Dear all,
We mainly do large scale computer vision task (image classification, retrieval, ...). The pipeline is really great stuff for that. We're trying to reproduce the tutorial given on that topic during the latest spark summit ( http://ampcamp.berkeley.edu/5/exercises/image-classification-with-pipelines.html ) using the master version of spark pipeline and dataframe. The tutorial shows different examples of feature extraction stages before running machine learning algorithms. Even the tutorial is straightforward to reproduce with this new API, we still have some questions : - Can one use external tools (e.g via pipe) as a pipeline stage ? An example of use case is to extract feature learned with convolutional neural network. In our case, this corresponds to a pre-trained neural network with Caffe library (http://caffe.berkeleyvision.org/) . - The second question is about the performance of the pipeline. Library such as Caffe processes the data in batch and instancing one Caffe network can be time consuming when this network is very deep. So, we can gain performance if we minimize the number of Caffe network creation and give data in batch to the network. In the pipeline, this corresponds to run transformers that work on a partition basis and give the whole partition to a single caffe network. How can we create such a transformer ? Best, Jao
