What is the unit of bitmap.getWidth() or bitmap.getHeight()

Question

The developers website simply states that getHeight() will return the bitmap's height, but can someone tell me that is in pixel unit or dp unit?

Solution 1

It's pixel. In Java code you usually work with pixels, e.g. a view's width and height.

Solution 2

bitmap.getWidth() returns width in dp unit or densitiy.

To get dpi (density per inch) for a device, use

float dpi = context.getResources().getDisplayMetrics().density;

To convert dp to px

float px = dp * dpi;

and to convert px to dp

float dp = px/dpi;

Solution 3

After Hours of Experimenting I found that it actually return height in dp units.You can verify it by changing the device screen in emulator.

Comments

[Neoh]

That is view.getHeight(), not bitmap. The downvote is ridiculous, I won't ask this if I can easily google that information.

[Vulovic Vukasin]

its actually in density pixels.

[Zanna]

DPI = Dot Per Inch; px = dp * DPI / 160

[Saravana Kumar K R]

@Zanna what is the need for dividing it by 160?

[Zanna]

1dp corresponds to about (not exactly) 1/160 inch (0.15875mm). Or 1dp corresponds to 1px on a screen resolution of 160DPI (DENSITY_MEDIUM). Your formula is correct, but the variable name "dpi", float dpi = DisplayMetrics().density, is misleading, because that is a scale factor, according to the documentation (and it is not even a density, despite its name). The screen resolution (the linear density of pixels on the unit length of an inch) is generally expressed in DPI and it is in DisplayMetrics.densityDpi. While DisplayMetrics.density = DisplayMetrics.densityDpi / 160, is a scale factor.

[knjk04]

@VulovicVukasin I don't think it is. I just logged the height and width of a bitmap and then compared the output to the height and width given by the details of an image from a file manager (which I presume gives it in pixels). They match, so I think it is pixels.

[gregoiregentil]

How is it possible a selected answer with 15 up votes is a WRONG answer? It's in dp not in pixel.

[Emmanuel Conradie]

This is the wrong way around