Saving a printable form and recognition pattern

After the template has been successfully generated, you can save it to disk in the preferred format.

The saved results consist of several files:

• Printable form as an image or PDF document.
• A recognition pattern used by Aspose.OMR recognition engine, in a special .OMR format. This file is required for mapping optical marks to form elements and is necessary for recognizing filled forms!

Saving form to a file

The printable form can be saved in one or more images (one image per page) or in one PDF document. Regardless of the chosen format, the recognition pattern file is always saved to the save folder.

Saving form as an image

Call Save method of of the GenerationResult object returned by Generate method. The method takes the following arguments:

• Target directory name, either absolute or relative to your application’s working directory. Provide an empty string to save files into the working directory.
• File name (without extension) for printable form pages and the recognition pattern. Each page is always saved as a separate file. If multiple pages are generated, the suffix “Page{NUMBER}” will be added to each file; for example, “OMR-FormPage1.png”.

Printable pages are saved as PNG images. Their dimensions match the provided paper size and orientation.

Source code

Aspose.OMR.Api.OmrEngine omrEngine = new Aspose.OMR.Api.OmrEngine();
Aspose.OMR.Generation.GenerationResult generationResult = omrEngine.Generate("source.txt");
if(generationResult.ErrorCode != 0)
{
	Console.WriteLine(generationResult.ErrorMessage);
	return generationResult.ErrorCode;
}
generationResult.Save("", "OMR-Form");

Saved files

• OMR-Form.png
• OMR-Form.omr

Saving form as a PDF document

The method described below is used for saving a form as an image-only (printable) PDF. To convert bubbles ant write-ins to interactive elements that can be filled electronically, use Aspose.OMR.Generation.GenerationResult.SaveAsInteractivePdf() method.

This is the recommended method for saving multi-page forms.

Call SaveAsPdf method of of the GenerationResult object returned by Generate method. The method takes the following arguments:

• Target directory name, either absolute or relative to your application’s working directory. Provide an empty string to save files into the working directory.
• File name (without extension) for a printable form and the recognition pattern. All pages are saved to a single PDF document.

Source code

Aspose.OMR.Api.OmrEngine omrEngine = new Aspose.OMR.Api.OmrEngine();
Aspose.OMR.Generation.GenerationResult generationResult = omrEngine.Generate("source.txt");
if(generationResult.ErrorCode != 0)
{
	Console.WriteLine(generationResult.ErrorMessage);
	return generationResult.ErrorCode;
}
generationResult.SaveAsPdf("", "OMR-Form");

Saved files

• OMR-Form.pdf
• OMR-Form.omr

Saving form as an interactive PDF

The method described below is used for saving a form as a PDF document with interactive elements, such as fields and checkboxes, enabling users to fill it electronically on a computer or smartphone. To get a PDF document that can be printed and filled by hand, use Aspose.OMR.Generation.GenerationResult.SaveAsPdf() method.

Saving a form as an interactive PDF may take longer if the page contains many interactive elements, such as bubbles and write-in fields.If you encounter significant performance issues, consider splitting the source into smaller forms.

The following markup elements are supported in interactive PDFs:

• Choice box: a question with a fixed number of answers. Each bubble is converted to an interactive checkbox.
• Vertical choice box: a vertical block with answers and an optional write-in element. Each bubble is converted to an interactive checkbox; write-in element is converted to a text input field.
• Checkbox: a list of answers with blank boxes, which can contain any marks - from marker filling to light pencil checks. Each checkbox is converted to an interactive checkbox.
• Grid: a block consisting of numbered bubbles which are recognized as a whole, resulting in all marked bubbles forming a single answer. Each bubble is converted to an interactive checkbox.
• Answer sheet: a numbered matrix of bubbles representing answers to a list of questions. Each bubble is converted to an interactive checkbox.
• Score group: a group of questions with multiple evaluation criteria. The marked criteria for each question are summarized upon recognition and the resulting value is used as an answer for the question. Each bubble is converted to an interactive checkbox.
• Write-in: a blank field in which the respondent can hand write some text. This element is converted to a text input field.
• Barcode: a barcode or QR code based on the provided string. It is represented as a non-interactive image.

Call SaveAsInteractivePdf method of of the GenerationResult object returned by Generate method. The method takes the following arguments:

• Target directory name, either absolute or relative to your application’s working directory. Provide an empty string to save files into the working directory.
• File name (without extension) for a printable form and the recognition pattern. All pages are saved to a single PDF document.

Source code

Aspose.OMR.Api.OmrEngine omrEngine = new Aspose.OMR.Api.OmrEngine();
Aspose.OMR.Generation.GenerationResult generationResult = omrEngine.Generate("source.txt");
if(generationResult.ErrorCode != 0)
{
	Console.WriteLine(generationResult.ErrorMessage);
	return generationResult.ErrorCode;
}
generationResult.SaveAsInteractivePdf("", "OMR-Form");

Saved files

• OMR-Form.pdf
• OMR-Form.omr

Generating form to a memory stream

If you do not have direct access to storage (for example, when building web applications), you can generate the form into memory.

This approach requires that the recognition pattern be generated separately.

To enable in-memory form generation, convert the object returned by Generate method to MemoryGenerationResult object:

Aspose.OMR.Api.OmrEngine omrEngine = new Aspose.OMR.Api.OmrEngine();
Aspose.OMR.Generation.GenerationResult generationResult = omrEngine.Generate("source.txt");
if(generationResult.ErrorCode != 0)
{
	Console.WriteLine(generationResult.ErrorMessage);
	return generationResult.ErrorCode;
}
Aspose.OMR.Generation.MemoryGenerationResult memoryGenerationResult = new Aspose.OMR.Generation.MemoryGenerationResult(generationResult);

Getting form pages as images

Call GetImages method of the MemoryGenerationResult object. All pages of the OMR form are returned as a collection of MemoryStream objects containing bitmap images of form pages.

IEnumerable<MemoryStream> pages = memoryGenerationResult.GetImages();
foreach(var page in pages)
{
	byte[] pageImageBytes = page.ToArray();
}

Getting form as PDF document

Call GetPDF method of the MemoryGenerationResult object. All pages of the OMR form are returned as a MemoryStream object containing a PDF document.

MemoryStream form = memoryGenerationResult.GetPDF();
byte[] formBytes = form.ToArray();

Getting recognition pattern

Call GetOmr method of the MemoryGenerationResult object. The recognition pattern is returned as a MemoryStream object.

MemoryStream omr = memoryGenerationResult.GetOmr();
byte[] recognitionPattern = omr.ToArray();

Iterating through pages

GenerationResult object returned by Generate method also contains a collection of all generated printable pages (as System.Drawing.Bitmap objects). You can manually iterate through this list and save the pages in different formats if necessary.

Example

Aspose.OMR.Api.OmrEngine omrEngine = new Aspose.OMR.Api.OmrEngine();
Aspose.OMR.Generation.GenerationResult generationResult = omrEngine.Generate("source.txt");
if(generationResult.ErrorCode != 0)
{
	Console.WriteLine(generationResult.ErrorMessage);
	return generationResult.ErrorCode;
}
int i = 1;
foreach(System.Drawing.Bitmap bitmap in generationResult.MultipageTemplateImages)
{
	bitmap.Save($"page-{i++}.bmp");
}