Supply the frame’s content.

diff --git a/src/main/java/net/pterodactylus/sonitus/io/mp3/Frame.java b/src/main/java/net/pterodactylus/sonitus/io/mp3/Frame.java
index ad91a91..b157e2c 100644 (file)
--- a/src/main/java/net/pterodactylus/sonitus/io/mp3/Frame.java
+++ b/src/main/java/net/pterodactylus/sonitus/io/mp3/Frame.java
@@ -17,6 +17,7 @@
 
 package net.pterodactylus.sonitus.io.mp3;
 
+import java.util.Arrays;
 import java.util.Map;
 
 import com.google.common.base.Optional;
@@ -215,6 +216,9 @@ public class Frame {
        /** The decoded emphasis mode. */
        private final int emphasis;
 
+       /** The content of the frame. */
+       private final byte[] content;
+
        /**
         * Creates a new frame from the given values.
         *
@@ -243,7 +247,7 @@ public class Frame {
         * @param emphasis
         *              The emphasis
         */
-       private Frame(int mpegAudioVersionId, int layerDescription, int protectionBit, int bitrateIndex, int samplingRateFrequencyIndex, int paddingBit, int privateBit, int channelMode, int modeExtension, int copyrightBit, int originalBit, int emphasis) {
+       private Frame(int mpegAudioVersionId, int layerDescription, int protectionBit, int bitrateIndex, int samplingRateFrequencyIndex, int paddingBit, int privateBit, int channelMode, int modeExtension, int copyrightBit, int originalBit, int emphasis, byte[] content) {
                this.mpegAudioVersionId = mpegAudioVersionId;
                this.layerDescription = layerDescription;
                this.protectionBit = protectionBit;
@@ -256,6 +260,7 @@ public class Frame {
                this.copyrightBit = copyrightBit;
                this.originalBit = originalBit;
                this.emphasis = emphasis;
+               this.content = content;
        }
 
        //
@@ -363,6 +368,15 @@ public class Frame {
                return Emphasis.values()[emphasis];
        }
 
+       /**
+        * Returns the content of this frame.
+        *
+        * @return The content of this frame
+        */
+       public byte[] content() {
+               return content;
+       }
+
        //
        // STATIC METHODS
        //
@@ -384,6 +398,33 @@ public class Frame {
        }
 
        /**
+        * Calculates the frame length in bytes for the frame starting at the given
+        * offset in the given buffer. This method should only be called for a buffer
+        * and an offset for which {@link #isFrame(byte[], int, int)} returns {@code
+        * true}.
+        *
+        * @param buffer
+        *              The buffer storing the frame
+        * @param offset
+        *              The offset of the frame
+        * @return The length of the frame in bytes, or {@code -1} if the frame length
+        *         can not be calculated
+        */
+       public static int getFrameLength(byte[] buffer, int offset) {
+               MpegAudioVersion mpegAudioVersion = MpegAudioVersion.values()[(buffer[offset + 1] & 0x18) >>> 3];
+               LayerDescription layerDescription = LayerDescription.values()[(buffer[offset + 1] & 0x06) >>> 1];
+               int bitrate = bitrateSupplier.get().get(mpegAudioVersion).get(layerDescription).get((buffer[offset + 2] & 0xf0) >>> 4) * 1000;
+               int samplingRate = samplingRateSupplier.get().get(mpegAudioVersion).get((buffer[offset + 2] & 0x0c) >>> 2);
+               int paddingBit = (buffer[offset + 2] & 0x02) >>> 1;
+               if (layerDescription == LayerDescription.LAYER_1) {
+                       return (12 * bitrate / samplingRate + paddingBit) * 4;
+               } else if ((layerDescription == LayerDescription.LAYER_2) || (layerDescription == LayerDescription.LAYER_3)) {
+                       return 144 * bitrate / samplingRate + paddingBit;
+               }
+               return -1;
+       }
+
+       /**
         * Tries to create an MPEG audio from the given data.
         *
         * @param buffer
@@ -409,7 +450,8 @@ public class Frame {
                        int copyright = (buffer[offset + 3] & 0x08) >> 3;
                        int original = (buffer[offset + 3] & 0x04) >> 2;
                        int emphasis = buffer[offset + 3] & 0x03;
-                       return Optional.of(new Frame(mpegAudioVersionId, layerDescription, protectionBit, bitrateIndex, samplingRateFrequencyIndex, paddingBit, privateBit, channelMode, modeExtension, copyright, original, emphasis));
+                       int frameLength = getFrameLength(buffer, offset);
+                       return Optional.of(new Frame(mpegAudioVersionId, layerDescription, protectionBit, bitrateIndex, samplingRateFrequencyIndex, paddingBit, privateBit, channelMode, modeExtension, copyright, original, emphasis, Arrays.copyOfRange(buffer, 4, frameLength)));
                }
                return Optional.absent();
        }

diff --git a/src/main/java/net/pterodactylus/sonitus/io/mp3/Parser.java b/src/main/java/net/pterodactylus/sonitus/io/mp3/Parser.java
index 55165d8..bbdb5a3 100644 (file)
--- a/src/main/java/net/pterodactylus/sonitus/io/mp3/Parser.java
+++ b/src/main/java/net/pterodactylus/sonitus/io/mp3/Parser.java
@@ -93,9 +93,17 @@ public class Parser {
                        }
                        System.arraycopy(buffer, 1, buffer, 0, 3);
                        buffer[3] = (byte) r;
-                       Optional<Frame> frame = Frame.create(buffer, 0, 4);
-                       if (frame.isPresent()) {
-                               return frame.get();
+                       if (Frame.isFrame(buffer, 0, 4)) {
+                               int frameLength = Frame.getFrameLength(buffer, 0);
+                               if (frameLength != -1) {
+                                       byte[] content = new byte[frameLength + 4];
+                                       readFully(inputStream, content, 4, frameLength);
+                                       System.arraycopy(buffer, 0, content, 0, 4);
+                                       Optional<Frame> frame = Frame.create(content, 0, frameLength + 4);
+                                       if (frame.isPresent()) {
+                                               return frame.get();
+                                       }
+                               }
                        }
                }
        }