v4l-utils
---------

Linux utilities and libraries to handle media devices (TV devices,
capture devices, radio devices, remote controllers).

You can always find the latest development v4l-utils in the git repo:
	http://git.linuxtv.org/v4l-utils.git

Those utilities follow the latest Linux Kernel media API, as documented
at:
	http://linuxtv.org/downloads/v4l-dvb-apis/

Any questions/remarks/patches can be sent to the linux-media mailinglist.
See https://linuxtv.org/lists.php for more information about the mailinglist.

There is also a wiki page for the v4l-utils:

	https://linuxtv.org/wiki/index.php/V4l-utils


--------
Building
--------

A number of packages is required to fully build v4l-utils. The first
step is to install those packages. The package names are different on
each distro.

On Debian and derivated distributions, you need to install the following
packages with apt-get or aptitude:
    debhelper dh-autoreconf autotools-dev autoconf-archive doxygen graphviz
    libasound2-dev libtool libjpeg-dev qtbase5-dev qt5-default
    libqt5opengl5-dev libudev-dev libx11-dev pkg-config udev make gcc git


On Fedora, the package list for a minimal install with dnf or yum is:
	git automake autoconf libtool make gcc gcc-c++ which perl gettext-devel

(git is only requiried if you're cloning from the main git repository at
 linuxtv.org).

And, to be able to compile it with all usual functionality with qt5,
you'll need also:
	alsa-lib-devel doxygen libjpeg-turbo-devel qt5-qtbase-devel
	libudev-devel mesa-libGLU-devel


After downloading and installing the needed packages, you should run:

	./bootstrap.sh
	./configure
	make

If ./configure exit with some errors try:

	autoreconf -i --force
	./configure

And, to install on your system:
	sudo make install

Optional features
^^^^^^^^^^^^^^^^^

Please notice that there's an extra feature to add an extra table to
decode Japanese DVB tables via iconv. This is meant to be used when
the iconv itself doesn't come with the ARIB-STD-B24 and EN300-468-TAB00
tables.

That requires not only the gconv package, but it also needs to be manually
enabled with:
	--enable-gconv

----------
versioning
----------

The v4l-utils doesn't quite follow the release versioning defined
at semver.org.

Instead, since version 1.0, it uses:

	MAJOR.MINOR.PATCH

Where:

	MINOR - an odd number means a development version. When
		the development is closed, we release an even
		numbered version and start a newer odd version;

	MAJOR - It is incremented when MINOR number starts to be
		too big. The last change occurred from 0.9.x to 1.0.

	All numbers start with 0.

All versions have their own tags, except for the current
deveopment version (with uses the master branch at the git tree).

The PATCH meaning actually depends if the version is stable
or developent.

For even MAJOR.MINOR versions (1.0, 1.2, 1.4, 1.6, ...)

	PATCH is incremented when just bug fixes are added;

For odd MAJOR.MINOR versions (1.1, 1.3, 1.5, 1.7, ...)
	PATCH is incremented for release candidate versions.

API/ABI stability:
-----------------

There should not have any API/ABI changes when PATCH is incremented.

When MAJOR and/or MINOR are incremented, the API/ABI for the
libraries might change, although we do all the efforts for not
doing it, except when inevitable.

The TODO files should specify the events that will generate
API/ABI breaks.

---------------
media libraries
---------------

There are currently three media libraries defined at /lib directory,
meant to be used internally and by other applications.

libv4l
------

This library is meant to be used by applications that need to
talk with V4L2 devices (webcams, analog TV, stream grabbers).

It can be found on the following directories:
	lib/libv4l1
	lib/libv4l2
	lib/libv4l-mplane
	lib/libv4lconvert

See README.libv4l for more information on libv4l.

The libv4l is released under the GNU Lesser General Public License.

libdvbv5
--------

This library is meant to be used by digital TV applications that
need to talk with media hardware.

Full documentation is provided via Doxygen. It can be built,
after configuring the package, with:
	$ make doxygen-run

It is possible to generate documentation in html, man pages and pdf
formats.

The documentation is also available via web, at:
	http://linuxtv.org/docs/libdvbv5/

It can be found on the following directory:
	lib/libdvbv5

The libdvbv5 is released under GPL version 2.


libv4l2rds
----------

This library provides support for RDS radio applications.

It can be found on the following directory:
	lib/libv4l2rds

The libv4l is released under the GNU Lesser General Public License.

---------
Utilities
---------

The utilities are stored under /util directory.

The (for now for v4l-utils private use only) libv4l2util library is
released under the GNU Lesser General Public License, all other code is
released under the GNU General Public License.

v4l-utils includes the following utilities:

decode_tm6000:
Decodes tm6000 proprietary format streams.
Installed by make install under <prefix>/bin.

ir-keytable:
Dump, Load or Modify ir receiver input tables.
The ir tables for remotes which are known by the kernel
(and loaded by default depending on dvb card type) can be found
under utils/keytable/keycodes.
v4l-keytable does not get installed by make install.

ir-ctl:
A swiss-knife tool to handle raw IR and to set lirc options

qv4l2:
QT v4l2 control panel application.
Installed by make install under <prefix>/bin.

rds-saa6588:
Poll i2c RDS receiver [Philips saa6588].
rds-saa6588 does not get installed by make install.

v4l2-compliance:
Tool to test v4l2 API compliance of drivers.
Installed by make install under <prefix>/bin.

v4l2-ctl:
Tool to control v4l2 controls from the cmdline.
Installed by make install under <prefix>/bin.

v4l2-dbg:
Tool to directly get and set registers of v4l2 devices,
this requires a kernel >= 2.6.29 with the ADV_DEBUG option
enabled. This tool can only be used by root and is meant
for development purposes only!
Installed by make install under <prefix>/sbin.

v4l2-sysfs-path:
FIXME add description.
Installed by make install under <prefix>/bin.

xc3028-firmware:
Xceive XC2028/3028 tuner module firmware manipulation tool.
xc3028-firmware does not get installed by make install.

-------------------
Syncing with Kernel
-------------------

There are a number of files on this package that depends on the Linux Kernel.

In order to make easier to keep it in sync, there's a target on this
package to do the synchronism.

For the sync to work, you need to run it on with 64 bits userspace and
be sure that glibc has the development package for 32 bits.

For Fedora, this is provided via this package: glibc-devel.i686

There are some steps required:

step 1) at the Kernel git tree:

We need to sanitize the headers to be installed. To do that, you should
run

	$ make headers_install INSTALL_HDR_PATH=usr/

This will create the dir "usr/" inside the Kernel tree.

step 2)

Be sure that you have installed both glibc development packages for
32 and 64 bits, as otherwise the next step will fail.

step 3) at v4l-utils tree:

	$ ./sync-with-kernel.sh location/of/the/kernel/tree

Alternatively, steps 1 to 3 can be replaced with:

KERNEL_DIR=location/of/the/kernel/tree && (cd $KERNEL_DIR && make headers_install INSTALL_HDR_PATH=usr/) && ./sync-with-kernel.sh $KERNEL_DIR

step 4)

Remove the usr/ from the Kernel tree.