/**
* Estimate an upper limit of the processable image dimensions.
* This will be in the scale of ~40 MP for 256 MB memory_limit and
* ~16 MP for 128 MB. See Okapi::init_internals() for current memory_limit.
*/
private static function max_pixels($base64_image)
{
$bytes_per_pixel = 5;
# GD needs 5 bytes per pixel for "true color"
$available_memory = Okapi::php_ini_get_bytes('memory_limit') - memory_get_usage();
$available_memory -= 16 * 1024 * 1024;
# reserve
$available_memory -= strlen($base64_image);
# will be copied for EXIF processing
$available_memory -= 3 * $bytes_per_pixel * Settings::get('IMAGE_MAX_PIXEL_COUNT');
# processing buffers
return floor($available_memory / $bytes_per_pixel);
}
