How to make use of it:

1. Include the needed jQuery library, jQuery mousewheel plugin, and hammer.js on the web page.

<script src="/path/to/jquery.min.js"></script>
<script src="/path/to/hammer.min.js"></script>
<script src="/path/to/jquery.mousewheel.min.js"></script>

2. The required HTML structure.

<div id="picview" class="picview">
  // Add Image Here
</div>

3. Include the jQuery ZoomMarker plugin’s JavaScript and CSS information on the web page.

<link rel="stylesheet" href="css/zoom-marker.css">
<script src="js/zoom-marker.js"></script>

4. Initialize the ZoomMarker plugin on doc ready and add your individual markers to the picture as follows:

$(document).ready(function () {
  $('#viewArea').zoomMarker({
    src: "image-to-zoom.jpg",
    rate: 0.2, // from 0 to 1
    markers:[
      {src:"marker.png", x:500, y:500},
      {src:"marker.png", x:200, y:200},
      {src:"marker.png", x:1280, y:720, size:20},
    ]
  });
})

5. All attainable plugin choices:

{

  // mouse scroll speed
  rate: 0.2,

  // path to image
  src: null, 

  // width
  width: 500,

  // min width
  min: 300,

  // max width
  max: null,

  // predefined markers
  // {src:"marker.png", x:100, y:100, size:20, click:fn()}
  markers: [],

  // marker size
  marker_size: 20,

  // enable draggable
  enable_drag: true,

  // auto index
  auto_index_z: true,

  // enable cancas layer
  enable_canvas: false,

  // lock zoom
  zoom_lock: false
  
}

6. API strategies.

// load an image to the document
$('#viewArea').zoomMarker_LoadImage("img/rail.jpg");

// zoom an image
$('#viewArea').zoomMarker_Zoom(center, scale);

// get image size
$('#viewArea').zoomMarker_GetPicSize();

// enable draggable
$('#viewArea').zoomMarker_EnableDrag(enable);

// make the marker always in front of elements
$('#viewArea').zoomMarker_TopIndexZ();

// reset image
$('#viewArea').zoomMarker_ResetImage()

// get canvas
$('#viewArea').zoomMarker_Canvas();

// clear canvas
$('#viewArea').zoomMarker_CanvasClean();

// move marker
$('#viewArea').zoomMarker_Move(x, y);

// clear marker
$('#viewArea').zoomMarker_CleanMarker();

// remove marker
$('#viewArea').RemoveMarker(markerID);

// add custom image markers
$('#viewArea').zoomMarker_AddMarker({
  src:"img/marker.png", 
  x:320, 
  y:180, 
  size:20, 
  hint: {
    value: '',
    style: {}
  }
  dialog: {
    value: '',
    style: {},
    offsetX: 0,
    offsetY: 0
  }
  click:function(e){
    alert(e);
  }
});

7. Events.

$('#viewArea').on("zoom_marker_img_load", function(event, src){
  // when the image stars loading
});

$('#viewArea').on("zoom_marker_img_loaded", function(event, size){
  // after the image has been loaded
});

$('#viewArea').on("zoom_marker_click", function(event, markerObj){
  // when a marker is clicked
});

$('#viewArea').on("zoom_marker_mouse_click", function(event, mouseObj){
  // when the image is clicked
});

$('#viewArea').on("zoom_marker_move_end", function(event, x, y, markerObj){
  // when move end
});

Simple Image Zoom And Annotation Plugin, image zoom on hover, ZoomMarker Plugin/Github

See Demo And Download