sprite vs texture

Hi, I am developing a 2D game, when i importing a png image to unity with the size of 400KB 1024x768 - it becomes 4MB as sprite and when i change it to texture mode, its size becomes 0.7MB in unity, why sprite showing this much size. Will the build size be reduced when i use textures in plane with material instead of sprites?

Thanks in advance,
Ben

Here’s a couple reasons why it might be balooning up:

  1. Mip maps. Basically smaller versions of the textures are created for long-distance viewing without crappy pixel interpolation. Remove or reduce them to get some space back.
  2. Auto-sizing. Graphics cards only really like textures that are sized in powers of 2. I’m not 100% sure that Unity automatically resizes, but I think it does, so it would store your texture as 1024x1024.
  3. Compression. Unity does not use the default encoding from the input file. In the bottom of the inspector window for the texture, you’ll see the compression and sizing settings. If uncompressed, it’s basically stored like a bitmap. You can try changing the compression settings to find one that strikes a good balance for you.