Add support for 32 bit PNG images on variable explorer

[colt18]

Issue Report Checklist

• [ ] Searched the issues page for similar reports
• [ ] Read the relevant sections of the Spyder Troubleshooting Guide and followed its advice
• [ ] Reproduced the issue after updating with conda update spyder (or pip, if not using Anaconda)
• [ ] Could not reproduce inside jupyter qtconsole (if console-related)
• [ ] Tried basic troubleshooting (if a bug/error)
  • [ ] Restarted Spyder
  • [ ] Reset preferences with spyder --reset
  • [ ] Reinstalled the latest version of Anaconda
  • [ ] Tried the other applicable steps from the Troubleshooting Guide
• [ ] Completed the Problem Description, Steps to Reproduce and Version sections below

Problem Description

32 bit PNG files (4 channels, RGB and alpha ) read with cv2 are not showing up on variable explorer. They do get imported and actually exist, like they can be accessed with typing variable name but can't be seen on var exp. However reading 24 bit PNG (RGB only) runs smooth.

What steps reproduce the problem?

1. Import a 32 bit PNG file with cv2.import(filename)
2. variable name not showing up on variable explorer

What is the expected output? What do you see instead?

Variable name should be visible on variable explorer

Paste Traceback/Error Below (if applicable)

PASTE TRACEBACK HERE

Versions

• Spyder version: 4.1.3
• Python version: 3.7
• Qt version: 4.7.4
• PyQt version: 1.9.0
• Operating System name/version: win 10 x64 (18363.900)

Dependencies

# Mandatory:
atomicwrites >=1.2.0           :  1.4.0 (OK)
chardet >=2.0.0                :  3.0.4 (OK)
cloudpickle >=0.5.0            :  1.4.1 (OK)
diff_match_patch >=20181111    :  20181111 (OK)
intervaltree                   :  None (OK)
IPython >=4.0                  :  7.13.0 (OK)
jedi =0.15.2                   :  0.15.2 (OK)
nbconvert >=4.0                :  5.6.1 (OK)
numpydoc >=0.6.0               :  0.9.2 (OK)
paramiko >=2.4.0               :  2.7.1 (OK)
parso =0.5.2                   :  0.5.2 (OK)
pexpect >=4.4.0                :  4.8.0 (OK)
pickleshare >=0.4              :  0.7.5 (OK)
psutil >=5.3                   :  5.7.0 (OK)
pygments >=2.0                 :  2.6.1 (OK)
pylint >=0.25                  :  2.4.4 (OK)
pyls >=0.31.9;<0.32.0          :  0.31.10 (OK)
qdarkstyle >=2.8               :  2.8.1 (OK)
qtawesome >=0.5.7              :  0.7.0 (OK)
qtconsole >=4.6.0              :  4.7.4 (OK)
qtpy >=1.5.0                   :  1.9.0 (OK)
rtree >=0.8.3                  :  0.9.4 (OK)
sphinx >=0.6.6                 :  3.0.4 (OK)
spyder_kernels >=1.9.1;<1.10.0 :  1.9.1 (OK)
watchdog                       :  None (OK)
zmq >=17                       :  18.1.1 (OK)

# Optional:
cython >=0.21                  :  None (OK)
matplotlib >=2.0.0             :  None (OK)
numpy >=1.7                    :  1.18.1 (OK)
pandas >=0.13.1                :  1.0.4 (OK)
scipy >=0.17.0                 :  1.4.1 (OK)
sympy >=0.7.3                  :  None (OK)

[goanpeca]

Hi @colt18, thanks for the request. We will take a look at this in a future release.

Cheers