Recipe improvements

[h-vetinari]

Some open points remaining from (OP of) #12:

• build with cuda
• build with ffmpeg support
• turn into multi-output recipe (e.g. with/without ffmpeg/image support)?
• package c++ lib separately?
• build for osx
• build for win
• double-check PTX vs. cuda-arches, see this comment
• depend on pillow-simd, see Package pillow-simd? pillow-feedstock#103
• Split test files into a separate packages to reduce download size from 7MB to 1MB

CC @hmaarrfk @isuruf

[hmaarrfk]

Thoughts:

• build with ffmpeg support
  Sure

• turn into multi-output recipe (e.g. with/without ffmpeg/image support)?
  Yes

• package c++ lib separately?
  Maybe just create a split package and have the lib package not depend on python https://github.com/conda-forge/opencv-feedstock/blob/master/recipe/meta.yaml#L1

• build for osx
  Thanks!!!!

• build for win

Didn't know this was dropped but good to keep track!

[h-vetinari]

package c++ lib separately?

Maybe just create a split package and have the lib package not depend on python https://github.com/conda-forge/opencv-feedstock/blob/master/recipe/meta.yaml#L1

That's (another aspect of) what I meant by making the recipe have multiple outputs

build for osx

Thanks!!!!

That credit belongs to @isuruf

build for win

Didn't know this was dropped but good to keep track!

When I picked up the feedstock again, linux was the only build variant... Not sure how much effort this would be, but the pytorch channel has windows builds (even with cuda).

[hmaarrfk]

Also cross referencing this issue:
conda-forge/pytorch-cpu-feedstock#40 (comment)

[Tobias-Fischer]

It would also be great if the correct version of pytorch is being pinned. Currently there can be a mismatch between the pytorch and torchvision versions. The compatibility table is shown in their GitHub repo

[hmaarrfk]

As test files are being copied into the recipe archive, the many binary files are actually increasing the size of said archive: