Created on July 19, 2013 15:34 | Updated about 7 years ago
Link: https://gist.github.com/jywarren/6040039
Prompts you for a pixel row and # of lines to smooth, and averages them. Does not yet save.
setup: function() {
// code to run on startup
smooth_initiate = function() {
alert('Click on the spectrum image to choose a starting row.')
$('#image').click(function(e){
smooth_complete(e.offsetY)
})
}
smooth_complete = function(row) {
var rows = prompt("How many rows of data below the selected row would you like to average?")
var orig_img = $('#image')[0]
$('body').append("<canvas id='tmp_canvas'></canvas>")
var img = new Image()
img.src = orig_img.src
var canvas = $('#tmp_canvas')[0]
canvas.width = img.width
canvas.height = img.height
var ctx = canvas.getContext("2d")
ctx.drawImage(img,0,0)
var pixels = ctx.getImageData(0,row,canvas.width,rows).data
// now, sum pixels & cheat: just overwrite existing calibrated (or uncalibrated) pixel rows
$.each($W.spectrum['lines'],function(index,line) {
// clear out existing data
line['r'] = 0
line['g'] = 0
line['b'] = 0
// for each row of data, add new data
for (var i=0;i<rows;i++) {
line['r'] += pixels[i*canvas.width*4+index*4]
line['g'] += pixels[i*canvas.width*4+index*4+1]
line['b'] += pixels[i*canvas.width*4+index*4+2]
}
// divide to get average per channel
line['r'] = line['r']/rows
line['g'] = line['g']/rows
line['b'] = line['b']/rows
// average colors to get overall
line['average'] = (line['r'] + line['g'] + line['b'])/3
})
// graph smoothed data:
var graph_data = []
$.each($W.spectrum.lines,function(index,line) {
if (line.wavelength == null) {
line.wavelength = index
}
graph_data.push([line['wavelength'],line['average']/2.55])
})
$W.data.push({label: "Smoothed", data: graph_data})
flotoptions.colors.push("#ff0000")
$W.plot = $.plot($("#graph"),$W.data,flotoptions);
// upload and save, refresh page
// not quite yet
}
smooth_initiate()
},
draw: function() {
// code to run every frame
}