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| author | Christoph M. Becker <cmbecker69@gmx.de> | 2020-05-22 09:11:28 +0200 |
|---|---|---|
| committer | Christoph M. Becker <cmbecker69@gmx.de> | 2020-05-22 09:15:41 +0200 |
| commit | d4bd6fb491ccaf70006d6f671755126b47a71bcb (patch) | |
| tree | ddf3950ecdc0e71d4d9b0e4f2d892420ee7a6a31 | |
| parent | 85ac5643ff07e07e40df89510726e1bc66e6a50b (diff) | |
| download | php-git-d4bd6fb491ccaf70006d6f671755126b47a71bcb.tar.gz | |
Fix #79615: Wrong GIF header written in GD GIFEncode
The color resolution is expected in bits 4-6 of the packed fields byte
of the logical screen descriptor (byte 10 of the GIF data stream),
according to the specification[1], section 18.
[1] <https://www.w3.org/Graphics/GIF/spec-gif89a.txt>
| -rw-r--r-- | NEWS | 3 | ||||
| -rw-r--r-- | ext/gd/libgd/gd_gif_out.c | 2 | ||||
| -rw-r--r-- | ext/gd/tests/bug79615.phpt | 20 |
3 files changed, 24 insertions, 1 deletions
@@ -6,6 +6,9 @@ PHP NEWS . Fixed bug #79566 (Private SHM is not private on Windows). (cmb) . Fixed bug #79489 (.user.ini does not inherit). (cmb) +- GD: + . Fixed bug #79615 (Wrong GIF header written in GD GIFEncode). (sageptr, cmb) + - MySQLnd: . Fixed bug #79596 (MySQL FLOAT truncates to int some locales). (cmb) diff --git a/ext/gd/libgd/gd_gif_out.c b/ext/gd/libgd/gd_gif_out.c index c0a0433f4d..771e8afe2e 100644 --- a/ext/gd/libgd/gd_gif_out.c +++ b/ext/gd/libgd/gd_gif_out.c @@ -319,7 +319,7 @@ GIFEncode(gdIOCtxPtr fp, int GWidth, int GHeight, int GInterlace, int Background /* * OR in the resolution */ - B |= (Resolution - 1) << 5; + B |= (Resolution - 1) << 4; /* * OR in the Bits per Pixel diff --git a/ext/gd/tests/bug79615.phpt b/ext/gd/tests/bug79615.phpt new file mode 100644 index 0000000000..b7cf9175c5 --- /dev/null +++ b/ext/gd/tests/bug79615.phpt @@ -0,0 +1,20 @@ +--TEST-- +Bug #79615 (Wrong GIF header written in GD GIFEncode) +--SKIPIF-- +<?php +if (!extension_loaded('gd')) die('skip gd extension not available'); +?> +--FILE-- +<?php +$im = imagecreate(3, 3); // 3x3, 9 colors, 4 bits per pixel +for ($x = 0; $x < 3; $x++) { + for ($y = 0; $y < 3; $y++) { + imagesetpixel($im, $x, $y, imagecolorallocate($im, $x, $y, 0)); + } +} +ob_start(); +imagegif($im); +echo decbin(ord(ob_get_clean()[0xA])); +?> +--EXPECT-- +10110011 |