How to extract the image from this https://www.google.com/maps/#45.8118462,15.9725486,3a,75y/data=!3m7!1e2!3m5!1sAF1QipOH6lgU7bug2ndyW-9-Uq0kgKqcKDtnGei2N5Qo!2e10!6shttps:%2F%2Flh5.googleusercontent.com%2Fp%2FAF1QipOH6lgU7bug2ndyW-9-Uq0kgKqcKDtnGei2N5Qo%3Dw150-h150-k-no-p!7i3024!8i4032
(If the link disappears let me describe how to reproduce the question. Find any shop on Google Maps that has the "shop title image" appearing in the shop details on the left side when you click on that shop. Click on that image to expand it across the whole viewport.)
I found the <canvas> element that I guess contains the image. I tried to do .getContext('2d') on that canvas element, but I keep getting null.
If you are getting null when doing getContext("2d") it's because an other type of context was created already, in this case, a "webgl" one.
To convert that canvas to a new image, you'd normally call canvas.toBlob() (whatever the context type).
And if you need to crop that canvas content, you'd draw it on an other canvas.
But since they did not prevent the WebGL context to throw away its drawing buffer (by passing preserveDrawingBuffer in the getContext call), you'll only get a transparent image back from it.
Anyway none of these methods will retrieve the original image, but they will create a new image entirely (probably of lesser quality, and bigger in size). To retrieve the original image, check the network tab of your dev tools, or if you need to do it programmatically, inject a script that will spoof all fetch, XHR and HTMLImageElement objects in order to log their resource URL. But that becomes dirty.
Related
I'm trying to replace an image in a Google Slide by a smaller version of it (in terms of bytes).
The smaller image should be displayed exactly the same way than the older.
But when my original image was croped, I cannot reproduce it with the new one.
What I'm doing is simple (I'm using this replace method)
let image = page.getImages()[0];
let newImageUrl = optimize(image.getContentUrl()); // API call to get an optimized image. newImage will have the same width and height
image.replace(newImageUrl, true);
A visual example.
Here is my slide before (pay attention to the "Quick" logo at the bottom right corner)
And here is the result after replacing it (you can see that the bounding box is the same, it takes the same space in the slide, but the image itself is lower)
How can I reproduce the croping that I've initially done in my slide with that button ?
Thanks
Issue:
As mentioned in comments, crop properties are currently read-only, so this cannot be done. Here are possible workarounds: https://stackoverflow.com/a/63256489, https://stackoverflow.com/a/64040404, https://stackoverflow.com/a/67309702.
Feature request:
There's a feature request in Issue Tracker. Anyone interested in this, consider starring it:
Why are Image Crop Properties read only
I'm creating a mobile web application (HTML5/JavaScript/CSS only) that allows a user to take a picture. The picture from the camera is then loaded into a canvas HTML element. The user may rotate their phone when taking a photo so ultimately I want to rotate the output appropriately. Is there a way in a web page only to determine which degree a user has rotated when taking a picture? I'm not simply talking about whether they are in landscape mode. I'm meaning if you hold your phone straight up in portrait mode face it down at your desk (its now parallel with your desk) and then rotate it to landscape. This will not trigger an orientation change, but you will now be holding your phone in a "landscape" position if that makes sense. This will be a common way users will be taking the photos. I want to be able to rotate the image appropriately when uploading it.
Thank you
Is there a way in a web page only to determine which degree a user has rotated when taking a picture?
Yes there is! When photos are taken, they contain metadata - information about the image. This is called EXIF data.
It tells you things like the make of camera, whether the flash went off, and - usefully for you - the orientation of the camera.
If you are using JavaScript to draw the image onto the canvas, I can recommend BlueImp's JavaScript Load Image Library
Once you have loaded the image, you'll be able to do a call like:
var orientation = data.exif.get('Orientation');
That will tell you which way the camera was held when the photo was taken. Depending on the phone, you may also get rotation data, GPS data, compass heading, etc.
We're using google maps and want to keep our traffic to that site to a minimum. At present we have an <li> element that contains an href to a generated maps.google.com URL. That link can change based on the orientation of the device-- the same map address, but we use a resized map to fit the screen appropriately.
We're storing the portrait and landscape google maps' <href> values to keep from regenerating them every time the device is reoriented. Then, on every orientation change we flip the <li>'s html property using jQuery like this:
//on an orientation change...
if (window.orientation == "portrait") {
$(#mapLi).html(portraitMapHref);
}
else {
$(#mapLi).html(landscapeMapHref);
}
The google API generates the hrefs and the embedded <img> tags for us on the page load, and the first time an orientation change occurs. This of course leads to a connection to maps.google.com.
When we swap back and forth using the .html function with the cached hrefs there doesn't appear to be a simultaneous call to maps.google.com, which is what we're after, but I wondered if this is due to browser caching or the nature of the .html function in jqm? I thought that swapping the html value in that element would trigger a call to the maps.google.com address. Should it not, or are we getting lucky with browser caching?
It's not clear what exactly you store in portraitMapHref and landscapeMapHref, but I guess you store nodes.
In this case when you use $.html(), the new content will replace the current content, but the old content(node) will not be deleted, it's still a node, no matter if it's attached to the DOM or not.
There is nothing to load when you re-use the replaced node.
I am developing an Windows Forms application using VB.NET that offers the user to lookup addresses on Google Maps through a Web Browser. I can also successfully show the directions between two points to the user, as well as allow the user to drag the route as he/she pleases. My question now is - is it possible for me to get the lattitude/longitude information of the route, i.e. the overview_polyline array of encoded lattitude/longitude points and save it to e.g. a text file on my computer? Or is it possible to get a list of all the addresses located both sides of the route over the entire length of the route, and then save the data to a file on my computer? I'm using HTML files to access and display the Google Maps data in the Web Browser item.
Thank you
This is actually pretty simple if your just looking for the screen coordinates.
// this probably should be in your form initialization
this.MouseClick += new MouseEventHandler(MouseClickEvent);
void MouseClickEvent(object sender, MouseEventArgs e)
{
// do whatever you need with e.Location
}
if your strictly looking for the point in the browser, you need to consider the functions
browser.PointToClient();
browser.PointToScreen();
So, this method is usable if you know exactly where your form is (easy to get its coords) and where you webbrowser control is (easy to get coords of this as well since it's just a control in your form) and then, as long as you know how many pixels from the left or right, and from the top or bottom the image will be displayed, once you get the global mouse click coords (which is easy) you can predict where it was clicked on the image.
Alternatively, there are some scarier or uglier ways to do it here...
You can use the ObjectForScripting property to embed code to do this in the webbrowser. It's ugly to say the least. MSDN has some documentation on the process here: http://msdn.microsoft.com/en-us/library/system.windows.forms.webbrowser.objectforscripting.aspx
Because its really ugly, maybe a better solution is to use AxWebBrowser - it's ugly too but not so scary.
In addition, I found this post of someone wanting to do it on a pdf document, and a MSFT person saying its not possible, but really what he is trying to say is that it isn't built in, even with a pdf document its still possible to predict with high to certain accuracy where it was clicked if you use the first method i described. Here is the post anyway: http://social.msdn.microsoft.com/Forums/en/csharpgeneral/thread/2c41b74a-d140-4533-9009-9fcb382dcb60
However, it is possible, and there are a few ways to do it, so don't get scared from that last link I gave ya.
Also, this post may help if you want to do it in javascript:
http://www.devx.com/tips/Tip/29285
Basically, you can add an attribute on the image through methods available in the webbrowser control, you can add something like onclick="GetCoords();" so when it is clicked, the JavaScript function will get the coords, and then you can use javascript to place the values in a hidden input field (input type="hidden") which you can add through the webbrowser control, or if there is one already on the page, you can use that. So, once you place the coords using javacript into that input field, you can easily grab the value in that using the webbrowser control, eg:
webbrowser1.document.getElementById("myHiddenInputField").value
That will get the value in that field, which you've set through JavaScript. Also, the "GetCoords()" function i mentioned is called SetValues() in the javascript method link i provided above (in the devx.com site) but I named it GetCoords because it makes more sense and didn't want to confuse you with the actual name they used, you can change this to any name you want of course. Here is the javascript they were using, this only gets the coords into a variable, doesn't put it into a hidden input field, we will need to do that in addition (at the end of the javascript SetValues/GetCoords function).
function SetValues()
{
var s = 'X=' + window.event.clientX + ' Y=' + window.event.clientY ;
document.getElementById('divCoord').innerText = s;
}
These guys are just saving it inside a div element, which is visible to users, but you can make the div invisible if you want to use a div field, there is no advantage or disadvantage in doing that, you would just need to set the visible property to false using javascript or css, but still, it is easier to use a hidden input field so you don't need to mess with any of that.
Let me know how you get along.
I have been searching - am thinking what I want to do is not possible but thought I would check.
I have a few canvasses on an HTML page as follows: (these are IDs below)
canvasMain - this is going to display
a large version of an image
canvasThumbnail1 - this is going to
display a thumbnail image
canvasThumbnail2 - same as
above...etc
I have it working where I paint the canvasMain with the contents of the thumbnail. The problem is since the canvas is immediate it is copying the pixels as they are over to the canvasMain from canvasThumbnail. This is resulting in an enlarged pixelated image.
What I want to do is click on one of the canvasThumbnails and be able to grab the Image.src property as a string and then pull that into canvasMain instead of actually copying the pixels over from one canvas to another. Essentially just grab the address (local or say on Flickr) from where I can pull in the image. Pulling an image in to a canvas seems to scale it nicely.
From what I have seen I do not think that Image.src value is accessible through the 2d context. I enumerated through its properties and have only found nested objects or native code returns.
I figured that if I clicked on the canvasThumbnail, and then used (this) to get a reference to that canvas element and then grab the 2dcontext of that canvas I may be able to use a property of that context to get a string that represents the value of the Image.src.
Any ideas?
Thanks
Somehow you painted the image onto canvasThumbnail1, presumably from a (high resolution) Image element.
The canvasThumbnail1, or any canvas for that matter, has no memory on things painted on it. So if you paint a large Image onto a tiny canvasThumbnail, the high-resolution data does not exist on that tiny canvas. To get it you must use the original image again, or else you must paint to a larger canvas from the start.
In other words, instead of painting the thumbnail onto the main, you need to repaint Image element (that you used to make the thumbnail) onto the main.