PDF Geometry: How Permanent Rotation Works in Document Metadata
Learn why standard saving fails and how Metadata Injection ensures your documents stay upright forever.
Most users are frustrated when they rotate a PDF in their browser, only for it to revert to the original orientation after saving. This happens because they are changing the View State (a temporary local preference), not the Document Property.
The /Rotate Flag vs. Content Transformation
In the PDF specification (ISO 32000), each page object contains a dictionary. Within this dictionary lies the /Rotate entry. This entry only accepts values in multiples of 90 (0, 90, 180, 270).
Instead of re-rendering all the text and images—which often leads to quality loss and file bloat—our Sigma-Rotate engine performs an In-Place Dictionary Update. We target the binary stream and rewrite the rotation key directly at the object level.
Technical Advantage
Because we modify metadata rather than re-encoding the image stream, the process is lossless. Your text remains searchable, and your high-res images maintain their original DPI (Dots Per Inch).
Coordinate System Mapping
When a page is rotated, the MediaBox (the physical page boundaries) remains constant in the file's data. However, the internal coordinate system is mathematically transformed. For example, a 90-degree clockwise rotation swaps the X and Y axis logic for the renderer.
Fix Your Document Orientation
Perform permanent, surgical rotation with our visual engine.
Launch Sigma-RotateSecurity and Privacy
PDFTeq's rotation engine operates using Client-Side Execution. By leveraging WebAssembly and the pdf-lib library, the transformation happens inside your browser's sandbox. Your confidential documents never travel to our servers, fulfilling strict data sovereignty requirements.