Added instructions for audio transcoding #24
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I would suggest running flac with |
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Also it would be pretty nice to expand on multichannel files a bit because certain channel layouts will fail to encode with the current examples. |
FichteFoll
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Sorry it took so long to review this. I started reviewing this months ago but somehow didn't end up finishing it and then it got buried in my open tabs and lack of time, which I'm now trying to catch up on.
Please separate all code blocks from text with a blank line.
For semantic line feeds, it is very rare to not have a line break after a comma and usually only for small enumerations or the likes of "Additionally,", whose proper name I forgot. Some sentences in here have odd line breaks.
| examples for qaac, flac | ||
| As said earlier, only qaac will require configuration, | ||
| and everythig else can simply be extracted wherever you like. | ||
| But, for the ease of use, we suggest adding them to PATH, |
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I'm not on top of the entire guide's contents, but is "adding to PATH" explained anywhere? Or maybe we can add a glossary entry for an all-caps PATH with explanations without having to repeat or reference this all the time?
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| ### Decoding audio with ffmpeg and piping it out | ||
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| Basic ffmpeg usage is very simple—you just need to specify the input file, |
| The command above will decode the source file | ||
| and save a resulting WAV file on your drive. | ||
| You can then use this WAV file to encode a FLAC or AAC file, | ||
| but there is a faster and more convinient way to do that—piping. |
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| but there is a faster and more convinient way to do that—piping. | |
| but there is a faster and more convenient way to do that: piping. |
| any information about the length of the file, | ||
| or that information is incorrect, | ||
| which makes it stop the encoding before the file actually ends. | ||
| With this option FLAC will ignore the header |
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| With this option FLAC will ignore the header | |
| With this option, FLAC will ignore the header |
| and place the whole command after the ffmpeg command, | ||
| like this: | ||
| ``` | ||
| ffmpeg -i "input.dts" -acodec pcm_s24le -f wav -| flac -8 --ignore-chunk-sizes - -o "output.flac" |
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24bit flac is padded to 32 bits per sample, which means 25% of the resulting file contain no information. Encoding dts to wav 24-bit seems reasonable, but at this point we should definitely mention this fallacy with flac. See also #2.
| opusenc --bitrate 160 --vbr --ignorelength "input.wav" "output.opus" | ||
| ``` | ||
| As you may have noticed, | ||
| opusenc CLI uses bitrate control, |
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I don't think there should be a comma here?
| ``` | ||
| As you may have noticed, | ||
| opusenc CLI uses bitrate control, | ||
| insted of some kind constant quality mode, like in qaac. |
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| insted of some kind constant quality mode, like in qaac. | |
| instead of some kind constant quality mode, like in qaac. |
| As you may have noticed, | ||
| opusenc CLI uses bitrate control, | ||
| insted of some kind constant quality mode, like in qaac. | ||
| This doesn't mean it works in constant bitrate mode—[the target bitrate is calibrated against the internal constant quality targets |
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That's a really long link text. Please try to rephrase this.
| so that over a typical music collection, | ||
| something very close to the target bitrate will be achieved][opus_hydrogen]. | ||
| This makes choosing the proper target quality | ||
| a little bit funky—you will have to set different bitrate for stereo and for multichannel files. |
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| a little bit funky—you will have to set different bitrate for stereo and for multichannel files. | |
| a little bit funky. | |
| You will have to set different bitrate for stereo and for multichannel files. |
A period here is fine.
| a little bit funky—you will have to set different bitrate for stereo and for multichannel files. | ||
| As per HydrogenAudio recommendation, | ||
| the recommended bitrate for stereo is 160 kbps, | ||
| while for 5.1 something in the neighbourhood of 320-384 kbps should be OK. |
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| while for 5.1 something in the neighbourhood of 320-384 kbps should be OK. | |
| while for 5.1 something in the range of 320-384 kbps should be OK. |
If the two spaces at the end of the line are intended, use <br> to add a line break instead. Those are resistent to removal of trailing whitespace.
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i can help |
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here #62 |
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Superseded by #62 (which has been merged). |
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I know that @LightArrowsEXE already wrote this, but his instructions are not in line with what was written on the "Preparation and Necessary Software" site (using ffmpeg flac instead of libflac), he repeated a lot of things already written in the aforementioned site, and also added a lot of information that are completely unnecessary, like explaining the difference between lossy and lossless (basic knowledge that is IMO not needed in this guide, plus it's also mentioned in "Preparation and Necessary Software") or comparing file sizes for different flac levels, or explaining what "FLAC" means, lol. I also disagree with some of his statements, which I commented in his pull request #21.