1 /* 2 * Copyright (C) 2017 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package com.google.android.exoplayer2.metadata; 17 18 import com.google.android.exoplayer2.Format; 19 import com.google.android.exoplayer2.metadata.emsg.EventMessageDecoder; 20 import com.google.android.exoplayer2.metadata.id3.Id3Decoder; 21 import com.google.android.exoplayer2.metadata.scte35.SpliceInfoDecoder; 22 import com.google.android.exoplayer2.util.MimeTypes; 23 24 /** 25 * A factory for {@link MetadataDecoder} instances. 26 */ 27 public interface MetadataDecoderFactory { 28 29 /** 30 * Returns whether the factory is able to instantiate a {@link MetadataDecoder} for the given 31 * {@link Format}. 32 * 33 * @param format The {@link Format}. 34 * @return Whether the factory can instantiate a suitable {@link MetadataDecoder}. 35 */ supportsFormat(Format format)36 boolean supportsFormat(Format format); 37 38 /** 39 * Creates a {@link MetadataDecoder} for the given {@link Format}. 40 * 41 * @param format The {@link Format}. 42 * @return A new {@link MetadataDecoder}. 43 * @throws IllegalArgumentException If the {@link Format} is not supported. 44 */ createDecoder(Format format)45 MetadataDecoder createDecoder(Format format); 46 47 /** 48 * Default {@link MetadataDecoder} implementation. 49 * <p> 50 * The formats supported by this factory are: 51 * <ul> 52 * <li>ID3 ({@link Id3Decoder})</li> 53 * <li>EMSG ({@link EventMessageDecoder})</li> 54 * <li>SCTE-35 ({@link SpliceInfoDecoder})</li> 55 * </ul> 56 */ 57 MetadataDecoderFactory DEFAULT = new MetadataDecoderFactory() { 58 59 @Override 60 public boolean supportsFormat(Format format) { 61 String mimeType = format.sampleMimeType; 62 return MimeTypes.APPLICATION_ID3.equals(mimeType) 63 || MimeTypes.APPLICATION_EMSG.equals(mimeType) 64 || MimeTypes.APPLICATION_SCTE35.equals(mimeType); 65 } 66 67 @Override 68 public MetadataDecoder createDecoder(Format format) { 69 switch (format.sampleMimeType) { 70 case MimeTypes.APPLICATION_ID3: 71 return new Id3Decoder(); 72 case MimeTypes.APPLICATION_EMSG: 73 return new EventMessageDecoder(); 74 case MimeTypes.APPLICATION_SCTE35: 75 return new SpliceInfoDecoder(); 76 default: 77 throw new IllegalArgumentException("Attempted to create decoder for unsupported format"); 78 } 79 } 80 81 }; 82 83 } 84