I find no references on what this error means when code exits the with group:

with h5py.File(image_path, driver='core', backing_store=True, mode='w') as h5image:
	ds = h5image.create_dataset('Images', shape=(rows,width,height,depth), dtype=str(images[0].dtype))
	for cnt, image in enumerate(images):
		ds[cnt:cnt+1,:,:] = image
Error Message:

OSError: Can’t write data (no appropriate function for conversion path)
Stack Trace:

h5py\_objects.pyx:54: in h5py._objects.with_phil.wrapper ??? h5py\_objects.pyx:55: in h5py._objects.with_phil.wrapper ??? ..\art\art-repo\venv\Lib\site-packages\h5py\_hl\dataset.py:708: in __setitem__ self.id.write(mspace, fspace, val, mtype, dxpl=self._dxpl) h5py\_objects.pyx:54: in h5py._objects.with_phil.wrapper ??? h5py\_objects.pyx:55: in h5py._objects.with_phil.wrapper ??? h5py\h5d.pyx:222: in h5py.h5d.DatasetID.write ??? h5py\_proxy.pyx:132: in h5py._proxy.dset_rw ???
Appreciate any help that someone could provide on what is wrong.
Environment:

Windows 10 Pro

Python 3.7.3

h5py 3.1.0

numpy 1.19.1

pandas 1.1.1
Examining the C code in  HDF5-1_12_0-alpha0 tag which is the last version prior to the Nov 6, 2020 h5py release I found in H5T.c only one instance of message containing “no appropriate function for conversion path” line 4826:
    if(!path->conv.u.app_func)
    HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, NULL, "no appropriate function for conversion path")
What I do not understand is why it is looking for a function.  The data being written is standard image data at 1080x1080x3 of uint8 data.
Thanks
              
Hi @john3.16,
What’s the value of str(images[0].dtype)? What are the type and shape of the image variable in the for loop?
Aleksandar
              
And the ds shape is (rows, 1080, 1080, 3)?
Have you tried ds[cnt:cnt+1,:,:,:] in the assignment?
That conversion path error typically means that for some reason the HDF5 library did not know how to convert between the HDF5 datatypes of the ds and the image values. Your answers imply that ds.dtype and image.dtype should be the same and equivalent to numpy.dtype('uint8'). If so, I think your example code should work.
Aleksandar
              
Adding that last ,: did the trick.  It no longer errors out.
Thought it would store the image but looks more like a grid:
image811×185 2.58 KB
              
Fix the dimensions issue by dropping rows from the shape parm
			with h5py.File(image_path, driver='core', backing_store=True, mode='w') as h5image:
			ds = h5image.create_dataset('Images', shape=(width,height,depth), dtype=str(images[0].dtype))
			for cnt, image in enumerate(images):
				ds[cnt:cnt+1,:,:,:] = image
I thought HDFView would show me the image though.
              
There is a convention or attributes that must be attached to the dataset in order for hdfview to recognize the dataset as images - are those there.

4 dims indicates there a multiple images. (I think).
allen
              
Got working with this and I see my images in HDFViewer
		with h5py.File(image_path, driver='core', backing_store=True, mode='w') as h5image:
			for cnt, image in enumerate(images):
				ds = h5image.create_dataset(f'Images_{cnt+1:03}', data=image, dtype=image_dtype, shape=(width,height,depth))