Re: Re: Acquiring Dental RVG on Linux
On Wed, Jan 06, 2021 at 05:13:58PM +0530, Sonali Warunjikar wrote:
> I think distance calibration is over. Now over to other image parameters.
Some observations about depth (bits per pixel):
- The proprietary software is producing images with only 8 bit depth,
throwing away half of the data (data is 12 bit + 4 filler bits) gathered
from the sensor.
- Most monitors available commercially do not support a depth > 8 anyway.
Special purpose monitors with higher depth aren't easy to find (might be
costly if found). Practitioners aren't seen using them anyway.
- "Even for high brightness and high contrast medical displays with
luminance range between 0.5 and 2000 cd/m2, the human observer can
perceive no more than around 900 shades of gray" 
This means at the most 10 bits can be relevant for human consumption.
It's a different matter if the images are to be analyzed by software.
- "The radiologists did not attest the higher grayscale resolution a
better image quality, they regarded the 8-bit technology to show a
better sharpness and contrast, although this had no impact on the
detectability of details." 
It could be that the extra grey shades result in showing more fragmented
view which the practitioners aren't accustomed to after years of
practice with 8 bit depth. (My speculation.) And it's not going to be
easy to make them adapt a higher depth.
So in summary, I am just going to follow the suit and throw away the first
byte (it's little endian) and resort to 8 bit images in pyrvg software. It
will also open up the choices of image handling software as many of even
widely used ones do not support depths > 8.