no output from exec in prepareSingleImage method - PHPZxingDecoder.php

[mehulcs]

File : PHPZxingDecoder.php
Line number : 161

exec($command, $script_output);

In the above code, $script_output doesn't contain anything when the barcode from image is successfully found. But when the barcode is not found or not parsed, This variable contains file://filepath : No barcode found.

Running the same command in shell logs output of barcode data. Same command when executed in php, $script_output doesn't contain anything.

Thanks.