I am using jcrop for the first time. ANd I have a problem with image size and cropping. When user upload image 1366×768 or larger I preview it on my page. I also have crop selection preview and it works fine. When I submit positions it crops fine (it’s when I use original image size).
But I don’t want to display so large original images on page. User must see original image, preview and submit buttons in one view. So I need to make image smaller if image is 1366×768 I wan’t to display it like 683×368. But here is the problem. When I set width and height on image tag crop not works fine anymore. I paste my code and image preview of my problem:
jQuery(window).load(function () {
jQuery('#cropbox').Jcrop({
onChange: showPreview,
onSelect: showPreview,
setSelect: [0, 0, 540, 300],
allowResize: true,
aspectRatio: 2
});
});
function showPreview(coords) {
if (parseInt(coords.w) > 0) {
var rx = 540 / coords.w;
var ry = 300 / coords.h;
jQuery('#preview').css({
width: Math.round(rx * 683) + 'px',
height: Math.round(ry * 368) + 'px',
marginLeft: '-' + Math.round(rx * coords.x) + 'px',
marginTop: '-' + Math.round(ry * coords.y) + 'px'
});
}
$('#x').val(coords.x);
$('#y').val(coords.y);
$('#w').val(coords.w);
$('#h').val(coords.h);
}
</script>
</head>
<body>
<div>
<p style="width: 540px; height: 300px; overflow: hidden; float:left;">
<img id="preview" src="../../Content/Images/Full/Leopard.jpg" />
</p>
<p style="float:left;">
<img id="cropbox" width="683px" height="368px" src="../../Content/Images/Full/Leopard.jpg" />
</p>
<p>
@using (@Html.BeginForm("PostPicture", "Home"))
{
<input type="hidden" id="x" name="x" />
<input type="hidden" id="y" name="y" />
<input type="hidden" id="w" name="w" />
<input type="hidden" id="h" name="h" />
<button type="submit">
Send</button>
}
</p>

This is second error: After I multiply X and Y with 2.

This is asp.net back end code:
public ImageResult PostPicture(int x, int y, int h, int w)
{
x = x * 2;
y = y * 2;
Image image = Image.FromFile(Path.Combine(this.Request.PhysicalApplicationPath, "Content\\Images\\Full\\Leopard.jpg"));
Bitmap cropedImage = new Bitmap(w, h, image.PixelFormat);
Graphics g = Graphics.FromImage(cropedImage);
Rectangle rec = new Rectangle(0, 0,
w,
h);
g.DrawImage(image, rec, x, y, w, h, GraphicsUnit.Pixel);
image.Dispose();
g.Dispose();
string savedFileName = Path.Combine(
AppDomain.CurrentDomain.BaseDirectory,
"Content", "Images", "Full",
Path.GetFileName("cropped.jpg"));
cropedImage.Save(savedFileName);
return new ImageResult { Image = cropedImage, ImageFormat = ImageFormat.Jpeg };
}
Maybe try setting the image size in css style attribute:
Perhaps a better solution is to resize the image on the server to your desired dimensions, then display the resized image to the user instead of the full original image. This will also reduce download time for the browser since the image will be smaller.