[MPlayer-dev-eng] [PATCH] DOCS/video.html -vo zr update
rsnel at cube.dyndns.org
rsnel at cube.dyndns.org
Thu Aug 29 15:47:41 CEST 2002
Hello,
Here is a patch that updates the outdated zr section of TFM. It includes
an explanation of the options, some examples and an explanation of the
cinerama mode.
Please apply.
Greetings,
Rik.
--
Nothing is ever a total loss; it can always serve as a bad example.
-------------- next part --------------
Index: video.html
===================================================================
RCS file: /cvsroot/mplayer/main/DOCS/video.html,v
retrieving revision 1.95
diff -u -r1.95 video.html
--- video.html 27 Aug 2002 18:06:07 -0000 1.95
+++ video.html 29 Aug 2002 13:56:56 -0000
@@ -993,34 +993,115 @@
<P>This is a display-driver (<CODE>-vo zr</CODE>) for a number of MJPEG
capture/playback cards (tested for DC10+ and Buz, and it should work for the
- LML33, the DC10). The driver works by encoding the frame to jpeg and then
- sending it to the card. For the jpeg encoding <B>libavcodec</B> is
+ LML33 and the original DC10). The driver works by encoding the frame to jpeg
+ and then sending it to the card. For the jpeg encoding <B>libavcodec</B> is
used, and required.</P>
<P>This driver talks to the kernel driver available at
<A HREF="http://mjpeg.sourceforge.net">http://mjpeg.sourceforge.net</A>, so
- you must get it working first. Then recompile <B>MPlayer</B> with
- <CODE>--enable-zr</CODE>.</P>
+ you must get it working first. The presence of an MJPEG card is autodetected
+ by the configure script, if autodetection fails, force dection with
-Some remarks:
-<UL>
- <LI>don't start or stop XawTV on the playback device during playback,
- it will crash your computer. It is, however, fine to <B>FIRST</B> start
- XawTV, <B>THEN</B> start <B>MPlayer</B>, wait for <B>MPlayer</B> to finish
- and <B>THEN</B> stop XawTV.</LI>
- <LI>this driver adds <CODE>-zr*</CODE> command line options. The explanation
- of these options can be viewed with <CODE>-zrhelp</CODE>. It is possible to
- crop the input frame (cut borders to make it fit or to enhance performance)
- and to do other things.</LI>
- <LI>the driver takes data in YV12 and YUY2 format, this means that some
- codecs won't work. Some old VfW (Video for Windows) codecs, for example,
- are incompatible with this driver. The error message that you will see is:
- <CODE>Sorry, selected video_out device is incompatible with this codec.
- </CODE></LI>
- <LI>OSD is currently not supported, so you won't see
- subtitles.</LI>
-</UL>
+<PRE>
+ ./configure --enable-zr
+</PRE>
+The output can be controlled by several options:
+
+<DL>
+ <DT><CODE>-zrcrop</CODE></DT>
+ <DD>select a part of the input image for display, multiple occurances of
+ this option switch on <I>cinerama</I> mode (see below)</DD>
+
+ <DT><CODE>-zrxdoff, -zrydoff</CODE></DT>
+ <DD>if the movie is smaller than the tv screen, these options control the
+ position of the movie relative to the upper left corner of the screen,
+ the movie appears centered by default</DD>
+
+ <DT><CODE>-zrvdec, -zrhdec</CODE></DT>
+ <DD>vertical/horizontal decimation: ask the
+ driver to send only every <CODE>2</CODE>nd or <CODE>4</CODE>th line/pixel
+ of the input image to the MJPEG card and use the scaler of the MJPEG card
+ to stretch the image to its original size.</DD>
+
+ <DT><CODE>-zrfd</CODE></DT>
+ <DD>force decimation: decimation as specified by <CODE>
+ -zrhdec</CODE> and <CODE>-zrvdec</CODE>, only happens if the hardware
+ scaler can stretch the image to its original size, us this option to
+ force decimation</DD>
+
+ <DT><CODE>-zrbw</CODE></DT>
+ <DD>display in black and white</DD>
+
+ <DT><CODE>-zrquality</CODE></DT>
+ <DD>a number from <CODE>1</CODE> to <CODE>20</CODE> representing the jpeg
+ encoding quality, <CODE>1</CODE> gives the best quality</CODE> and
+ <CODE>20</CODE> gives very bad quality</DD>
+
+ <DT><CODE>-zrdev</CODE></DT>
+ <DD>specify the device file that belongs to your MJPEG card, by default this
+ driver takes the first v3l device it can find</DD>
+
+ <DT><CODE>-zrnorm</CODE></DT>
+ <DD>specift norm PAL/NTSC, the default is 'no change'</DD>
+
+ <DT><CODE>-zrhelp</CODE></DT>
+ <DD>display a list of all <CODE>-zr*</CODE> options and their default
+ values</DD>
+</DL>
+
+<P>Things like scaling and the OSD (on screen display) are not handled by
+ this driver but can be done using the video filters. For example,
+ suppose that you have a movie with a resolution of <CODE>512x272</CODE> and
+ you want to view it fullscreen on your DC10+. There are three main
+ possibilities, you may scale the movie to a width of <CODE>768</CODE>,
+ <CODE>384</CODE> or <CODE>192</CODE>. For performance and quality reasons,
+ I would choose to scale the movie to <CODE>384x204</CODE> using the fast
+ bilinear software scaler. The commandline is
+
+<PRE>
+ mplayer -vo zr -sws 0 -vop scale=384:204 movie.avi
+</PRE>
+
+<P>Cropping can be done by the <CODE>crop</CODE> filter and by
+ this driver itself. Suppose that a movie is too wide for display on your
+ Buz and that you want to use <CODE>-zrcrop</CODE> to make the movie less
+ wide, the you would issue the following command
+
+<PRE>
+ mplayer -vo zr -zrcrop 720x320+80+0 benhur.avi
+</PRE>
+
+ if you want to use the <CODE>crop</CODE> filter, you would do
+
+<PRE>
+ mplayer -vo zr -vop crop=720:320:80:0 benhur.avi
+</PRE>
+
+<P>Extra occurances of <CODE>-zrcrop</CODE> invoke <I>cinerama</I> mode, i.e.
+ you can distribute the movie over several tv's or beamers to create a larger
+ screen. Suppose you have two beamers. The left one is connected to your Buz
+ at <CODE>/dev/video1</CODE> and the right one is connected to your DC10+ at
+ <CODE>/dev/video0</CODE>. The movie has a resolution of <CODE>704x288</CODE>.
+ Suppose also that you want the right beamer in black and white and that
+ the right beamer should have jpeg frames at quality <CODE>10</CODE>,
+ then you would issue the following command
+
+<PRE>
+ mplayer -vo zr -zrdev /dev/video0 -zrcrop 352x288+352 -zrxdoff 0 -zrbw \
+ -zrcrop 352x288+0+0 -zrdev /dev/video1 -zrquality 10 movie.avi
+</PRE>
+
+<P>You see that the options appearing before the second <CODE>-zrcrop</CODE>
+ only apply to the DC10+ and that the options after the second
+ <CODE>-zrcrop</CODE> apply to the Buz. The maximum number of MJPEG cards
+ participating in <I>cinerama</I> is four, so you can buid a <CODE>2x2</CODE>
+ vidiwall.</P>
+
+<P>Finally an important remark: don't start or stop XawTV on the playback
+ device during playback, it will crash your computer. It is, however, fine to
+ <B>FIRST</B> start XawTV, <B>THEN</B> start <B>MPlayer</B>, wait for
+ <B>MPlayer</B> to finish and <B>THEN</B> stop XawTV.</P>
<H4><A NAME="dvb">2.3.1.16 DVB</A></H4>
More information about the MPlayer-dev-eng
mailing list