Vision api imageProperties dominant color score meaning

Hi,
we are using vision api for image analysis.
In the image properties, the dominantColor field is an array containing objects like this:

field	meaning
color	rgb color representation
score	Image-specific score for this color. Value in range [0, 1]
pixelFraction	Stores the fraction of pixels the color occupies in the image. Value in range [0, 1]. !

I can't understand the score property meaning and how it is calculated.
In many cases the score value is not related to the pixelFraction value.

thanks in advance

@jgeewax

(link: https://cloud.google.com/vision/reference/rest/v1/images/annotate#ColorInfo)

@jgeewax anyone from the Vision team that can clarify?

hi, any news??

@mik115

Hey @mik115 - going to dig on this for you and hopefully update our docs to be a bit more clear. Score is typically a "confidence level" (ie, "I'm 90% sure this picture is of a dog"), but I can see the confusion this might be causing. Hang tight -- going to figure it out :)

hi, any news about my question?
Thanks

Hello guys!
Any answer here?
In my honest opinion this is a key question and should be answered asap!

@jgeewax

@jgeewax anyone from the Vision team who can help?

@jgeewax

Going to close since this isn't an issue with our library. But feel free to stay tuned if @jgeewax or @omaray can find an answer.

What google vision API provides us is the color, score and pixel fraction. Can we have a formulla to get the percentage of the color.

@zubairshokh

@zubairshokh do you mean the percentage of pixels of a color across the entire image? I believe that is what we calculate as coverage:

var img = 'https://camo.githubusercontent.com/e7653451a451dd7219ffbfddccab39daac4aead4/687474703a2f2f636f6f6c626c61636b7070742e636f6d2f77702d636f6e74656e742f75706c6f6164732f3235363078313434302d636f6e676f2d70696e6b2d636f6f6c2d626c61636b2d616e642d636f6f6c2d677265792d74687265652d636f6c6f722d6261636b67726f756e642d32303135303230353031303935362d353464326332653432613935362e6a7067'

vision.detectProperties(img, { verbose: true }, function(err, props) {
  if (err) throw err
  props = [
    {
      score: 97.700495,
      hex: '002e62',
      red: undefined,
      green: 46,
      blue: 98,
      coverage: 32
    },
    {
      score: 0.76268637,
      hex: '8990ab',
      red: 137,
      green: 144,
      blue: 171,
      coverage: 33.333334
    },
    {
      score: 1.5368186000000001,
      hex: '0a3567',
      red: 10,
      green: 53,
      blue: 103,
      coverage: 1.3333334000000001
    },
    {
      score: 5.019082e-7,
      hex: 'f88379',
      red: 248,
      green: 131,
      blue: 121,
      coverage: 32.666665
    },
    {
      score: 2.0494233e-8,
      hex: 'e87e77',
      red: 232,
      green: 126,
      blue: 119,
      coverage: 0.6666666800000001
    }
  ]  
})

@stephenplusplus

@stephenplusplus But here is what I get .

`Vision.Images.Annotate annotate =
            vision.images()
                    .annotate(new BatchAnnotateImagesRequest().setRequests(ImmutableList.of(request)));

   BatchAnnotateImagesResponse batchResponse = annotate.execute();`



`{
"dominantColors" : {
    "colors" : [ 
        {
            "color" : {
                "blue" : 171.0,
                "green" : 233.0,
                "red" : 241.0
            },
            "pixelFraction" : 0.0413596630096436,
            "score" : 0.33846253156662
        }, 
        {
            "color" : {
                "blue" : 96.0,
                "green" : 50.0,
                "red" : 48.0
            },
            "pixelFraction" : 0.208271935582161,
            "score" : 0.0438975356519222
        }, 
        {
            "color" : {
                "blue" : 121.0,
                "green" : 119.0,
                "red" : 128.0
            },
            "pixelFraction" : 0.0259357504546642,
            "score" : 0.00990148447453976
        }, 
        {
            "color" : {
                "blue" : 193.0,
                "green" : 238.0,
                "red" : 241.0
            },
            "pixelFraction" : 0.0325179286301136,
            "score" : 0.182118445634842
        }, 
        {
            "color" : {
                "blue" : 162.0,
                "green" : 235.0,
                "red" : 239.0
            },
            "pixelFraction" : 0.015227428637445,
            "score" : 0.129081636667252
        }, 
        {
            "color" : {
                "blue" : 141.0,
                "green" : 204.0,
                "red" : 218.0
            },
            "pixelFraction" : 0.020827192813158,
            "score" : 0.0650643929839134
        }, 
               ]
}

}`

Oh, I see. Is that another client library from a different language?

All we do is pixelFraction * 100: https://github.com/GoogleCloudPlatform/google-cloud-node/blob/6c1ebc0a43feb21279808304b515d139ef29ab41/packages/vision/src/index.js#L1525

@jgeewax

@jgeewax Thank you. Lot of confusions are clear by your explanation. 👍

Given that explanation, we probably shouldn't change our formula to consider the score of an annotation. I imagine most use cases will be technical, and the precise number of pixels is what's wanted. As always, the score and raw API response is available in the same callback as our decorated response for the other use cases.

@jgeewax

@jgeewax Thanks for this explanation. I'm trying to find more info on the type of RGB space used for the colors. Can you tell me what code you looked at that allowed you to figure out what "score" meant. It may be what I'm looking for

fix(deps): set min version of node-fetch to 2.6.7 (#1324)