[MPlayer-dev-eng] [PATCH] DC10+ (and alike) TV-Out support

Rik Snel rsnel at cube.dyndns.org
Wed Jan 16 17:23:06 CET 2002


Hello all,

This is a patch that I sent earlier, but with an improper subject line.
Be sure to read the remarks. They mention that this patch adds new
commandline options and that is messes with global compilation options to
fix a conflict between libavcodec and libjpeg-6.

----
This patch adds a display-driver (-vo zr) 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 I use the standard
libjpeg-6b (I tried to use the mjpeg codec from ffmpeg, but it couldn't
get it to generate a JPEG in the YUV422 format (internal), the hardware
only takes YUV422 jpegs, the code is still there and it can be made to
work if/when libavcodec generates YV12 jpegs)

Remarks:

-users must only complain about this driver if they got the mjpegtools
working. They include the most recent kernel driver and playback/record
utilities. (if that doesn't work than this driver is not the problem,
because this driver talks to the kernel driver from the
mjpeg.sourceforge.net)

-don't start or stop xawtv on the same device that is, at the same time,
being used by mplayer (this will crash your computer)

-This driver adds -zr* commandline options, the explanation of the options
can be viewed with -zrhelp. It is possible to crop the input frame (cut
borders to make it fit or to enhance performace) and to do other things.

-The driver only gets compiled if --enable-zr is specified on the
configure commandline. (and if libjpeg is present)

-The was a conflict between the jpeg_fdct_ifast from libavcodec and
the one from libjpeg-6b. I added -Djpeg_fdct_ifast=jpeg_fdct_ifast2
to the OPTFLAGS. (without a fix the jpeg compression aborts with 'DCT
coeffcient out of range' in Integer Fast mode) It is probably better to
change the name of the function in libavcodec...

-configure checks for libjpeg

-A/V sync is decent

-performance: my AMD K6-2 can play a PAL VCD at vertical decimation 2
(throw half of the lines away) in Integer Fast mode at quality 70 without
frame drop.

-some (factor 2, 4) hardware scaling, it will automatically do the right
thing. (helped by -zrfi 'force interlace')

-The driver only takes data in the YV12 format.

Greetings,

Rik.

--------
Nothing is ever a total loss; it can always serve as a bad example.




More information about the MPlayer-dev-eng mailing list