Commits on Jan 11, 2020

1. Extend image blending module …

   With this patch the available augmenters for
   alpha-blending of images are significantly extended.
   There are now new blending augmenters available to
   alpha-blend acoording to:
   * Some randomly chosen colors. (`BlendAlphaSomeColors`)
   * Linear gradients. (`BlendAlphaHorizontalLinearGradient`,
     `BlendAlphaVerticalLinearGradient`)
   * Regular grids and checkerboard patterns. (`BlendAlphaRegularGrid`,
     `BlendAlphaCheckerboard`)
   * Only at locations that overlap with specific segmentation class
     IDs (or the inverse of that). (`BlendAlphaSegMapClassIds`)
   * Only within bounding boxes with specific labels (or the inverse
     of that). (`BlendAlphaBoundingBoxes`)
   
   This allows to e.g. randomly remove some colors while leaving
   other colors unchanged (`BlendAlphaSomeColors(Grayscale(1.0))`),
   to change the color of some objects
   (`BlendAlphaSegMapClassIds(AddToHue((-256, 256)))`), to add
   cloud-patterns only to the top of images
   (`BlendAlphaVerticalLinearGradient(Clouds())`) or to apply
   augmenters in some coarse rectangular areas (e.g.
   `BlendAlphaRegularGrid(Multiply(0.0))` to achieve a similar
   effect to `CoarseDropout` or
   `BlendAlphaRegularGrid(AveragePooling(8))` to pool in equally
   coarse image sub-regions).
   
   Other mask-based alpha blending techniques can be achieved by
   subclassing `IBatchwiseMaskGenerator` and providing an
   instance of such a class to `BlendAlphaMask`.
   
   This patch also changes the naming of the blending augmenters
   as follows:
   * `Alpha` -> `BlendAlpha`
   * `AlphaElementwise` -> `BlendAlphaElementwise`
   * `SimplexNoiseAlpha` -> `BlendAlphaSimplexNoise`
   * `FrequencyNoiseAlpha` -> `BlendAlphaFrequencyNoise`
   The old names are now deprecated.
   Furthermore, the parameters `first` and `second`, which were
   used by all blending augmenters, have now the names `foreground`
   and `background`.
   
   List of changes:
   * Add `imgaug.augmenters.blend.BlendAlphaMask`, which uses
     a mask generator instance to generate per batch alpha masks and
     then alpha-blends using these masks.
   * Add `imgaug.augmenters.blend.BlendAlphaSomeColors`.
   * Add `imgaug.augmenters.blend.BlendAlphaHorizontalLinearGradient`.
   * Add `imgaug.augmenters.blend.BlendAlphaVerticalLinearGradient`.
   * Add `imgaug.augmenters.blend.BlendAlphaRegularGrid`.
   * Add `imgaug.augmenters.blend.BlendAlphaCheckerboard`.
   * Add `imgaug.augmenters.blend.BlendAlphaSegMapClassIds`.
   * Add `imgaug.augmenters.blend.BlendAlphaBoundingBoxes`.
   * Add `imgaug.augmenters.blend.IBatchwiseMaskGenerator`,
     an interface for classes generating masks on a batch-by-batch
     basis.
   * Add `imgaug.augmenters.blend.StochasticParameterMaskGen`,
     a helper to generate masks from `StochasticParameter` instances.
   * Add `imgaug.augmenters.blend.SomeColorsMaskGen`, a generator
     that produces masks marking randomly chosen colors in images.
   * Add `imgaug.augmenters.blend.HorizontalLinearGradientMaskGen`,
     a linear gradient mask generator.
   * Add `imgaug.augmenters.blend.VerticalLinearGradientMaskGen`,
     a linear gradient mask generator.
   * Add `imgaug.augmenters.blend.RegularGridMaskGen`,
     a checkerboard-like mask generator where every grid cell has
     a random alpha value.
   * Add `imgaug.augmenters.blend.CheckerboardMaskGen`,
     a checkerboard-like mask generator where every grid cell has
     the opposite alpha value of its 4-neighbours.
   * Add `imgaug.augmenters.blend.SegMapClassIdsMaskGen`, a
     segmentation map-based mask generator.
   * Add `imgaug.augmenters.blend.BoundingBoxesMaskGen`, a bounding
     box-based mask generator.
   * Add `imgaug.augmenters.blend.InvertMaskGen`, an mask generator
     that inverts masks produces by child generators.
   * Change `imgaug.parameters.SimplexNoise` and
     `imgaug.parameters.FrequencyNoise` to also accept `(H, W, C)`
     sampling shapes, instead of only `(H, W)`.
   * Refactor `AlphaElementwise` to be a wrapper around
     `BlendAlphaMask`.
   * Rename `Alpha` to `BlendAlpha`.
     `Alpha` is now deprecated.
   * Rename `AlphaElementwise` to `BlendAlphaElementwise`.
     `AlphaElementwise` is now deprecated.
   * Rename `SimplexNoiseAlpha` to `BlendAlphaSimplexNoise`.
     `SimplexNoiseAlpha` is now deprecated.
   * Rename `FrequencyNoiseAlpha` to `BlendAlphaFrequencyNoise`.
     `FrequencyNoiseAlpha` is now deprecated.
   * Rename arguments `first` and `second` to `foreground` and
     `background` in `BlendAlpha`, `BlendAlphaElementwise`,
     `BlendAlphaSimplexNoise` and `BlendAlphaFrequencyNoise`.
   * Change `imgaug.parameters.handle_categorical_string_param()`
     to allow parameter `valid_values` to be `None`.
   * Fix a wrong error message in
     `imgaug.augmenters.color.change_colorspace_()`.
   * Remove `imgaug.augmenters.color.GrayscaleColorwise`
     and `imgaug.augmenters.color.RemoveSaturationColorwise`
     as these are now covered by `BlendAlphaSomeColors`.

   

   aleju committed Jan 11, 2020
   Configuration menu

   • View commit details
   • Copy full SHA for 2466733
   • Browse repository at this point

   Copy the full SHA

   2466733 View commit details

   Browse the repository at this point in the history