2 Copyright 2004-2005 Chris Tallon
4 This file is part of VOMP.
6 VOMP is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 VOMP is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with VOMP; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
29 ULONG pos_buffer; //position in stream buffer
30 ULONG length; //length of the packet
31 // The fields below are not needed by the MVP
33 ULLONG recording_byte_pos; //position in recording
35 long long presentation_time;/* in 100 ns units*/
42 typedef list<MediaPacket> MediaPacketList;
48 virtual ~DrainTarget();
50 virtual long long SetStartOffset(long long curreftime, bool *rsync)=0;
51 virtual void ResetTimeOffsets()=0;
53 // The following two functions are used by the Stream
54 // to deliver media packets to the front end (DrainTarget).
56 // First, the Stream calls PrepareMediaSample, which gives the front end
57 // read-only access to the Stream's MediaPacketList. PrepareMediaSample should
58 // examine the list to determine how much it wishes to consume, and
59 // should copy any data it requires from the MediaPacket objects into
61 // This function call takes place under a mutex lock to ensure integrity
62 // of the list structure. It should be fast and must not contain any
63 // cancellation points, such as I/O calls for logging.
65 // Second, the Stream releases the mutex and calls DeliverMediaSample.
66 // This function delivers data from the Stream buffer to the presentation
67 // device and returns information to the Stream regarding how many MediaPackets
68 // were consumed. Any data copied from the MediaPackets objects during
69 // PrepareMediaSample is guaranteed by the Stream still to be valid
70 // during the following DeliverMediaSample call.
72 // samplepos is equal to the number of bytes from the first MediaPacket
73 // in the list that have already been consumed in a previous call.
74 virtual void PrepareMediaSample(const MediaPacketList&, UINT samplepos)=0;
76 // The Stream guarantees that the value of *samplepos passed to
77 // DeliverMediaSample will be equal to the value of samplepos passed to
78 // PrepareMediaSample in the previous call.
79 // This function should consume data from the buffer according to the
80 // decisions made in PrepareMediaSample. Its return value and *samplepos
81 // tell the Stream how much data it consumed.
82 // If DeliverMediaSample returns X, the Stream will remove packets 0 to X-1
83 // (inclusive) from the list before the next call.
84 // DeliverMediaSample must also set *samplepos equal to the number of bytes
85 // processed from packet X (usually zero).
86 virtual UINT DeliverMediaSample(const UCHAR* buffer, UINT *samplepos)=0;