android.media.effect
Provides classes that allow you to apply a variety of visual effects to images and videos. For example, you can easily fix red-eye, convert an image to grayscale, adjust brightness, adjust saturation, rotate an image, apply a fisheye effect, and much more. The system performs all effects processing on the GPU to obtain maximum performance.
For maximum performance, effects are applied directly to OpenGL textures, so your application must have a valid OpenGL context before it can use the effects APIs. The textures to which you apply effects may be from bitmaps, videos or even the camera. However, there are certain restrictions that textures must meet:
- They must be bound to a
GL_TEXTURE_2D
texture image - They must contain at least one mipmap level
An
Effect
object defines a single media effect that you can apply to an image frame. The basic workflow to create anEffect
is:- Call
EffectContext.createWithCurrentGlContext()
from your OpenGL ES 2.0 context. - Use the returned
EffectContext
to callEffectContext.getFactory()
, which returns an instance ofEffectFactory
. - Call
createEffect()
, passing it an effect name from @link android.media.effect.EffectFactory}, such asEFFECT_FISHEYE
orEFFECT_VIGNETTE
.
You can adjust an effect’s parameters by calling
setParameter()
and passing a parameter name and parameter value. Each type of effect accepts different parameters, which are documented with the effect name. For example,EFFECT_FISHEYE
has one parameter for the scale
of the distortion.
To apply an effect on a texture, call
apply()
on the Effect
and pass in the input texture, its width and height, and the output texture. The input texture must be bound to a GL_TEXTURE_2D
texture image (usually done by calling theglTexImage2D()
function). You may provide multiple mipmap levels. If the output texture has not been bound to a texture image, it will be automatically bound by the effect as a GL_TEXTURE_2D
and with one mipmap level (0), which will have the same size as the input.
Note: All effects listed in
EffectFactory
are guaranteed to be supported. However, some additional effects available from external libraries are not supported by all devices, so you must first check if the desired effect from the external library is supported by calling isEffectSupported()
.
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