TEXT TO SPEECH TO RAP SYNTHESIS
Panajis Rantala

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USAGE: python3 espeak.py

1: choose a lyric text file (from list) to be synthesized.
   Before playback inquires if you want to delete the 
   (now useless) .wav files created in synthesis. 
   Resulting concatenated lyric file <song_name>.wav
   is saved in the working directory.

2: Choose a synthesized lyric wav-file (from list) to be mixed with beat.
   Choose a accompanying beat wav-file (from list).
   Program mixes and plays the output, saves the mixed song
   into /songs/<song_name+beat_name>.wav

3: Create phonemedata for lyric text file. No interaction with synthesis,
   just for reference.

NOTE!!!!
Only works with shell based terminals/OS', trivial to change but meh
(Uses ls, rm, aplay)

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EXAMPLE RUN:

python3 espeak.py
1
XTRA

2
XTRA
100low

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ABOUT FILES:

Lyrics are to be in extensionless format. The name is used as the
song name in synthesis. First line specifies BPM (e.g. 100), after
that comes lyrics. One line is treated as a one line in song which should
fit in one bar. Separate rhyming part with underscore "_" from the first part.
Synthesis supports empty lines as one bar of silence (useful when mixing with beat).
NO ERROR HANDLING, REMEMBER TO SPECIFY BPM AS FIRST LINE AND INCLUDE UNDERSCORE IN
EVERY LYRIC LINE!

Synthesized wave-files. Depending on "mbrola"-flag, which specifies the voicebank
used, the wavs are created with 1 channel, 2 bit audio depth, framerate of EITHER 
22050Hz (espeak) or 16000Hz (mbrola). THIS HAS TO CORRESPOND TO THE FRAMERATE OF 
ACCOMPANYING BEAT WAV! Use xxxhigh for espeak voices (mbrola=False), and xxxlow 
for mbrola voices (mbrola=True), where xxx is the bpm (and how my beats are named). 
By default mbrola is True.

Accompanying beat wave-files. Ripped from youtube and converted to .wav. As stated 
above the filename consists of bpm <xxx> and framerate <high> or <low>. For example 
when using the program with default options (mbrola=True), choose a lyricfile first,
and then the beat file with corresponding BPM and low framerate (XTRA -> 100low).
Sources for most beatfiles can be found in /mp3/BEAT REFERENCES.  

Mixed songs (lyrics and beat) are saved in the "songs" directory, and retain the 
wave parameters specified in synthesis. Named with <song_name>+<beat_name>.wav.

Wavs created during synthesis. The program creates a wav-file for every lyric segment
(first part, rhyming part, doubled rhyme, trimmed wavs). The working directory is 
populated by these and it can get quite messy during runtime. The program automatically
deletes these temporary wavs after execution. The wavs are named with 
<song_name>-<line_number>-<[0 or 1](for first/rhymepart)>[-DELAY,DOUBLED,-TRIM-,etc].wav
Padding for samples are named with <silence>-<line_number>. All these can be ignored.

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OPTIONS:

(Default values in code, toggleable via the action chooser during runtime.)

OPTION	       DEFAULT   DESCRIPTION
'mbrola'       True      Defines the voice used in synthesis. If false -> espeak 
'augment'      False     Augments the phonemes by accenting first syllable. not good
'double'       True      Creates double tracking for rhymepart.
'constant_WPM' True      Instead of using per line calculated WPMs, uses a mean
			 with some tweaking.
'trim'         True	 espeak leaves some silence in the beginning and end of 
			 synthesized files. This removes it to ensure wpm 
			 calculations work.
'start_silence'False     Instead of adding silence in between the first and rhyming
			 part, this flag creates it in the beginning of the line.
			 Doesn't sound good as is but could be incorporated with
			 some testing to the wpm calculations.  
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DIRECTORIES:

lyrics: Put here all your lyricfiles (text)
beats:  Put here all your instrumental beats (wav)
songs:  Here the program will output mixed songs (wav)
	(Populated automatically, don't put anything here)
mp3:    Not used for anything. Houses the mp3-versions of beats.