def to_image_list()

in src/MaskRCNNDetection/maskrcnn_benchmark/structures/image_list.py [0:0]

• 26 lines of code
• 13 McCabe index (conditional complexity)

def to_image_list(tensors, size_divisible=0):
    """
    tensors can be an ImageList, a torch.Tensor or
    an iterable of Tensors. It can't be a numpy array.
    When tensors is an iterable of Tensors, it pads
    the Tensors with zeros so that they have the same
    shape
    """
    if isinstance(tensors, torch.Tensor) and size_divisible > 0:
        tensors = [tensors]

    if isinstance(tensors, ImageList):
        return tensors
    elif isinstance(tensors, torch.Tensor):
        # single tensor shape can be inferred
        assert tensors.dim() == 4
        image_sizes = [tensor.shape[-2:] for tensor in tensors]
        return ImageList(tensors, image_sizes)
    elif isinstance(tensors, (tuple, list)):
        max_size = tuple(max(s) for s in zip(*[img.shape for img in tensors]))

        # TODO Ideally, just remove this and let me model handle arbitrary
        # input sizs
        if size_divisible > 0:
            import math

            stride = size_divisible
            max_size = list(max_size)
            max_size[1] = int(math.ceil(max_size[1] / stride) * stride)
            max_size[2] = int(math.ceil(max_size[2] / stride) * stride)
            max_size = tuple(max_size)

        batch_shape = (len(tensors),) + max_size
        batched_imgs = tensors[0].new(*batch_shape).zero_()
        for img, pad_img in zip(tensors, batched_imgs):
            pad_img[: img.shape[0], : img.shape[1], : img.shape[2]].copy_(img)

        image_sizes = [im.shape[-2:] for im in tensors]

        return ImageList(batched_imgs, image_sizes)
    else:
        raise TypeError("Unsupported type for to_image_list: {}".format(type(tensors)))