ImageView initial time value set incorrectly to 0

[pijyoi]

Short description

If a time-axis is provided to ImageView, the initial position of the yellow line indicating the time position is wrongly set to 0. The actual value should have been the minimum time value.

Code to reproduce

import numpy as np
import pyqtgraph as pg

rng = np.random.default_rng(0)
data_cube = np.empty((9, 100, 100))
xvals = np.arange(data_cube.shape[0]) - data_cube.shape[0]//2

for idx, mu in enumerate(xvals):
    data_cube[idx, ...] = mu + rng.standard_normal(size=data_cube.shape[1:])

pg.mkQApp()
imv = pg.ImageView()
imv.setImage(data_cube, xvals=xvals)
imv.show()
pg.exec()

Expected behavior

In the snippet provided above, the mean value of the data slice is created such that it is equal to the time value.
Thus in the image provided below, the histogram shows that the data slice comes from time -4. However, the yellow time line is at time 0.

Real behavior

Tested environment(s)

• PyQtGraph version: 0.13.3
• Qt Python binding: PySide 6.6.1
• Python version: 3.10.11
• NumPy version: 1.26.2
• Operating system: Windows 10
• Installation method: pip

Additional context

[apoumier]

Hello, we are interested in trying to resolve the issue.