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 <media/stagefright/MediaErrors.h> 24 #include <utils/RefBase.h> 25 #include <utils/Vector.h> 26 27 namespace android { 28 29 class MediaBuffer; 30 class MetaData; 31 32 struct MediaSource : public virtual RefBase { 33 MediaSource(); 34 35 // To be called before any other methods on this object, except 36 // getFormat(). 37 virtual status_t start(MetaData *params = NULL) = 0; 38 39 // Any blocking read call returns immediately with a result of NO_INIT. 40 // It is an error to call any methods other than start after this call 41 // returns. Any buffers the object may be holding onto at the time of 42 // the stop() call are released. 43 // Also, it is imperative that any buffers output by this object and 44 // held onto by callers be released before a call to stop() !!! 45 virtual status_t stop() = 0; 46 47 // Returns the format of the data output by this media source. 48 virtual sp<MetaData> getFormat() = 0; 49 50 struct ReadOptions; 51 52 // Returns a new buffer of data. Call blocks until a 53 // buffer is available, an error is encountered of the end of the stream 54 // is reached. 55 // End of stream is signalled by a result of ERROR_END_OF_STREAM. 56 // A result of INFO_FORMAT_CHANGED indicates that the format of this 57 // MediaSource has changed mid-stream, the client can continue reading 58 // but should be prepared for buffers of the new configuration. 59 virtual status_t read( 60 MediaBuffer **buffer, const ReadOptions *options = NULL) = 0; 61 62 // Options that modify read() behaviour. The default is to 63 // a) not request a seek 64 // b) not be late, i.e. lateness_us = 0 65 struct ReadOptions { 66 enum SeekMode { 67 SEEK_PREVIOUS_SYNC, 68 SEEK_NEXT_SYNC, 69 SEEK_CLOSEST_SYNC, 70 SEEK_CLOSEST, 71 }; 72 73 ReadOptions(); 74 75 // Reset everything back to defaults. 76 void reset(); 77 78 void setSeekTo(int64_t time_us, SeekMode mode = SEEK_CLOSEST_SYNC); 79 void clearSeekTo(); 80 bool getSeekTo(int64_t *time_us, SeekMode *mode) const; 81 82 void setLateBy(int64_t lateness_us); 83 int64_t getLateBy() const; 84 85 private: 86 enum Options { 87 kSeekTo_Option = 1, 88 }; 89 90 uint32_t mOptions; 91 int64_t mSeekTimeUs; 92 SeekMode mSeekMode; 93 int64_t mLatenessUs; 94 }; 95 96 // Causes this source to suspend pulling data from its upstream source 97 // until a subsequent read-with-seek. Currently only supported by 98 // OMXCodec. pauseMediaSource99 virtual status_t pause() { 100 return ERROR_UNSUPPORTED; 101 } 102 103 // The consumer of this media source requests that the given buffers 104 // are to be returned exclusively in response to read calls. 105 // This will be called after a successful start() and before the 106 // first read() call. 107 // Callee assumes ownership of the buffers if no error is returned. setBuffersMediaSource108 virtual status_t setBuffers(const Vector<MediaBuffer *> &buffers) { 109 return ERROR_UNSUPPORTED; 110 } 111 112 protected: 113 virtual ~MediaSource(); 114 115 private: 116 MediaSource(const MediaSource &); 117 MediaSource &operator=(const MediaSource &); 118 }; 119 120 } // namespace android 121 122 #endif // MEDIA_SOURCE_H_ 123