' in the left part of the Media window and select it. On the right side of the Media window you'll see the current graphics card that's selected for output in this node. If you have more than two graphics cards in your system, you'll (probably) be able to switch between them: select the one you want to use.

Go back to the 'Video Settings' item in the Media window, and hit the 'Restart Media Services' button for the changes to take effect. After the restart finishes you'll be using the graphics card you selected for video, if you also selected the 'VGA Device Output' node.

Note please:
If the 'VGA Output Device' isn't visible in your Media preferences window, try to restart the media services. If it's still not there, the node doesn't register because it can't find useable free graphics cards in your system.


Supported input colorspaces (driver properties).

The node supports hardware video overlay using the B_YCbCr422 colorspace, and it supports B_RGB32 and B_RGBA32 using the hardware acceleration engine. The actual spaces the node will support depends on the functions actually implemented in the graphics driver (and graphics card) in use. All (known) BeOS (and derivates) graphicsdrivers support hardware overlay at best, except for the Haiku unified nVidia driver: this one also supports scaled video playback using the acceleration engine.

This means the following situations can occur: Notes:

R5 (Codecs)

On R5 most (or all?) codecs only support RGB modes on their producer node outputs. Most (or all?) (other) codecs also determine their bytes_per_row setting themselves, they don't support custom settings requested by a consumer node. For these reasons you will not be able to enjoy much video using the VGA Device Output node. If you install the 3ivX D4 4.5 codec however, you can watch DivX/Xvid correctly with both overlay (B_YCbCr422) and accelerated (B_RGB(A)32) output.

Note please:


Dano (Codecs)

On Dano most (?) codecs support both RGB modes and B_YCbCr422 mode on their producer node outputs. Most (?) codecs are also flexible in their compatibility regarding bytes_per_row settings, they offer a wildcard here (as it should be in my opinion!!). For these reasons you will be able to enjoy much video using the VGA Device Output node. If you additionally install the 3ivX D4 4.5 codec, you can also watch DivX/Xvid correctly with both overlay (B_YCbCr422) and accelerated (B_RGB(A)32) output.

Note please:


Zeta 1.2 beta (Codecs)

On Zeta most (?) codecs support both RGB modes and B_YCbCr422 mode on their producer node outputs. Some (?) codecs are also (still?) flexible in their compatibility regarding bytes_per_row settings, they offer a wildcard here (as it should be in my opinion!!). For these reasons you will be able to enjoy more video than on R5, but less than on Dano, using the VGA Device Output node. If you additionally install the 3ivX D4 4.5 codec and remove the (updated?) version Yellowtab installed, you can probably also watch DivX/Xvid correctly with both overlay (B_YCbCr422) and accelerated (B_RGB(A)32) output. Yellowtab's new(er) DivX/Xvid codec is just as fixed as the old cinepak codec, which they also still use.

Note please:


Haiku (Codecs)

On Haiku I can't actually see video yet using a node (using a build of 25 april 2006). However, there is some good news: All in all I'm very pleased with the results sofar: Would be cool though if it would actually be useable soon.. ;-)


MK-MediaPlayer

MK-MediaPlayer is a relatively simple application that runs on R5, Dano, Zeta 1.2 and Haiku; independant of the 'VGA Device Output' node. It has a simple user interface. Here's what it does: If you want to see some debug messages, just run MK_MediaPlayer from a Terminal command line. All related messages will be sent to the terminal's window then.


Rudolf Cornelissen.

(Page last updated on April 27, 2006)