G-API: Align IE Backend with the latest OpenVINO version

[TolyaTalamanov]

Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

• I agree to contribute to the project under Apache 2 License.
• To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
• The PR is proposed to the proper branch
• There is a reference to the original bug report and related work
• There is accuracy test, performance test and test data in opencv_extra repository, if applicable
  Patch to opencv_extra has the same branch name.
• The feature is well documented and sample code can be built with the project CMake

force_builders=Custom
build_image:Custom=ubuntu-openvino-2021.4.2:20.04
test_modules:Custom=gapi,python2,python3,java
buildworker:Custom=linux-1,linux-4
# disabled due high memory usage: test_opencl:Custom=ON
test_opencl:Custom=OFF
test_bigdata:Custom=1
test_filter:Custom=*

[dmatveev]

(Padme meme style): "We have both version tested on CI, right? Right?..."

[TolyaTalamanov]

(Padme meme style): "We have both version tested on CI, right? Right?..."

none of them?

[TolyaTalamanov]

@asmorkalov

Our IE Backend shows these warning during compilation for openvino versions higher than 2023.0
(because we include #<inference_engine.hpp>
Is it fine to leave them or we need to suppress?

warning("The Inference Engine API is deprecated and will be removed in the 2024.0 release. For instructions on transitioning to the new API, please refer to https://docs.openvino.ai/latest/openvino_2_0_transition_guide.html")

warning("The nGraph API is deprecated and will be removed in the 2024.0 release. For instructions on transitioning to the new API, please refer to https://docs.openvino.ai/latest/openvino_2_0_transition_guide.html")

[TolyaTalamanov]

@asmorkalov

Our IE Backend shows these warning during compilation for openvino versions higher than 2023.0 (because we include #<inference_engine.hpp> Is it fine to leave them or we need to suppress?

warning("The Inference Engine API is deprecated and will be removed in the 2024.0 release. For instructions on transitioning to the new API, please refer to https://docs.openvino.ai/latest/openvino_2_0_transition_guide.html")

warning("The nGraph API is deprecated and will be removed in the 2024.0 release. For instructions on transitioning to the new API, please refer to https://docs.openvino.ai/latest/openvino_2_0_transition_guide.html")

I'd rather keep showing these warning to encourage community use new OV2.0 backend.

[TolyaTalamanov]

(Padme meme style): "We have both version tested on CI, right? Right?..."

none of them?

Well, I've tested with both OpenVINO versions seems to be working...

[asmorkalov]

@TolyaTalamanov @dmatveev For now Github actions CI does not provide job with IE. I'll take a look at it after release.
I propose to suppress the warning for now to not bother CI, but file a ticket about the API migration. @opencv-alalek What is your opinion on the warning?

[TolyaTalamanov]

@TolyaTalamanov @dmatveev For now Github actions CI does not provide job with IE. I'll take a look at it after release. I propose to suppress the warning for now to not bother CI, but file a ticket about the API migration. @opencv-alalek What is your opinion on the warning?

Well, we've already migrated to the new API by presenting separate GOVBackend but we still want to keep the legacy API backend which works fine but for OpenVINO 2023.0 it shows warnings...