1 /* 2 * Copyright (C) 2012 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 17 #ifndef TIMED_TEXT_SRT_SOURCE_H_ 18 #define TIMED_TEXT_SRT_SOURCE_H_ 19 20 #include <media/stagefright/MediaErrors.h> 21 #include <media/stagefright/MediaSource.h> 22 #include <utils/Compat.h> // off64_t 23 24 #include "TimedTextSource.h" 25 26 namespace android { 27 28 class AString; 29 class DataSource; 30 class MediaBuffer; 31 class Parcel; 32 33 class TimedTextSRTSource : public TimedTextSource { 34 public: 35 TimedTextSRTSource(const sp<DataSource>& dataSource); 36 virtual status_t start(); 37 virtual status_t stop(); 38 virtual status_t read( 39 int64_t *startTimeUs, 40 int64_t *endTimeUs, 41 Parcel *parcel, 42 const MediaSource::ReadOptions *options = NULL); 43 virtual sp<MetaData> getFormat(); 44 45 protected: 46 virtual ~TimedTextSRTSource(); 47 48 private: 49 sp<DataSource> mSource; 50 sp<MetaData> mMetaData; 51 52 struct TextInfo { 53 int64_t endTimeUs; 54 // The offset of the text in the original file. 55 off64_t offset; 56 int textLen; 57 }; 58 59 size_t mIndex; 60 KeyedVector<int64_t, TextInfo> mTextVector; 61 62 void reset(); 63 status_t scanFile(); 64 status_t getNextSubtitleInfo( 65 off64_t *offset, int64_t *startTimeUs, TextInfo *info); 66 status_t readNextLine(off64_t *offset, AString *data); 67 status_t getText( 68 const MediaSource::ReadOptions *options, 69 AString *text, int64_t *startTimeUs, int64_t *endTimeUs); 70 status_t extractAndAppendLocalDescriptions( 71 int64_t timeUs, const AString &text, Parcel *parcel); 72 73 // Compares the time range of the subtitle at index to the given timeUs. 74 // The time range of the subtitle to match with given timeUs is extended to 75 // [endTimeUs of the previous subtitle, endTimeUs of current subtitle). 76 // 77 // This compare function is used to find a next subtitle when read() is 78 // called with seek options. Note that timeUs within gap ranges, such as 79 // [200, 300) in the below example, will be matched to the closest future 80 // subtitle, [300, 400). 81 // 82 // For instance, assuming there are 3 subtitles in mTextVector, 83 // 0: [100, 200) ----> [0, 200) 84 // 1: [300, 400) ----> [200, 400) 85 // 2: [500, 600) ----> [400, 600) 86 // If the 'index' parameter contains 1, this function 87 // returns 0, if timeUs is in [200, 400) 88 // returns -1, if timeUs >= 400, 89 // returns 1, if timeUs < 200. 90 int compareExtendedRangeAndTime(size_t index, int64_t timeUs); 91 92 DISALLOW_EVIL_CONSTRUCTORS(TimedTextSRTSource); 93 }; 94 95 } // namespace android 96 97 #endif // TIMED_TEXT_SRT_SOURCE_H_ 98