Alchemist XF Discover the Benefits

Stunning pictures

Alchemist XF builds on our Emmy® award winning technology to bring you breath taking motion compensated image quality. Our algorithms benefit from more than two decades of research and experience into the exacting demands of format and frame rate media transformation.

We understand the importance of being able to guarantee your deliverables, meet your client’s requirements and avoid having work rejected on the grounds of quality control. Being able to turn work around fast and minimize manual intervention enables you to keep your costs down.

Alchemist XF has been carefully optimized to offer the very best image quality however complex the source. Our solution also prevents the need for multiple transfers of the same assets by removing unnecessary conversion parameters.

Stunning pictures - first time, every time.

Optimized to offer the very best image quality however complex the source.

Our finest de-interlacer is now available.

Alchemist XF offers our latest intelligent adaptive de-interlacing to provide the sharpest pictures ever. Using a robust motion detector, our technology can intelligently soft switch the optimum de-interlacing mode on a pixel by pixel basis to ensure each pixel maintains the maximum possible resolution.

Each de-interlacing mode has been carefully engineered to focus on a particular property of real images. These include static, vertical temporal and  diagonal apertures of varying gradients. The use of soft switching  avoids switching artefacts which can otherwise look more objectionable than the original interlace artefacts.

Multi-dimensional motion adaptive de-interlacing

Motion estimation has just got better!

A motion estimator usually works on a local basis in the picture and measures not only the existence of motion but also its speed and direction. For frame rate conversion the output of the motion estimator provide the required motion vectors for picture building.

The motion estimator used in Alchemist XF has three major advances over our existing technology.

Improvement 1: Multi-scale candidate vector generation.

Our existing motion estimation technology makes use of phase correlation to analyse a scene and to generate candidate motion vectors for subsequent assignment to individual pixels.  The phase correlation is based on large blocks, whose size is a trade-off between motion range and ability to handle small or detailed objects.  We have seen that both are required, so Mensa uses multiple block sizes in parallel to generate candidate motion vectors of both kinds.

Improvement 2: Gradient-based refinement.

Another challenge of the existing technology is the inability to handle smooth variations of motion within objects, such as zooms, rotations and perspective in a receding landscape. Alchemist XF solves this problem by allowing the candidate motion vectors to vary slowly from pixel to pixel, using gradient based techniques to refine the vectors from initial constant values. One of the drawbacks of such gradient-based vector refinement is that it fails at motion boundaries.  We overcome this problem by using overlapping blocks, with a weighting system to encourage refinement to work hardest in areas where the vector field is already performing well.  This has the effect that one overlapping block covering a motion boundary will refine a vector field suitable for one side of the boundary but not necessarily the other, while another overlapping block will refine a field for the other side.

Improvement 3: Vector assignment.

The final step in motion estimation is to assign a motion vector to every pixel from the set of refined candidates.  The classic way to assign motion vectors is to calculate an error surface for each candidate, usually a displaced frame difference (DFD).  This surface is then filtered spatially so that the error generated by a candidate for a pixel contains information about the neighbourhood of the pixel.  It is difficult to choose the right size for this filter: too small, and the vector field is noisy; too large, and small objects can be missed and behaviour at motion boundaries is poor.  For Mensa, we have developed a nonlinear DFD filter based on splitting the neighbourhood into octants, as shown in Figure 2, and applying a minimax approach that allows a motion boundary to pass through the neighbourhood while retaining the stability of a large filter.

All new smooth picture building.

The picture builder takes the input pictures and associated motion vector fields and uses them to build an output picture at a desired time instant.  Because motion vectors are associated with input pixels and not output pixels, a projection operation is required in which input pixels are written into the output picture at locations determined by the motion vectors and the desired temporal phase.  Such projection requires mechanisms for handling occlusions, multiple “hits” from different input pixels, “holes” where an output location is not written, and sub-pixel interpolation.  It is at this stage that any problems resulting from inaccurate motion vectors, transparency, very complex motion and other transformations in the picture, may appear as annoying artefacts. These artefacts often manifest as object fractures. The new smooth picture building techniques eliminates the presence of such fractures.

New Adaptive Cadence Technology.

Introducing Adaptive Cadence Technology: the ultimate tool for handling film originated and mixed cadence media.

Our intelligent cadence detection dynamically adapts the conversion aperture to deliver beautifully sharp and fluid moving pictures.

Safeguard your business and deliver content in the exact format your clients specify it without the fear of costly rejections from customers or video-on-demand providers.

What is cadence?

In the broadcast world, cadence is a manipulation of source content, to achieve a frame rate change, by a process of repetition of source fields/frames, in a continuous sequence.

Different cadences can be introduced for creative effect, and many electronic editing processes can even break what was a continuous cadence.


Mixed cadence presents many challenges to the optimum standards conversion process.

Failure to detect the changes in cadence could result in loss of vertical resolution and introduce undesirable frame drops and repeats resulting in an irregular motion portrayal.

Alchemist XF uses new Adaptive Cadence Technology to address all of these issues. Saving you time and effort, the software revives troublesome files into a guaranteed format for modern file-based workflow and allows you to deliver content with confidence. 

Already have an SDI tool?

Alchemist XF is the next generation of Alchemist technology, specifically designed for the file-based domain. 

Alchemist XF is the next generation of Alchemist technology, specifically designed for the file-based domain. This scalable software solution offers you the ability to improve your efficiency and maximize your hardware resources.

Not only that but it improves on the SAM proprietary technology to deliver better conversion quality than any previous generation of Alchemist.

Existing Alchemist customer?

Here is how Alchemist XF compares to Alchemist HD.


Alchemist HD (hardware)

Alchemist XF (software)

New improved advanced motion adaptive de-interlacing     
New state of the art motion compensated low frame rate conversion     
World class motion compensated high frame rate conversion    
Up, down, cross and frame rate conversion     
Unrivalled RGB Legalizer      
Exceptional image rescaling      
Support for 2K      
Support for 4K      
Software on commodity IT      
Unattended 24/7 workflow      
Support for compressed broadcast files      
Audio Routing      
Captions (608/708)      
FilmTools (2:3 removal, insertion, mixed content support)      
Off speed conversion      Q3 2015*

* All new features are available to existing customers as part of their maintenance package. 

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