lossgen: better training, README.md

dnn/torch/lossgen/README.md

@@ -0,0 +1,27 @@
+#Packet loss simulator
+
+This code is an attempt at simulating better packet loss scenarios. The most common way of simulating
+packet loss is to use a random sequence where each packet loss event is uncorrelated with previous events.
+That is a simplistic model since we know that losses often occur in bursts. This model uses real data
+to build a generative model for packet loss.
+
+We use the training data provided for the Audio Deep Packet Loss Concealment Challenge, which is available at:
+
+http://plcchallenge2022pub.blob.core.windows.net/plcchallengearchive/test\_train.tar.gz
+
+To create the training data, run:
+
+`./process_data.sh /<path>/test_train/train/lossy_signals/`
+
+That will create an ascii loss\_sorted.txt file with all loss data sorted in increasing packet loss
+percentage. Then just run:
+
+`python ./train_lossgen.py`
+
+to train a model
+
+To generate a sequence, run
+
+`python3 ./test_lossgen.py <checkpoint> <percentage> output.txt --length 10000`
+
+where <checkpoint> is the .pth model file and <percentage> is the amount of loss (e.g. 0.2 for 20% loss).

dnn/torch/lossgen/train_lossgen.py

@@ -27,9 +27,11 @@ class LossDataset(torch.utils.data.Dataset):
         return self.nb_sequences
 
     def __getitem__(self, index):
-        r0 = np.random.normal(scale=.02, size=(1,1)).astype('float32')
+        r0 = np.random.normal(scale=.1, size=(1,1)).astype('float32')
-        r1 = np.random.normal(scale=.02, size=(self.sequence_length,1)).astype('float32')
+        r1 = np.random.normal(scale=.1, size=(self.sequence_length,1)).astype('float32')
-        return [self.loss[index, :, :], self.perc[index, :, :]+r0+r1]
+        perc = self.perc[index, :, :]
+        perc = perc + (r0+r1)*perc*(1-perc)
+        return [self.loss[index, :, :], perc]
 
 
 adam_betas = [0.8, 0.98]
@@ -61,7 +63,7 @@ scheduler = torch.optim.lr_scheduler.LambdaLR(optimizer=optimizer, lr_lambda=lam
 
 if __name__ == '__main__':
     model.to(device)
-
+    states = None
     for epoch in range(1, epochs + 1):
 
         running_loss = 0
@@ -73,7 +75,8 @@ if __name__ == '__main__':
                 loss = loss.to(device)
                 perc = perc.to(device)
 
-                out, _ = model(loss, perc)
+                out, states = model(loss, perc, states=states)
+                states = [state.detach() for state in states]
                 out = torch.sigmoid(out[:,:-1,:])
                 target = loss[:,1:,:]