Image GD调整大小问题

Question

所以我想拍摄两张大图片（但后来我会梳理6张图片），将它们调整到x，y宽度，我从photoshop拍摄的高度，然后将它们合并合成一张460 x 230大小的图像。

这是我使用

<?php 

$dest = imagecreatefrompng('https://blzgdapipro-a.akamaihd.net/hero/ana/career-portrait.png'); 
$src = imagecreatefrompng('https://blzgdapipro-a.akamaihd.net/game/rank-icons/season-2/rank-6.png'); 

imagealphablending($dest, false); 
imagesavealpha($dest, true); 

imagealphablending($src, false); 
imagesavealpha($src, true); 


//imagescale($dest, 396, 161.92); 
$some = imagecreate(460, 230); 

$dest2 = resize($dest, 396, 162); 
$src2 = resize($src, 79.19, 79.19); 

//imagecopyresized($dest, $dest, 0, 0, 0, 0, 396, 161.92, 1098, 449); 
imagecopyresized($src, $src, 10, 10, 0, 0, 79.19, 79.19, 256, 256); 
//$img2 = imagecopymerge($dest, $src, 0, 0, 0, 0, 256, 256, 100); //have to play with these numbers for it to work for you, etc. 
imagecopymerge($dest2, $src2, 0, 0, 0, 0, 460, 230, 50); 

header('Content-Type: image/png'); 
imagepng($dest, 'merged2.png'); 
imagepng($dest2); 
//file_put_contents('merged.png', $contents); 
imagedestroy($dest); 
imagedestroy($src); 
imagedestroy($some); 
imagedestroy($dest2); 
imagedestroy($src2); 
imagedestroy($img2); 
//imagedestroy($then); 

function resize($img, $width, $height, $stretch = false) 
    { 
     $temp = imagecreatetruecolor($width, $height); 
     imagealphablending($temp, true); 
     imagesavealpha($temp, true); 

     $bg = imagecolorallocatealpha($temp, 0, 0, 0, 0); // Background color 
     imagefill($temp, 0, 0, $bg); 

     if ($stretch) 
     { 
      imagecopyresampled($temp, img, 0, 0, 0, 0, $width, $height, imagesx($img), imagesy($img)); 
     } 
     else 
     { 
      if (imagesx($img) <= $width && imagesy($img) <= $height) 
      { 
       $fwidth = imagesx($img); 
       $fheight = imagesy($img); 
      } 
      else 
      { 
       $wscale = $width/imagesx($img); 
       $hscale = $height/imagesy($img); 
       $scale = min($wscale, $hscale); 
       $fwidth = $scale * imagesx($img); 
       $fheight = $scale * imagesy($img); 
      } 
      imagecopyresampled($temp, 
       $img, 
       ($width - $fwidth)/2, ($height - $fheight)/2, 
       0, 0, 
       $fwidth, $fheight, 
       imagesx($img), imagesy($img) 
      ); 
     } 
     return $temp; 
    } 

，因为这条线的问题是，呈现的图像非常褪色 代码：

imagecopymerge($dest2, $src2, 0, 0, 0, 0, 460, 230, 50);

如果我改变了50，这是PCT值为100，它显示一个黑色背景图像（掩盖另一个图像），但如果我将其更改为0，它只显示另一个黑色背景图像（掩盖另一个图像） 如果值为0或100，则显示的图像全色。如何将这两幅图像合并在一起，同时保持它们的透明度和色彩活力？

Answer 1

而不是imagecopymerge使用imagecopy。你也总是需要正确指定的源图像的尺寸进行复印时：

$dest = imagecreatefrompng('https://blzgdapipro-a.akamaihd.net/hero/ana/career-portrait.png'); 
$src = imagecreatefrompng('https://blzgdapipro-a.akamaihd.net/game/rank-icons/season-2/rank-6.png'); 

$dest2 = resize($dest, 396, 162); 
imagedestroy($dest); 
$src2 = resize($src, 79, 79); // should be int not float. 
imagedestroy($src); 

// the last 2 params must match the width/height of the $src2 image. 
imagecopy($dest2, $src2, 0, 0, 0, 0, 79, 79); 
imagedestroy($src2); 

header('Content-Type: image/png'); 
imagepng($dest2); 

imagedestroy($dest2); 

你并不需要更改$dest或$src阿尔法设置，因为他们没有被渲染 - 您呈现的新形象资源在您的resize函数中创建并返回。因此你需要稍微改变一下功能：

function resize($img, $width, $height, $stretch = false) 
{ 
    $temp = imagecreatetruecolor($width, $height); 
    imagealphablending($temp, false); // changed to false. 
    imagesavealpha($temp, true); 
    ... 

---

编辑：

你可能会更好只需使用imagescale功能，而不是使用自己的resize功能：

$dest = imagecreatefrompng('https://blzgdapipro-a.akamaihd.net/hero/ana/career-portrait.png'); 
$src = imagecreatefrompng('https://blzgdapipro-a.akamaihd.net/game/rank-icons/season-2/rank-6.png'); 

$dest2 = imagescale($dest, 396); 
imagealphablending($dest2, false); 
imagesavealpha($dest2, true); 
$src2 = imagescale($src, 79); 

imagecopy($dest2, $src2, 0, 0, 0, 0, 79, 79); 

header('Content-Type: image/png'); 
imagepng($dest2); 

imagedestroy($dest); 
imagedestroy($src); 
imagedestroy($dest2); 
imagedestroy($src2);