--- doc/ffmpeg.1.orig	2004-08-29 12:38:34.000000000 +0200
+++ doc/ffmpeg.1	2004-08-29 13:03:08.000000000 +0200
@@ -505,21 +505,49 @@
 tell that the raw codec data must be copied as is.
 .Sh "Audio/Video grab options"
 .IX Subsection "Audio/Video grab options"
-.IP "\fB\-vd device\fR" 4
-.IX Item "-vd device"
-set video grab device (e.g. \fI/dev/video0\fR)
-.IP "\fB\-vc channel\fR" 4
-.IX Item "-vc channel"
-set video grab channel (\s-1DV1394\s0 only)
 .IP "\fB\-tvstd standard\fR" 4
 .IX Item "-tvstd standard"
 set television standard (\s-1NTSC\s0, \s-1PAL\s0 (\s-1SECAM\s0))
-.IP "\fB\-dv1394\fR" 4
-.IX Item "-dv1394"
-set \s-1DV1394\s0 grab
 .IP "\fB\-ad device\fR" 4
 .IX Item "-ad device"
 set audio device (e.g. \fI/dev/dsp\fR)
+.PP
+This build of ffmpeg includes NetBSD-specific patches that change the
+video-grabbing semantics. Recording from bktr(4) can be controlled via the
+following environment variables:
+.PP
+.RS
+.B BKTR_DEV
+(0\-4): which of the devices on the bktr should provide the signal (tuner,
+video-in,...)
+.PP
+.B BKTR_FORMAT
+(1\-6): TV format, 1 PAL 2 NTSC 3 SECAM 4 PALN 5 PALM 6 NTSCJ
+.PP
+.B BKTR_FREQUENCY
+(float): frequency to which the tuner should be set.
+.PP
+.B BKTR_CHANNEL
+(int): channel to which the tuner should be set, overrides BKTR_FREQUENCY
+.RE
+.PP
+If you set the channel or frequency with a different program such as xawtv
+or fxtv you might not get audio; try to use the environment variables in
+that case. Do not forget to set the following mixerctl variables to useful
+values:
+.PP
+.RS
+record.source=line
+.PP
+record.volume=255,255
+.PP
+inputs.line=255,255
+.RE
+.PP
+One possible command line would then be:
+.PP
+ffmpeg -y -intra -tvstd pal -vcodec mpeg2video -s 768x576 -b 9600 -ab 128 -ad
+/dev/audio -ac 2 -ar 44100 /tmp/file.mpg
 .Sh "Advanced options"
 .IX Subsection "Advanced options"
 .IP "\fB\-map file:stream\fR" 4