Changes between Version 8 and Version 9 of Encode/HighQualityAudio
- Timestamp:
- Apr 7, 2013, 5:10:22 PM (14 years ago)
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Encode/HighQualityAudio
v8 v9 8 8 == Generation loss == 9 9 10 Transcoding from a lossy format like (MP3,AAC,Vorbis,Opus,WMA etc.)to the same or different lossy format might degrade the audio quality even if the bitrate stays the same(or higher). This quality degradation might not be audible to you but it might be audible to others.[[BR]]10 Transcoding from a lossy format like MP3,AAC,Vorbis,Opus,WMA etc. to the same or different lossy format might degrade the audio quality even if the bitrate stays the same(or higher). This quality degradation might not be audible to you but it might be audible to others.[[BR]] 11 11 This post on hydrogenaudio.org demonstrates what will happen if you transcode a file 100 times: [[http://www.hydrogenaudio.org/forums/index.php?showtopic=100067]] 12 12 … … 16 16 This can be achieved by specifying 'copy' as the audio codec. 17 17 Example:[[BR]] 18 Transcoding a WebM file with a VP8 video track and Vorbis track to a MKV file with H.264 video track and Vorbis audio track:[[BR]]18 Transcoding a WebM file (with VP8 video/Vorbis audio) to a MKV file (with H.264 video/unaltered Vorbis audio):[[BR]] 19 19 {{{ 20 20 ffmpeg -i someFile.webm -c:a copy -c:v libx264 outFile.mkv … … 46 46 Even though AAC should generally give better quality than MP3 at the same bitrates libmp3lame should give better quality output than libfaac.[[BR]] 47 47 This list is just a general idea and there might be cases where codecs listed to the right might perform better than those listed to the left at certain bitrates. [[BR]] 48 The bestinternal/native encoder available in ffmpeg without any external libraries is eac3/ac3. [[BR]]48 The highest quality internal/native encoder available in ffmpeg without any external libraries is eac3/ac3. [[BR]] 49 49 50 50 Please note it is '''not recommended''' to use 'libvo_aacenc' for AAC encoding.[[BR]] … … 59 59 ||'''WebM'''||Vorbis|| 60 60 ||'''OGG'''||Vorbis,Opus|| 61 Please note that there more container formats available than those listed above.61 Please note that there are more container formats available than those listed above. 62 62 63 63 == Recommended minimum bitrates to use == 64 64 65 Please note that the bitrates listed here assumes the audio is Stereo and>= 44.1Khz. Mono could require less bits.[[BR]]65 Please note that the bitrates listed here assumes the input audio channels is Stereo and the sample rate is >= 44.1Khz. Mono could require less bits.[[BR]] 66 66 67 67 - '''libopus''' Recommended usable range '''>= 64Kbps'''. Compression artifacts start becoming unnoticeable around 96Kbps[[BR]] … … 81 81 ---- 82 82 83 Please note Opus streams are currently not muxable in MKV containers. Only Ogg Containers a t the moment.[[BR]]83 Please note Opus streams are currently not muxable in MKV containers. Only Ogg Containers are supported at the moment. MKV container support is should be available in the future[[BR]] 84 84 When compatibility with hardware players doesn't matter then use libvorbis in a MKV container rather than libfaac when libfdk_aac isn't available[[BR]] 85 When compatibility with hardware players does matter then use libmp3lame or eac3/ac3 in a MP4/MKV container rather than libfaac when libfdk_aac isn't available[[BR]]86 Transparency means the encoded audio sounds indistinguishable from the source file.85 When compatibility with hardware players does matter then use libmp3lame or ac3 in a MP4/MKV container rather than libfaac when libfdk_aac isn't available[[BR]] 86 Transparency means the encoded audio sounds indistinguishable from the audio in the source file.
