I am using the following code.
$im = imagecreatefrompng('1.png');
imagefilter($im, IMG_FILTER_GRAYSCALE);
imagefilter($im, IMG_FILTER_CONTRAST, -40);
....
imagedestroy($im);
Now, I have to create the image again to apply different filter.
$im = imagecreatefrompng('1.png');
imagefilter($im, IMG_FILTER_GRAYSCALE);
imagefilter($im, IMG_FILTER_COLORIZE, 100,50,0);
....
imagedestroy($im);
Do i need to destroy and create that image every time to apply a new effect?
Or can we use it by removing the previous filter?
Related
I am writing a python script that creates/updates views in the dataset from an SQL script.
I am wondering if it is possible for me to check if an authorized view has been created in the dataset. If so and I wish to delete it, is there a python method that does so?
For authorized views we need to create a separate dataset and give access to it. Next step is to create view in that dataset and everyone who has access to dataset gets access to the view.
I can see following possibilities to remove authorized view:
Remove AccessEntry from dataset.
Remove view from dataset.
Remove the whole dataset with all views and access given to it.
Let's take a look for official documentation, where you can find Python example. We need to perform two operations. Firstly unauthorize the view to remove access to the source dataset, then remove access controls to the dataset containing the view. We need to use remove() method:
# Unauthorize the view to access the source dataset
access_entries = source_dataset.access_entries
access_entries.remove(
bigquery.AccessEntry(None, 'view', view.reference.to_api_repr())
)
source_dataset.access_entries = access_entries
source_dataset = client.update_dataset(
source_dataset, ['access_entries'])
# Remove access controls to the dataset containing the view
analyst_group_email = 'data_analysts#example.com'
access_entries = shared_dataset.access_entries
access_entries.remove(
bigquery.AccessEntry('READER', 'groupByEmail', analyst_group_email)
)
shared_dataset.access_entries = access_entries
shared_dataset = client.update_dataset(
shared_dataset, ['access_entries'])
Additionally, here you can find multiline for-loop example, which removes the access:
source_dataset = bigquery_client.get_dataset(dataset_id)
access_entries = source_dataset.access_entries
for access_entry_data in access_entries:
dict_auth = access_entry_data.entity_id
if isinstance(dict_auth, dict):
if dict_auth['tableId'] == resource:
idx = access_entries.index(access_entry_data)
access_entries.pop(access_entries.index(access_entry_data))
source_dataset.access_entries = access_entries
source_dataset = bigquery_client.update_dataset(source_dataset, ['access_entries'])
To read more about AccessEntry, please visit official documentation.
I have a FileField in a Django Model. Some entries in this FileField are set to <ImageFieldFile: null>.
The rest of the Model table are blank or actual images. I need to clean this table so that these erroraneous entries are also changed to blank, as this is not acceptable in my DRF API.
Get all the image instance.
objs =myclassmodel.objects.all() //just assuming this
for obj in objs:
obj.image = ""
obj.save()
It will you if understand it right.
i would like to read some images with scilab and i use the function imread like this
im01=imread('kodim01t.jpg');
im02=imread('kodim02t.jpg');
im03=imread('kodim03t.jpg');
im04=imread('kodim04t.jpg');
im05=imread('kodim05t.jpg');
im06=imread('kodim06t.jpg');
im07=imread('kodim07t.jpg');
im08=imread('kodim08t.jpg');
im09=imread('kodim09t.jpg');
im10=imread('kodim10t.jpg');
i would like to know if there is a way to do something like below in order to optimize the
for i = 1:5
im&i=imread('kodim0&i.jpg');
end
thanks in advance
I see two possible solutions using execstr or using some kind of list/matrix
Execstr
First create a string of the command to execute with msprintf and then execute this with execstr. Note that in the msprintf conversion the right amount of leading zeros are inserted by %0d format specifier descbribed here.
for i = 1:5
cmd=msprintf('im%d=imread(\'kodim%02d.jpg\');', i, i);
execstr(cmd);
end
List/Matrix
This is probably the more intuitive option using a indexable container such as list.
// This list could be generated using msprintf from example above
file_names_list = list("kodim01t.jpg", "kodim02t.jpg" ,"kodim03t.jpg");
// Create empty list to contain images
opened_images = list();
for i=1:length(file_names_list)
// Open image and insert it at end of list
opened_images($+1) = imread(file_names_list[i]);
end
I've been digging around a little trying to figure out how I should locate the "tweet_id" in my #savedtweets table and then locate that same "tweet_id" in my #newtweets table from a controller, so far I'ved tried something like this;
CONTROLLER
#stweet = Savedtweet.find(params[:id])
#newtweet = Newtweet.where(:tweet_id => #stweet.tweet_id)
#newtweet.status = 'new'
#newtweet.save
Basically I need to change the string "saved" in my Newtweets table to "new" based on the current Savedtweet ID. I just can't figure it out. If I do the following in console;
#stweet = Savedtweet.first
#newtweet = Newtweet.where(:tweet_id => #stweet.tweet_id)
It finds the right one. I've got to be close just not there yet. :)
You could do:
Newtweet.find_by_tweet_id(#stweet.tweet_id).update_attribute(:status, 'new')
The reason your code isn't working is because Newtweet.where() returns an array of objects. It should be Newtweet.where().first, though Newtweet.find_by_tweet_id is the preferred method.
Im using custom filtering for my datatable using the method:
$.fn.dataTableExt.afnFiltering.push("custom filter function");
This function adds a filter to my datatable.
The problem is that when I use ajax to create an other datatable object, this filter persists and is applied to this other table that should have nothing to do with this filter. How do I clear the filter or bind it to the first datatable only?
if you make a push on $.fn.dataTableExt.afnFiltering, it means it's an array. So when you receive your data, you can remove the filter reference in this array by using :
delete $.fn.dataTableExt.afnFiltering[index or key];
this method will set the element to undefined
or by using the splice method in javascript.
$.fn.dataTableExt.afnFiltering.splice(index,1);
this method will remove the element from the array.
so
var index = $.fn.dataTableExt.afnFiltering.indexOf("custom filter function");
$.fn.dataTableExt.afnFiltering.splice(index,1);
should resolve your problem
(you can have precision here Javascript - remove an array item by value as indexOf is not supported by IE<9)
If you are going to use the 1.10+ version of the datatable in the future, the use of the search plug-in document is shown below:
Search plug-in development
To reset the filter for version 1.10+, simply add any of the following;
$.fn.dataTable.ext.search = [];
$.fn.dataTable.ext.search.pop();
after this blocks you can add;
table.draw();
$.fn.dataTableExt.afnFiltering.pop();
credit to #DrewT
As mentioned from #kthorngren, there is no build in way of tracking, if or how much custom searches are active.
If you are sure, that there is only one custom search is active a
$.fn.dataTableExt.afnFiltering.pop();
will work - there is big BUT:
$.fn.dataTable.ext.search is an array which contains the search settings for custom search and for searchPanes.
An erasing of this array with $.fn.dataTable.ext.search = []; or two pop()'s, allthough there is only one custom search is active --> will brake searchPanes.
e.g. if you have three panes active, this would mean:
$.fn.dataTable.ext.search[0] -> SearchPane Col1
$.fn.dataTable.ext.search[1] -> SearchPane Col2
$.fn.dataTable.ext.search[2] -> SearchPane Col3
$.fn.dataTable.ext.search[3] -> Custom Search -> safe to delete
$.fn.dataTable.ext.search[4] -> Custom Search -> safe to delete
Following code does the job in my case:
let lenOfSearchPanes = dt.settings()[0]._searchPanes.c.columns.length;
let lenOfSearchArr = $.fn.dataTable.ext.search.length;
let diff = lenOfSearchArr - lenOfSearchPanes
if (diff > 0) {
$.fn.dataTable.ext.search = $.fn.dataTable.ext.search.slice(0, -diff);
}