I am looking to create a small app that allows a user to create a custom cover for a book. The client doesn't want to just be supplied with what the customer selected but a print ready 300dpi JPEG or PDF.
I know PHP can handle most of this. But the customisation seems to be a bit difficult to get right. I have tried using canvas to create the client side preview, which work ok enough.
Just to see if I'm wasting time trying to recreate the wheel, does anyone know if something like what I need exists already?
Basically it would be something kind of similiar to this but for creating print ready images.
Thanks!
If you're using Canvas for building the editor, for the best results, I'd recommend you re-render the customization on the server using whatever technology fits your need in PHP and not try to take the image they're looking at and make it work somehow by sending it to the server. The DPI will be wrong if you use Canvas in a standard way (it will be at the screen DPI).
For example, if they have the ability to place an image, then just note the coordinates and place the image in a web server created image at 300 DPI. Text, same thing, etc. Yes, it will be extra work, but it should be of higher quality and better consistency.
This would imply that there's a simple serialization format for the representation of the custom cover that is sent to the web server.
You might be able to use SVG, but you'll have to introduce a reliable SVG to PDF conversion and handle fonts. Maybe something like this? (I'm not sure that building an SVG editor would be easier than Canvas based).
Starting from your "work ok enough preview", jsPDF will be able to generate a PDF right from the browser in a breez.
convert the canvas to a image/jpeg (toDataURL will be your best friend)
instanciate a jsPDF object, add the image
output the jsPDF object
Tricky details:
beware your screen displays stuff with 72dpi but print expect 300dpi. So you can up scale your canvas then draw the image within the pdf PDF
beware to Cross Origin Resources: if you are using images outside your domain, you are doomed (or you will need a proxy)
Related
I had created one wordpress site. I want to make all post downloadable by converting it to image.
I tried using canvas but didn't succeed.
Can any one suggest me better working way on wordpress which lets me convert my post to image and make it downloadable?
I want to make post covered with specific div so that i can define size of content to be downloaded.
Like this HTML2CANVAS but I am unable to do.
PS-I have very small size of content in every post
I think your options are
Use some third-party service, such as http://web-capture.net/ or https://www.url2png.com . Most of them, especially the ones with API that you can call on-demand, will cost you, but there are free alternatives.
If you have access to linux console and some basic knowledge about it, the best approach is to run a real browser (if you're using a headless server, use Xvfb) with your post URL and make a screenshot with ImageMagick. You can crop the image to remove browser header etc. A working-grade explanation here http://www.leonardteo.com/2011/07/taking-server-side-screenshots-of-websites/ .
In both cases PHP will be just the trigger, whether it will call third-party API or your local shell script.
I'd also suggest to avoid JPEG format as it doesn't really play well with text. Use PNG instead.
You may try rendering the text with imagettftext() as #Progrock suggested, but this will be a huge pain, because you obviously have text with more than one line. First you need to determine the width of your image, then use imagettfbbox() to roughly estimate how many characters you can fit into one line, split your text into chunks of that size and write then one by one, adding the Y coordinate. Bonus points if you need paragraphs here... Make sure you're using monotype font, because it won't ever work properly with variable-width letters. look through comments here http://php.net/manual/en/function.imagettftext.php.
My advice - stick with the browser :) You can resize the browser window and crop the extra part.
I'm just wondering about a small problem I have. I'm creating a simple website with PHP, HTML and CSS. The user enters the dimensions of a rectangle into a form, and this all works perfectly. However, I'm unsure how to proceed.
The system should then use these dimensions (both stored as separate variables) to draw a rectangle of that size (in cm). The rectangle should be draw in a .pdf document, which the user can then download.
I'm a beginner, so sorry if there's anything wrong with this question.
You're going to want to start with looking into the html5 canvas element for drawing. There's plenty of tutorials online for you. As far as saving to pdf, see this: Convert canvas to PDF good luck.
Take a look at the fpdf extension available for php. Or even better and more consequent: use its unicode capable variant 'tfpdf'.
It allows you to generate a pdf document on the server side in a step by step way. You can control all details of that document. When finished you can return the document to the requesting client.
I am working on a project that consists of a online store, to sell Printed Circuit Boards.
But the hole system will be automated, and will be able to view online the Gerber files (Gerber are the files that has the machine code for the pcb).
I need to choose the best way to "output" this file uploaded by the user, to the webpage. Only for viewing the PCB before buying.
I have done the entire PHP code to process the Gerber, but, I can't decide if the file will be proccesed, and then:
I will save as a PNG file (rendering will be done with the PHP image library {that is a shit}), and if the user zoom, or do anything, it will not be perfect... (I would need to render in a high resolutiong, and would take a lot of space, and also time to load)
Render as an SVG file (Vector file), and show on the HTML as an mbeded element (Does it work on all new browsers? Is it slow to proccess?), The SVG file are awsome in terms of drawing lines...
And the last but not least way to doit, is to create a list of JavaScript commands, that draws on a Canvas Element (I have already implemented this, and works really good, but I don't like to think, that I'm actualy 'rendering' to a code...)
Anyway, what do you think I should use, and if I didn't tought in another way of doing it, please tell me!
Here is an example of the output as Canvas (With the source being a JavaScript function object, that has many drawLine commands):
I'm opting for SVG file, even if it's slower than canvas, but considering that won't be real time drawing process in terms of user interaction with the drawing object it's a good choice. SVG's are actually vectors, hence the images won't be crispy on large images. There are some quite good libraries out there which are working with svg-s like:
http://processingjs.org
http://d3js.org/
http://fabricjs.com/
http://raphaeljs.com/
I think d3 is one of the best. I definitely wont' recommend PHP image library.
Is there any way to programmatically create (client or server side (PHP)) a image from a specific DIV or a complete (web) page? I'm currently creating a web-site for free coupons and the idea is when the end-user clicks on the "Print" button, the app opens a new tab/window with all the selected coupons as a single image (JPG, PNG or etc..) in A4 format ready for printing. Each coupons has it's own data (Article name, price, description etc..) so I need it to be done programmatically over a coupon-template I designed.
I do not ask you to write code for me, just to suggest a solution I could use/develop. If not already exist, I will upload/publish it for free :)
Update: I did it with the PHP GD library :) Still not satisfied with the idea to use Images instead of PDF, because each printing results with different Coupon sizes (images) on different PC's. That's why PDF may would be a better solution. You can see/test it on demo.svikuponi.ba - Just select a few Coupons and click the PRINTAJ button above.
You cannot create image from div for sure but yes you can create dynamic images in php using its gd library.
Following links will help:
http://php.net/manual/en/function.imagecreate.php
http://phptutorial.info/learn/create_images/
Here is a great way for you to create images on the client side: http://smus.com/screen-capture-for-chrome-os
You can take this and create a web app that will work nicely on webkit (for other browsers - I'll look at JS polyfills).
Did anyone mention html2canvas and/or jsfeedback ?
It create a page screenshot completely in javascript, then you can send to the server via ajax..
Obviously, CSS support lack some things.
In php, there is many image related functions like imagettftext() in GD library
for details, check this out http://php.net/manual/en/book.image.php
if GD is not enough, you can try imagick as well
for the template, you can try creating a true color handle in php from your file(image) and add the text part or something else with all kinds of effects and bar codes etc.
but in your case, i would suggest dynamic PDF creation since it would better with formatting instead of plain image, the pdf lib :
http://www.fpdf.org/
you could easily have a background image of your token/voucher and overlay the text using some php variables.
i believe it is possible to create a unique bar-code with php imaging too.
It is possible to get a screenshot from a webpage, but this is quite a hassle. You need to start a webbrowser to render the page and get a screenshot from that.
You are probably better of by parsing some specification and feeding it to a couple of GD or Imagick functions. This is less versatile, but easier to manage.
I am working on a website in which the client wishes to have users upload background images to a printable design, crop to size, add text. Do this to multiple pages then generate a pdf of the 'book'
I am running into the following issues/questions and just need to see where I can start
Are there any PHP developer packages that can do something similar. I have seen jquery crop tools but something also for adding text to an image?
How would I keep the resolution up? If the final cropped with text image needs to be 150dpi, when cropping I am guessing I would have them working on a 72dpi image, then somehow apply the crop and changes to the large image?
If the resolution issue wasn't a big deal I would go about it this way:
Simple image upload
Use jquery to crop photo to correct dimensions
Mess around with gdlibrary and imagettftext() to get the text onto an image (page)
Use something like FPDF to create a pdf from each 'page'
Is this the right way to go about it and any thoughts on the resolution issue. Thank you for any help!
Your primary tool should be ImageMagick. ImageMagick can do the cropping, resizing, scaling, overlay text or graphics, combining images, and apply special effects. A big advantage of using a separate tool instead of PHP's image manipulation tools is that you can do the same transforms in batch through other mechanisms, or even hand the work over to another server to keep the website more responsive. And if you do want to integrate it tightly into the website, you can use the MagickWand For PHP interface.
Cropping does not change DPI, only the dimensions of the image. Scaling, on the other hand, changed both.
You should take a look at Gallery, a GPLed program with some of the functionality you're looking for, and written in PHP.
domPDF is a good tool for converting HTML to a PDF. this way you can use the image they upload as a background image, then put the text over it in any standard HTML tag.
As far as the resolution/dpi issue goes, I'm not sure if there is much you can do outside of changing the size of the image. I would recommend looking into This PHP Library, which has a lot of good tools for manipulating images.
I think with a combination of these tools, you'll be able to create HTML that can make a PDF that's fit to print, and use that.