I've been using a great class to manipulate images for a number of years.
class.upload.php
Currently I need to be able to determine if the image is side wards and rotate it, to vertical position. I understand that I can use
$handle->image_auto_rotate = true;
But for some reason I'm not having much luck. The image I was testing with is JPEG.
What am I missing?
Use: $handle->image_rotate = '90';
Related
I use the imagine library to manage the sizing of images.
$imagine = new Imagine\Imagick\Imagine();
$imagine->open($file)
->thumbnail(new Imagine\Image\Box(1000, 2000), Imagine\Image\ImageInterface::THUMBNAIL_INSET)
->save($file);
I use the following function to generate a thumbnail with proper dimensions. However, on some images (only), the images turn over 90 degrees (here an image of 3024x4032). Do you know how to keep the orientation ? (I did not find an option in the documentation).
Thanks in advance
I'm trying to downsample every image that I consider large for my site on uploading, so when a user tries to upload an image I firstly check if it has an acceptable resolution, otherwise I want to drop this resolution. The code I use for this is:
if ($image->isValid()){
$imagick = new \Imagick();
$imagick->readImage($image);
$resolution = $imagick->getImageResolution();
$resolution_x = $resolution['x'];
$resolution_y = $resolution['y'];
if ($resolution_x > 30 && $resolution_y > 30){
$imagick->setImageResolution($resolution_x,$resolution_x);
$imagick->resampleImage($resolution_x/2,$resolution_x/2,\imagick::FILTER_CATROM,1);
}
$imagick->writeImage($uploadDir.$path);
}
This code was supposed to set the resolution of an image with resolution 300 dpi for example to 150dpi. Instead of this, the resolution remains 300 dpi and the image dimensions drop to the half of their previous values (e.g an image (1200x800) turns into (600x400)). Am I missing something about the functionality of Imagick::resampleImage or is there any error in my code? I've done a lot of search before post this question and tried lot of different ways to succeed my goal using Imagick but I cannot get it done!
The 'resolution' in the setImageResolution and getImageResolution functions refer to the dots per inch setting of the image, which is a hint to printers of what size to print the image i.e. how many dots per inch it should be printed at.
It does not affect the pixel dimensions of the image, and so does not have a noticeable effect on the image on a computer, which does not use the DPI setting to render an image.
You want to use either just $imagick->getImageWidth() and $imagick->getImageHeight() or $imagick->getImageGeometry() to get the pixel size of the image, and then resample it based on those pixel dimension, rather than the printer hint setting.
It sounds like the resolution values should be the same in both setImageResolution and resampleImage. Have you tried this yet?
$imagick->setImageResolution($resolution_x/2,$resolution_x/2);
I'm trying to finish up my image uploader that utilizes imagick for the handling of various image types. One thing specifically that I'm trying to get working is the conversion of jpeg files to progressive jpeg. I've tried the following code below, but when I view the images that get output in irfranview, the jpeg are not progressive. Any ideas? This literally must work by Monday.. Please help
foreach ($thumbnailScaleWidths as $thumbnailScaleWidth) {
$thumbnail = new imagick($uploadedFile['tmp_name']);
$thumbnailDimensions = $thumbnail->getImageGeometry();
$thumbnailWidth = $thumbnailDimensions['width'];
$thumbnailHeight = $thumbnailDimensions['height'];
$thumbnailScaleHeight = ($thumbnailScaleWidth / $thumbnailWidth) * $thumbnailHeight;
$thumbnail->thumbnailImage($thumbnailScaleWidth, $thumbnailScaleHeight);
$thumbnail->setImageInterlaceScheme(Imagick::INTERLACE_PLANE);
$thumbnail->writeImages($_SERVER['DOCUMENT_ROOT'] . "/Resources/Media/$userId/$internalName-$thumbnailScaleWidth.$fileType", true);
}
Any ideas as to why this isn't outputting progressive jpegs?
I know this thread is old but here is an answer that might save time to others in the future.
So since you are reading an image from file, you should use the following method instead:
Imagick::setInterlaceScheme
It seems that Imagick::setImageInterlaceScheme will work only when Imagick is used to generate an image by itself...
not sure where but I came across as image hosting site that allows you to upload your image in a large format or to sharpen it.
I personally do not recall or know of any functions of GD library to sharpen image which might just be a different word for quality being up-ed.
If some one knows of a function to sharpen images please tell me since personally I am not aware of such functions neither in Image Magic and/or GD Library.
Thanks in advance
You can use imageconvolution in GD with a sharpen mask. From http://adamhopkinson.co.uk/blog/2010/08/26/sharpen-an-image-using-php-and-gd/:
PHP and GD can sharpen images by providing a matrix to imageconvolution:
// create the image resource from a file
$i = imagecreatefromjpeg('otter.jpg');
// define the sharpen matrix
$sharpen = array(
array(0.0, -1.0, 0.0),
array(-1.0, 5.0, -1.0),
array(0.0, -1.0, 0.0)
);
// calculate the sharpen divisor
$divisor = array_sum(array_map('array_sum', $sharpen));
// apply the matrix
imageconvolution($i, $sharpen, $divisor, 0);
// output the image
header('Content-Type: image/jpeg');
imagejpeg($i);
You'd use imageconvolution() with a matrix that corresponds to a sharpen filter. Details in this comment on the PHP site: http://php.net/manual/en/ref.image.php#56144
I haven't tried it, but this looks like what you're looking for, as far as ImageMagick goes.
In GD library of php having a file with path
lib/PHPImageWorkshop/Core/ImageWorkshopLayer.php
Please go to save public function and you can change the imageQuality upto 100.
make sure which type of image you want to create.
Hope this will help you.
I have a site where users can upload images. I process these images directly and resize them into 5 additional formats using the CodeIgniter Image Manipulation class. I do this quite efficiently as follow:
I always resize from the previous format, instead of from the original
I resize using an image quality of 90% which about halves the file size of jpegs
The above way of doing things I implemented after advise I got from another question I asked. My test case is a 1.6MB JPEG in RGB mode with a high resolution of 3872 x 2592. For that image, which is kind of borderline case, the resize process in total takes about 2 secs, which is acceptable to me.
Now, only one challenge remains. I want the original file to be compressed using that 90% quality but without resizing it. The idea being that that file too will take half the file size. I figured I could simply resize it to its' current dimensions, but that doesn't seem to do anything to the file or its size. Here's my code, somewhat simplified:
$sourceimage = "test.jpg";
$resize_settings['image_library'] = 'gd2';
$resize_settings['source_image'] = $sourceimage;
$resize_settings['maintain_ratio'] = false;
$resize_settings['quality'] = '90%';
$this->load->library('image_lib', $resize_settings);
$resize_settings['width'] = $imagefile['width'];
$resize_settings['height'] = $imagefile['height'];
$resize_settings['new_image'] = $filename;
$this->image_lib->initialize($resize_settings);
$this->image_lib->resize();
The above code works fine for all formats except the original. I tried debugging into the CI class to see why nothing happens and I noticed that the script detects that the dimensions did not change. Next, it simply makes a copy of that file without processing it at all. I commented that piece of code to force it to resize but now still nothing happens.
Does anybody know how to compress an image (any image, not just jpegs) to 90% using the CI class without changing the dimensions?
I guess you could do something like this:
$original_size = getimagesize('/path/to/original.jpg');
And then set the following options like this:
$resize_settings['width'] = $original_size[0];
$resize_settings['height'] = $original_size[1];
Ok, so that doesn't work due to CI trying to be smart, the way I see it you've three possible options:
Rotate the Image by 360ยบ
Watermark the Image (with a 1x1 Transparent Image)
Do It Yourself
The DIY approach is really simple, I know you don't want to use "custom" functions but take a look:
ImageJPEG(ImageCreateFromString(file_get_contents('/path/to/original.jpg')), '/where/to/save/optimized.jpg', 90);
As you can see, it's even more simpler than using CI.
PS: The snippet above can open any type of image (GIF, PNG and JPEG) and it always saves the image as JPEG with 90% of quality, I believe this is what you're trying to archive.