1 /* 2 * Copyright (C) 2009 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 MEDIA_SOURCE_H_ 18 19 #define MEDIA_SOURCE_H_ 20 21 #include <sys/types.h> 22 23 #include <utils/RefBase.h> 24 25 namespace android { 26 27 class MediaBuffer; 28 class MetaData; 29 30 struct MediaSource : public RefBase { 31 MediaSource(); 32 33 // To be called before any other methods on this object, except 34 // getFormat(). 35 virtual status_t start(MetaData *params = NULL) = 0; 36 37 // Any blocking read call returns immediately with a result of NO_INIT. 38 // It is an error to call any methods other than start after this call 39 // returns. Any buffers the object may be holding onto at the time of 40 // the stop() call are released. 41 // Also, it is imperative that any buffers output by this object and 42 // held onto by callers be released before a call to stop() !!! 43 virtual status_t stop() = 0; 44 45 // Returns the format of the data output by this media source. 46 virtual sp<MetaData> getFormat() = 0; 47 48 struct ReadOptions; 49 50 // Returns a new buffer of data. Call blocks until a 51 // buffer is available, an error is encountered of the end of the stream 52 // is reached. 53 // End of stream is signalled by a result of ERROR_END_OF_STREAM. 54 virtual status_t read( 55 MediaBuffer **buffer, const ReadOptions *options = NULL) = 0; 56 57 // Options that modify read() behaviour. The default is to 58 // a) not request a seek 59 // b) not be late, i.e. lateness_us = 0 60 struct ReadOptions { 61 ReadOptions(); 62 63 // Reset everything back to defaults. 64 void reset(); 65 66 void setSeekTo(int64_t time_us); 67 void clearSeekTo(); 68 bool getSeekTo(int64_t *time_us) const; 69 70 void setLateBy(int64_t lateness_us); 71 int64_t getLateBy() const; 72 73 private: 74 enum Options { 75 kSeekTo_Option = 1, 76 }; 77 78 uint32_t mOptions; 79 int64_t mSeekTimeUs; 80 int64_t mLatenessUs; 81 }; 82 83 protected: 84 virtual ~MediaSource(); 85 86 private: 87 MediaSource(const MediaSource &); 88 MediaSource &operator=(const MediaSource &); 89 }; 90 91 } // namespace android 92 93 #endif // MEDIA_SOURCE_H_ 94