Bug->Doc #73317 [Opn->Csd]: image2wbmp() interprets $threshold as $fg

Edit report at https://bugs.php.net/bug.php?id=73317&edit=1 ID: 73317 Updated by: cmb@php.net Reported by: cmb@php.net Summary: image2wbmp() interprets $threshold as $fg -Status: Open +Status: Closed -Type: Bug +Type: Documentation Problem Package: GD related Operating System: * PHP Version: 5.6.26 -Assigned To: +Assigned To: cmb Block user comment: N Private report: N New Comment: Accoding to the “Deprecate and Remove image2wbmp()” RFC[1], it has been decided to stick with the current behavior (and to deprecate and later remove image2wbmp). Therefore, this is merely a documentation problem, which already has been resolved[2]. [1] <https://wiki.php.net/rfc/image2wbmp> [2] <http://svn.php.net/viewvc?view=revision&revision=345112> Previous Comments: ------------------------------------------------------------------------ [2018-04-03 11:55:46] cmb@php.net Related To: Bug #76179 ------------------------------------------------------------------------ [2016-10-13 16:38:46] cmb@php.net Description: ------------ The $threshold parameter of image2wbmp() is supposed to specify the brightness threshold for the necessary black/white conversion. However, as of commit cb5c9156[1], $threshold is interpreted as the color which is used as foreground color. As this behavioral change has been introduced with PHP 5.0.0 it might seem best to change the documentation accordingly to avoid a BC break. However, as it's now image2wbmp() basically behaves identical to imagewbmp() (the latter also allows to pass a stream as second parameter as of PHP 5.4.0), and as such makes no sense at all. Furthermore, there is no readily available solution for converting an image to black and white according to a given threshold, what appears to be required for general WBMP support. Applying imagefilter() with IMG_FILTER_CONTRAST and IMG_FILTER_GRAYSCALE might deliver this functionality, though. And of course, one could output the image as PNG and use png2wbmp(). [1] <http://git.php.net/?p=php-src.git;a=commit;h=cb5c9156c233a260e7a588141863720de82d2926> Test script: --------------- <?php $im = imagecreate(100, 100); imagecolorallocate($im, 0, 0, 0); $white = imagecolorallocate($im, 255, 255, 255); $red = imagecolorallocate($im, 255, 0, 0); $light = imagecolorallocate($im, 192, 192, 192); $dark = imagecolorallocate($im, 64, 64, 64); imagefilledellipse($im, 25, 25, 40, 40, $white); imagefilledellipse($im, 75, 25, 40, 40, $red); imagefilledellipse($im, 25, 75, 40, 40, $light); imagefilledellipse($im, 75, 75, 40, 40, $dark); image2wbmp($im, __DIR__ . DIRECTORY_SEPARATOR . 'image2wbmp.wbmp', $dark); Expected result: ---------------- An image with black background and two white circles in the upper and lower left quadrant, respectively. Actual result: -------------- An image with white background and a single black circle in the lower right quadrant. ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=73317&edit=1