WebMElement.c revision 538f6170b788de7408b06efc6613dc98579aa6a6 
1// Copyright (c) 2010 The WebM project authors. All Rights Reserved.
2//
3// Use of this source code is governed by a BSD-style license
4// that can be found in the LICENSE file in the root of the source
5// tree. An additional intellectual property rights grant can be found
6// in the file PATENTS.  All contributing project authors may
7// be found in the AUTHORS file in the root of the source tree.
8
9
10#include "EbmlBufferWriter.h"
11#include "EbmlIDs.h"
12#include "WebMElement.h"
13#include <stdio.h>
14
15#define kVorbisPrivateMaxSize  4000
16
17void writeHeader(EbmlGlobal *glob)
18{
19    EbmlLoc start;
20    Ebml_StartSubElement(glob, &start, EBML);
21    Ebml_SerializeUnsigned(glob, EBMLVersion, 1);
22    Ebml_SerializeUnsigned(glob, EBMLReadVersion, 1); //EBML Read Version
23    Ebml_SerializeUnsigned(glob, EBMLMaxIDLength, 4); //EBML Max ID Length
24    Ebml_SerializeUnsigned(glob, EBMLMaxSizeLength, 8); //EBML Max Size Length
25    Ebml_SerializeString(glob, DocType, "webm"); //Doc Type
26    Ebml_SerializeUnsigned(glob, DocTypeVersion, 2); //Doc Type Version
27    Ebml_SerializeUnsigned(glob, DocTypeReadVersion, 2); //Doc Type Read Version
28    Ebml_EndSubElement(glob, &start);
29}
30
31void writeSimpleBlock(EbmlGlobal *glob, unsigned char trackNumber, short timeCode,
32                      int isKeyframe, unsigned char lacingFlag, int discardable,
33                      unsigned char *data, unsigned long dataLength)
34{
35    Ebml_WriteID(glob, SimpleBlock);
36    unsigned long blockLength = 4 + dataLength;
37    blockLength |= 0x10000000; //TODO check length < 0x0FFFFFFFF
38    Ebml_Serialize(glob, &blockLength, 4);
39    trackNumber |= 0x80;  //TODO check track nubmer < 128
40    Ebml_Write(glob, &trackNumber, 1);
41    //Ebml_WriteSigned16(glob, timeCode,2); //this is 3 bytes
42    Ebml_Serialize(glob, &timeCode, 2);
43    unsigned char flags = 0x00 | (isKeyframe ? 0x80 : 0x00) | (lacingFlag << 1) | discardable;
44    Ebml_Write(glob, &flags, 1);
45    Ebml_Write(glob, data, dataLength);
46}
47
48static UInt64 generateTrackID(unsigned int trackNumber)
49{
50    UInt64 t = time(NULL) * trackNumber;
51    UInt64 r = rand();
52    r = r << 32;
53    r +=  rand();
54    UInt64 rval = t ^ r;
55    return rval;
56}
57
58void writeVideoTrack(EbmlGlobal *glob, unsigned int trackNumber, int flagLacing,
59                     char *codecId, unsigned int pixelWidth, unsigned int pixelHeight,
60                     double frameRate)
61{
62    EbmlLoc start;
63    Ebml_StartSubElement(glob, &start, TrackEntry);
64    Ebml_SerializeUnsigned(glob, TrackNumber, trackNumber);
65    UInt64 trackID = generateTrackID(trackNumber);
66    Ebml_SerializeUnsigned(glob, TrackUID, trackID);
67    Ebml_SerializeString(glob, CodecName, "VP8");  //TODO shouldn't be fixed
68
69    Ebml_SerializeUnsigned(glob, TrackType, 1); //video is always 1
70    Ebml_SerializeString(glob, CodecID, codecId);
71    {
72        EbmlLoc videoStart;
73        Ebml_StartSubElement(glob, &videoStart, Video);
74        Ebml_SerializeUnsigned(glob, PixelWidth, pixelWidth);
75        Ebml_SerializeUnsigned(glob, PixelHeight, pixelHeight);
76        Ebml_SerializeFloat(glob, FrameRate, frameRate);
77        Ebml_EndSubElement(glob, &videoStart); //Video
78    }
79    Ebml_EndSubElement(glob, &start); //Track Entry
80}
81void writeAudioTrack(EbmlGlobal *glob, unsigned int trackNumber, int flagLacing,
82                     char *codecId, double samplingFrequency, unsigned int channels,
83                     unsigned char *private, unsigned long privateSize)
84{
85    EbmlLoc start;
86    Ebml_StartSubElement(glob, &start, TrackEntry);
87    Ebml_SerializeUnsigned(glob, TrackNumber, trackNumber);
88    UInt64 trackID = generateTrackID(trackNumber);
89    Ebml_SerializeUnsigned(glob, TrackUID, trackID);
90    Ebml_SerializeUnsigned(glob, TrackType, 2); //audio is always 2
91    //I am using defaults for thesed required fields
92    /*  Ebml_SerializeUnsigned(glob, FlagEnabled, 1);
93        Ebml_SerializeUnsigned(glob, FlagDefault, 1);
94        Ebml_SerializeUnsigned(glob, FlagForced, 1);
95        Ebml_SerializeUnsigned(glob, FlagLacing, flagLacing);*/
96    Ebml_SerializeString(glob, CodecID, codecId);
97    Ebml_SerializeData(glob, CodecPrivate, private, privateSize);
98
99    Ebml_SerializeString(glob, CodecName, "VORBIS");  //fixed for now
100    {
101        EbmlLoc AudioStart;
102        Ebml_StartSubElement(glob, &AudioStart, Audio);
103        Ebml_SerializeFloat(glob, SamplingFrequency, samplingFrequency);
104        Ebml_SerializeUnsigned(glob, Channels, channels);
105        Ebml_EndSubElement(glob, &AudioStart);
106    }
107    Ebml_EndSubElement(glob, &start);
108}
109void writeSegmentInformation(EbmlGlobal *ebml, EbmlLoc* startInfo, unsigned long timeCodeScale, double duration)
110{
111    Ebml_StartSubElement(ebml, startInfo, Info);
112    Ebml_SerializeUnsigned(ebml, TimecodeScale, timeCodeScale);
113    Ebml_SerializeFloat(ebml, Segment_Duration, duration * 1000.0); //Currently fixed to using milliseconds
114    Ebml_SerializeString(ebml, 0x4D80, "QTmuxingAppLibWebM-0.0.1");
115    Ebml_SerializeString(ebml, 0x5741, "QTwritingAppLibWebM-0.0.1");
116    Ebml_EndSubElement(ebml, startInfo);
117}
118
119/*
120void Mkv_InitializeSegment(Ebml& ebml_out, EbmlLoc& ebmlLoc)
121{
122    Ebml_StartSubElement(ebml_out, ebmlLoc, 0x18538067);
123}
124
125void Mkv_InitializeSeek(Ebml& ebml_out, EbmlLoc& ebmlLoc)
126{
127    Ebml_StartSubElement(ebml_out, ebmlLoc, 0x114d9b74);
128}
129void Mkv_WriteSeekInformation(Ebml& ebml_out, SeekStruct& seekInformation)
130{
131    EbmlLoc ebmlLoc;
132    Ebml_StartSubElement(ebml_out, ebmlLoc, 0x4dbb);
133    Ebml_SerializeString(ebml_out, 0x53ab, seekInformation.SeekID);
134    Ebml_SerializeUnsigned(ebml_out, 0x53ac, seekInformation.SeekPosition);
135    Ebml_EndSubElement(ebml_out, ebmlLoc);
136}
137
138void Mkv_WriteSegmentInformation(Ebml& ebml_out, SegmentInformationStruct& segmentInformation)
139{
140    Ebml_SerializeUnsigned(ebml_out, 0x73a4, segmentInformation.segmentUID);
141    if (segmentInformation.filename != 0)
142        Ebml_SerializeString(ebml_out, 0x7384, segmentInformation.filename);
143    Ebml_SerializeUnsigned(ebml_out, 0x2AD7B1, segmentInformation.TimecodeScale);
144    Ebml_SerializeUnsigned(ebml_out, 0x4489, segmentInformation.Duration);
145    //TODO date
146    Ebml_SerializeWString(ebml_out, 0x4D80, L"MKVMUX");
147    Ebml_SerializeWString(ebml_out, 0x5741, segmentInformation.WritingApp);
148}
149
150void Mkv_InitializeTrack(Ebml& ebml_out, EbmlLoc& ebmlLoc)
151{
152    Ebml_StartSubElement(ebml_out, ebmlLoc, 0x1654AE6B);
153}
154
155static void Mkv_WriteGenericTrackData(Ebml& ebml_out, TrackStruct& track)
156{
157    Ebml_SerializeUnsigned(ebml_out, 0xD7, track.TrackNumber);
158    Ebml_SerializeUnsigned(ebml_out, 0x73C5, track.TrackUID);
159    Ebml_SerializeUnsigned(ebml_out, 0x83, track.TrackType);
160    Ebml_SerializeUnsigned(ebml_out, 0xB9, track.FlagEnabled ? 1 :0);
161    Ebml_SerializeUnsigned(ebml_out, 0x88, track.FlagDefault ? 1 :0);
162    Ebml_SerializeUnsigned(ebml_out, 0x55AA, track.FlagForced ? 1 :0);
163    if (track.Language != 0)
164        Ebml_SerializeString(ebml_out, 0x22B59C, track.Language);
165    if (track.CodecID != 0)
166        Ebml_SerializeString(ebml_out, 0x86, track.CodecID);
167    if (track.CodecPrivate != 0)
168        Ebml_SerializeData(ebml_out, 0x63A2, track.CodecPrivate, track.CodecPrivateLength);
169    if (track.CodecName != 0)
170        Ebml_SerializeWString(ebml_out, 0x258688, track.CodecName);
171}
172
173void Mkv_WriteVideoTrack(Ebml& ebml_out, TrackStruct & track, VideoTrackStruct& video)
174{
175    EbmlLoc trackHeadLoc, videoHeadLoc;
176    Ebml_StartSubElement(ebml_out, trackHeadLoc, 0xAE);  //start Track
177    Mkv_WriteGenericTrackData(ebml_out, track);
178    Ebml_StartSubElement(ebml_out, videoHeadLoc, 0xE0);  //start Video
179    Ebml_SerializeUnsigned(ebml_out, 0x9A, video.FlagInterlaced ? 1 :0);
180    Ebml_SerializeUnsigned(ebml_out, 0xB0, video.PixelWidth);
181    Ebml_SerializeUnsigned(ebml_out, 0xBA, video.PixelHeight);
182    Ebml_SerializeUnsigned(ebml_out, 0x54B0, video.PixelDisplayWidth);
183    Ebml_SerializeUnsigned(ebml_out, 0x54BA, video.PixelDisplayHeight);
184    Ebml_SerializeUnsigned(ebml_out, 0x54B2, video.displayUnit);
185    Ebml_SerializeFloat(ebml_out, 0x2383E3, video.FrameRate);
186    Ebml_EndSubElement(ebml_out, videoHeadLoc);
187    Ebml_EndSubElement(ebml_out, trackHeadLoc);
188
189}
190
191void Mkv_WriteAudioTrack(Ebml& ebml_out, TrackStruct & track, AudioTrackStruct& video)
192{
193    EbmlLoc trackHeadLoc, audioHeadLoc;
194    Ebml_StartSubElement(ebml_out, trackHeadLoc, 0xAE);
195    Mkv_WriteGenericTrackData(ebml_out, track);
196    Ebml_StartSubElement(ebml_out, audioHeadLoc, 0xE0);  //start Audio
197    Ebml_SerializeFloat(ebml_out, 0xB5, video.SamplingFrequency);
198    Ebml_SerializeUnsigned(ebml_out, 0x9F, video.Channels);
199    Ebml_SerializeUnsigned(ebml_out, 0x6264, video.BitDepth);
200    Ebml_EndSubElement(ebml_out, audioHeadLoc); // end audio
201    Ebml_EndSubElement(ebml_out, trackHeadLoc);
202}
203
204void Mkv_WriteEbmlClusterHead(Ebml& ebml_out,  EbmlLoc& ebmlLoc, ClusterHeadStruct & clusterHead)
205{
206    Ebml_StartSubElement(ebml_out, ebmlLoc, 0x1F43B675);
207    Ebml_SerializeUnsigned(ebml_out, 0x6264, clusterHead.TimeCode);
208}
209
210void Mkv_WriteSimpleBlockHead(Ebml& ebml_out,  EbmlLoc& ebmlLoc, SimpleBlockStruct& block)
211{
212    Ebml_StartSubElement(ebml_out, ebmlLoc, 0xA3);
213    Ebml_Write1UInt(ebml_out, block.TrackNumber);
214    Ebml_WriteSigned16(ebml_out,block.TimeCode);
215    unsigned char flags = 0x00 | (block.iskey ? 0x80:0x00) | (block.lacing << 1) | block.discardable;
216    Ebml_Write1UInt(ebml_out, flags);  //TODO this may be the wrong function
217    Ebml_Serialize(ebml_out, block.data, block.dataLength);
218    Ebml_EndSubElement(ebml_out,ebmlLoc);
219}
220*/
221