DOC: Document and test the torch and tensorflow optional packages

Author: Lee Newberg

README.md

@@ -16,7 +16,9 @@ sudo apt install -y python3-openslide openslide-tools
 pip install histomics_stream 'large_image[openslide]' \
   scikit_image --find-links https://girder.github.io/large_image_wheels
 ```
-Note that additional image readers can be supported by using, e.g., `large_image[openslide,ometiff,openjpeg,bioformats]` instead of `large_image[openslide]`.
+Additional functionality is supported with subpackages, e.g., `histomics_stream[tensorflow,torch,zarr]`. These packages are optional when histomics_stream is used only for masking and/or organizing image tiles into larger image chunks that are more efficient to read than individual image tiles.  However, if you are creating a tensorflow `Dataset` or a pytorch `DataLoader` then you will need the corresponding packages.
+
+Additional image readers can be supported by using, e.g., `large_image[openslide,ometiff,openjpeg,bioformats]` instead of `large_image[openslide]`.
 
 After launching `python3`, import the `histomics_stream` package with:
 

example/pytorch_stream.ipynb

@@ -33,7 +33,7 @@
     "!apt update\n",
     "!apt install -y python3-openslide openslide-tools\n",
     "!pip install 'large_image[openslide,tiff]' --find-links https://girder.github.io/large_image_wheels\n",
-    "!pip install histomics_stream\n",
+    "!pip install histomics_stream[torch]\n",
     "\n",
     "# Get other packages used in this notebook\n",
     "# N.B. itkwidgets works with jupyter<=3.0.0\n",

example/tensorflow_stream.ipynb

@@ -33,7 +33,7 @@
     "!apt update\n",
     "!apt install -y python3-openslide openslide-tools\n",
     "!pip install 'large_image[openslide,tiff]' --find-links https://girder.github.io/large_image_wheels\n",
-    "!pip install histomics_stream\n",
+    "!pip install histomics_stream[tensorflow]\n",
     "\n",
     "# Get other packages used in this notebook\n",
     "# N.B. itkwidgets works with jupyter<=3.0.0\n",