media/libtheora/README@6474c204b198 (annotated)
media/libtheora/README
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
| michael@0 | 1 | ------------------------------------------------------------------------- |
| michael@0 | 2 | The Xiph.org Foundation's libtheora 1.2 |
| michael@0 | 3 | ------------------------------------------------------------------------- |
| michael@0 | 4 | |
| michael@0 | 5 | *** What is Theora? |
| michael@0 | 6 | |
| michael@0 | 7 | Theora is Xiph.Org's first publicly released video codec, intended |
| michael@0 | 8 | for use within the Foundation's Ogg multimedia streaming system. |
| michael@0 | 9 | Theora is derived directly from On2's VP3 codec, adds new features |
| michael@0 | 10 | while allow it a longer useful lifetime as an competitive codec. |
| michael@0 | 11 | |
| michael@0 | 12 | The 1.0 release decoder supported all the new features, but the |
| michael@0 | 13 | encoder is nearly identical to the VP3 code. |
| michael@0 | 14 | |
| michael@0 | 15 | The 1.1 release featured a completely rewritten encoder, offering |
| michael@0 | 16 | better performance and compression, and making more complete use |
| michael@0 | 17 | of the format's feature set. |
| michael@0 | 18 | |
| michael@0 | 19 | The 1.2 release features significant additional improvements in |
| michael@0 | 20 | compression and performance. Files produced by newer encoders can |
| michael@0 | 21 | be decoded by earlier releases. |
| michael@0 | 22 | |
| michael@0 | 23 | *** Where is Theora? |
| michael@0 | 24 | |
| michael@0 | 25 | Theora's main site is www.theora.org. Theora and related libraries |
| michael@0 | 26 | can be gotten from www.theora.org or the main Xiph.Org site at |
| michael@0 | 27 | www.xiph.org. Development source is kept in an open subversion |
| michael@0 | 28 | repository, see http://theora.org/svn/ for instructions. |
| michael@0 | 29 | |
| michael@0 | 30 | ------------------------------------------------------------------------- |
| michael@0 | 31 | Getting started with the code |
| michael@0 | 32 | ------------------------------------------------------------------------- |
| michael@0 | 33 | |
| michael@0 | 34 | *** What do I need to build the source? |
| michael@0 | 35 | |
| michael@0 | 36 | Requirements summary: |
| michael@0 | 37 | |
| michael@0 | 38 | For libtheora: |
| michael@0 | 39 | |
| michael@0 | 40 | libogg 1.1 or newer. |
| michael@0 | 41 | |
| michael@0 | 42 | For example encoder: |
| michael@0 | 43 | |
| michael@0 | 44 | as above, |
| michael@0 | 45 | |
| michael@0 | 46 | libvorbis and libvorbisenc 1.0.1 or newer. |
| michael@0 | 47 | (libvorbis 1.3.1 or newer for 5.1 audio) |
| michael@0 | 48 | |
| michael@0 | 49 | For creating a source distribution package: |
| michael@0 | 50 | |
| michael@0 | 51 | as above, |
| michael@0 | 52 | |
| michael@0 | 53 | Doxygen to build the API documentation, |
| michael@0 | 54 | pdflatex and fig2dev to build the format specification |
| michael@0 | 55 | (transfig package in Ubuntu). |
| michael@0 | 56 | |
| michael@0 | 57 | For the player only: |
| michael@0 | 58 | |
| michael@0 | 59 | as above, |
| michael@0 | 60 | |
| michael@0 | 61 | SDL (Simple Direct media Layer) libraries and headers, |
| michael@0 | 62 | OSS audio driver and development headers. |
| michael@0 | 63 | |
| michael@0 | 64 | The provided build system is the GNU automake/autoconf system, and |
| michael@0 | 65 | the main library, libtheora, should already build smoothly on any |
| michael@0 | 66 | system. Failure of libtheora to build on a GNU-enabled system is |
| michael@0 | 67 | considered a bug; please report problems to theora-dev@xiph.org. |
| michael@0 | 68 | |
| michael@0 | 69 | Windows build support is included in the win32 directory. |
| michael@0 | 70 | |
| michael@0 | 71 | Project files for Apple XCode are included in the macosx directory. |
| michael@0 | 72 | |
| michael@0 | 73 | There is also a more limited scons build. |
| michael@0 | 74 | |
| michael@0 | 75 | *** How do I use the sample encoder? |
| michael@0 | 76 | |
| michael@0 | 77 | The sample encoder takes raw video in YUV4MPEG2 format, as used by |
| michael@0 | 78 | lavtools, mjpeg-tools and other packages. The encoder expects audio, |
| michael@0 | 79 | if any, in a separate wave WAV file. Try 'encoder_example -h' for a |
| michael@0 | 80 | complete list of options. |
| michael@0 | 81 | |
| michael@0 | 82 | An easy way to get raw video and audio files is to use MPlayer as an |
| michael@0 | 83 | export utility. The options " -ao pcm -vo yuv4mpeg " will export a |
| michael@0 | 84 | wav file named audiodump.wav and a YUV video file in the correct |
| michael@0 | 85 | format for encoder_example as stream.yuv. Be careful when exporting |
| michael@0 | 86 | video alone; MPlayer may drop frames to 'keep up' with the audio |
| michael@0 | 87 | timer. The example encoder can't properly synchronize input audio and |
| michael@0 | 88 | video file that aren't in sync to begin with. |
| michael@0 | 89 | |
| michael@0 | 90 | The encoder will also take video or audio on stdin if '-' is specified |
| michael@0 | 91 | as the input file name. |
| michael@0 | 92 | |
| michael@0 | 93 | There is also a 'png2theora' example which accepts a set of image |
| michael@0 | 94 | files in that format. |
| michael@0 | 95 | |
| michael@0 | 96 | *** How do I use the sample player? |
| michael@0 | 97 | |
| michael@0 | 98 | The sample player takes an Ogg file on standard in; the file may be |
| michael@0 | 99 | audio alone, video alone or video with audio. |
| michael@0 | 100 | |
| michael@0 | 101 | *** What other tools are available? |
| michael@0 | 102 | |
| michael@0 | 103 | The programs in the examples directory are intended as tutorial source |
| michael@0 | 104 | for developers using the library. As such they sacrifice features and |
| michael@0 | 105 | robustness in the interests of comprehension and should not be |
| michael@0 | 106 | considered serious applications. |
| michael@0 | 107 | |
| michael@0 | 108 | If you're wanting to just use theora, consider the programs linked |
| michael@0 | 109 | from http://www.theora.org/. There is playback support in a number |
| michael@0 | 110 | of common free players, and plugins for major media frameworks. |
| michael@0 | 111 | Jan Gerber's ffmpeg2theora is an excellent encoding front end. |
| michael@0 | 112 | |
| michael@0 | 113 | ------------------------------------------------------------------------- |
| michael@0 | 114 | Troubleshooting the build process |
| michael@0 | 115 | ------------------------------------------------------------------------- |
| michael@0 | 116 | |
| michael@0 | 117 | *** Compile error, such as: |
| michael@0 | 118 | |
| michael@0 | 119 | encoder_internal.h:664: parse error before `ogg_uint16_t' |
| michael@0 | 120 | |
| michael@0 | 121 | This means you have version of libogg prior to 1.1. A *complete* new Ogg |
| michael@0 | 122 | install, libs and headers is needed. |
| michael@0 | 123 | |
| michael@0 | 124 | Also be sure that there aren't multiple copies of Ogg installed in |
| michael@0 | 125 | /usr and /usr/local; an older one might be first on the search path |
| michael@0 | 126 | for libs and headers. |
| michael@0 | 127 | |
| michael@0 | 128 | *** Link error, such as: |
| michael@0 | 129 | |
| michael@0 | 130 | undefined reference to `oggpackB_stream' |
| michael@0 | 131 | |
| michael@0 | 132 | See above; you need libogg 1.1 or later. |
| michael@0 | 133 | |
| michael@0 | 134 | *** Link error, such as: |
| michael@0 | 135 | |
| michael@0 | 136 | undefined reference to `vorbis_granule_time' |
| michael@0 | 137 | |
| michael@0 | 138 | You need libvorbis and libvorbisenc from the 1.0.1 release or later. |
| michael@0 | 139 | |
| michael@0 | 140 | *** Link error, such as: |
| michael@0 | 141 | |
| michael@0 | 142 | /usr/lib/libSDL.a(SDL_esdaudio.lo): In function `ESD_OpenAudio': |
| michael@0 | 143 | SDL_esdaudio.lo(.text+0x25d): undefined reference to `esd_play_stream' |
| michael@0 | 144 | |
| michael@0 | 145 | Be sure to use an SDL that's built to work with OSS. If you use an |
| michael@0 | 146 | SDL that is also built with ESD and/or ALSA support, it will try to |
| michael@0 | 147 | suck in all those extra libraries at link time too. That will only |
| michael@0 | 148 | work if the extra libraries are also installed. |
| michael@0 | 149 | |
| michael@0 | 150 | *** Link warning, such as: |
| michael@0 | 151 | |
| michael@0 | 152 | libtool: link: warning: library `/usr/lib/libogg.la' was moved. |
| michael@0 | 153 | libtool: link: warning: library `/usr/lib/libogg.la' was moved. |
| michael@0 | 154 | |
| michael@0 | 155 | Re-run theora/autogen.sh after an Ogg or Vorbis rebuild/reinstall |
| michael@0 | 156 |
