Image to Image API - Ruby SDK

Convert between various image formats in Ruby using the Pdfcrowd API v2. The API is easy to use and the integration takes only a couple of lines of code.

Installation

Install the client library from rubygems.org
 $ gem install pdfcrowd

You can learn more about other install options here.

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 sign up for the Pdfcrowd API here.

Examples

Convert a local PNG file to a JPEG file
require 'pdfcrowd'

begin
    # create the API client instance
    client = Pdfcrowd::ImageToImageClient.new("your_username", "your_apikey")

    # configure the conversion
    client.setOutputFormat("jpg")

    # run the conversion and write the result to a file
    client.convertFileToFile("/path/to/logo.png", 'logo.jpg')
rescue Pdfcrowd::Error => why
    # report the error
    STDERR.puts "Pdfcrowd Error: #{why}"

    # handle the exception here or rethrow and handle it at a higher level
    raise
end
Convert a local PNG file to in-memory JPEG
require 'pdfcrowd'

begin
    # create the API client instance
    client = Pdfcrowd::ImageToImageClient.new("your_username", "your_apikey")

    # configure the conversion
    client.setOutputFormat("jpg")

    # create output file for conversion result
    output_file = open("logo.jpg", "wb")

    # run the conversion and store the result into an image variable
    image = client.convertFile("/path/to/logo.png")

    # write the image the into the output file
    output_file.write(image)

    # close the output file
    output_file.close()
rescue Pdfcrowd::Error => why
    # report the error
    STDERR.puts "Pdfcrowd Error: #{why}"

    # handle the exception here or rethrow and handle it at a higher level
    raise
end
Convert a local PNG file and write the resulting JPEG to an output stream
require 'pdfcrowd'

begin
    # create the API client instance
    client = Pdfcrowd::ImageToImageClient.new("your_username", "your_apikey")

    # configure the conversion
    client.setOutputFormat("jpg")

    # create output stream for conversion result
    output_stream = open("logo.jpg", "wb")

    # run the conversion and write the result into the output stream
    client.convertFileToStream("/path/to/logo.png", output_stream)

    # close the output stream
    output_stream.close()
rescue Pdfcrowd::Error => why
    # report the error
    STDERR.puts "Pdfcrowd Error: #{why}"

    # handle the exception here or rethrow and handle it at a higher level
    raise
end
Convert url with PNG file to a JPEG file
require 'pdfcrowd'

begin
    # create the API client instance
    client = Pdfcrowd::ImageToImageClient.new("your_username", "your_apikey")

    # configure the conversion
    client.setOutputFormat("jpg")

    # run the conversion and write the result to a file
    client.convertUrlToFile("http://pdfcrowd.com/static/images/logo.png", 'logo.jpg')
rescue Pdfcrowd::Error => why
    # report the error
    STDERR.puts "Pdfcrowd Error: #{why}"

    # handle the exception here or rethrow and handle it at a higher level
    raise
end
Convert url with PNG file to in-memory JPEG
require 'pdfcrowd'

begin
    # create the API client instance
    client = Pdfcrowd::ImageToImageClient.new("your_username", "your_apikey")

    # configure the conversion
    client.setOutputFormat("jpg")

    # create output file for conversion result
    output_file = open("logo.jpg", "wb")

    # run the conversion and store the result into an image variable
    image = client.convertUrl("http://pdfcrowd.com/static/images/logo.png")

    # write the image the into the output file
    output_file.write(image)

    # close the output file
    output_file.close()
rescue Pdfcrowd::Error => why
    # report the error
    STDERR.puts "Pdfcrowd Error: #{why}"

    # handle the exception here or rethrow and handle it at a higher level
    raise
end
Convert url with PNG file and write the resulting JPEG to an output stream
require 'pdfcrowd'

begin
    # create the API client instance
    client = Pdfcrowd::ImageToImageClient.new("your_username", "your_apikey")

    # configure the conversion
    client.setOutputFormat("jpg")

    # create output stream for conversion result
    output_stream = open("logo.jpg", "wb")

    # run the conversion and write the result into the output stream
    client.convertUrlToStream("http://pdfcrowd.com/static/images/logo.png", output_stream)

    # close the output stream
    output_stream.close()
rescue Pdfcrowd::Error => why
    # report the error
    STDERR.puts "Pdfcrowd Error: #{why}"

    # handle the exception here or rethrow and handle it at a higher level
    raise
end
Convert an in-memory PNG to a JPEG file
require 'pdfcrowd'

begin
    # create the API client instance
    client = Pdfcrowd::ImageToImageClient.new("your_username", "your_apikey")

    # configure the conversion
    client.setOutputFormat("jpg")

    # run the conversion and write the result to a file
    client.convertRawDataToFile(open('/path/to/logo.png', 'rb').read(), 'logo.jpg')
rescue Pdfcrowd::Error => why
    # report the error
    STDERR.puts "Pdfcrowd Error: #{why}"

    # handle the exception here or rethrow and handle it at a higher level
    raise
end
Convert an in-memory PNG to in-memory JPEG
require 'pdfcrowd'

begin
    # create the API client instance
    client = Pdfcrowd::ImageToImageClient.new("your_username", "your_apikey")

    # configure the conversion
    client.setOutputFormat("jpg")

    # create output file for conversion result
    output_file = open("logo.jpg", "wb")

    # run the conversion and store the result into an image variable
    image = client.convertRawData(open('/path/to/logo.png', 'rb').read())

    # write the image the into the output file
    output_file.write(image)

    # close the output file
    output_file.close()
rescue Pdfcrowd::Error => why
    # report the error
    STDERR.puts "Pdfcrowd Error: #{why}"

    # handle the exception here or rethrow and handle it at a higher level
    raise
end
Convert an in-memory PNG and write the resulting JPEG to an output stream
require 'pdfcrowd'

begin
    # create the API client instance
    client = Pdfcrowd::ImageToImageClient.new("your_username", "your_apikey")

    # configure the conversion
    client.setOutputFormat("jpg")

    # create output stream for conversion result
    output_stream = open("logo.jpg", "wb")

    # run the conversion and write the result into the output stream
    client.convertRawDataToStream(open('/path/to/logo.png', 'rb').read(), output_stream)

    # close the output stream
    output_stream.close()
rescue Pdfcrowd::Error => why
    # report the error
    STDERR.puts "Pdfcrowd Error: #{why}"

    # handle the exception here or rethrow and handle it at a higher level
    raise
end
Get info about the current conversion
require 'pdfcrowd'

begin
    # create the API client instance
    client = Pdfcrowd::ImageToImageClient.new("your_username", "your_apikey")

    # configure the conversion
    client.setOutputFormat("jpg")
    client.setDebugLog(true)

    # run the conversion and write the result to a file
    client.convertFileToFile("/path/to/logo.png", 'logo.jpg')
    
    # print URL to the debug log
    puts "Debug log url: #{client.getDebugLogUrl()}"
    
    # print the number of available conversion credits in your account
    puts "Remaining credit count: #{client.getRemainingCreditCount()}"
    
    # print the number of credits consumed by the conversion
    puts "Consumed credit count: #{client.getConsumedCreditCount()}"
    
    # print the unique ID of the conversion
    puts "Job id: #{client.getJobId()}"
    
    # print the size of the output in bytes
    puts "Output size: #{client.getOutputSize()}"
rescue Pdfcrowd::Error => why
    # report the error
    STDERR.puts "Pdfcrowd Error: #{why}"

    # handle the exception here or rethrow and handle it at a higher level
    raise
end

Tips & Tricks

API Reference - class ImageToImageClient

Conversion from one image format to another image format.

Constructor

def initialize(user_name, api_key)
Constructor for the Pdfcrowd API client.
Parameter Description Default
user_name
Your username at Pdfcrowd.
api_key
Your API key.

 

Conversion Input

def convertUrl(url)
Convert an image.
Parameter Description Default
url
The address of the image to convert.
The supported protocols are http:// and https://.
Returns
  • byte[] - Byte array containing the conversion output.
def convertUrlToStream(url, out_stream)
Convert an image and write the result to an output stream.
Parameter Description Default
url
The address of the image to convert.
The supported protocols are http:// and https://.
out_stream
The output stream that will contain the conversion output.
def convertUrlToFile(url, file_path)
Convert an image and write the result to a local file.
Parameter Description Default
url
The address of the image to convert.
The supported protocols are http:// and https://.
file_path
The output file path.
The string must not be empty.
def convertFile(file)
Convert a local file.
Parameter Description Default
file
The path to a local file to convert.
The file can be either a single file or an archive (.tar.gz, .tar.bz2, or .zip).
The file must exist and not be empty.
Returns
  • byte[] - Byte array containing the conversion output.
def convertFileToStream(file, out_stream)
Convert a local file and write the result to an output stream.
Parameter Description Default
file
The path to a local file to convert.
The file can be either a single file or an archive (.tar.gz, .tar.bz2, or .zip).
The file must exist and not be empty.
out_stream
The output stream that will contain the conversion output.
def convertFileToFile(file, file_path)
Convert a local file and write the result to a local file.
Parameter Description Default
file
The path to a local file to convert.
The file can be either a single file or an archive (.tar.gz, .tar.bz2, or .zip).
The file must exist and not be empty.
file_path
The output file path.
The string must not be empty.
def convertRawData(data)
Convert raw data.
Parameter Description Default
data
The raw content to be converted.
Returns
  • byte[] - Byte array with the output.
def convertRawDataToStream(data, out_stream)
Convert raw data and write the result to an output stream.
Parameter Description Default
data
The raw content to be converted.
out_stream
The output stream that will contain the conversion output.
def convertRawDataToFile(data, file_path)
Convert raw data to a file.
Parameter Description Default
data
The raw content to be converted.
file_path
The output file path.
The string must not be empty.

 

Conversion Format

def setOutputFormat(output_format)
The format of the output file.
Parameter Description Default
output_format
Allowed values:
  • png
  • jpg
  • gif
  • tiff
  • bmp
  • ico
  • ppm
  • pgm
  • pbm
  • pnm
  • psb
  • pct
  • ras
  • tga
  • sgi
  • sun
  • webp
png
Returns
  • ImageToImageClient - The converter object.

 

Image operations

Settings used for operations with images.

def setResize(resize)
Resize the image.
Parameter Description Default
resize
The resize percentage or new image dimensions.
100%
Returns
  • ImageToImageClient - The converter object.
Examples:
  • setResize("200%")
  • setResize("1024x768")
def setRotate(rotate)
Rotate the image.
Parameter Description Default
rotate
The rotation specified in degrees.
0
Returns
  • ImageToImageClient - The converter object.

 

Miscellaneous

def setDebugLog(debug_log)
Turn on the debug logging. Details about the conversion are stored in the debug log. The URL of the log can be obtained from the getDebugLogUrl method.
Parameter Description Default
debug_log
Set to true to enable the debug logging.
false
Returns
  • ImageToImageClient - The converter object.
def getDebugLogUrl()
Get the URL of the debug log for the last conversion.
Returns
  • string - The link to the debug log.
def getRemainingCreditCount()
Get the number of conversion credits available in your account.
The returned value can differ from the actual count if you run parallel conversions.
The special value 999999 is returned if the information is not available.
Returns
  • int - The number of credits.
def getConsumedCreditCount()
Get the number of credits consumed by the last conversion.
Returns
  • int - The number of credits.
def getJobId()
Get the job id.
Returns
  • string - The unique job identifier.
def getOutputSize()
Get the size of the output in bytes.
Returns
  • int - The count of bytes.
def setTag(tag)
Tag the conversion with a custom value. The tag is used in conversion statistics. A value longer than 32 characters is cut off.
Parameter Description Default
tag
A string with the custom tag.
Returns
  • ImageToImageClient - The converter object.

 

API Client Options

def setUseHttp(use_http)
Specifies if the client communicates over HTTP or HTTPS with Pdfcrowd API.
Parameter Description Default
use_http
Set to true to use HTTP.
false
Returns
  • ImageToImageClient - The converter object.
def setUserAgent(user_agent)
Set a custom user agent HTTP header. It can be usefull if you are behind some proxy or firewall.
Parameter Description Default
user_agent
The user agent string.
pdfcrowd_ruby_client/4.3.5 (http://pdfcrowd.com)
Returns
  • ImageToImageClient - The converter object.
def setProxy(host, port, user_name, password)
Specifies an HTTP proxy that the API client library will use to connect to the internet.
Parameter Description Default
host
The proxy hostname.
port
The proxy port.
user_name
The username.
password
The password.
Returns
  • ImageToImageClient - The converter object.
def setRetryCount(retry_count)
Specifies the number of retries when the 502 HTTP status code is received. The 502 status code indicates a temporary network issue. This feature can be disabled by setting to 0.
Parameter Description Default
retry_count
Number of retries wanted.
1
Returns
  • ImageToImageClient - The converter object.

 

Error Handling

begin 
    # call the API 
rescue Pdfcrowd::Error => why 
    # print error
    STDERR.puts "Pdfcrowd Error: #{why}"

    # print just error code
    STDERR.puts "Pdfcrowd Error Code: #{why.getCode()}"

    # print just error message
    STDERR.puts "Pdfcrowd Error Message: #{why.getMessage()}"

    # or handle the error by your way
end

Troubleshooting