png2wbmp

Function name: png2wbmp()

Applicable version: PHP 4.0.5 or above

Usage: The png2wbmp() function is used to convert PNG images to WBMP images. WBMP is a lossless black and white image format that is commonly used to display images on mobile devices.

Syntax: bool png2wbmp ( string $pngname , string $wbmpname , int $dest_height , int $dest_width , int $threshold )

parameter:

• $pngname: The file path of the PNG image to be converted.
• $wbmpname: The file path of the converted WBMP image.
• $dest_height: The height of the target image (pixel).
• $dest_width: The width of the target image (pixels).
• $threshold: Optional parameter to specify the threshold value used in the conversion. The default value is 0.

Return value: Return true if the conversion is successful, otherwise return false.

Example:

 $pngFile = 'path/to/image.png'; $wbmpFile = 'path/to/output.wbmp'; $destHeight = 100; // 目标图像的高度$destWidth = 100; // 目标图像的宽度$threshold = 0; // 阈值，默认为0 if (png2wbmp($pngFile, $wbmpFile, $destHeight, $destWidth, $threshold)) { echo "PNG图像成功转换为WBMP图像！"; } else { echo "转换失败，请检查参数或文件路径是否正确。"; }

Notes:

1. Before calling this function, you need to make sure that PHP has enabled GD extensions, otherwise the function call will fail.
2. The converted WBMP image will overwrite any existing files in the target file path, so make sure the target file path is writable and does not contain important data.
3. The size of the converted WBMP image will be adjusted according to the target height and width, which may cause image deformation. Please select the appropriate target size according to actual needs.
4. The threshold parameter is used to specify the binarized threshold during the conversion process. A smaller threshold will produce more black pixels, and a larger threshold will produce more white pixels. Adjust as needed.
5. If the conversion fails, you can get detailed error information by checking the error log or using the error_get_last() function.