HTML to Image in Java

This page describes how to convert web pages and HTML to images in Java using the Pdfcrowd API. The API is easy to use and the integration takes only a few of lines of code.

Samples

Wikipedia

Stack Overflow

Installation

Download pdfcrowd-5.7.0-java.zip, unzip it and copy pdfcrowd-5.7.0.jar to your CLASSPATH.

We also offer other installation options (Maven, GitHub).

Authentication

Authentication is needed in order to use the Pdfcrowd API. The credentials used for accessing the API are your Pdfcrowd username and the API key.

You can try out the API without registration using the following demo credentials:

Username: demo
API key: ce544b6ea52a5621fb9d55f8b542d14d

To get your personal API credentials, you can start a free API trial or buy the API license.

Getting Started

Enter a web page or upload an HTML file to get an image preview and integration code that you can copy and paste to your application.

Or you can choose from the examples below and adapt the code to your needs. You can also interactively explore the API in the API Playground.

Examples

Convert a web page to a PNG file

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // create the API client instance
            Pdfcrowd.HtmlToImageClient client =
                new Pdfcrowd.HtmlToImageClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

            // configure the conversion
            client.setOutputFormat("png");

            // run the conversion and write the result to a file
            client.convertUrlToFile("http://www.example.com", "example.png");
        }
        catch(Pdfcrowd.Error why) {
            // report the error
            System.err.println("Pdfcrowd Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
        catch(IOException why) {
            // report the error
            System.err.println("IO Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
    }
}

Convert a web page to in-memory PNG

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws Pdfcrowd.Error {
        try {
            // create the API client instance
            Pdfcrowd.HtmlToImageClient client =
                new Pdfcrowd.HtmlToImageClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

            // configure the conversion
            client.setOutputFormat("png");

            // run the conversion and store the result into the "image" variable
            byte[] image = client.convertUrl("http://www.example.com");

            // at this point the "image" variable contains PNG raw data and
            // can be sent in an HTTP response, saved to a file, etc.
        }
        catch(Pdfcrowd.Error why) {
            // report the error
            System.err.println("Pdfcrowd Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
    }
}

Convert a web page and write the resulting PNG to an output stream

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // create the API client instance
            Pdfcrowd.HtmlToImageClient client =
                new Pdfcrowd.HtmlToImageClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

            // configure the conversion
            client.setOutputFormat("png");

            // create an output stream for the conversion result
            FileOutputStream outputStream = new FileOutputStream("example.png");

            // run the conversion and write the result into the output stream
            client.convertUrlToStream("http://www.example.com", outputStream);

            // close the output stream
            outputStream.close();
        }
        catch(Pdfcrowd.Error why) {
            // report the error
            System.err.println("Pdfcrowd Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
        catch(IOException why) {
            // report the error
            System.err.println("IO Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
    }
}

Convert a local HTML file to a PNG file

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // create the API client instance
            Pdfcrowd.HtmlToImageClient client =
                new Pdfcrowd.HtmlToImageClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

            // configure the conversion
            client.setOutputFormat("png");

            // run the conversion and write the result to a file
            client.convertFileToFile("/path/to/MyLayout.html", "MyLayout.png");
        }
        catch(Pdfcrowd.Error why) {
            // report the error
            System.err.println("Pdfcrowd Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
        catch(IOException why) {
            // report the error
            System.err.println("IO Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
    }
}

Convert a local HTML file to in-memory PNG

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws Pdfcrowd.Error {
        try {
            // create the API client instance
            Pdfcrowd.HtmlToImageClient client =
                new Pdfcrowd.HtmlToImageClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

            // configure the conversion
            client.setOutputFormat("png");

            // run the conversion and store the result into the "image" variable
            byte[] image = client.convertFile("/path/to/MyLayout.html");

            // at this point the "image" variable contains PNG raw data and
            // can be sent in an HTTP response, saved to a file, etc.
        }
        catch(Pdfcrowd.Error why) {
            // report the error
            System.err.println("Pdfcrowd Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
    }
}

Convert a local HTML file and write the resulting PNG to an output stream

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // create the API client instance
            Pdfcrowd.HtmlToImageClient client =
                new Pdfcrowd.HtmlToImageClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

            // configure the conversion
            client.setOutputFormat("png");

            // create an output stream for the conversion result
            FileOutputStream outputStream = new FileOutputStream("MyLayout.png");

            // run the conversion and write the result into the output stream
            client.convertFileToStream("/path/to/MyLayout.html", outputStream);

            // close the output stream
            outputStream.close();
        }
        catch(Pdfcrowd.Error why) {
            // report the error
            System.err.println("Pdfcrowd Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
        catch(IOException why) {
            // report the error
            System.err.println("IO Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
    }
}

Convert a string containing HTML to a PNG file

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // create the API client instance
            Pdfcrowd.HtmlToImageClient client =
                new Pdfcrowd.HtmlToImageClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

            // configure the conversion
            client.setOutputFormat("png");

            // run the conversion and write the result to a file
            client.convertStringToFile("<html><body><h1>Hello World!</h1></body></html>", "HelloWorld.png");
        }
        catch(Pdfcrowd.Error why) {
            // report the error
            System.err.println("Pdfcrowd Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
        catch(IOException why) {
            // report the error
            System.err.println("IO Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
    }
}

Convert a string containing HTML to in-memory PNG

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws Pdfcrowd.Error {
        try {
            // create the API client instance
            Pdfcrowd.HtmlToImageClient client =
                new Pdfcrowd.HtmlToImageClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

            // configure the conversion
            client.setOutputFormat("png");

            // run the conversion and store the result into the "image" variable
            byte[] image = client.convertString("<html><body><h1>Hello World!</h1></body></html>");

            // at this point the "image" variable contains PNG raw data and
            // can be sent in an HTTP response, saved to a file, etc.
        }
        catch(Pdfcrowd.Error why) {
            // report the error
            System.err.println("Pdfcrowd Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
    }
}

Convert a string containing HTML and write the resulting PNG to an output stream

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // create the API client instance
            Pdfcrowd.HtmlToImageClient client =
                new Pdfcrowd.HtmlToImageClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

            // configure the conversion
            client.setOutputFormat("png");

            // create an output stream for the conversion result
            FileOutputStream outputStream = new FileOutputStream("HelloWorld.png");

            // run the conversion and write the result into the output stream
            client.convertStringToStream("<html><body><h1>Hello World!</h1></body></html>", outputStream);

            // close the output stream
            outputStream.close();
        }
        catch(Pdfcrowd.Error why) {
            // report the error
            System.err.println("Pdfcrowd Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
        catch(IOException why) {
            // report the error
            System.err.println("IO Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
    }
}

Get info about the current conversion

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // create the API client instance
            Pdfcrowd.HtmlToImageClient client =
                new Pdfcrowd.HtmlToImageClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

            // configure the conversion
            client.setOutputFormat("png");
            client.setDebugLog(true);

            // run the conversion and write the result to a file
            client.convertFileToFile("/path/to/MyLayout.html", "MyLayout.png");
            
            // print URL to the debug log
            System.out.println("Debug log url: " + client.getDebugLogUrl());
            
            // print the number of available conversion credits in your account
            System.out.println("Remaining credit count: " + client.getRemainingCreditCount());
            
            // print the number of credits consumed by the conversion
            System.out.println("Consumed credit count: " + client.getConsumedCreditCount());
            
            // print the unique ID of the conversion
            System.out.println("Job id: " + client.getJobId());
            
            // print the size of the output in bytes
            System.out.println("Output size: " + client.getOutputSize());
        }
        catch(Pdfcrowd.Error why) {
            // report the error
            System.err.println("Pdfcrowd Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
        catch(IOException why) {
            // report the error
            System.err.println("IO Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
    }
}

Integration Examples

The API can be easily integrated into your environment. You can have our interactive API Playground autogenerate the integration code for you:

Common Customizations

The API lets you convert a web page, a local HTML file, or a string containing HTML. The result of the conversion can be stored to a local file, to a stream object or to a variable. See the conversion input section for more details.

The best way to start with the API is to choose one of the examples and once you get it working, you can further customize the code. You can find the most common customizations in the table below.

Image size	Set image dimensions with setScreenshotWidth and setScreenshotHeight.
Image format	Specify a different output image format with setOutputFormat.
Hide or remove elements	You can use the following classes in your HTML code to hide or remove elements from the output: `pdfcrowd-remove` - sets `display:none!important` on the element `pdfcrowd-hide` - sets `visibility:hidden!important` on the element Learn about other options.
Use @media print	You can switch to the print version of the page (if it exists) with setUsePrintMedia.
Run custom JavaScript	You can use setOnLoadJavascript or setCustomJavascript to alter the HTML contents with a custom JavaScript. In addition to the standard browser APIs, the custom JavaScript code can use helper functions from our JavaScript library .
Custom CSS styling	You can alter CSS styling used during conversion with a custom JavaScript or using the `pdfcrowd-body` CSS class, which is automatically set on the HTML <body> element. You can, for example, set the H1 height to 48px by adding the following line to your CSS: `.pdfcrowd-body h1 { font-size: 48px; }`

Template Rendering

The API enables rendering of HTML templates. The template syntax is based on the Jinja template rendering engine.

The most common constructs are:

Data rendering: Invoice: {{ invoice.number }}
For loop: {% for invoice in invoices %} ... {% endfor %}
If statement: {% if invoice.total > 100 %} ... {% endif %}
Data filter: {{ invoice.to.first_name|capitalize }}

The supported input data formats are JSON, XML, CSV and YAML. The data can be uploaded from a file or from a string variable.

Supported template filters: capitalize, center, default, escape, first, forceescape, format, indent, join, last, length, list, lower, replace, reverse, safe, slice, sort, string, striptags, title, trim, truncate, unique, upper, wordcount, wordwrap.

Template Rendering Examples

Create Image from JSON data

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // create the API client instance
            Pdfcrowd.HtmlToPdfClient client =
                new Pdfcrowd.HtmlToPdfClient("{{ user_name }}", "{{ api_key }}");

            // configure the conversion
            client.setDataString("{\n" +
                "    \"name\": \"World\",\n" +
                "    \"product\": \"Pdfcrowd API\"\n" +
                "}");

            // run the conversion and write the result to a file
            client.convertStringToFile("Hello {{ name }} from {{ product }}", "output.pdf");
        }
        catch(Pdfcrowd.Error why) {
            // report the error
            System.err.println("Pdfcrowd Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
        catch(IOException why) {
            // report the error
            System.err.println("IO Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
    }
}

Create Image from XML data

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // create the API client instance
            Pdfcrowd.HtmlToPdfClient client =
                new Pdfcrowd.HtmlToPdfClient("{{ user_name }}", "{{ api_key }}");

            // configure the conversion
            client.setDataString("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
                "<data>\n" +
                "  <name>World</name>\n" +
                "  <product>Pdfcrowd API</product>\n" +
                "</data>");

            // run the conversion and write the result to a file
            client.convertStringToFile("Hello {{ data.name }} from {{ data.product }}", "output.pdf");
        }
        catch(Pdfcrowd.Error why) {
            // report the error
            System.err.println("Pdfcrowd Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
        catch(IOException why) {
            // report the error
            System.err.println("IO Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
    }
}

Create Image from YAML data

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // create the API client instance
            Pdfcrowd.HtmlToPdfClient client =
                new Pdfcrowd.HtmlToPdfClient("{{ user_name }}", "{{ api_key }}");

            // configure the conversion
            client.setDataString("name: World\n" +
                "product: Pdfcrowd API");

            // run the conversion and write the result to a file
            client.convertStringToFile("Hello {{ name }} from {{ product }}", "output.pdf");
        }
        catch(Pdfcrowd.Error why) {
            // report the error
            System.err.println("Pdfcrowd Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
        catch(IOException why) {
            // report the error
            System.err.println("IO Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
    }
}

Create Image from CSV data

import com.pdfcrowd.*;
import java.io.*;

public class ApiTest {
    public static void main(String[] args) throws IOException, Pdfcrowd.Error {
        try {
            // create the API client instance
            Pdfcrowd.HtmlToPdfClient client =
                new Pdfcrowd.HtmlToPdfClient("{{ user_name }}", "{{ api_key }}");

            // configure the conversion
            client.setDataString("name,product\n" +
                "World,Pdfcrowd API");

            // run the conversion and write the result to a file
            client.convertStringToFile("Hello {{ name }} from {{ product }}", "output.pdf");
        }
        catch(Pdfcrowd.Error why) {
            // report the error
            System.err.println("Pdfcrowd Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
        catch(IOException why) {
            // report the error
            System.err.println("IO Error: " + why);

            // rethrow or handle the exception
            throw why;
        }
    }
}

Error Handling

try {
    // call the API 
}
catch(Pdfcrowd.Error why) {
    // print error
    System.err.println("Pdfcrowd Error: " + why);

    // print just error code
    System.err.println("Pdfcrowd Error Code: " + why.getCode());

    // print just error message
    System.err.println("Pdfcrowd Error Message: " + why.getMessage());

    // or handle the error in your way
}

Troubleshooting

List of API Status Codes if an error code is returned.
You can use setDebugLog and getDebugLogUrl to get detailed info about the conversion, such as conversion errors, time, console output.
You can use our JavaScript library to resolve rendering problems, such as missing content or blank pages.
Just use setCustomJavascript with libPdfcrowd.highlightHtmlElements method call to visualize all HTML elements. See the backgrounds example , borders example and helper JavaScript library documentation.
The maximum size of the created image is 65 megapixels. Larger images are cropped vertically.
Take a look at the FAQ section.
Are you missing a feature? Contact us, we look forward to your suggestions.

API Method Reference

Refer for details to the API Method Reference.