Per definition: transcription
Transcription (from Latin: trans scribere -> transcribere: to transfer (text)) is one of two things:
- Taking audio and turning it into text
- taking one text and turning it into a text in a different writing style, e.g. Cyrillic to Latin, Japanese (Kanji, Katakana, Hiragana) to Romanji, handwritten script to digital Latin letters.
To transcribe is to make a copy
A transcription is by default a full copy of the original text. If it is a pure transcription, there is no creative element added - a translation would have such an element in some regard.
Making a copy under copyright
Copyright is the exclusive right of the Author to make copies or assign the right to make copies. So by default, transcriptions are copyright infringement.
However, there is fair use or fair dealing. In the US, Fair-use is defined as needing to satisfy the fair use factors more than not. They are defined in 17 U.S.C. § 107:
- the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes;
- the nature of the copyrighted work;
- the amount and substantiality of the portion used in relation to the copyrighted work as a whole; and
- the effect of the use upon the potential market for or value of the copyrighted work.
In general, the second factor more often than not cuts against fair use in works of fiction. Transcription of the whole work also wouldn't necessarily be fair use, as the third factor demands the absolute minimal amount needed to be taken. However, factor 1 - personal non-profit use, especially for research or criticism - can heavily cut for fair use. And factor four, "market impact", of a purely personal file that never enters circulation heavily cuts for fair use. As a result, it might be fair use, if for purely personal use.
Sharing would alter the market impact: the more the file is shared, the more market impact it has - it is a full substitute, so it might be deemed to destroy the market of the original, cutting heavily against fair use.