Images play a very significant
role in any Windows Phone application. So, one should be very careful while
dealing with images. As of now, Windows Phone supports only two image formats
named JPG/JPEG and PNG. Before concluding on which image format to choose,
let's get into bit more depth of it.
PNG format images are non-lossy and need very
little CPU effort to display because those are pixel perfect. But at the same
time, huge PNG images take too much longer to read from storage and ultimately
lead to slower display. On the other hand, JPEG format images are lossy,
smaller to store and based on the compression level much more complicated decoding algorithm
is required to display them.
Another point regarding image is about opacity and
transparency - All the images that use transparency should be stored as
PNG format because JPEG doesn’t support transparency and JPEG format should be
used for all the images that are fully opaque.
Now when coming to Windows Phone apps, performance
matters a lot, isn’t it?
Well, now some of the best tips to make our Windows Phone
app much more performant:
- Choosing proper image format: Use
JPEG for anything large and PNG for anything small, i.e. use PNG for small
icons. If image transparency is not a concern, then it is always
recommended to use JPEG.
- Compiling images with Build
Action=Content: Whenever a new image is added to the project, the
default "Build Action" is set to Resource. It is always recommended
to change this "Build Action" property to Content as it will reduce
the size of our DLL, resulting in speedy image and app loading.
Note: Resources are included in an
assembly whereas content is included in deployment package.
- Image size: One of the limitations of Windows
Phone is the limited screen resolution. So one has to consider proper image
size in order to gain better performance.
I'll keep updating this post
as and when I'll get to know about more interesting facts. I would be very
happy if you can add more to it.