Saving large images created in Flex - apache-flex

I am attempting to capture a very large image that was made dynamically within the Flash Player (the size of the image is 2400px by 12,000px) and am running into some very serious issues... Let me run down how the image get's to that size in the first place:
User adds elements to a canvas and then when the user is finished the canvas scales up to 2400px wide and ~12,000px tall. The problem arises when I attempt to save the image to the hard drive. Now, I dont know if this will affect the recommended fix, but the rendered image wont be saved on the hard drive, it will be sent to a server. I know about the ~4050px limit in Flash Player and was thinking I could get around that by clipping the images with the ImageSnapshot.captureBitmapData() method and keeping the required Rectangle variable below 4000px then repeat that down the large image until it reaches the end where the final images will be pieced together at a later time. However... As i mentioned the error comes when it reaches the 'fileReference.save(pngImage);' method... Has anyone else done something like this?

Have you tried if fileReference.save works at all (e.g. with smaller images like 100 px height)? It seems that the image data will perhaps be transformed to string data, so there might be other limits you're not aware of at the moment (your uncompressed image data will be around 86 MB, so even a PNG file with good compression might be around 10 MB in size, at the moment you're trying to save a third of this, but 3 MB still is quite large).

Related

CSS Sprite file is too big to handle

I know reducing your requests to the server will help reduce load time. Placing all of your images into a sprite can really help with this. However, when is a sprite too big?
The sprite for my page is 1.7mb! I thought about splitting the sprite up into smaller sprites. That will increase server requests and would seem to be a pointless task.
My site loads too slow and I’m trying to pinpoint the slow downs.
Can anyone suggest how should I handle one big sprite? should I break it into multiple files or is there any other suggestion to improve the page load time.
The best size is 4096 x 4096 What is the maximum sprite sheet size I can use for android devices?
So long as you are using fewer pixels than that, you should be fine. The only logical reason to break up your sprite images smaller than that is if you want to give the user an image to look at while they wait for the others to load. (Or if there are some images you know some users will never see on their visit.) But it will increase the loading time overall.
As for file size, add compression to your personal taste. If your hatred of the loading time and your hatred of the compression artefacts are equal, you have found the right balance.

image resource taking long to load

My site is taking a long time to load. It is quite resource intensive but upon checking a waterfall of the site load I have two images that take a very long time to load.
http://www.webpagetest.org/result/170919_0K_df1a409e4603bc6459c19cc03cc19aea/2/details/#waterfall_view_step1
I have scaled the images in the WP media image editor so that they are a reasonable size but the waterfall still shows long load times on those images?
www.linestar.ca
Any insights are appreciated!
Though you resized the image in wp, that doesn't really change the file size. I downloaded your dark banner photo and it was 12.8mb. That's huge and takes a long time to load. Try and get your images around 500kb or less. It should still be pretty clear at 200kb even. It will still have decent quality at those levels. Your image size is also huge, at 1920X3000. Definitely doesn't need to be that large. Check out this link for a rough idea of sizing: Image sizing for background images

Does Image sprite size matters

Currently I am using a image sprite having size of 200K and its load time is 4.9 second.
My Question is,
Does the sprite image size matters while loading?
If the size is increasing, Can we break it in to two or three image sprite?
What would be the best option increasing the HTTP request or doing some compression?
Thanks
It matters if you want certain images to show up before others. Obviously no images can be shown until the whole thing loads. If there are elements of particular importance then break them into a separate file.
Yes
Compression won't get you very much because you are probably already using a compressed image format like jpeg or png.
If you need to optimize page load speed I would do my suggestion in point one and possibly use async requests for remaining images.

Loading high res background image

I have a colourful background image that is 2000px x 1500px and because of the details I am saving it as a jpeg that renders at 1.1 MB. I am using the CSS background property to render the image. So being relatively new to web dev and working with a client/designer that's not open to a change of design at this point in the process, what should I do to help this image load blazingly fast. I don't know if it makes a difference but the site is using Joomla 1.5.9. This is something I've always wanted to understand but have had trouble uncovering solutions for... I hope someone can help!!
Thanks everyone!
There's no way to make images magically load faster. Sometimes, though, splitting an image in smaller images allows for surprising size gains; so if it's not out of question for your CSS layout (it typically is, though), you could try this.
Another possibility for you would be to use progressive JPEG images. They are encoded in such a way that enables browsers to display a progressively more precise image as it loads. This means that at first, the image appears blurry (or incomplete) but with full-dimensions, then it progressively gets sharper and better. It's well-suited for images meant to load slowly (or at least, images acknowledged to load slowly).
The best thing that you can do is try to shrink the file size to as small as possible. Let this be using some type of optimizer, smush.it for example. If you created the background image try saving it as progressive first, it loads a lower res version first then finishes loading. But the best thing is to try to shrink the size of the image width and height by finding a repeating pattern and cropping just that portion out and using it. Most about.me images are no larger than 100kb in size that are above 1200px wide.
you could immediatley call the image in the head by using
<script>
(new Image()).src = "IMAGE PATH";
</script>
and make sure you compress the image as much as you can with different programs, or if you have photoshop cs5 you can save it for a web device to strip out all of the extra junk, you can try yahoo's smush.it
http://www.smushit.com/ysmush.it/
or you could delay the loading of the site entirely for a few seconds, until you can be sure that the image is loading, you could try something like hiding all of the elements and fading them in upon a setTimeout something like
*CSS
body{
opacity:0;
}
*jQuery
setTimeout(function(){$('body').animate({opacity:'1'},300)},5000);
although that may not be all that practical.
Would loading the background image after the rest of the page has loaded work for you? At least this way visitors will be able to use the rest of your site until the 1.1MB has loaded.
Something along the lines of setting the style attribute of the <body> to be background: url(image.jpg) within an onload function?
Delivering the image over a CDN will likely speed things up; the better ones are usually optimized to deliver the proper TCP packet size/MTU to the wide variety of clients out there and have generally done a lot of work in the details of delivering things quickly. Slow connections like cellphones will still hate you for it, but getting things like packet size right can make the most of the bandwidth that is available.

Displaying huge, scrollable images in Image?

I'm trying to show image files (jpg, png, gif) that can be larger than the available display area. I've embedded an Image inside a cCanvas (to get scrolling), but the large images are not completely displayed.
Very large images (e.g. 2480 x 3507) have the top or the top and bottom of the image clipped withing the scrolling Image.
What is the largest graphic one can display using the mx.controls.Image ?
Thanks
The 2880 pixels limit is for BitmapDatas, for DisplayObjects there's a limit of 8191 pixels.
You can bypass these limits by using the BitmapDataUnlimited-class available here: http://code.google.com/p/bitmapdataunlimited/
However, if performance is important I'd recommend letting such large images consist of multiple smaller ones instead. Even if you don't reuse these smaller ones or take care of removing them from the displayList or setting their visible-property to false there will still be a performance gain as flash automatically detects that they're outside of the stage and wont have to be rendered.
Edit:
I forgot saying that the 2880px-limit only applies when manually creating BitmapDatas, images bigger than that can still be loaded in, and their BitmapDatas (which are bigger than 2880px) can be accessed and manipulated.
You could easily have a Bitmap with a bitmapData as large as the viewport, then you can set its bitmapData by doing something like:
viewportBitmapData.copyPixels(sourceBitmapData, new Rectangle(x,y,viewportWidth, viewPortHeight), new Point(0,0))
When scrolling, you could simply do the above on each frame
Or if performance is important, you can when scrolling (if scrollingDistance is less than viewportSize) use viewportBitmapData.scroll(x,y) to shift the whole bitmapData, and then copy only the new pixels.
I've read that the limit is 2880 pixels per dimension in Flash 9. In Flash 10 the limit is higher. Check to see which version you're compiling for.
You could potentially chop the image into smaller pieces and assemble them in Flex.
If makes a difference which FlashPlayer you are targetting:
versions VS maximum bitmapsize
flashplayer -9 : 2880x2880 px
flashplayer 10 : 4096x4096 px
flashplayer 11 : unlimited

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