Summarizing the Text Content of PDF Documents using Text Analytics with Azure AI services

Updated over 6 months ago

Environment

Version	Product	Author
Q1 2025	RadPdfProcessing	Desislava Yordanova

Description

Learn how to summarize the text content of a PDF document using Text Analytics with Azure AI services.

Solution

Follow the steps:

1. Before going further, you can find listed below the required assemblies/NuGet packages that should be added to your project:

• Azure.AI.TextAnalytics
• Telerik.Documents.Fixed
• Telerik.Documents.Core
• Telerik.Zip

2. It is necessary to generate your Azure AI key and endpoint: Get your credentials from your Azure AI services resource

3. Extract the text content from a PDF document.

4. Use the custom implementation to summarize the text content extracted in step 3:

csharp

        static void Main(string[] args)
        {
            Telerik.Windows.Documents.Fixed.FormatProviders.Pdf.PdfFormatProvider pdf_provider = new PdfFormatProvider();
            Telerik.Windows.Documents.Fixed.FormatProviders.Text.TextFormatProvider text_provider = new TextFormatProvider();
            Telerik.Windows.Documents.Fixed.Model.RadFixedDocument document = pdf_provider.Import(File.ReadAllBytes("PdfDocument.pdf"), TimeSpan.FromSeconds(10));
            string documentTextContent = text_provider.Export(document);

            AzureTextSummarizationProvider summarizationProvider = new AzureTextSummarizationProvider(azure_key, azure_endpoint);
            string summary = summarizationProvider.SummarizeText(documentTextContent).Result;

            Console.WriteLine(summary);
        }

        public class AzureTextSummarizationProvider 
        {
            private string languageKey;
            private string languageEndpoint;

            public AzureTextSummarizationProvider(string azure_key, string azure_endpoint)
            {
                this.languageKey = azure_key;
                this.languageEndpoint = azure_endpoint;
            }

            public async Task<string> SummarizeText(string text)
            {
                Azure.AzureKeyCredential credentials = new Azure.AzureKeyCredential(languageKey);
                Uri endpoint = new Uri(languageEndpoint);

                Azure.AI.TextAnalytics.TextAnalyticsClient client = new Azure.AI.TextAnalytics.TextAnalyticsClient(endpoint, credentials);

                // Prepare analyze operation input. You can add multiple documents to this list and perform the same
                // operation to all of them.
                List<string> batchInput = new List<string>
            {
                text
            };

                Azure.AI.TextAnalytics.TextAnalyticsActions actions = new Azure.AI.TextAnalytics.TextAnalyticsActions()
                {
                    ExtractiveSummarizeActions = [new Azure.AI.TextAnalytics.ExtractiveSummarizeAction()]
                };

                // Start analysis process.
                Azure.AI.TextAnalytics.AnalyzeActionsOperation operation = await client.StartAnalyzeActionsAsync(batchInput, actions);
                await operation.WaitForCompletionAsync();

                System.Text.StringBuilder stringBuilder = new System.Text.StringBuilder();
                // View operation status.
                stringBuilder.AppendLine($"AnalyzeActions operation has completed");
                stringBuilder.AppendLine();

                stringBuilder.AppendLine($"Created On   : {operation.CreatedOn}");
                stringBuilder.AppendLine($"Expires On   : {operation.ExpiresOn}");
                stringBuilder.AppendLine($"Id           : {operation.Id}");
                stringBuilder.AppendLine($"Status       : {operation.Status}");

                stringBuilder.AppendLine();
                // View operation results.
                await foreach (Azure.AI.TextAnalytics.AnalyzeActionsResult documentsInPage in operation.Value)
                {
                    IReadOnlyCollection<Azure.AI.TextAnalytics.ExtractiveSummarizeActionResult> summaryResults = documentsInPage.ExtractiveSummarizeResults;

                    foreach (Azure.AI.TextAnalytics.ExtractiveSummarizeActionResult summaryActionResults in summaryResults)
                    {
                        if (summaryActionResults.HasError)
                        {
                            stringBuilder.AppendLine($"  Error!");
                            stringBuilder.AppendLine($"  Action error code: {summaryActionResults.Error.ErrorCode}.");
                            stringBuilder.AppendLine($"  Message: {summaryActionResults.Error.Message}");
                            continue;
                        }

                        foreach (Azure.AI.TextAnalytics.ExtractiveSummarizeResult documentResults in summaryActionResults.DocumentsResults)
                        {
                            if (documentResults.HasError)
                            {
                                stringBuilder.AppendLine($"  Error!");
                                stringBuilder.AppendLine($"  Document error code: {documentResults.Error.ErrorCode}.");
                                stringBuilder.AppendLine($"  Message: {documentResults.Error.Message}");
                                continue;
                            }

                            stringBuilder.AppendLine($"  Extracted the following {documentResults.Sentences.Count} sentence(s):");
                            stringBuilder.AppendLine();

                            foreach (Azure.AI.TextAnalytics.ExtractiveSummarySentence sentence in documentResults.Sentences)
                            {
                                stringBuilder.Append($"{sentence.Text} ");
                            }
                        }
                    }
                }

                string result = stringBuilder.ToString();

                return result;
            }
        }             

See Also

• Extracting Text from PDF Documents
• OcrFormatProvider
• TextFormatProvider