Writer

Writer can be used to pack all output produced by BlenderProc into a specific format.

HDF5 Writer

By using bproc.writer.write_hdf5, all given data corresponding to the same frame is packed into one .hdf5 file. This has the advantage that all data is compressed and the data of different frames cannot get mixed up.

To visualize a given hdf5 file, you can use BlenderProcs CLI:

blenderproc vis hdf5 <path_to_file>

If you want to read .hdf5 files in your data processing code, you can make use of the h5py python package:

import h5py
with h5py.File("myfile.hdf5") as f:
    colors = np.array(f["colors"])

To read in json strings saved in the hdf5 File (e.g. object poses), you can make use of the following snippet:

text = np.array(f["object_states"]).tostring()
obj_states = json.loads(text)

Coco Writer

Via bproc_writer.write_coco_annotations, rendered instance segmentations are written in the COCO format. Read more about the specifications of this format here

To visualize a frame written in the COCO format, you can use BlenderProcs CLI:

blenderproc vis coco <path_to_file>

BOP Writer

With bproc.writer.write_bop, depth and RGB images, as well as camera intrinsics and extrinsics are stored in a BOP dataset. Read more about the specifications of the BOP format here

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Next tutorial: How key frames work