Dali: Load image from a binary file

[Vert53]

Hi, I want to load an image that is saved in a binary file and implement myself the loading part. So instead of define_graph having for example: FileReader, ImageDecoder, op, I will have loading of the file to numpy (for example numpy.fromfile) and then the op.
Is such thing possible?
example:
def define_graph(self): numpy.fromfile(self.image_path, dtype=float32).reshape(100,100,3,1) images = self.crop_mirror_normalize_0(images)

Thanks,
Vert

[JanuszL]

Hi,
You can use NumpyReader operator, ExternalSource or implement a custom operator in Python.

[Vert53]

Hi,
You can use NumpyReader operator, ExternalSource or implement a custom operator in Python.

ExternalSource works perfectly. Thanks.

I created a base class to be subclassed and ops can be added.
here's the code:

class PipeLineExternalSource(Pipeline, ABC):
    def __init__(self, batch_size, num_threads, device_id,
                 data: Iterable[np.ndarray], layout='HWC'):
        """
        data is an iterable of batches of data.
        So it can be an iterator that returns a batch of data every time __next__ is called.
        Or it can be a list with one batch of a single image:  [np.ndarray] where np.ndarray is of shape ()
        """
        super().__init__(batch_size, num_threads, device_id, seed=12)
        self.source = ops.ExternalSource(source=data, layout=layout)