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general:audio_encoders [2010/04/16 22:38]
j.m
general:audio_encoders [2012/11/11 08:51] (current)
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 It produces MPEG-1 Layer 3 ([[Glossary#​MP3|MP3]]) audio streams. Requires //​libmp3lame.so//,​ provided by the liblame0 package. It produces MPEG-1 Layer 3 ([[Glossary#​MP3|MP3]]) audio streams. Requires //​libmp3lame.so//,​ provided by the liblame0 package.
  
-The source code of this codec is from the LAME package, released under the GPL license, see [[http://www.mp3dev.org/​|http://​www.mp3dev.org/]]. It seems that there are some patent issues that prevent the package to be included into the Debian distribution. See a discussion about including LAME into Debian at [[http://​www.debian.org/​devel/​wnpp/​unable-to-package|http://​www.debian.org/​devel/​wnpp/​unable-to-package]].+The source code of this codec is from the LAME package, released under the GPL license, see [[http://lame.sourceforge.net/]]. It seems that there are some patent issues that prevent the package to be included into the Debian distribution. See a discussion about including LAME into Debian at [[http://​www.debian.org/​devel/​wnpp/​unable-to-package|http://​www.debian.org/​devel/​wnpp/​unable-to-package]].
  
 Supported modes: Mono, Stereo and [[Glossary#​Joint Stereo|Joint Stereo]]. Supported rates: 48-384 kb/s [[Glossary#​CBR|CBR]],​ [[Glossary#​ABR|ABR]] and Extreme (aggressive [[Glossary#​VBR|VBR]]). Supported modes: Mono, Stereo and [[Glossary#​Joint Stereo|Joint Stereo]]. Supported rates: 48-384 kb/s [[Glossary#​CBR|CBR]],​ [[Glossary#​ABR|ABR]] and Extreme (aggressive [[Glossary#​VBR|VBR]]).
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 ===== libvorbis ===== ===== libvorbis =====
  
-It produces [[Glossary#Ogg Vorbis|Vorbis]] audio. Requires //​libvorbisenc.so.2//,​ provided in the package libvorbisenc2. This audio format was developed as a Free Software replacement for MP3, where some patent issues persist. Sound quality is comparably better than MP3. The support from players is less ubiquitous, but increasing.+It produces [[Glossary#​Vorbis|Vorbis]] audio. Requires //​libvorbisenc.so.2//,​ provided in the package libvorbisenc2. This audio format was developed as a Free Software replacement for MP3, where some patent issues persist. Sound quality is comparably better than MP3. The support from players is less ubiquitous, but increasing.
  
 Supported modes: Stereo and [[Glossary#​Joint Stereo|Joint Stereo]]. Supported rates: 48-384 kbits. Avidemux can use [[Glossary#​CBR|CBR]] mode or [[Glossary#​VBR|VBR]] mode.  Supported modes: Stereo and [[Glossary#​Joint Stereo|Joint Stereo]]. Supported rates: 48-384 kbits. Avidemux can use [[Glossary#​CBR|CBR]] mode or [[Glossary#​VBR|VBR]] mode. 
  
-Don't put Vorbis audio into AVI! It will result in unplayable video, choose OGM as output container instead.+Don't put Vorbis audio into AVI! It will result in unplayable video, choose ​Matroska or OGM as output container instead.
  
 ===== FAAC ===== ===== FAAC =====
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 It produces [[Glossary#​AAC|AAC]] audio files. This type of audio is not recommended under any circumstances for use with video files (and containers) other than specifically and literally the MP4 container. In the case of the MP4 container, AAC is the best choice you can have, since the only other option is MP3 audio. AAC audio for video files (even MP4 videos) is still fairly poorly supported and often causes players to crash on certain platforms. ​ It produces [[Glossary#​AAC|AAC]] audio files. This type of audio is not recommended under any circumstances for use with video files (and containers) other than specifically and literally the MP4 container. In the case of the MP4 container, AAC is the best choice you can have, since the only other option is MP3 audio. AAC audio for video files (even MP4 videos) is still fairly poorly supported and often causes players to crash on certain platforms. ​
  
-AAC audio supposedly the best available accoustic quality at levels lower than or equal to 96 kb/s while maintaining the smallest file size possible. At levels greater than 96 kb/s AAC files (equivalent to 128 kb/s in Ogg Vorbis), Vorbis acoustic quality is notably better while producing smaller files. ​+AAC audio supposedly the best available accoustic quality at levels lower than or equal to 96(nbsp)kb/s while maintaining the smallest file size possible. At levels greater than 96(nbsp)kb/s AAC files (equivalent to 128(nbsp)kb/s in Ogg Vorbis), Vorbis acoustic quality is notably better while producing smaller files. ​
  
-Essentially,​ in the case of very low level quality on your audio, AAC appears to test as preferable. If you like the audio to sound equivalent to 128 kb/s Ogg Vorbis (which is equivalent to ~160-192 kb/s MP3 files), then use AAC at around 96 kb/s. AAC will give you the best sound for the smallest file at lower quality. If you want higher quality at the smallest file size, the next choice is Vorbis at levels greater than 128 kb/s.+Essentially,​ in the case of very low level quality on your audio, AAC appears to test as preferable. If you like the audio to sound equivalent to 128(nbsp)kb/s Ogg Vorbis (which is equivalent to ~160-192(nbsp)kb/s MP3 files), then use AAC at around 96(nbsp)kb/s. AAC will give you the best sound for the smallest file at lower quality. If you want higher quality at the smallest file size, the next choice is Vorbis at levels greater than 128(nbsp)kb/s.
  
 Requires //​libfaac.so.0//​ and //​libfaad.so.0//​ (encoder and decoder), provided by the libfaac0 and libfaad2-0 packages. The site is [[http://​www.audiocoding.com/​|http://​www.audiocoding.com/​]]. Source code is available under the GPL or LGPL license so it is Free Software, but some patent issues exist on this audio format. Requires //​libfaac.so.0//​ and //​libfaad.so.0//​ (encoder and decoder), provided by the libfaac0 and libfaad2-0 packages. The site is [[http://​www.audiocoding.com/​|http://​www.audiocoding.com/​]]. Source code is available under the GPL or LGPL license so it is Free Software, but some patent issues exist on this audio format.
  
-Supported modes: Stereo and [[Glossary#​Joint Stereo|Joint Stereo]]. Supported rates: 48-384 ​kbits. [[Glossary#​CBR|CBR]].+Supported modes: Stereo and [[Glossary#​Joint Stereo|Joint Stereo]]. Supported rates: 48-384(nbsp)kb/s. [[Glossary#​CBR|CBR]].
  
 ===== FFmpeg MP2 ===== ===== FFmpeg MP2 =====
  
-It produces MPEG-1 layer 2 ([[Glossary#​mp2|MP2]]) files. The support is compiled-in using the //​libavcodec//​ library. The source code of this codec is from the [[http://​ffmpeg.sourceforge.net/|FFmpeg project]], licensed under the LGPL license. Some patent issues concern this software, as other MPEG related software. See [[http://​ffmpeg.sourceforge.net/​legal.php|http://​ffmpeg.sourceforge.net/legal.php]].+It produces MPEG-1 layer 2 ([[Glossary#​MP2|MP2]]) files. The support is compiled-in using the //​libavcodec//​ library. The source code of this codec library ​is from the [[http://​ffmpeg.org/|FFmpeg project]], licensed under the LGPL license. Some patent issues concern this software, as other MPEG related software. See [[http://​ffmpeg.org/legal.html]].
  
-Most FFmpeg codecs were developped from scratch to ensure best performance and high code reusability. Supported modes: Stereo and [[Glossary#​Joint Stereo|Joint Stereo]]. Supported rates: 48-384 kb/s. [[Glossary#​CBR|CBR]] ​Only?+Most FFmpeg codecs were developped from scratch to ensure best performance and high code reusability. Supported modes: Stereo and [[Glossary#​Joint Stereo|Joint Stereo]]. Supported rates: 48-384(nbsp)kb/s. [[Glossary#​CBR|CBR]] ​only?
  
 ===== FFmpeg AC3 ===== ===== FFmpeg AC3 =====
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 ===== TwoLAME ===== ===== TwoLAME =====
  
-It produces MPEG-1 layer 2 ([[Glossary#​mp2|MP2]]) files. The support is statically compiled-in. Due to patent issues surrounding the layer 3 encoder and the ability of most MPEG audio players to play layer 2 files, tooLAME makes a very good drop-in replacement for LAME or other layer 3 encoders under most circumstances. It is a good choice for VCD/SVCD and even DVD audio track.+It produces MPEG-1 layer 2 ([[Glossary#​MP2|MP2]]) files. The support is statically compiled-in. Due to patent issues surrounding the layer 3 encoder and the ability of most MPEG audio players to play layer 2 files, tooLAME makes a very good drop-in replacement for LAME or other layer 3 encoders under most circumstances. It is a good choice for VCD/SVCD and even DVD audio track.
  
 Supported modes: Stereo and [[Glossary#​Joint Stereo|Joint Stereo]]. Supported rates: 48-384 kb/s [[Glossary#​CBR|CBR]]. Supported modes: Stereo and [[Glossary#​Joint Stereo|Joint Stereo]]. Supported rates: 48-384 kb/s [[Glossary#​CBR|CBR]].
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 ===== WAV LPCM ===== ===== WAV LPCM =====
  
-Linear Pulse Code Modulation (or LPCM) is a format that is a popular choice in music production. It can have up to 8 channels of audio at 48 kHz or 96 kHz sampling frequency and 16, 20 or 24 bits per sample. It has a maximum bit rate of 6.144 MB/s. The format, without compressing the sound data, simultaneously samples and captures analog signals and transforms them into digital signals.+Linear Pulse Code Modulation (or LPCM) is a format that is a popular choice in music production. It can have up to 8 channels of audio at 48(nbsp)kHz or 96(nbsp)kHz sampling frequency and 16, 20 or 24 bits per sample. It has a maximum bit rate of 6.144(nbsp)MB/s. The format, without compressing the sound data, simultaneously samples and captures analog signals and transforms them into digital signals.
  
-It's generally limited to use with MPEG files. Using LPCM on an MPEG will allow lossless audio preservation in an uncompressed form, at the cost of lots of space. Use LPCM if the video already has LPCM for its current audio until you want to transcode the audio to some form of lossy audio (like [[Glossary#Ogg Vorbis|Vorbis]],​ [[Glossary#​AAC|AAC]] or [[Glossary#​MP3|MP3]]). ​+It's generally limited to use with MPEG files. Using LPCM on an MPEG will allow lossless audio preservation in an uncompressed form, at the cost of lots of space. Use LPCM if the video already has LPCM for its current audio until you want to transcode the audio to some form of lossy audio (like [[Glossary#​Vorbis|Vorbis]],​ [[Glossary#​AAC|AAC]] or [[Glossary#​MP3|MP3]]). ​
  
general/audio_encoders.txt ยท Last modified: 2012/11/11 08:51 (external edit)