Andrew Hudson - Fedora™ Unleashed, 2008 edition

Timidity is a MIDI-to-WAV converter and player. If you are interested in MIDI and musical instruments, Timidity is a handy application; it handles karaoke files as well, displaying the words to accompany your efforts at singing.

You can use Fedora tools and applications to view movies and other video presentations on your PC. This section presents some TV and motion picture video software tools included with the Fedora distribution you received with this book.

To watch TV and video content on your PC, you must install a supported TV card or have a video/TV combo card installed. A complete list of TV and video cards supported by Fedora is athttp://www.exploits.org/v41/.

Freely available Linux support for TV display from video cards that have a TV-out jack is poor. That support must come from the X driver, not from a video device that Video4Linux supports with a device driver. Some of the combo TV-tuner/video display cards have support, including the Matrox Marvel, the Matrox Rainbow Runner G-Series, and the RivaTV cards. Many other combo cards lack support, although an independent developer might have hacked something together to support his own card. Your best course of action is to perform a thorough Internet search with Google.

Many of the TV-only PCI cards are supported. In Linux, however, they are supported by the video chipset they use, and not by the name some manufacturer has slapped on a generic board (the same board is typically sold by different manufacturers under different names). The most common chipset is the Brooktree Bt***series of chips; they are supported by the bttvdevice driver.

If you have a supported card in your computer, it should be detected during installation. If you add it later, the Kudzu hardware detection utility should detect it and configure it. You can always configure it by hand.

To determine what chipset your card has, use the lspci command to list the PCI device information, find the TV card listing, and look for the chipset that the card uses. For example, the lspci output for my computer shows the following:

# lspci

00:00.0 Host bridge: Advanced Micro Devices [AMD] AMD-760 [IGD4-1P] System Controller (rev 13)

00:01.0 PCI bridge: Advanced Micro Devices [AMD] AMD-760 [IGD4-1P] AGP Bridge

00:07.0 ISA bridge: VIA Technologies, Inc. VT82C686 [Apollo Super South] (rev 40)

00:07.1 IDE interface: VIA Technologies, Inc. VT82C586B PIPC Bus Master IDE (rev 06)

00:07.2 USB Controller: VIA Technologies, Inc. USB (rev 1a)

00:07.3 USB Controller: VIA Technologies, Inc. USB (rev 1a)

00:07.4 SMBus: VIA Technologies, Inc. VT82C686 [Apollo Super ACPI] (rev 40)

00:09.0 Multimedia audio controller: Ensoniq 5880 AudioPCI (rev 02)

00:0b.0 Multimedia video controller: Brooktree Corporation Bt878 Video Capture (rev 02)

00:0b.1 Multimedia controller: Brooktree Corporation Bt878 Audio Capture (rev 02)

00:0d.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL-8029(AS)

00:0f.0 FireWire (IEEE 1394): Texas Instruments TSB12LV23 IEEE-1394 Controller

00:11.0 Network controller: Standard Microsystems Corp [SMC] SMC2602W EZConnect

01:05.0 VGA compatible controller: nVidia Corporation NV15 [GeForce2 Ti] (rev a4)

Here, the lines listing the multimedia video controller and multimedia controller say that this TV board uses a Brooktree Bt878Video Capture chip and a Brooktree Bt878Audio Capture chip. This card uses the Bt878chipset. Your results will be different, depending on what card and chipset your computer has. This card happened to be an ATI All-in- Wonder VE (also known as ATI TV-Wonder). (The VE means Value Edition; hence, there is no TV-out connector and no radio chip on the card; what a value!) The name of the chipset says that the card uses the bttvdriver.

In the documentation directory is a file named CARDLIST,and in that file is the following entry, among others:

card=64 - ATI TV-Wonder VE

There are 105 cards listed, as well as 41 radio cards, including

card=0 - *** UNKNOWN/GENERIC ***

which is what you could have used had you not known the manufacturer's name for the card.

The file named Modules.conf, located in the same directory, offers the following example of information to place in the /etc/modules.conffile:

# i2c

alias char-major-89 i2c-dev

options i2c-core i2c_debug=1

options i2c-algo-bit bit_test=1

# bttv

alias char-major-81 videodev

alias char-major-81-0 bttv

options bttv card=2 radio=1

options tuner debug=1

All you need do is enter this information into /etc/modules.confand change the value for card=2to card=64to match your hardware. You can delete the reference to the radio card ( radio=2) because there isn't one and leave the other values alone. Then you must execute

# depmod -a

to rebuild the modules dependency list so that all the modules are loaded automatically. When finished, all you need do is execute

# modprobe bttv

and your TV card should be fully functional. All the correct modules will be automatically loaded every time you reboot. Fedora is clever enough to detect and configure a supported TV card that is present during installation.

Other useful documentation can be found in /usr/src/linux-2.6/Documentation/_video4linux. After you have identified a driver for a device, it does not hurt to look at the source code for it because so little formal documentation exists for many drivers; much of it is in the source code comments.

The development of support for TV cards in Linux has coalesced under the Video4Linux project. The Video4Linux software provides support for video capture, radio, and teletext devices in Fedora.

Fedora recognizes a variety of video formats. The formats created by the MPEG group, Apple, and Microsoft dominate, however. At the heart of video formats are the codecs — the encoders and decoders of the video and audio information. These codecs are typically proprietary, but free codecs do exist. Here is a list of the most common video formats and their associated file extensions:

► .mpeg—The MPEG video format; also known as .mpg

► .qt— The QuickTime video format from Apple

► .mov— Another QuickTime video format

► .avi— The Windows audio visual format

An RPM that provides a Divx codec for Linux can be found at http://www.freshrpms.net/. Divx is a patented MPEG-4 video codec that is the most widely used codec of its type. It allows for compression of MPEG-2 video by a factor of 8. See http://www.divx. com/ for more information.

The GetCodecs application is a Python script with a GUI interface that downloads, installs, and configures your Fedora system with multimedia codecs not provided by Fedora, such as MP3, Divx, and DVD codecs. The script can be obtained from http://sourceforge.net/projects/getcodecs/.

If you need to convert video from one format to another, you use encoder applications called grabbers. These applications take raw video data from a video device such as a camera or TV card, and convert it to one of the standard MPEG formats or to a still image format, such as JPEG or GIF. Fedora does not supply any encoder applications (other than ppmtompeg,which encodes MPEG-1 video), but you can find them at http://www.freshrpms.net/ or another online source (see the "Reference" section at the end of this chapter).