Develop Reference

description preview of uploaded images

I would like to add to the preview of uploaded images before uploading to the server the option to add a description of the image, which will be saved in the database, below the script displaying images and a preview image. Is anyone able to help me ?
$(function() {
// Multiple images preview with JavaScript
var multiImgPreview = function(input, imgPreviewPlaceholder) {
if (input.files) {
var filesAmount = input.files.length;
for (i = 0; i < filesAmount; i++) {
var reader = new FileReader();
reader.onload = function(event) {
$($.parseHTML('<img>')).attr('src', event.target.result).appendTo(imgPreviewPlaceholder);
}
reader.readAsDataURL(input.files[i]);
}
}
};
$('#chooseFile').on('change', function() {
multiImgPreview(this, 'div.imgGallery');
});
});
enter image description here

Can't recognize image using OCR

I was trying to use ocrad.js to convert an image to a string, but I didn't get the result string. I was also previewing the image, the problem is only in the image recognition.
This is my code:
function pr_image(event) {
var reader = new FileReader();
reader.onload = function() {
var output = document.getElementById('output_image');
output.src = reader.result;
}
reader.readAsDataURL(event.target.files[0]);
var stringletter = OCRAD(event.target.files[0]);
document.getElementById('letter').value = stringletter;
}
and this is the browser's capture:
unchanged value
no error message in console
I've tried to change the recognition code into this one function, but i get . as the image recognition's result:
function str_img(event) {
var canvas = document.createElement('canvas');
var context = canvas.getContext('2d');
var img = new Image();
img.onload = function() {
context.drawImage(this, 0, 0);
}
var imageData = context.getImageData(0, 0, 100, 100);
var stringletter = OCRAD(imageData);
document.getElementById('letter').value = stringletter;
}
I suspect that I failed at converting the input file as image data. What should I do? Any help is appreciated!
Solved:
I've changed my code into this by Chris G and it works! Thank you
function preview_image(event)
{
var reader = new FileReader();
var output = document.getElementById('output_image');
reader.onload = function()
{
output.src = reader.result;
}
reader.readAsDataURL(event.target.files[0]);
output.onload = function()
{
var stringletter = OCRAD(output);
document.getElementById('letter').value = stringletter;
}
}

Uploading image and displaying it small with javascript

So, I've got this working javascript and it loads an image that a user uploads to the HTML on the screen displaying it.
But, it displays the image without a max height or width so it moves buttons on the page to where they can't be seen or pressed. This includes the submit button if the image uploaded is big enough.
So, is there some way to make the 'uploaded' image display really small: like max 30px in height?
$(function(){
$('#user_avatar').change(function(e){
var files = event.target.files;
var image = files[0];
for (var i = files.length - 1; i >= 0; i--) {
var reader = new FileReader();
var file = files[i];
reader.onload = function(file) {
var img = new Image();
img.src = file.target.result;
$('#inputpic').attr('src', file.target.result);
}
reader.readAsDataURL(image);
};
});
});
I have tried adding:
theimage = getElementById('inputpic')
theimage.style.height='10px';
But this had no effect.
EDIT 1
html.slim that the JS talks to:
= image_tag('temp.png', id: "inputpic", class: 'tiny_image_display')
SCSS that I made:
.tiny-image-display {
max-height: 30px;
}

You can set this in CSS very easily:
#inputpic {
max-height: 30px;
}

$(function(){
$('#user_avatar').change(function(e){
var files = event.target.files;
var image = files[0];
for (var i = files.length - 1; i >= 0; i--) {
var reader = new FileReader();
var file = files[i];
reader.onload = function(file) {
var img = new Image();
img.src = file.target.result;
img.height = "30";
$('#inputpic').attr('src', file.target.result);
}
reader.readAsDataURL(image);
};
});
});

Adding delete button for each image thumbnail preview

I want to put next to each thumbnail a little cross to be able to remove them one by one. I am able to remove image by click on it but I would like to have seperate button "x" to remove it.
fileInput.addEventListener("change", function (e) {
var filesVAR = this.files;
showThumbnail(filesVAR);
}, false);
function showThumbnail(files) {
var file = files[0]
var image = document.createElement("img");
var thumbnail = document.getElementById("thumbnail");
image.file = file;
image.setAttribute('class', 'imgKLIK5');
thumbnail.appendChild(image)
var reader = new FileReader()
reader.onload = (function (aImg) {
return function (e) {
aImg.src = e.target.result;
};
}(image))
var ret = reader.readAsDataURL(file);
var canvas = document.createElement("canvas");
ctx = canvas.getContext("2d");
image.onload = function () {
ctx.drawImage(image, 100, 100);
}
}
});
Here is my code in JFIDDLE
Can You help me out, please?

see this example with close button:http://jsfiddle.net/kevalbhatt18/r0taz01L/1/
$('div').on('click', '.closeDiv', function () {
$(this).prev().remove();
$(this).remove();
$('#upload-file').val("");
});
And I made this changes in your showThumbnail function
function showThumbnail(files) {
var file = files[0]
var thumbnail = document.getElementById("thumbnail");
var pDiv = document.createElement("div");
var image = document.createElement("img");
var div = document.createElement("div");
pDiv.setAttribute('class', 'pDiv');
thumbnail.appendChild(pDiv);
image.setAttribute('class', 'imgKLIK5');
pDiv.appendChild(image)
div.innerHTML = "X";
div.setAttribute('class', 'closeDiv');
pDiv.appendChild(div).......
...................

Just add new button element on each preview with following style attributes,
float:right;
position:relative;

you can remove the img from div thumbnail on click the "x" button, check this fiddle

image,onload event not working in chrome

I'm using html5 to create drag and drop image upload functionality. This works great for me in firefox but in chrome the image onload event only fires the first time. If I drag multiple images in only the first works and if I drag a second in it fails. I believe the problem is with the image onload.
here is the way my code works I have removed the irrelevant sections:
var img = document.createElement("img");
var reader = new FileReader();
var canvas = document.createElement("canvas");
var canvasData;
var ctx = canvas.getContext("2d");
var myFiles;
var i = 0;
reader.onload = (function (aImg)
{
return function (e)
{
aImg.src = e.target.result;
};
})(img);
img.onload = function (){
//resizes image
//draws it to the canvas
//posts to server
i++;
if(i < myFiles.length){
processNext(i);
}
}
function processNext(filei) {
var file = myFiles[filei];
img.file = file;
reader.readAsDataURL(file);
}
i = 0;
myFiles = files;
processNext(0);
Does anyone know why this works in firefox but not chrome?

Explanation from chromium tracker:
This is not a bug. WebKit is just more strict. You must instantiate a new Image() object before the replacement, like this:
var photo = document.getElementById('image_id');
var img = new Image();
img.addEventListener('load', myFunction, false);
img.src = 'http://newimgsource.jpg';
photo.src = img.src;
source: http://code.google.com/p/chromium/issues/detail?id=7731#c12

This is strange, none of the above worked for me. I was defining the image variable as local and change it to global and it started working. Does this make sense? Can somebody explain it?
This didnt worked for me:
function loadImage() {
var ImageToLoad = new Image();
ImageToLoad.onload = function() {
console.log("finish loading");
};
ImageToLoad.src = "myimage.png";
}
This did work:
var ImageToLoad = new Image();
function loadImage() {
ImageToLoad.onload = function() {
console.log("finish loading");
};
ImageToLoad.src = "myimage.png";
}