The command for png optimization plugin Optipng:
The tutorial for using the command
Synopsis: optipng [options] files ...
Files: Image files of type: PNG, BMP, GIF, PNM or TIFF
Basic options:
-?, -h, -help show the extended help
-o optimization level (0-7) [default: 2]
-v run in verbose mode / show copyright and version info
Examples:
optipng file.png
(default speed)
optipng -o5 file.png
(slow)
optipng -o7 file.png
(very slow)
Type "optipng -h" for extended help.
Then I run the following PHP code
$txt = shell_exec("C:\DSPadmin\DEV\optipng\optipng C:\Source\ChangSha\temp_process\production\zoomTxt\A06_text.png");
var_dump ($txt);
return NULL and nothing executed
But when I run the same command in the cmd shell I opened
C:\DSPadmin\DEV\optipng\optipng C:\Source\ChangSha\temp_process\production\zoomTxt\A06_text.png
It work as expected, how to fix the problem ? Thanks