Add blind-chroma-key

Signed-off-by: Mattias Andrée <maandree@kth.se>

3 files changed, 47 insertions, 4 deletions

diff --git a/man/blind-chroma-key.1 b/man/blind-chroma-key.1
new file mode 100644
index 0000000..f185226
--- /dev/null
+++ b/man/blind-chroma-key.1
@@ -0,0 +1,39 @@
+.TH BLIND-CHROMA-KEY 1 blind
+.SH NAME
+blind-chroma-key - Replace a colour range with transparency
+.SH SYNOPSIS
+.B blind-chroma-key
+.I key-stream
+.SH DESCRIPTION
+.B blind-chroma-key
+reads a video from stdin and colours from
+.IR key-stream .
+Each frame in
+.I key-stream
+should contain exactly two pixels. The colour of
+the first pixel, and all colours with a distance
+from that colour upto the same distance the colour
+of the second pixel has to that colour, will be
+turned into transparency in the video from stdin,
+and the resulting video will be printed to stdout.
+.P
+If the two colours in a frame from
+.I key-stream
+have the same alpha value, all matching colours
+will be turned into full transparency. Otherwise,
+the colours matching the first colour will be
+given the transparency specified with the first
+colour, all other matching colours will have
+a transparency between to two specified alpha
+values. However, if alpha value of the second
+colour is less than the alpha value of the first
+colour, twos alpha values are inverted.
+.SH SEE ALSO
+.BR blind (7),
+.BR blind-from-text (1),
+.BR blind-colour-ciexyz (1),
+.BR blind-colour-srgb (1),
+.BR blind-dual-key (1)
+.SH AUTHORS
+Mattias Andrée
+.RI < maandree@kth.se >
diff --git a/man/blind-dual-key.1 b/man/blind-dual-key.1
index 6cfe7b8..f951d10 100644
--- a/man/blind-dual-key.1
+++ b/man/blind-dual-key.1
@@ -9,11 +9,11 @@ blind-dual-key - Apply transparency to a video based on two videos and two key
 .I dual-X
 .I dual-Y
 .I dual-Z
-.I dual-video
+.I dual-stream
 .SH DESCRIPTION
 .B blind-dual-key
 reads a video from stdin and a video
-.IR dual-video .
+.IR dual-stream .
 These two videos should be idential, except
 with two different background colours. The
 background colour used in the video from
@@ -24,7 +24,7 @@ and
 .IR Z ,
 using the CIE XYZ colour model. The
 background colour used in the video from
-.I dual-video
+.I dual-stream
 should be specified in the arguments
 .IR dual-X ,
 .IR dual-Y ,
@@ -49,7 +49,8 @@ example black and white or green and magenta.
 .SH SEE ALSO
 .BR blind (7),
 .BR blind-colour-ciexyz (1),
-.BR blind-colour-srgb (1)
+.BR blind-colour-srgb (1),
+.BR blind-chroma-key (1)
 .SH AUTHORS
 Mattias Andrée
 .RI < maandree@kth.se >
diff --git a/man/blind.7 b/man/blind.7
index f8295fe..8044f0d 100644
--- a/man/blind.7
+++ b/man/blind.7
@@ -28,6 +28,9 @@ Place videos side by side
 .BR blind-cat-rows (1)
 Stack videos vertically
 .TP
+.BR blind-chroma-key(1)
+Replace a colour range with transparency
+.TP
 .BR blind-colour-ciexyz (1)
 Convert CIE XYZ for use with
 .BR blind-single-colour (1)