Add webp decoder

[NicolasHug]

This PR adds the decode_webp() function. We dynamically link against libwebp which is BSD3. We only support RGB images. RGBA webp images can be decoded, the transparency channel is ignored.

[pytorch-bot]

🔗 Helpful Links

🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/vision/8527

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❌ 10 New Failures, 13 Pending, 14 Unrelated Failures

As of commit b7bf5a7 with merge base edb1c33 ():

NEW FAILURES - The following jobs have failed:

• CMake / macos (macos-m1-stable) / macos-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• CMake / windows (windows.g5.4xlarge.nvidia.gpu, cuda, 11.8) / windows-job (gh)
  The process 'C:\Program Files\Git\cmd\git.exe' failed with exit code 128
• Tests / unittests-macos (3.10, macos-m1-stable) / macos-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Tests / unittests-macos (3.11, macos-m1-stable) / macos-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Tests / unittests-macos (3.9, macos-m1-stable) / macos-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Tests / unittests-windows (3.10, windows.4xlarge, cpu) / windows-job (gh)
  The process 'C:\Program Files\Git\cmd\git.exe' failed with exit code 128
• Tests / unittests-windows (3.11, windows.4xlarge, cpu) / windows-job (gh)
  The process 'C:\Program Files\Git\cmd\git.exe' failed with exit code 128
• Tests / unittests-windows (3.12, windows.4xlarge, cpu) / windows-job (gh)
  The process 'C:\Program Files\Git\cmd\git.exe' failed with exit code 128
• Tests / unittests-windows (3.9, windows.4xlarge, cpu) / windows-job (gh)
  The process 'C:\Program Files\Git\cmd\git.exe' failed with exit code 128
• Tests / unittests-windows (3.9, windows.g5.4xlarge.nvidia.gpu, cuda, 11.8) / windows-job (gh)
  The process 'C:\Program Files\Git\cmd\git.exe' failed with exit code 128

FLAKY - The following jobs failed but were likely due to flakiness present on trunk:

• CMake / linux (linux.12xlarge, cpu) / linux-job (gh) (matched linux rule in flaky-rules.json)
  The process '/usr/bin/git' failed with exit code 128
• CMake / linux (linux.g5.4xlarge.nvidia.gpu, cuda, 11.8) / linux-job (gh) (matched linux rule in flaky-rules.json)
  The process '/usr/bin/git' failed with exit code 128
• CMake / windows (windows.4xlarge, cpu) / windows-job (gh) (detected as infra flaky with no log or failing log classifier)
• Docs / build / linux-job (gh) (similar failure)
• Lint / c-source / linux-job (gh) (matched linux rule in flaky-rules.json)
  The process '/usr/bin/git' failed with exit code 128
• Lint / python-source-and-configs / linux-job (gh) (matched linux rule in flaky-rules.json)
  The process '/usr/bin/git' failed with exit code 128
• Lint / python-types / linux-job (gh) (similar failure)
• Tests / onnx / linux-job (gh) (matched linux rule in flaky-rules.json)
  The process '/usr/bin/git' failed with exit code 128
• Tests / unittests-linux (3.10, linux.12xlarge, cpu) / linux-job (gh) (matched linux rule in flaky-rules.json)
  The process '/usr/bin/git' failed with exit code 128
• Tests / unittests-linux (3.11, linux.12xlarge, cpu) / linux-job (gh) (matched linux rule in flaky-rules.json)
  The process '/usr/bin/git' failed with exit code 128
• Tests / unittests-linux (3.12, linux.12xlarge, cpu) / linux-job (gh) (matched linux rule in flaky-rules.json)
  The process '/usr/bin/git' failed with exit code 128
• Tests / unittests-linux (3.9, linux.12xlarge, cpu) / linux-job (gh) (matched linux rule in flaky-rules.json)
  The process '/usr/bin/git' failed with exit code 128
• Tests / unittests-linux (3.9, linux.g5.4xlarge.nvidia.gpu, cuda, 11.8) / linux-job (gh) (matched linux rule in flaky-rules.json)
  The process '/usr/bin/git' failed with exit code 128
• Tests / unittests-macos (3.12, macos-m1-stable) / macos-job (gh) (detected as infra flaky with no log or failing log classifier)

This comment was automatically generated by Dr. CI and updates every 15 minutes.

[NicolasHug]

OK, M1 jobs seem to all be passing now.

[NicolasHug]

All Windows tests, wheels and conda builds passing

[github-actions]

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