add some code

managed_components/78__esp-opus/dnn/training_tf2/fec_packets.py

@@ -0,0 +1,108 @@
+"""
+/* Copyright (c) 2022 Amazon
+   Written by Jan Buethe */
+/*
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions
+   are met:
+
+   - Redistributions of source code must retain the above copyright
+   notice, this list of conditions and the following disclaimer.
+
+   - Redistributions in binary form must reproduce the above copyright
+   notice, this list of conditions and the following disclaimer in the
+   documentation and/or other materials provided with the distribution.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
+   OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+"""
+
+import numpy as np
+
+
+
+def write_fec_packets(filename, packets, rates=None):
+    """ writes packets in binary format """
+
+    assert np.dtype(np.float32).itemsize == 4
+    assert np.dtype(np.int16).itemsize == 2
+
+    # derive some sizes
+    num_packets             = len(packets)
+    subframes_per_packet    = packets[0].shape[-2]
+    num_features            = packets[0].shape[-1]
+
+    # size of float is 4
+    subframe_size           = num_features * 4
+    packet_size             = subframe_size * subframes_per_packet + 2 # two bytes for rate
+
+    version = 1
+    # header size (version, header_size, num_packets, packet_size, subframe_size, subrames_per_packet, num_features)
+    header_size = 14
+
+    with open(filename, 'wb') as f:
+
+        # header
+        f.write(np.int16(version).tobytes())
+        f.write(np.int16(header_size).tobytes())
+        f.write(np.int16(num_packets).tobytes())
+        f.write(np.int16(packet_size).tobytes())
+        f.write(np.int16(subframe_size).tobytes())
+        f.write(np.int16(subframes_per_packet).tobytes())
+        f.write(np.int16(num_features).tobytes())
+
+        # packets
+        for i, packet in enumerate(packets):
+            if type(rates) == type(None):
+                rate = 0
+            else:
+                rate = rates[i]
+
+            f.write(np.int16(rate).tobytes())
+
+            features = np.flip(packet, axis=-2)
+            f.write(features.astype(np.float32).tobytes())
+
+
+def read_fec_packets(filename):
+    """ reads packets from binary format """
+
+    assert np.dtype(np.float32).itemsize == 4
+    assert np.dtype(np.int16).itemsize == 2
+
+    with open(filename, 'rb') as f:
+
+        # header
+        version                 = np.frombuffer(f.read(2), dtype=np.int16).item()
+        header_size             = np.frombuffer(f.read(2), dtype=np.int16).item()
+        num_packets             = np.frombuffer(f.read(2), dtype=np.int16).item()
+        packet_size             = np.frombuffer(f.read(2), dtype=np.int16).item()
+        subframe_size           = np.frombuffer(f.read(2), dtype=np.int16).item()
+        subframes_per_packet    = np.frombuffer(f.read(2), dtype=np.int16).item()
+        num_features            = np.frombuffer(f.read(2), dtype=np.int16).item()
+
+        dummy_features          = np.zeros((1, subframes_per_packet, num_features), dtype=np.float32)
+
+        # packets
+        rates = []
+        packets = []
+        for i in range(num_packets):
+
+            rate = np.frombuffer(f.read(2), dtype=np.int16).item
+            rates.append(rate)
+
+            features = np.reshape(np.frombuffer(f.read(subframe_size * subframes_per_packet), dtype=np.float32), dummy_features.shape)
+            packet = np.flip(features, axis=-2)
+            packets.append(packet)
+
+    return packets