Fine-Tune HTML, SVG, MHTML, and EPUB Rendering in Python

Use the Converter class for common conversions with save options. Use document.render_to() to send one loaded document directly to an output device, or use a source-specific renderer when the application needs direct control over the rendering pipeline.

Aspose.HTML for Python via .NET provides a high-level conversion API and a lower-level rendering API. Both can produce PDF, XPS, DOCX, and raster images, but they expose different levels of control.

Converter API vs. Rendering API

Approach	Use it when
Converter methods	You need a concise conversion workflow with format-specific save options. This is the usual choice for HTML, SVG, MHTML, EPUB, and Markdown conversion.
document.render_to(device)	You already have a loaded document and want to render it directly to a configured output device.
Renderer.render()	You need to work explicitly with HtmlRenderer, SvgRenderer, MhtmlRenderer, or EpubRenderer and a target device.

Save options belong to the high-level Converter workflow. Rendering options are passed to rendering devices in the lower-level workflow. Choose one approach for a conversion rather than combining save options and rendering options in the same call.

How the Rendering Pipeline Works

The rendering API separates the source type, rendering process, output format, and output settings:

Component	Purpose	Examples
Source	Supplies the document or source stream to render	HTMLDocument, SVGDocument, MHTML stream, EPUB stream
Renderer	Processes the corresponding source type	HtmlRenderer, SvgRenderer, MhtmlRenderer, EpubRenderer
Device	Defines the output format and destination	PdfDevice, XpsDevice, DocDevice, ImageDevice
Rendering options	Configure layout and format-specific output behavior	PdfRenderingOptions, XpsRenderingOptions, DocRenderingOptions, ImageRenderingOptions

The device determines the target format; it does not determine the source type. For example, PdfDevice can receive drawing operations produced from HTML, SVG, MHTML, or EPUB workflows and write them as PDF.

Render HTML to PDF with PdfDevice

The following example uses the lower-level rendering API with default PDF rendering options. It loads a webpage into an HTMLDocument, creates a PdfDevice, and sends the document to that device with render_to().

To render a loaded document to an output device:

1. Load or create the source document.
2. Create the device for the required output format and specify the destination.
3. Call render_to() on the document and pass the device.

import aspose.html as ah
import aspose.html.rendering.pdf as rp

with ah.HTMLDocument("https://docs.aspose.com/html/files/document.html") as document:
    device = rp.PdfDevice("document.pdf")
    document.render_to(device)

The result is document.pdf created with the default settings of PdfDevice. To customize page layout, PDF security, image settings, or DOCX output, create the matching rendering-options object and pass it to the corresponding device.

Choose a Fine-Tuning Guide

• Rendering Devices – choose PdfDevice, XpsDevice, DocDevice, or ImageDevice for the required output format.
• Rendering Options – configure page layout and format-specific PDF, image, XPS, or DOCX settings.
• Renderers – work with HtmlRenderer, SvgRenderer, MhtmlRenderer, and EpubRenderer for different source types.

When to Use Fine-Tuning APIs

Use the rendering API when the application needs to:

• render an already loaded document directly to an output device;
• select a device independently of the source-document type;
• configure device-specific rendering options;
• work explicitly with a source-specific renderer.

For ordinary file, string, stream, or URL conversion, start with the appropriate Converter guide and move to the rendering API only when the lower-level workflow provides a practical advantage.

Related Conversion Guides

• HTML Converter – convert HTML to PDF, DOCX, images, MHTML, and Markdown with the high-level API.
• SVG Converter – convert SVG to PDF and raster image formats.
• MHTML Converter – convert MHTML web archives to document and image formats.
• EPUB Converter – convert EPUB publications to PDF, DOCX, and images.
• Markdown Converter – convert Markdown to HTML, PDF, DOCX, and images.

Other Platforms

• Fine-Tuning Converters in C#
• Fine-Tuning Converters in Java

Try Online Conversion Tools

Use the free online HTML applications for quick manual conversions. Use the Aspose.HTML for Python via .NET rendering API when output settings must be controlled in application code.