Avicap User Documentation

to Avifile Homepage to Avicap Homepage

docu by: Alexander Rawass (alexannika@users.sourceforge.net)
if anyone can write a better documentation - please do it and tell me

Avicap is a capturing tool for video4linux that allows to record in realtime with various (DivX-)codecs.
Avicap also contains a programmable timertable, so that Avicap can be used like a VCR/PVR.
Avicap also allows to automatically shutdown/poweroff and resume/poweron your computer in-between programmed recordings.
Avicap also displays EPG (Electronic Program Guide) Information, that can highlight or block programs to the regexp of your choice.

Avicap is part of the avifile library

Sections in this documentations:

Features:

video4linux grabber interface
Qt GUI, full control of recordings via GUI
lot of different codecs for encoding:

windows dlls (including DivX3.11a, Huffyuv etc)
XVid native
Divx4Linux native
FFMpeg native

encoding thread buffers frames when system load is high
perfect A/V-sync
automatically segments recording at given size
you can change saturation/brightness/etc while recording
not hundreds of commandline options ;-))
no Digital UnRights Management ;-)
distributed under the GPL/LGPL license - it's Free Software!
programmable timertable
EPG Electronic Program Guide
it can highlight or block programs by regexp
password lock to enforce blocking of programs
shutdown & resume option to shutdown/poweroff and resume/poweron your computer between recordings
Directory Pool, to use all your free space on all partitions automatically

Usage:

start avicap with 'avicap'

A window will come up, showing the currently selected channel (if you've used a v4l app before), or with noise, because no channel has been set yet.
Best to go to the Configuration Dialog and set the correct settings for your video device.

When you click the right mouse button, a menu will pop up with those entries:

Configuration
there you can select your video device, input, color space and grabbing size
Xawtv station
If you have a valid xawtv configuration file with channels set, then Avicap will use that file to show you a channel list in this menu
Picture Properties
changes saturation,brightness,etc
Timertable
opens the window to show the programmable timertable
Electronic Program Guide
opens up the window of the EPG Electronic Program Guide
the timertable window will also be opened
Capture AVI
capture an avi manually
a new window will come up, click 'start' to start the recording

If you start avicap with 'avicap -timer' , the timertable window will automatically open and start the timer to wait for pending recordings.

Performance?

My system is an Athlon550 with TNT2pro graphics card, running SuSE8.1 with kernel-2.4.18 with apm enabled, I am using nvidia's proprietary drivers (shame on me!).
I've got 384MB ram and a bttv-compatible TV-card, I am using the v4l/bttv driver in the kernel.
My harddisks are set to Ultra-DMA 2 mode, they can write 30MB/sec and read 20MB/sec.
My Motherboard is a Asus K7M which has got a 'RTC Alarm Resume from Soft-off'.

I record at 384x288 pixel, in YV12 or RGB24 color mode, 25fps PAL.
My preferred codec at the moment is native XVid, at 3Mbit/sec for perfect quality, with halfpel interpol. and lum. masking turned on

I have to nice avicap to a lower priority (-15) to not get any framedrops in recording (whatever I do else with my system), the recording takes up 65-75% of my CPU time - great!

Avicap can record stable in the background without any framedrops, I can read/write Emails in kmail and surf the net with galeon without suffering from framedrops.

If I also nice up gcc, I can also compile source code (nice -15 make).

I can also watch other avis with mplayer while I am recording, but I have to nice mplayer up, so mplayer gets it's framedrops - but NO framedrops in the recording, which is more important.

Hey, that's quite a good performance for a nowadays slow 550MHz CPU - thanks especially to the xvid team for their codec :-)))

Can anyone tell me which processor I need to record with xvid/divx/ffmpeg in PAL-fullscreen (786x576) in superb quality - cause that's the only thing I'll need a newer/faster CPU for? :-)))

Plans for the future:

Fullscreen/Maximize mode with xvideo overlay
record while zapping through channels

Screenshots

Screenshot of the programmable Timertable
There, you can see my list of recordings for the next time.
The current recording is highlighted red, the next pending recording is highlighted green.

Screenshot of the EPG (Electronic Program Guide) Window
Here you can see a typical day on german television.