Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:116616
Message-ID: <4e195dd4-ecb5-fcb5-668f-cabb9635b74a@gmx.de>
Date: Thu, 9 Dec 2021 22:56:50 +0100
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101
 Thunderbird/91.3.2
Content-Language: de-DE
To: =?UTF-8?Q?Fl=c3=a1vio_Heleno?= <flaviohbatista@gmail.com>,
 Nikita Popov <nikita.ppv@gmail.com>
Cc: Ben Morss <morss@google.com>, PHP internals <internals@lists.php.net>
References: <CAA6+j4tx8ZadUi_P7y-o_U0eN+UsW38FvBYBk_EDHTpdMTTLVQ@mail.gmail.com>
 <7c4411c8-8bf6-36f1-36f8-1a7391c2a3d7@gmx.de>
 <CAF+90c_PjHD5NqmZxAiWhnrrRnpYcYW=xEt_YyFL2sZFoJFsug@mail.gmail.com>
 <CAAwFBqrf2Ldy9Qjdn3FGrOmgza0kBHBa+gqNXkoK+Y_7s52fMA@mail.gmail.com>
In-Reply-To: <CAAwFBqrf2Ldy9Qjdn3FGrOmgza0kBHBa+gqNXkoK+Y_7s52fMA@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: quoted-printable
Subject: Re: [PHP-DEV] Re: Finishing AVIF support in getimagesize()
From: cmbecker69@gmx.de ("Christoph M. Becker")

On 09.12.2021 at 20:59, Fl=C3=A1vio Heleno wrote:

> On Thu, Dec 9, 2021 at 4:46 PM Nikita Popov <nikita.ppv@gmail.com> wrote=
:
>
>> On Wed, Dec 8, 2021 at 12:41 PM Christoph M. Becker <cmbecker69@gmx.de>
>> wrote:
>>
>>> On 01.12.2021 at 00:52, Ben Morss via internals wrote:
>>>
>>>> Earlier this year, I added support for AVIF images
>>>> <https://github.com/libgd/libgd/pull/671> to libgd
>>>> <https://github.com/libgd/libgd>. My ultimate goal was to bring
>> support
>>> for
>>>> this new image format to PHP, so that the world's top CMSs could let
>>> sites
>>>> serve AVIFs. A few of you kindly guided me as I made my first
>>> contributions
>>>> to the PHP codebase, propagating libgd's new AVIF support
>>>> <https://github.com/php/php-src/pull/7026> into PHP's bundled gd fork=
,
>>>> and adding
>>>> AVIF awareness <https://github.com/php/php-src/pull/7091> to non-gd
>>>> functions like getimagesize() and imagecreatefromstring().
>>>>
>>>> Unfortunately, when I worked on getimagesize(), AVIF experts advised
>> that
>>>> there was no compact, reliable way to determine the size of an AVIF
>> image
>>>> without relying on an external library like libavif. We decided
>>>> <https://github.com/php/php-src/pull/5127#issuecomment-799825277> tha=
t
>>> it
>>>> was useful to return the information that a given image was an AVIF,
>> but
>>>> simply to return 0 for the actual dimensions and other details. The
>> user
>>>> would simply need to decode the image to determine this information.
>>>>
>>>> Of course, users would really like
>>>> <https://github.com/php/php-src/pull/5127#issuecomment-976241397> to
>> use
>>>> getimagesize() to return the actual size. So a colleague has kindly
>>>> created standalone
>>>> code <https://aomedia-review.googlesource.com/c/libavifinfo/+/148321>
>>> (that
>>>> doesn't depend on libavif) to do this, with the goal of adding it to
>> PHP.
>>>>
>>>> The code comprises several hundred lines. But - it works, and it work=
s
>>> well.
>>>>
>>>> Would it be ok to submit a PR containing this code to add this
>>>> functionality? Or does someone have a superior approach?
>>>
>>> Thanks for your and your colleague's work!  It's highly appreciated.
>>>
>>> Anyhow, a respective PR[1] has been submitted now, and I'm in favor of
>>> bundling libavifinfo.  I'm not too concerned regarding the additional
>>> size of the PHP binaries which would result by linking it in, but if
>>> others are, we could still introduce a configuration option (e.g.
>>> `--with-libavifinfo`).
>>>
>>> Thoughts?  Objections to bundling libavifinfo at all?
>>>
>>> [1] <https://github.com/php/php-src/pull/7711>
>>>
>>
>> Assuming no licensing concerns, bundling libavifinfo sounds reasonable.=
 The
>> library is small, our avif functionality is incomplete without it, and =
we
>> can't expect this to be available as a system library at this time.
>> Although I'm not a core contributor, my 2c is that even with libavifinf=
o
> bundled, a configuration option is
> very welcome, the same way we have for png, jpeg, xpm and webp.

Whether AVIF support should be included for ext/gd is already
configurable.  This is solely about the getimagesize(fromstring) and
image_type_to_* functions which are part of ext/std.  We do not have
configuration options for these for the other image formats either.

=2D-
Christoph M. Becker