Tuesday, 28 August 2018

Similarity test algorithm

A plagiarism checker algorithm has been developed to calculate an index that is proportional with the melodic similarity between samples. It considers melody, rhythm, harmony and some other factors as well. Some of these factors are calculated in a sophisticated way to result a more reasonable value.

Melodyc factor is considering same pitch, different pitch (decreasing effect), closely timed notes, intervals, repetitions, ...
Rhythm factor is considering note locations and for some extent rests as well.
Harmony factor is considering chord changes weighing by how usual/unusual they are.
The "others" factor is considering tempo, location (section, phrase, bar), similarity of instrumentation. More details only for those who interested.

The test is still under fine tuning.
Preliminary test results below, so the results may change a bit up or down. Keep in mind the proposed limit is around 8.0, that has to be handled carefully. Between 7.0 and 9.0 there is a "gray" range, but out of this the case is more or less black or white. 

1) Stay With Me vs. I Won't Back Down
Similarity index: 11,96

Melody: 9,23
Rhythm: 1,14
Harmony: 1,02
Others: 1,11

Clear case.

2) Blurred Lines vs. Got To Give It Up

2a) Blurred Lines vs. Got To Give It Up - "signature phrase"
Similarity index: 2,83

Melody: 2,8
Rhythm: 1,02
Harmony: 0,92
Others: 1,08

This result is maximized by triming off the non-matching notes. Without the trimming the entire phrase would result a negative value due to the too many different notes.

2b) Blurred Lines vs. Got To Give It Up - "hook"
Similarity index: 3,91
Melody: 3,45
Rhythm: 1,09
Harmony: 1,06
Others: 0,98

By far the highest result in the case. Only one perfect match, plus three close ones.

2c) Blurred Lines vs. Got To Give It Up - bass
Similarity index: 1,48

Melody: 1,23
Rhythm: 1,01
Harmony: 0,95
Others: 1,25

This result too is maximized by triming off the non-matching notes. Without the trimming the entire phrase would result a negative value due to the too many different notes.

2d) Blurred Lines vs. Got To Give It Up - 5 to 1 bass motif
Similarity index: 1,30

Melody: 1,72
Rhythm: 0,80
Harmony: 0,79
Others: 1,19

2e) Blurred Lines vs. Got To Give It Up - hey-hey-hey
Similarity index: 0,45

Melody: 0,70
Rhythm: 0,80
Harmony: 0,79
Others: 1,02

The lowest index the trimming couldnot save it either. It was also pointed out as a similar motif by musicologists and later testified as being substantially similar (with all other points).

Blurred Lines vs. Got To Give It Up - "keep on dancin"
Similarity index: 0,93

Melody: 1,10
Rhythm: 1,00
Harmony: 0,91
Others: 0,93

Summary of the six Blurred Lines vs Got To Give It Up samples:

c to f are ranging from 0,55 to 1,43. We could just say "no comment", but it cries out
for a comment. These are ridicoulusly low values to label as substantially similar
or even just similar. Gayes-party expert in her testimony claimed each
of these being substantially similar - in the musicologic meaning of the word.

Also note that none of these patterns occure simultainously or subsequently.
Now think it over what percentage of randomly chosen (pop) songs contain
an at least 4,17 and a 2,76 strong melodic coincidence. See the blog article Accidental similarity.

3) Blurred Lines vs Another One Bites The Dust
Similarity index: 3,46
It's just a melismatic motif with nine (!) consecutive matching notes, that are following a commonplace pattern. The algorhythm effectively compensates the repeated commonplace motifs.

Melody: 4,6
Rhythm: 1,11
Harmony: 0,8
Others: 0,9

4) Sweet Child Of Mine vs. Unpublished Critics
Similarity index: 5,72

Melody: 4,1
Rhythm: 1,03
Harmony: 1,1
Others: 1,28

This refers only to the verse melodies. Similarly to 2a) the result would be much lower (a negative value) if the comparation would consider the entire phrase. For getting a higher result the non-matching motes were trimmed down from the melodic comparison. In this case there were other similar details as well.

5) Creep vs. Air That I Breathe
Similarity index: 9,14

Melody: 7,01
Rhythm: 1,13
Harmony: 1,15
Others: 1,00

The compared pattern in Creep is the falsetto sung melody after the "solo".

6) Get Free vs. Creep
Similarity index: 9,64 (depends on!)

Note that in this case the complaining melodies in Creep are different from those that are similar with the Air That I Breathe. The two cases are melody-wise independent from eachother.
The melodies in this case are just partly similar. Some phrases are rather different. The rough placement of the phrases is similar in both songs: starting 2-3 beats before the downbeat of the actual harmonic phrase (where the chords change).
We have two different verses in both songs. Slightly different in Get Free more
different in Creep (phrases 3 and 4). To maximize the matching notes I hade to take the closer variant of the verses which is the first verse in Creep.
The highest result was given by considering phrase 3-4 of verses through phrases 1-2 of chorus. This is a "cheat" in favour of Creep since these phrases are not subsequent with the chorus phrases. Without this cheat the index would not reach the proposed limit at 8.0!

Melody: 8,5
Rhythm: 0,87
Harmony: 1,18
Others: 1,10

7) Photograph vs. Amazing
Highest score is resulted by the first ABB sequence of phrases that shows a similarity index of: 10,90 according to the algorithm. The non-repeated phrases would result a lower value.

Melody: 9.03
Rhythm: 1.06
Harmony: 1.09
Others: 1.04

8) Come As You Are vs. Eighties
Similarity index: 12,64

Melody: 9,13
Rhythm: 1,03
Harmony: 1,08
Others: 1,24

13,81 considering the repetitions.

Clear case? Not quite! Just to mess things up:

Eighties (1985) vs. Life Goes On (1982)
Similarity index: 12,06 or 16,88 considering the repetitions.

Come As You Are vs. Life Goes On
Similarity index: 10,52
11,19 considering the repetitions.

Love Is A Wonderful Thing (Isley Brothers) vs. Da Doo Ron Ron
Similarity index: 7,40
Under the limit.

Melody: 6,62
Rhythm: 1,06 The shuffle beat difference is considered in the "others" factor: 0,9.
Harmony: 1,02
Others: 1,04

Love Is A Wonderful Thing (Michael Bolton)
Love Is A Wonderful Thing (IsleyBrothers)
Similarity index: 6,78

Melody: 3,90
Rhythm: 1,14
Harmony: 0,98
Others: 1,56 The four identic words alone contribute with a 1,2 gain.

This best result was by choosing the once-occuring title phrase variant in Bolton's song, next to the sax solo. The most frequently occuring Bolton variants resulted in an 3,82 index.

Thinking Out Loud vs. Let's Get It On

The bass base loop.
Similarity index: 7,37

This a surprisingly high index for a four note melody. It is considering the looping with a 1,4 "gain". Since it is a commonplace motif even in prior art, it does not matter much.

Melody: 6,30
Rhythm: 1,10 (if the3+5 pattern would not be commonplace this factor would be higher)
Harmony: 1,04
Others: 1,80

TOL verse 1st phrase vs. LGIO chorus 3rd phrase
The opening notes, the title phrase in LGIO is a traditional fanfare motif. The compared fragment is a melismatic motif in LGIO: 3-4 notes only, since the rest is rather different.
Similarity index: 3,46

Melody: 3,85
Rhythm: 0,87
Harmony: 1,07
Others: 0,97

TOL verse 2st phrase vs. LGIO chorus 4rd phrase 
(the 3 5 6 5 3 motif)
Similarity index: 2,81

Melody: 2,9
Rhythm: 1,13
Harmony: 0,93
Others: 0,92

TOL verse with LGIO verse
Very different melodies. There is a two note fragment that is "similar".
Similarity index: 1,52

Melody: 1,49
Rhythm: 0,9
Harmony: 1,06
Others: 1,08

Walk vs. Nem Vagyok Tökéletes
Similarity index: 9,25

Melody: 8,36
Rhythm: 1,03
Harmony: 1,10
Others: 0,98

The "complaining" song is from aHungarian band. This one is an unprobable case of access, so it must be accidental in spite of the index being over the gray range. The calculation considers the repetition. Homekey is the same and the chords as well.

Shape Of You vs. No Scrubs
Similarity index: 5,14

Melody: 5,33
Rhythm: 1,10
Harmony: 0,85
Others: 1,03

There is a similar passage indeed, but the strength of the similarity does not close even the "gray" range. It's above the "usual" level of Marvin Gaye cases tough...
See the Accidental similarity for an example of a melodic factor of 4,8 occuring accidently between two of the three songs chosen randomly.

Thinking Out Loud vs. Forget You
Similarity index:7,11

Rhythm: 1,01
Harmony: 0,96
Others: 0,99

Close one on the low end of the "gray" range. Stronger similarity than that of Shape vs. Scrubs...

Ice Ice Baby vs. Under Pressure
Similarity index: 12,20

Melody: 9,21
Rhythm: 1,15
Harmony: 1,06
Others: 1,08

This one was a case of sampling. The similarity works as if it would be a simple "rip-off".

Firework vs. Always
Similarity index: 7,14

Melody: 7,9
Rhythm: 1,02
Harmony: 1,04
Others: 1,04

Some different notes are saving Fireworks.

Stairway To Heaven vs. Taurus
Similarity index: 4,70

Melody: 3,50
Rhythm: 1,02
Harmony: 1,02
Others: 1,30

It's was a special test as some beats were playing two notes simultainously. Even without the consideration of commonplace motifs the melodic similarity is still under the "limit".
There are certainly many identic and close notes, but the different notes (for example the open B string notes of Taurus and the top notes of Stairway) are holding back the result.
Taurus has a "twin" song called Summer Rain that was recorded roughly in the same months. These two songs share 11 consequtive notes.

Starboy vs. Yooho
Similarity index: 9,39

Melody: 6,3
Rhythm: 1,08
Harmony: 1,05
Others: 1,30

The melodyc similarity itself is not strong enough, but many other factors are amplifying it: BPM, chords, key, instrumentation, location,...
The best result is obtained by comparing the first phrases only.

Wednesday, 15 August 2018

Photograph - Amazing

Ed Sheeran’s hit single Photograph was claimed to be infringing the Amazing by Matt Cardle.
The original complaint document are available here.
The news reported about "verbatim, note-for-note copying".

There were at least two independent musicologists both of whom argued that this case is obviously an infringement.
Opinion 1
Opinion 2
Opinion 3
These opinions mention the 39 coinciding notes out of 64 total notes - taken from the original complaint. This ratio was a key point for both of the independent experts judging this case to be an infringement indeed.

My remark on this:
The two independent musicologists did not point out that the compared 16 bars consist of 8 phrases, most of which are close variants. These variants have two major types A and B. The sequence of these variants: ABBB ABBB.

Now let's think of this:
There are huge amount of songs with the same progression of four chords repeated long and where these chord are based on the same simple bassline of four looped notes. If we compare only these bass notes, then we can obtain another 16 bar or even much longer sections where  (most of) the notes coincide. We know that this is a cheat and will not convince us about song level substantial similarity. Those four bass notes can be considered as one cycle, then consider the repetitions for a certain extent (weight).

Considering the repetition the case still shows a strong similarity. See results in the "similarity test algoritm".

Wednesday, 8 August 2018

Similar songs

Since the infamous Blurred Lines case songwriters should be more aware of avoiding plagiarism. Still you can find that a big percentage of songs that are melodically resembling to other prior song. The sound-alike copying is widely and willfully used in the lower leagues of the pop-business, but also in the top songs.

Back then the Blurred Lines verdict (and recently Let's Get It On too) was supported by a couple of quotes by pop musicians or others feeling similarity between two songs. 

I'm having similar experiences all the time, quite a few. Probably more than others. Hereby I list 25 recent plus some older songs that show melodic (or sound) similarity with an other prior song. A part of these are commonly known, a big part of them are my own findings. 
Once someone points out the similarity, lay people are expected to recognise it too and say "wow, indeed!". Even small similarities or 4-5 coinciding notes are sufficient to creat an impression of similarity, even for first listen. Remember Stairway?
In plagiarism trials lay people jurors may also vote for "yes, these are similar indeed" unless they are not properly instructed. The majority of the findings in the list below are not close enough to take too seriously.

Clean Bandit: Symphony
Pharrell Williams, Robin Thicke: Blurred Lines

Not a close one at all, but compared to the "substantial similarity" that was shown in the Blurred Lines vs Got To Give It Up trial, it is definitely in a higher class. The function of these passages also coincide.

1 . 2 . 3 . 4 . 1 . 2 . 3
1 2 3 5 3 5 6 1 2   2 1   :  Symphony
  3 3 2 3 5 6 1 1   1     : Blurred Lines
    *   * * * *           : matching notes
  5 5 5 5 6 1 2     1 5 6 : GTGIU

see also Sweet Lullaby

Meghan Trainor: All About That Bass
Pharell Williams, Robin Thicke: Blurred Lines

A double arch motif. Many matching notes, but it was not instant finding. 

Enrique Iglesias: Duele El Corazon
A. L. Webber: Then We Are Decided

1 . 2 . 3 . 4 . 1 . 2 . 3 . 4 . 1 . 2 . 3 . 4
            1111 31         432 1 4 4
            111 3 1         433 2 3

Avicii: I'm Addicted To You
Beatles: While My Guitar Gently Weeps
Melody plus the combination of chord and descending inner line. Harmony vocals are also reminiscent of other Beatles song. Instantly recognised.

David Guetta ft. Zara Larsson: This One's For You
Queen:Who Wants To Live Forever
This is a case of parallelling melodies with almost identical special rhythm. It was another instant finding.

. 1 . 2 . 3 . 4 . 1 . 2 . 3 . 4 . 1 . 2 . 3 . 4 . 1 .  
 11      12      223             33      34#     445
 11      15      556             11      17      771'

Katy Perry: Fireworks
Erasure: Always
Regarding the length and speciality (rhythm and wide melodic leaps) this one is a relatively clear case of plagiarism.

. 1 . 2 . 3 . 4 . 1 . 2 . 3 . 4 . 1 . 2 . 3 . 4 .
5,1             5,2           1 2 3     1     6,

Sam Smith: Stay With Me
Tom Petty: It Won't Back Down
A well known, heavily discussed case.
The long melody and the very special rhythm makes it an easy to judge case.

Katy Perry: Chained To The Rhythm
Beatles: All You Need Is Love
The outro vocal of CTTR resonates with that of the AYNIL intro hook. Very far from plagiarism, but easy to recognise.

Pharell Williams, Robin Thicke: Blurred Lines
Double Trouble ft Rebel MC - Just Keep Rockin'
sound alike

"copyed elements": 
backbeat chords on "Rhodes", 
"Hoo" vocals, 
vocal percussion rhythm in JKR = cowbell rhythm in BL.
Plus: three gents (performers) and a biking lady on the video :).

Adele: Rolling In The Deep (opening melody)
Metallica: Orion (guitar solo fragment)
Five notes only.

Portugal.The Man: Feel It Still
Marvellets: Please Mr Postman
Obvious case. Even the Wikipedia article mentions this.

Major Lazer/Justin Bieber/MO: Cold Water
Eric Clapton: I Shot The Sheriff
The hooks are very close. Instantly found.

Justin Bieber: Love Yourself
Bee Gees: How Deep Is Your Love
That was another instant finding, but not plagiarism.

Jason Derulo: Swalla
Art Company: Susanna (I'm Crazy Loving You)
Mainly the rhythm phrasing (first two phrases). This was an instant finding too.

Willy William: Ego
Antonio Vivaldi: Concerto for two violins in A minor.
Just a short motif that is repeated:
1 2 3 4 1 : beats
3 3 3 212 :

Selena Gomez, Marshmellow: Wolves 
Police: Every Breath You Take
The hooks are similar and sound-alike. Instant finding.

Pink: U + Ur Hand
Marvin Gaye: Got To Give It Up
Fragmentary bass and cowbell.
The hook is much more reminscent of Papa Was A Rolling Stone (The Temptations).

  1 2 3 4 1 2 3 4 1 
#71         33 7  1 : PWARS
 11         33 7 11 : UUR

The chorus also resebles to It's My Life (Bon Jovi)

Lady Gaga - Born This Way
Madonna: Express Yourself
Well discussed case.

Burak Yeter: Tuesday
Jean Michel Jarre: Equinoxe
The intros sound similar.


Jonas Blue (Tracy Chapman) - Fast CarBeatles: Cry Baby Cry
Just a special syncopated rhythm.

Fifth Harmony, Kid Ink: Worth It
Jason Derulo: Talk Dirty
A well known, instantly recogniseable case.

Mike Posner: Cooler Than Me
Katy Perry: I Kissed The Girl
Sound alike.

OneRepublic: Counting Stars
Bloodhound Gang: The Bad Touch
Sound alike.

Ed Sheran: Perfect
Righteous Brothers: Unchained Melody
Far from plagiarism, still the verses are reminiscent.

Ed Sheran: Thinking Out Loud
Cee Lo Green: Forget You
Opening melodies. This one was not an instant finding at all, no wonder no one else (?) noticed it yet. But many notes coincidence.

26) Kwabs: Walk
Zanzibar: Nem Vagyok Tökéletes
The "complaining" work is a Hungarian song from 2001.
The choruses are very similar: eight notes per phrase.
There are three similar consecutive phrases.
On the other hand: these phrases are repeated (with minor changes).
Above points also coincide with the Photograph-Amazing case.
The shape of the melody (3-2-1-7-1) is very common. The access is unprobable.

1 2 3 4 1 2 3 4 1
    333 2 1 1 71  : NVT 
    333 211 17711 : Walk (with slided notes)
    333 2 1 1 7 1 : Walk (without slided notes)

Robin Schulz: Unforgettable
Justin Bieber: Sorry


Older findings by me:

Tom Jones: Sexbomb
Merle Travis: 16 tons.
Third phrase of the chorus

Tom Jones: Delilah 
Consuelo Velazquez: Besame Mucho
Only the third phrases.

Beatles: Things We Said Today
Roy Orbison: Working For A Man
Sound alike.

Mamas And Papas: Dream A Little Dream Of Me
Beatles: Blackbird
Intro pick-up, 9 notes. Difference: shuffle beat / even beat.

Justine Timberlake: Can't Stop The Feeling
Spice Girls: Say youll be there
The bridges are reminiscent.

Whitney Houston: One Moment In Time
Freddie Mercury: There Must Be More To Life Than This

Third phrase of the chorus (Verse in TMBMTL) and chords.
1 . 2 . 3 . 4 . 1 . 2 . 3 . 4
  6 66 7     765    32 1     : TMB
6     787     5 5     321    : OMIT
4       5       1       6    : chords

Jason Crest: Waterloo Road
Queen: Killer Queen

 3     2     1     7     6  
.1 .2 .3 .4 .1 .2 .3 .4 .1 .2 .3 .4
.353  3232  2131  1727  56 12 13 : WR
 3 3  1212  71 1  1727  7666     : KQ
 * *   * *   * *  ****   *  
Except the fourth block only the descending notes are matching

Queen: We Will Rock You
Lee Dorsey: Working In A Coal Mine
The shape of the opening notes are close.

Build Me Up Buttercup
Abba: Waterloo
Paralelling melodies plus the piano motif.

Extreme: Midnight Express
Mike Oldfield: Taurus 3 (esp. "Good Morning Britain" performance)

Steam: Na Na Hey Hey Kiss Him Good Bye
Hans Zimmer: He Is A Pirat

Pirat is in 3/4, NaNa is in 4/4 meter:

4 1 2 3 4 1 2
561 1   123 3 

3 1 2 3 1 2
561 1 123 3

Beatles: Hey Jude
Jean Michel Jarre: Magnetic Fields part 5

parallelling melodies
4 1 2 3 4 1 
5 3    3562 : HJ
8 5    6783 : MF