| Subject: | screenshot(left=>....) keeps crashing |
| Date: | Sun, 14 Jun 2009 12:26:03 +0200 |
| To: | bug-Imager-Screenshot [...] rt.cpan.org |
| From: | Robert Spitzenpfeil <robert [...] spitzenpfeil.org> |
Hi,
I'm using screenshot to rapidly capture a small section of my screen and
send it off to a display.
When it fails, this is what die("error: $!") spits out:
error: Resource temporarily unavailable at ./screen_video.pl line 66.
I'm on opensuse 11.0 32bit
I've attached my code. It would be nice if you could shed some light on
why or what interferes here.
Regards,
Robert
#!/usr/bin/perl -W
use strict;
use Device::SerialPort;
use Time::HiRes qw(sleep);
use Imager;
use Imager::Screenshot 'screenshot';
my $start_byte = "\n"; # 0x0A
my $stop_byte = "\r"; # 0x0D
my $color_scaler = 8; # image has 0-255 for each color, too much for the matrix board
my $port = "/dev/ttyUSB0"; # <-- find right port !
my $link = Device::SerialPort->new($port) || die("could not open port: $port - $!"); # <-- match to right com port
$link->databits(8);
$link->baudrate(57600); # <-- match to arduino settings
$link->parity("none");
$link->stopbits(1);
$| = 1; # buffers disabled
sleep 4; # wait until the arduino bootloader has timed out
my $row;
my $led;
my $red;
my $green;
my $blue;
my $alpha;
my @scanline;
my $img;
my $newimg;
my $line;
my @coords;
my $x;
my $y;
my $left;
my $right;
my $top;
my $bottom;
my $x_box_size = $ARGV[0] || 8;
my $y_box_size = $ARGV[1] || 8;
while (1) {
@coords = `xinput query-state Mouse[1]`; # you need to adapt this to your system. use "xinput list" to get all X11 devices
foreach $line ( @coords ) {
$line =~ m/^.*valuator\[0\]\=(\d{1,4})/;
$x = $1;
$line =~ m/^.*valuator\[1\]\=(\d{1,4})/;
$y = $1;
}
$left = $x-$x_box_size/2;
$top = $y-$y_box_size/2;
$right = $x+$x_box_size/2;
$bottom = $y+$y_box_size/2;
#print "x: ",$x,"\n";
#print "y: ",$y,"\n";
#print"xbs: ",$x_box_size,", ybs: ",$y_box_size,"\n";
#print $left,",",$top,",",$right,",",$bottom,"\n";
while ( ! defined($img) ) {
$img = screenshot(left=>$left,right=>$right,top=>$top,bottom=>$bottom) || die("error: $!"); # on linux get the curser position using 'xinput query-state Mouse[1]' or similar
sleep(0.020);
}
$newimg = $img->scale(xpixels=>8, ypixels=>8);
undef($img);
for ($row = 0; $row < 8; $row++) {
$link->write($start_byte);
@scanline = $newimg->getscanline(y=>$row);
for ($led = 0; $led < 8; $led++) {
($red,$green,$blue,$alpha) = $scanline[$led]->rgba;
$link->write(pack("C",$row));
$link->write(pack("C",$led));
$link->write(pack("C",$red/$color_scaler));
$link->write(pack("C",$green/$color_scaler));
$link->write(pack("C",$blue/$color_scaler));
#print $row,$led,"\n";
#print unpack("C",$image[$row*3*8+$led*3+0]),"\n";
#print unpack("C",$image[$row*3*8+$led*3+1]),"\n";
#print unpack("C",$image[$row*3*8+$led*3+2]),"\n\n";
sleep(0.001);
}
$link->write($stop_byte);
sleep(0.001);
}
}