# What to do with image2wbmp()? - Thread: https://externals.io/message/102025 - Original archive: https://news-web.php.net/php.internals/102025 - Started by Christoph M. Becker on 2018-04-05T12:04:03+00:00 - Messages: 3 - RFC: Deprecate and Remove image2wbmp() (Implemented (PHP 7.3)) — https://externals.io/rfc/image2wbmp.md - Reply by email to internals@lists.php.net - More for agents: search with https://externals.io/search.md?q={query} · RFCs at https://externals.io/rfc.md · JSON API at https://externals.io/api · documentation at https://externals.io/llms.txt --- ## #102025 — Christoph M. Becker — 2018-04-05T12:04:03+00:00 URL: https://externals.io/message/102025#102025 Hi everybody! is still unresolved, and I'm not sure how to resolve it. TL;DR: the $threshold parameter of image2wbmp() is supposed to specify a *brightness threshold* for the required black and white conversion of the image. However, as of PHP 5.0.0 it is actually interpreted as the *foreground color*; all other colors are treated as background. This makes image2wbmp() basically identical to imagewbmp(). Any suggestions on how to proceed here? -- Christoph M. Becker --- ## #102034 — Kalle Sommer Nielsen — 2018-04-13T04:58:23+00:00 URL: https://externals.io/message/102025#102034 · In reply to: #102025 Hi 2018-04-05 14:04 GMT+02:00 Christoph M. Becker : > Hi everybody! > > is still unresolved, and I'm not sure how > to resolve it. > > TL;DR: the $threshold parameter of image2wbmp() is supposed to specify a > *brightness threshold* for the required black and white conversion of > the image. However, as of PHP 5.0.0 it is actually interpreted as the > *foreground color*; all other colors are treated as background. This > makes image2wbmp() basically identical to imagewbmp(). > > Any suggestions on how to proceed here? If thats the case that its basically identical, then a PHP_DEP_FE should be sufficient for image2wbmp() and a removal in future version, given its a rarely used function and migration is easy, even 7.4 could potentially be fine for removal. -- regards, Kalle Sommer Nielsen kalle@php.net --- ## #102063 — Christoph M. Becker — 2018-04-19T23:09:51+00:00 URL: https://externals.io/message/102025#102063 · In reply to: #102034 > 2018-04-05 14:04 GMT+02:00 Christoph M. Becker : > > > […] > > If thats the case that its basically identical, then a PHP_DEP_FE > should be sufficient for image2wbmp() and a removal in future version, > given its a rarely used function and migration is easy, even 7.4 could > potentially be fine for removal. Thanks, Kalle! To clarify the behavioral problem: image2wbmp() is supposed to use _php_image_bw_convert() to do the conversion. However, that does not happen anymore since the commit[1] I've mentioned in the bug report. The problem is that the fallthrough to case PHP_GDIMG_TYPE_JPEG[2] had been intended (but not documented!), so that _php_image_bw_convert() (which is stored in func_p) would have been called, but now gdImageWBMP()[3] is called directly without converting to a black and white image according to the given threshold. It is quite interesting that it took apparently more than *ten* years until the bug has been reported[4]. This might be due to nobody using WBMP (see , though). Anyhow, I have to agree to the deprecation/removal suggestion, since: * fixing *this* 10y old bug is likely to cause more harm than good * a B/W conversion should be a *general* feature of GD (or likely rather libgd) * the B/W conversion[5] is very simplistic, and does not fit to gdImageGrayScale()'s[6] algorithm[7] I shall pursue the RFC process. [1] [2] [3] [4] [5] [6] [7] -- Christoph M. Becker