I was searching for a nice image viewer for python for a long time and I’ve just tested napari viewer and I find it great! I really like the flexibility
However the following features are missing for me to use it:
Correctly manage float images > it is assumed that the contrast is between 0 and 1… My images are not in this range… Also pixel intensity displayed in the bottom left are changed to 1 for RGB images… It should display the real intensity values otherwise I cannot trust the values.
Correctly manage uint16 images > max value for the contrast slider is 2.91e+03… why? Also intensity resolution is highly reduced (I see flat colors) as if the image was converted to uint8
Set min and max contrast values manually instead of using a slider. I need to set the same contrast on two images to compare, not possible with sliders.
Would be nice to implement the mouse control for contrast (left-right drag) and intensity (up-down drag). Usually present in other viewers
Manage .JP2 (jpeg2000) file format
Display zoom factor. And implement magnet effect for 100% zoom factor > I need to see the image at exactly 100% sometimes (or a integer rescale factor such as 300%).
measure distances. Line tool does not display distances…
toggle between RGB and single band view. In general, RGB is not correctly managed.
We’re making good progress on having a nice global coordinate system, and will then think about scale bars, measurement tools. That might be separate functionality from the Line in Shapes, but we’ll see. For now if you wanted to get the length of each line you’d have to do it programmatically from the layer data.
Displaying zoom is a good idea, we don’t do that now, but can do that maybe when we improve our camera model https://github.com/napari/napari/pull/854. You can do cmd+R to reset the zoom to it’s original position, we don’t have something to set at 1 data pixel/ 1 screen pixel, but could add that.
We support the ability to have custom mouse functions, right now we just added ctrl scroll to move the dimension sliders, but could think about this too and what the best short cuts are.
By default we’re setting the min/ max to the values to the image data, but these can be changed with the contrast_limits_range parameter or using the pop-out slider i mentioned above.
I’ll have to look into this more, we shouldn’t be making assumptions there on the float, and anything should be settable with contrast_limits_range and contrast_limits, but something strange might be happening for RBG data.