def test_batching(): arr = list(range(137)) chunked = list(batch(arr, 5, True)) expected = [[i + k for k in range(5)] for i in range(0, 135, 5)] assert chunked == expected unchunked = list(unbatch(chunked, 5, 0)) assert unchunked == [x for b in expected for x in b] chunked = list(batch(arr, 5, False)) expected = [[i + k for k in range(5)] for i in range(0, 135, 5)] \ + [[135, 136]] assert chunked == expected unchunked = [i for i in unbatch(chunked, 5, len(arr) % 5)] assert unchunked == [x for b in expected for x in b] chunked = list(batch(arr, 5, pad=0, collate_fn=list)) expected = [[i + k for k in range(5)] for i in range(0, 135, 5)] \ + [[135, 136, 0, 0, 0]] assert chunked == expected chunked = batch(arr, 5, pad=0, collate_fn=list) chunked[:1] = [[-1, -2, -3, -4, -5]] chunked[-1] = [-135, -136] assert arr == [-1, -2, -3, -4, -5] + list(range(5, 135)) + [-135, -136]
def predict_fn(feature_sequences): durations = np.array([len(s) for s in feature_sequences[0]]) step = max_time - 2 * warmup # turn sequences chunks = [(i, k, min(d, k + max_time)) for i, d in enumerate(durations) for k in range(0, d - warmup, step)] chunked_sequences = [] for feat in feature_sequences: def get_chunk(i, t1, t2, feat_=feat): return adjust_length(feat_[i][t1:t2], size=max_time, pad=0) chunked_sequences.append(seqtools.starmap(get_chunk, chunks)) chunked_sequences.append([np.int32(t2 - t1) for _, t1, t2 in chunks]) chunked_sequences = seqtools.collate(chunked_sequences) # turn into minibatches null_sample = chunked_sequences[0] n_features = len(null_sample) def collate(b): return [ np.array([b[i][c] for i in range(batch_size)]) for c in range(n_features) ] minibatches = seqtools.batch(chunked_sequences, batch_size, pad=null_sample, collate_fn=collate) # minibatches = seqtools.prefetch( # minibatches, max_cached=nworkers * 5, nworkers=nworkers) # process batched_predictions = seqtools.starmap(predict_batch_fn, minibatches) batched_predictions = seqtools.add_cache(batched_predictions) chunked_predictions = seqtools.unbatch(batched_predictions, batch_size) # recompose out = [ np.empty((d, ) + l_out.output_shape[2:], dtype=np.float32) for d in durations ] for v, (s, start, stop) in zip(chunked_predictions, chunks): skip = warmup if start > 0 else 0 out[s][start + skip:stop] = v[skip:stop - start] return out
def make_sequence(self): """Build a sequence that looks like a dataloader when iterated over.""" # shuffling if self.batch_sampler: batch_indices = list(self.batch_sampler) out = seqtools.smap(lambda bi: [self.dataset[i] for i in bi], batch_indices) elif self.sampler: shuffle_indices = list(self.sampler) out = seqtools.gather(self.dataset, shuffle_indices) elif self.shuffle: shuffle_indices = np.random.permutation(len(self.dataset)) out = seqtools.gather(self.dataset, shuffle_indices) else: out = self.dataset # batch if not self.batch_sampler and self.batch_size is not None: out = seqtools.batch(out, k=self.batch_size, drop_last=self.drop_last, collate_fn=self.collate_fn) elif self.batch_sampler: out = seqtools.smap(self.collate_fn, out) # prefetch if self.num_workers > 0: out = seqtools.prefetch(out, max_buffered=self.num_workers * self.prefetch_factor, nworkers=self.num_workers, method='process', start_hook=self.worker_init_fn, shm_size=self.shm_size) # convert into tensors out = seqtools.smap(into_tensors, out) # pin memory if self.pin_memory: out = seqtools.smap(pin_tensors_memory, out) out = seqtools.prefetch(out, nworkers=1, method='thread', max_buffered=1) return out
loaded_files = seqtools.smap(load, files) loaded_files = seqtools.add_cache(loaded_files, 2) all_samples = seqtools.unbatch(loaded_files, 200, 10) def preprocess(x): t = time.clock() while time.clock() - t < 0.005: pass # busy waiting return x preprocessed_samples = seqtools.smap(preprocess, all_samples) minibatches = seqtools.batch(preprocessed_samples, 64, collate_fn=list) t1 = time.time() for batch in minibatches: pass t2 = time.time() print("sequential read took {:.1f}\"".format(t2 - t1)) t1 = time.time() for batch in seqtools.prefetch(minibatches, max_cached=100, method="thread", nworkers=2): pass t2 = time.time() print("threaded read took {:.1f}\"".format(t2 - t1))
def transfer_feat_seqs(transfer_from, freeze_at): import theano import theano.tensor as T import lasagne from sltools.nn_utils import adjust_length from experiments.utils import reload_best_hmm, reload_best_rnn report = shelve.open(os.path.join(cachedir, transfer_from)) if report['meta']['modality'] == "skel": source_feat_seqs = [skel_feat_seqs] elif report['meta']['modality'] == "bgr": source_feat_seqs = [bgr_feat_seqs] elif report['meta']['modality'] == "fusion": source_feat_seqs = [skel_feat_seqs, bgr_feat_seqs] else: raise ValueError() # no computation required if freeze_at == "inputs": return source_feat_seqs # reuse cached features dump_file = os.path.join( cachedir, report['meta']['experiment_name'] + "_" + freeze_at + "feats.npy") if os.path.exists(dump_file): boundaries = np.stack( (np.cumsum(durations) - durations, np.cumsum(durations)), axis=1) return [split_seq(np.load(dump_file, mmap_mode='r'), boundaries)] # reload model if report['meta']['model'] == "hmm": _, recognizer, _ = reload_best_hmm(report) l_in = recognizer.posterior.l_in if freeze_at == "embedding": l_feats = recognizer.posterior.l_feats elif freeze_at == "logits": l_feats = recognizer.posterior.l_raw elif freeze_at == "posteriors": l_feats = lasagne.layers.NonlinearityLayer( recognizer.posterior.l_out, T.exp) else: raise ValueError() batch_size, max_time, *_ = l_in[0].output_shape # TODO: fragile warmup = recognizer.posterior.warmup else: _, model_dict, _ = reload_best_rnn(report) l_in = model_dict['l_in'] l_feats = model_dict['l_feats'] batch_size, max_time, *_ = l_in[0].output_shape # TODO: fragile warmup = model_dict['warmup'] feats_var = lasagne.layers.get_output(l_feats, deterministic=True) predict_batch_fn = theano.function([l.input_var for l in l_in], feats_var) step = max_time - 2 * warmup # turn sequences into chunks chunks = [(i, k, min(d, k + max_time)) for i, d in enumerate(durations) for k in range(0, d - warmup, step)] chunked_sequences = [] for feat in source_feat_seqs: def get_chunk(i, t1, t2, feat_=feat): return adjust_length(feat_[i][t1:t2], size=max_time, pad=0) chunked_sequences.append(seqtools.starmap(get_chunk, chunks)) chunked_sequences = seqtools.collate(chunked_sequences) # turn into minibatches null_sample = chunked_sequences[0] n_features = len(null_sample) def collate(b): return [ np.array([b[i][c] for i in range(batch_size)]) for c in range(n_features) ] minibatches = seqtools.batch(chunked_sequences, batch_size, pad=null_sample, collate_fn=collate) # minibatches = seqtools.prefetch(minibatches, nworkers=2, max_buffered=10) # process batched_predictions = seqtools.starmap(predict_batch_fn, minibatches) batched_predictions = seqtools.add_cache(batched_predictions) chunked_predictions = seqtools.unbatch(batched_predictions, batch_size) # recompose feat_size = l_feats.output_shape[2:] storage = open_memmap(dump_file, 'w+', dtype=np.float32, shape=(sum(durations), ) + feat_size) subsequences = np.stack( [np.cumsum(durations) - durations, np.cumsum(durations)], axis=1) out_view = seqtools.split(storage, subsequences) for v, (s, start, stop) in zip(chunked_predictions, chunks): skip = warmup if start > 0 else 0 out_view[s][start + skip:stop] = v[skip:stop - start] return [out_view]