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Advanced PNG Conversion Options - C#

PDF to PNG sample in C# demonstrating ‘Advanced PNG Conversion Options’

using System;
using System.IO;
using System.Net;
using Newtonsoft.Json.Linq;
using System.Threading;
using System.Collections.Generic;
using Newtonsoft.Json;

// Cloud API asynchronous "PDF To PNG" job example.
// Allows to avoid timeout errors when processing huge or scanned PDF documents.

The following options are available through profiles:
(JSON can be single/double-quoted and contain comments.)
    "profiles": [
            "profile1": {
                "TextSmoothingMode": "HighQuality", // Valid values: "HighSpeed", "HighQuality"
                "VectorSmoothingMode": "HighQuality", // Valid values: "HighSpeed", "HighQuality"
                "ImageInterpolationMode": "HighQuality", // Valid values: "HighSpeed", "HighQuality"
                "RenderTextObjects": true, // Valid values: true, false
                "RenderVectorObjects": true, // Valid values: true, false
                "RenderImageObjects": true, // Valid values: true, false
                "RenderCurveVectorObjects": true, // Valid values: true, false
                "JPEGQuality": 85, // from 0 (lowest) to 100 (highest)
                "TIFFCompression": "LZW", // Valid values: "None", "LZW", "CCITT3", "CCITT4", "RLE"
                "RotateFlipType": "RotateNoneFlipNone", // RotateFlipType enum values from here:
                "ImageBitsPerPixel": "BPP24", // Valid values: "BPP1", "BPP8", "BPP24", "BPP32"
                "OneBitConversionAlgorithm": "OtsuThreshold", // Valid values: "OtsuThreshold", "BayerOrderedDithering"
                "FontHintingMode": "Default", // Valid values: "Default", "Stronger"
                "NightMode": false // Valid values: true, false

namespace ByteScoutWebApiExample
    class Program
        // The authentication key (API Key).
        // Get your own by registering at
        const String API_KEY = "***********************************";
        // Source PDF file
        const string SourceFile = @".\sample.pdf";

        // Comma-separated list of page indices (or ranges) to process. Leave empty for all pages. Example: '0,2-5,7-'.
        const string Pages = "";

        // PDF document password. Leave empty for unprotected documents.
        const string Password = "";

        // (!) Make asynchronous job
        const bool Async = true;

        // Advanced options
        const string Profiles = "{ 'profiles': [ { 'profile1': { 'ImageBitsPerPixel': 'BPP1' } } ] }";

        static void Main(string[] args)
            // Create standard .NET web client instance
            WebClient webClient = new WebClient();

            // Set API Key
            webClient.Headers.Add("x-api-key", API_KEY);

            // * If you already have a direct file URL, skip to the step 3.

            // Prepare URL for `Get Presigned URL` API call
            string query = Uri.EscapeUriString(string.Format(

                // Execute request
                string response = webClient.DownloadString(query);

                // Parse JSON response
                JObject json = JObject.Parse(response);

                if (json["error"].ToObject<bool>() == false)
                    // Get URL to use for the file upload
                    string uploadUrl = json["presignedUrl"].ToString();
                    // Get URL of uploaded file to use with later API calls
                    string uploadedFileUrl = json["url"].ToString();

                    // 2. UPLOAD THE FILE TO CLOUD.

                    webClient.Headers.Add("content-type", "application/octet-stream");
                    webClient.UploadFile(uploadUrl, "PUT", SourceFile); // You can use UploadData() instead if your file is byte[] or Stream

                    // 3. CONVERT UPLOADED PDF FILE TO PNG

                    // URL for `PDF To PNG` API call
                    var url = "";

                    // Prepare requests params as JSON
                    Dictionary<string, object> parameters = new Dictionary<string, object>();
                    parameters.Add("password", Password);
                    parameters.Add("pages", Pages);
                    parameters.Add("url", uploadedFileUrl);
                    parameters.Add("async", Async);
                    parameters.Add("profiles", Profiles);

                    // Convert dictionary of params to JSON
                    string jsonPayload = JsonConvert.SerializeObject(parameters);

                    // Execute POST request with JSON payload
                    response = webClient.UploadString(url, jsonPayload);

                    // Parse JSON response
                    json = JObject.Parse(response);

                    if (json["error"].ToObject<bool>() == false)
                        // Asynchronous job ID
                        string jobId = json["jobId"].ToString();
                        // URL of generated JSON file available after the job completion; it will contain URLs of result PNG files.
                        string resultJsonFileUrl = json["url"].ToString();

                        // Check the job status in a loop. 
                        // If you don't want to pause the main thread you can rework the code 
                        // to use a separate thread for the status checking and completion.
                            string status = CheckJobStatus(jobId); // Possible statuses: "working", "failed", "aborted", "success".

                            // Display timestamp and status (for demo purposes)
                            Console.WriteLine(DateTime.Now.ToLongTimeString() + ": " + status);

                            if (status == "success")
                                // Download JSON file as string
                                string jsonFileString = webClient.DownloadString(resultJsonFileUrl);

                                JArray resultFilesUrls = JArray.Parse(jsonFileString);

                                // Download generated PNG files
                                int page = 1;
                                foreach (JToken token in resultFilesUrls)
                                    string resultFileUrl = token.ToString();
                                    string localFileName = String.Format(@".\page{0}.png", page);

                                    webClient.DownloadFile(resultFileUrl, localFileName);

                                    Console.WriteLine("Downloaded \"{0}\".", localFileName);

                            else if (status == "working")
                                // Pause for a few seconds
                        while (true);
            catch (WebException e)


            Console.WriteLine("Press any key...");

        static string CheckJobStatus(string jobId)
            using (WebClient webClient = new WebClient())
                // Set API Key
                webClient.Headers.Add("x-api-key", API_KEY);

                string url = "" + jobId;

                string response = webClient.DownloadString(url);
                JObject json = JObject.Parse(response);

                return Convert.ToString(json["status"]);
} Web API: the Web API with a set of tools for documents manipulation, data conversion, data extraction, splitting and merging of documents. Includes image recognition, built-in OCR, barcode generation and barcode decoders to decode bar codes from scans, pictures and pdf.

Get your API key here!

Download Source Code (.zip)

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