1 files changed, 92 insertions, 0 deletions
diff --git a/Ryujinx.HLE/HOS/Services/Audio/HardwareOpusDecoderManager/DecoderCommon.cs b/Ryujinx.HLE/HOS/Services/Audio/HardwareOpusDecoderManager/DecoderCommon.cs
new file mode 100644
index 00000000..944541cc
--- /dev/null
+++ b/Ryujinx.HLE/HOS/Services/Audio/HardwareOpusDecoderManager/DecoderCommon.cs
@@ -0,0 +1,92 @@
+using Concentus;
+using Concentus.Enums;
+using Concentus.Structs;
+using Ryujinx.HLE.HOS.Services.Audio.Types;
+using System;
+using System.Runtime.CompilerServices;
+
+namespace Ryujinx.HLE.HOS.Services.Audio.HardwareOpusDecoderManager
+{
+    static class DecoderCommon
+    {
+        private static ResultCode GetPacketNumSamples(this IDecoder decoder, out int numSamples, byte[] packet)
+        {
+            int result = OpusPacketInfo.GetNumSamples(packet, 0, packet.Length, decoder.SampleRate);
+
+            numSamples = result;
+
+            if (result == OpusError.OPUS_INVALID_PACKET)
+            {
+                return ResultCode.OpusInvalidInput;
+            }
+            else if (result == OpusError.OPUS_BAD_ARG)
+            {
+                return ResultCode.OpusInvalidInput;
+            }
+
+            return ResultCode.Success;
+        }
+
+        public static ResultCode DecodeInterleaved(
+            this IDecoder decoder,
+            bool reset,
+            ReadOnlySpan<byte> input,
+            out short[] outPcmData,
+            ulong outputSize,
+            out uint outConsumed,
+            out int outSamples)
+        {
+            outPcmData = null;
+            outConsumed = 0;
+            outSamples = 0;
+
+            int streamSize = input.Length;
+
+            if (streamSize < Unsafe.SizeOf<OpusPacketHeader>())
+            {
+                return ResultCode.OpusInvalidInput;
+            }
+
+            OpusPacketHeader header = OpusPacketHeader.FromSpan(input);
+            int headerSize = Unsafe.SizeOf<OpusPacketHeader>();
+            uint totalSize = header.length + (uint)headerSize;
+
+            if (totalSize > streamSize)
+            {
+                return ResultCode.OpusInvalidInput;
+            }
+
+            byte[] opusData = input.Slice(headerSize, (int)header.length).ToArray();
+
+            ResultCode result = decoder.GetPacketNumSamples(out int numSamples, opusData);
+
+            if (result == ResultCode.Success)
+            {
+                if ((uint)numSamples * (uint)decoder.ChannelsCount * sizeof(short) > outputSize)
+                {
+                    return ResultCode.OpusInvalidInput;
+                }
+
+                outPcmData = new short[numSamples * decoder.ChannelsCount];
+
+                if (reset)
+                {
+                    decoder.ResetState();
+                }
+
+                try
+                {
+                    outSamples = decoder.Decode(opusData, 0, opusData.Length, outPcmData, 0, outPcmData.Length / decoder.ChannelsCount);
+                    outConsumed = totalSize;
+                }
+                catch (OpusException)
+                {
+                    // TODO: as OpusException doesn't provide us the exact error code, this is kind of inaccurate in some cases...
+                    return ResultCode.OpusInvalidInput;
+                }
+            }
+
+            return ResultCode.Success;
+        }
+    }
+}
+\ No newline at end of file