public abstract class Image
extends Object
implements AutoCloseable
java.lang.Object | |
↳ | android.media.Image |
A single complete image buffer to use with a media source such as a MediaCodec
or a CameraDevice
.
This class allows for efficient direct application access to the pixel data of the Image through one or more ByteBuffers
. Each buffer is encapsulated in a Image.Plane
that describes the layout of the pixel data in that plane. Due to this direct access, and unlike the Bitmap
class, Images are not directly usable as as UI resources.
Since Images are often directly produced or consumed by hardware components, they are a limited resource shared across the system, and should be closed as soon as they are no longer needed.
For example, when using the ImageReader
class to read out Images from various media sources, not closing old Image objects will prevent the availability of new Images once the maximum outstanding image count
is reached. When this happens, the function acquiring new Images will typically throw an IllegalStateException
.
See also:
Nested classes |
|
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class |
Image.Plane A single color plane of image data. |
Public methods |
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abstract void |
close() Free up this frame for reuse. |
Rect |
getCropRect() Get the crop rectangle associated with this frame. |
abstract int |
getFormat() Get the format for this image. |
abstract int |
getHeight() The height of the image in pixels. |
abstract Plane[] |
getPlanes() Get the array of pixel planes for this Image. |
abstract long |
getTimestamp() Get the timestamp associated with this frame. |
abstract int |
getWidth() The width of the image in pixels. |
void |
setCropRect(Rect cropRect) Set the crop rectangle associated with this frame. |
void |
setTimestamp(long timestamp) Set the timestamp associated with this frame. |
Inherited methods |
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![]() java.lang.Object
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![]() java.lang.AutoCloseable
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void close ()
Free up this frame for reuse.
After calling this method, calling any methods on this Image
will result in an IllegalStateException
, and attempting to read from or write to ByteBuffers
returned by an earlier getBuffer()
call will have undefined behavior. If the image was obtained from ImageWriter
via dequeueInputImage()
, after calling this method, any image data filled by the application will be lost and the image will be returned to ImageWriter
for reuse. Images given to queueInputImage()
are automatically closed.
Rect getCropRect ()
Get the crop rectangle associated with this frame.
The crop rectangle specifies the region of valid pixels in the image, using coordinates in the largest-resolution plane.
Returns | |
---|---|
Rect |
int getFormat ()
Get the format for this image. This format determines the number of ByteBuffers needed to represent the image, and the general layout of the pixel data in each in ByteBuffer.
The format is one of the values from ImageFormat
. The mapping between the formats and the planes is as follows:
Format | Plane count | Layout details |
---|---|---|
JPEG |
1 | Compressed data, so row and pixel strides are 0. To uncompress, use BitmapFactory#decodeByteArray . |
YUV_420_888 |
3 | A luminance plane followed by the Cb and Cr chroma planes. The chroma planes have half the width and height of the luminance plane (4:2:0 subsampling). Each pixel sample in each plane has 8 bits. Each plane has its own row stride and pixel stride. |
YUV_422_888 |
3 | A luminance plane followed by the Cb and Cr chroma planes. The chroma planes have half the width and the full height of the luminance plane (4:2:2 subsampling). Each pixel sample in each plane has 8 bits. Each plane has its own row stride and pixel stride. |
YUV_444_888 |
3 | A luminance plane followed by the Cb and Cr chroma planes. The chroma planes have the same width and height as that of the luminance plane (4:4:4 subsampling). Each pixel sample in each plane has 8 bits. Each plane has its own row stride and pixel stride. |
FLEX_RGB_888 |
3 | A R (red) plane followed by the G (green) and B (blue) planes. All planes have the same widths and heights. Each pixel sample in each plane has 8 bits. Each plane has its own row stride and pixel stride. |
FLEX_RGBA_8888 |
4 | A R (red) plane followed by the G (green), B (blue), and A (alpha) planes. All planes have the same widths and heights. Each pixel sample in each plane has 8 bits. Each plane has its own row stride and pixel stride. |
RAW_SENSOR |
1 | A single plane of raw sensor image data, with 16 bits per color sample. The details of the layout need to be queried from the source of the raw sensor data, such as CameraDevice . |
RAW_PRIVATE |
1 | A single plane of raw sensor image data of private layout. The details of the layout is implementation specific. Row stride and pixel stride are undefined for this format. Calling getRowStride() or getPixelStride() on RAW_PRIVATE image will cause UnSupportedOperationException being thrown. |
Returns | |
---|---|
int |
See also:
int getHeight ()
The height of the image in pixels. For formats where some color channels are subsampled, this is the height of the largest-resolution plane.
Returns | |
---|---|
int |
Plane[] getPlanes ()
Get the array of pixel planes for this Image. The number of planes is determined by the format of the Image. The application will get an empty array if the image format is PRIVATE
, because the image pixel data is not directly accessible. The application can check the image format by calling getFormat()
.
Returns | |
---|---|
Plane[] |
long getTimestamp ()
Get the timestamp associated with this frame.
The timestamp is measured in nanoseconds, and is normally monotonically increasing. The timestamps for the images from different sources may have different timebases therefore may not be comparable. The specific meaning and timebase of the timestamp depend on the source providing images. See Camera
, CameraDevice
, MediaPlayer
and MediaCodec
for more details.
Returns | |
---|---|
long |
int getWidth ()
The width of the image in pixels. For formats where some color channels are subsampled, this is the width of the largest-resolution plane.
Returns | |
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int |
void setCropRect (Rect cropRect)
Set the crop rectangle associated with this frame.
The crop rectangle specifies the region of valid pixels in the image, using coordinates in the largest-resolution plane.
Parameters | |
---|---|
cropRect |
Rect
|
void setTimestamp (long timestamp)
Set the timestamp associated with this frame.
The timestamp is measured in nanoseconds, and is normally monotonically increasing. The timestamps for the images from different sources may have different timebases therefore may not be comparable. The specific meaning and timebase of the timestamp depend on the source providing images. See Camera
, CameraDevice
, MediaPlayer
and MediaCodec
for more details.
For images dequeued from ImageWriter
via dequeueInputImage()
, it's up to the application to set the timestamps correctly before sending them back to the ImageWriter
, or the timestamp will be generated automatically when queueInputImage()
is called.
Parameters | |
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timestamp |
long : The timestamp to be set for this image. |