yuv分量提取(NDK:libyuv)
程序员文章站
2022-09-16 21:09:19
通过ImageReader获得数据来源借助libyuv做转换Image image = mImageReader.acquireLatestImage()图片格式决定了image里面planes有几个数组如下: /** * Only a subset of the formats defined in * {@link android.graphics.ImageFormat ImageFormat} and * {@link android.graphics.P...
通过ImageReader获得数据来源借助libyuv做转换
Image image = mImageReader.acquireLatestImage()
图片格式决定了image里面planes有几个数组
如下:
/**
* Only a subset of the formats defined in
* {@link android.graphics.ImageFormat ImageFormat} and
* {@link android.graphics.PixelFormat PixelFormat} are supported by
* ImageReader. When reading RGB data from a surface, the formats defined in
* {@link android.graphics.PixelFormat PixelFormat} can be used; when
* reading YUV, JPEG, HEIC or raw sensor data (for example, from the camera
* or video decoder), formats from {@link android.graphics.ImageFormat ImageFormat}
* are used.
*/
public static int getNumPlanesForFormat(int format) {
switch (format) {
case ImageFormat.YV12:
case ImageFormat.YUV_420_888:
case ImageFormat.NV21:
return 3;
case ImageFormat.NV16:
return 2;
case PixelFormat.RGB_565:
case PixelFormat.RGBA_8888:
case PixelFormat.RGBX_8888:
case PixelFormat.RGB_888:
case ImageFormat.JPEG:
case ImageFormat.YUY2:
case ImageFormat.Y8:
case ImageFormat.Y16:
case ImageFormat.RAW_SENSOR:
case ImageFormat.RAW_PRIVATE:
case ImageFormat.RAW10:
case ImageFormat.RAW12:
case ImageFormat.DEPTH16:
case ImageFormat.DEPTH_POINT_CLOUD:
case ImageFormat.RAW_DEPTH:
case ImageFormat.DEPTH_JPEG:
case ImageFormat.HEIC:
return 1;
case ImageFormat.PRIVATE:
return 0;
default:
throw new UnsupportedOperationException(
String.format("Invalid format specified %d", format));
}
}
以上为ImageUtility里面给出的线索,故从此之后再也不愁应该在image的planes里面取几组数据了。
RGBA_8888
如上,只需要取planes[0]就好。
if (image.getFormat() == PixelFormat.RGBA_8888) {
ByteBuffer byteBuffer = image.getPlanes()[0].getBuffer();
byte[] bytes = new byte[byteBuffer.limit()];
byteBuffer.get(bytes);
enCodeSource(bytes, image.getWidth(), image.getHeight(), bytes.length);
return super.loop();
}
//native
public native void enCodeSource(byte[] buffer, int width, int height, int size);
native层
extern "C"
JNIEXPORT void JNICALL
Java_com_freeme_cloudmirror_daemon_VideoServer3_enCodeSource(JNIEnv *env, jobject thiz,
jbyteArray buffer, jint width,
jint height, jint size) {
uint8_t *rgbBuffer = (unsigned char *) env->GetByteArrayElements(buffer, NULL);
int y_length = width * height;
int u_length = (width * height) / 4;
int v_length = u_length;
uint8_t *y = (unsigned char *) malloc(y_length);
uint8_t *u = (unsigned char *) malloc(u_length);
uint8_t *v = (unsigned char *) malloc(v_length);
LOGE("y:%d \r u:%d \r v:%d \r size:%d",y_length,u_length,v_length,size);
libyuv::ARGBToI420(rgbBuffer, width * 4, y, width, u, (width + 1) / 2, v,
(width + 1) / 2, width, height);
}
参数记录
/**
ARGB little endian (bgra in memory) to I420.
src_argb:用于待转换的argb数据。
src_stride_argb:argb数据每一行的大小,如果是argb_8888格式的话这个值为 width * 4,argb4444的话值为 width * 2。
dst_y:用于保存y分量数据。
dst_stride_y:值为 width * height。
dst_u:用于保存u分量数据。
dst_stride_u:值为(width+1)/2。
dst_v:用于保存分量数据。
dst_stride_v:值为(width+1)/2。
width:位图宽度。
height:位图高度。
*/
LIBYUV_API
int ARGBToI420(const uint8* src_frame, int src_stride_frame,
uint8* dst_y, int dst_stride_y,
uint8* dst_u, int dst_stride_u,
uint8* dst_v, int dst_stride_v,
int width, int height);
YUV_420_888
final Image.Plane[] planes = image.getPlanes();
int width = image.getWidth();
int height = image.getHeight();
byte[] yBytes = new byte[width * height];//y分量
int dstIndex = 0;
byte uBytes[] = new byte[width * height / 4];//u分量
byte vBytes[] = new byte[width * height / 4];//v分量
int uIndex = 0;
int vIndex = 0;
int pixelsStride, rowStride;
for (int i = 0; i < planes.length; i++) {
pixelsStride = planes[i].getPixelStride();
rowStride = planes[i].getRowStride();
ByteBuffer buffer = planes[i].getBuffer();
byte[] bytes = new byte[buffer.capacity()];
buffer.get(bytes);
int srcIndex = 0;
if (i == 0) {
for (int j = 0; j < height; j++) {
System.arraycopy(bytes, srcIndex, yBytes, dstIndex, width);
srcIndex += rowStride;
dstIndex += width;
}
} else if (i == 1) {
for (int j = 0; j < height / 2; j++) {
for (int k = 0; k < width / 2; k++) {
uBytes[uIndex++] = bytes[srcIndex];
srcIndex += pixelsStride;
}
if (pixelsStride == 2) {
srcIndex += rowStride - width;
} else if (pixelsStride == 1) {
srcIndex += rowStride - width / 2;
}
}
} else if (i == 2) {
for (int j = 0; j < height / 2; j++) {
for (int k = 0; k < width / 2; k++) {
vBytes[vIndex++] = bytes[srcIndex];
srcIndex += pixelsStride;
}
if (pixelsStride == 2) {
srcIndex += rowStride - width;
} else if (pixelsStride == 1) {
srcIndex += rowStride - width / 2;
}
}
}
}
本文地址:https://blog.csdn.net/qq_33717425/article/details/107180621
下一篇: Git分支合并冲突解决的方法实现