(PHP 7 >= 7.2.0)
imagebmp — Output a BMP image to browser or file
Outputs or saves a BMP version of the given image.
image由图象创建函数(例如imagecreatetruecolor())返回的图象资源。
to文件保存的路径，如果未设置或为 NULL，将会直接输出原始图象流。
Note:
NULLis invalid if thecompressedarguments is not used.
compressedWhether the BMP should be compressed with run-length encoding (RLE), or not.
成功时返回 TRUE， 或者在失败时返回 FALSE。
However, if libgd fails to output the image, this function returns TRUE.
Example #1 Saving a BMP file
<?php
// Create a blank image and add some text
$im = imagecreatetruecolor(120, 20);
$text_color = imagecolorallocate($im, 233, 14, 91);
imagestring($im, 1, 5, 5, 'BMP with PHP', $text_color);
// Save the image
imagebmp($im, 'php.bmp');
// Free up memory
imagedestroy($im);
?>