image_auto_rotate is very slow

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image_auto_rotate is very slow new!
by Dominik, 1 year, 9 months ago
Hi,

first thanks for this genius piece of software.
Just one thing:
The image_auto_rotate function is very slow on large pictures and takes endless.

I looked in the code and saw that you are using a nested for loop with the imagecopy() function. So that should be the reason why this thing lasts forever.

Could you change that please, maybe you could use the imagerotate() function?

Thank you!!Reply
Re: image_auto_rotate is very slow new!
by colin, 1 year, 9 months ago
I will see what's possible. I don't have much time right now, but I will gladly accept a patch if you have one.Reply
Re: image_auto_rotate is very slow new!
by Dominik, 1 year, 9 months ago
Thanks for your quick answer.

Maybe something like here: https://github.com/verot/class.upload.php/issues/8#issuecomment-128879652Reply
Re: image_auto_rotate is very slow new!
by Dominik, 1 year, 9 months ago
Also here:
https://www.php.net/manual/de/function.imagerotate.php#121741Reply
Re: image_auto_rotate is very slow new!
by Dominik, 1 year, 7 months ago
Hi Colin,

I have some update for you.
Haven't heard of you for a long time, so I did some code changes myself regarding the veeeery slow image_auto_rotate and auto_flip functions. (In fact sadly these aren't real functions but simple if-statements, if these would have been functions/methods I could have easily extended your class and create overrides methods...)

Here is the code I changed:
In your $auto_flip statement you need to replace this (Old):

for ($x = 0; $x < $this->image_src_x; $x++) {
    for ($y = 0; $y < $this->image_src_y; $y++){
        if (strpos($auto_flip, 'v') !== false) {
            imagecopy($tmp, $image_dst, $this->image_src_x - $x - 1, $y, $x, $y, 1, 1);
        } else {
            imagecopy($tmp, $image_dst, $x, $this->image_src_y - $y - 1, $x, $y, 1, 1);
        }
    }
}

with this (New):

// Copy the image
imagecopy($tmp, $image_dst, 0, 0, 0, 0, $this->image_src_x, $this->image_src_y);

// Flip the image
if (!imageflip($tmp, ($auto_flip == 'h' ? IMG_FLIP_HORIZONTAL : IMG_FLIP_VERTICAL)))
{
    throw new \LogicException('Unable to flip the image.');
}


And in your $auto_rotate statement you need to replace this (Old):

if ($auto_rotate == 90 || $auto_rotate == 270) {
    $tmp = $this->imagecreatenew($this->image_src_y, $this->image_src_x);
} else {
    $tmp = $this->imagecreatenew($this->image_src_x, $this->image_src_y);
}
$this->log .= '- auto-rotate image : ' . $auto_rotate . '';
for ($x = 0; $x < $this->image_src_x; $x++) {
    for ($y = 0; $y < $this->image_src_y; $y++){
        if ($auto_rotate == 90) {
            imagecopy($tmp, $image_dst, $y, $x, $x, $this->image_src_y - $y - 1, 1, 1);
        } else if ($auto_rotate == 180) {
            imagecopy($tmp, $image_dst, $x, $y, $this->image_src_x - $x - 1, $this->image_src_y - $y - 1, 1, 1);
        } else if ($auto_rotate == 270) {
            imagecopy($tmp, $image_dst, $y, $x, $this->image_src_x - $x - 1, $y, 1, 1);
        } else {
            imagecopy($tmp, $image_dst, $x, $y, $x, $y, 1, 1);
        }
    }
}

with this (New):

$tmp = $this->imagecreatenew($this->image_src_x, $this->image_src_y);
$this->log .= '- auto-rotate image : ' . $auto_rotate . '';

// Copy the image
imagecopy($tmp, $image_dst, 0, 0, 0, 0, $this->image_src_x, $this->image_src_y);

// Rotate the image
$tmp = imagerotate($tmp, $auto_rotate, 0);


To make it rotate the images correctly you also have to change your exif-orientation cases to this (New):

switch($orientation) {
  case 1:
    $this->log .= '- EXIF orientation = 1 : default';
    break;
  case 2:
    $auto_flip = 'h';
    $this->log .= '- EXIF orientation = 2 : horizontal flip';
    break;
  case 3:
    $auto_rotate = 180;
    $this->log .= '- EXIF orientation = 3 : 180 rotate';
    break;
  case 4:
    $auto_flip = 'h';
    $auto_rotate = 180;
    $this->log .= '- EXIF orientation = 4 : horizontal flip + 180 rotate';
    break;
  case 5:
    $auto_flip = 'h';
    $auto_rotate = 90;
    $this->log .= '- EXIF orientation = 5 : horizontal flip + 90 rotate left';
    break;
  case 6:
    $auto_rotate = 270;
    $this->log .= '- EXIF orientation = 6 : 270 rotate left';
    break;
  case 7:
    $auto_flip = 'h';
    $auto_rotate = 270;
    $this->log .= '- EXIF orientation = 7 : horizontal flip + 270 rotate left';
    break;
  case 8:
    $auto_rotate = 90;
    $this->log .= '- EXIF orientation = 8 : 90 rotate left';
    break;
  default:
    $this->log .= '- EXIF orientation = '.$orientation.' : unknown';
    break;
}

Hope you can use it!
This will make the uploadtimes with image-rotation a lot faster!Reply
Re: image_auto_rotate is very slow new!
by colin, 1 year, 7 months ago
Thank you very much. Tbh, I have no spre time right now to implement and test it, but I have written down your code, and will try to integrate it as soon as possible.Reply