Mimikri Frequently Asked Questions
How does Mimikri work?
Mimikri compares uncorrected and corrected images made in one resolution (standard definition) and applies the
result to an image in another resolution (high definition).
Mimikri does not have to know how actually the color correction was made. It makes a statistical analysis of
the color spaces in both the uncorrected and corrected image and creates color vectors which estimate the offset of
the color correction.
Mimikri can work in a color mode, which analyzes the whole image, which will allow for primary and secondary color
correction. It can also work in a space mode, which analyzes also the location of the pixels and therefore can process
spot color correction.
Mimikri works both in RGB space as in Component space (Y Cb Cr), and the results are comparable.
The user will only have to set the mode, the rest of the process is automatic.
How can I use Mimikri?
Mimikri will be available in various implementations:
- As a service of digital film labs.
This will be a preferrable workflow, because the digital film lab
already has the HDCAM deck and downconverted the tapes for you, and on the other side, it will do the film out.
- As a plugin for After Effects
- As a standalone application for OS-X
How do I prepare my film for Mimikri?
The quality of the image should be preserved at it's best.
- Downconvert from HDCAM as 16:9 (no letterbox), use preset values (no sharpening), and with no BITC (burned in timecode).
- Digitize to your offline color correction system as uncompressed as possible.
- Do your color correction.
- Export both the uncorrected and the corrected sequence as Quicktime with source compression (to ensure registration).
Note: If you work in NTSC, you have to export the sequence at 24 fps, without pulldown.
- Digitize the HDCAM to Quicktime. Ensure that black and white levels of both SD and HD are the same.
How fast is Mimikri?
This will depend on the processor, the access time to the harddisk and on the platform. The filter itself has a complexity which is comparable with a
good quality blur or with intra-frame noise reduction.
What is the meaning of the Color and the Space mode?
In Mimikri, you have the choice to use two methods to analyze the color correction.
- The Color mode creates the color offset model independent of space. This is the faster mode, but it will only do primary and secondary color correction. It will get confused by spot color correction.
- The Space mode create the color offset model using the neighbourhood of the pixels. This mode can do spot color correction and sometimes does better extreme secondary correction. However, this mode is slower and needs accurate pin registration between HD and SD.
Normally, spot color correction is only applied to a fraction of the footage. If you have information about the color correction, you will use Color mode in most of the cases and separate the footage which needs Space mode. If you are not sure and have the time, use first Color mode and redo the footage which does not work in Space mode. However, you can also decide from the beginning to do all footage in Space mode.
A special case is when you need to lengthen a shot which has been color corrected. In this case, you can only use Color mode.
What are the limitations of Mimikri?
- Mimikri cannot be better than the original color correction. The color grader has to make more attention to the work, because
flaws which maybe not perceived in standard definition will be very visible in high definition.
- Mimikri needs proper registration of the standard definition images and the image should be compressed as less as possible,
as errors in both will affect the statistical analysis.
- Mimikri needs the standard and high definition images to be encoded in the same color space and with the same black and white levels (eg 0-255 or 16-235).
- Mimikri cannot take account of factors which are resolution dependent such as sharpness and noise. It will not conform sharpness enhancing nor noise reduction sometimes used in color correction. Also, color graders may take slightly other decisions on an image with SD resolution than on
an image in HD.
- Mimikri cannot do compositing like chroma key.
I have a friend with a Final Cut Pro on his Powerbook and he will colorgrade my first HD short film.
Will I be able to use Mimikri to upgrade it to HD?
As I said before, Mimikri cannot be better than the original color correction. You need a experienced color grader to
successfully color correct your film, and he must also have the tools to properly judge the image (reference monitor, waveform).
Can I restore a color correction with Mimikri?
We actually used Mimikri for that on a feature film. They corrected the film in 3 days on a DaVinci. Later, they decided to recut the first reel, because it was too much long. However, when you cut, you always have to add some frames here and there. With Mimikri, we could apply the color correction from the shot to the new frames.
What does the word Mimikri mean?
Mimikri (actually: Mimikry) is a technique of insects to mime an aspect of another animal which is dangerous
and therefore avoided by birds. We do not have the budget of George Lucas here in Europe, but still want to make
good looking movies.