Android Camera Preview ANativeWindow的處理
從JNI的調用看，Java經過surfacetexture來顯示preview。CameraService經過surfacetexture獲取ANativeWindow，向OpenGL傳遞數據。 java
ANativeWindow的函數實現是在CameraHardwareInterface.h中， android
struct camera_preview_window {
struct preview_stream_ops nw;
void *user;
};
struct camera_preview_window mHalPreviewWindow;
preview_stream_ops 的定義在hardware/libhardware/include/hardware/camera.h中 app
typedef struct preview_stream_ops {
int (*dequeue_buffer)(struct preview_stream_ops* w,
buffer_handle_t** buffer, int *stride);
int (*enqueue_buffer)(struct preview_stream_ops* w,
buffer_handle_t* buffer);
int (*cancel_buffer)(struct preview_stream_ops* w,
buffer_handle_t* buffer);
int (*set_buffer_count)(struct preview_stream_ops* w, int count);
int (*set_buffers_geometry)(struct preview_stream_ops* pw,
int w, int h, int format);
int (*set_crop)(struct preview_stream_ops *w,
int left, int top, int right, int bottom);
int (*set_usage)(struct preview_stream_ops* w, int usage);
int (*set_swap_interval)(struct preview_stream_ops *w, int interval);
int (*get_min_undequeued_buffer_count)(const struct preview_stream_ops *w,
int *count);
int (*lock_buffer)(struct preview_stream_ops* w,
buffer_handle_t* buffer);
// Timestamps are measured in nanoseconds, and must be comparable
// and monotonically increasing between two frames in the same
// preview stream. They do not need to be comparable between
// consecutive or parallel preview streams, cameras, or app runs.
int (*set_timestamp)(struct preview_stream_ops *w, int64_t timestamp);
} preview_stream_ops_t; 在CameraHardwareInterface.h中的初始化函數中，調用initHalPreviewWindow()
status_t initialize(hw_module_t *module)
{
ALOGI("Opening camera %s", mName.string());
int rc = module->methods->open(module, mName.string(),
(hw_device_t **)&mDevice);
if (rc != OK) {
ALOGE("Could not open camera %s: %d", mName.string(), rc);
return rc;
}
initHalPreviewWindow();
return rc;
}
void initHalPreviewWindow()
{
mHalPreviewWindow.nw.cancel_buffer = __cancel_buffer;
mHalPreviewWindow.nw.lock_buffer = __lock_buffer;
mHalPreviewWindow.nw.dequeue_buffer = __dequeue_buffer;
mHalPreviewWindow.nw.enqueue_buffer = __enqueue_buffer;
mHalPreviewWindow.nw.set_buffer_count = __set_buffer_count;
mHalPreviewWindow.nw.set_buffers_geometry = __set_buffers_geometry;
mHalPreviewWindow.nw.set_crop = __set_crop;
mHalPreviewWindow.nw.set_timestamp = __set_timestamp;
mHalPreviewWindow.nw.set_usage = __set_usage;
mHalPreviewWindow.nw.set_swap_interval = __set_swap_interval;
mHalPreviewWindow.nw.get_min_undequeued_buffer_count =
__get_min_undequeued_buffer_count;
}
OK，將__xxxx函數賦值給mHalPreviewWindow.nw中的函數指針。 ide
在Preview以前須要將ANativeWindow傳遞到HAL， 函數
/** Set the ANativeWindow to which preview frames are sent */
status_t setPreviewWindow(const sp<ANativeWindow>& buf)
{
ALOGV("%s(%s) buf %p", __FUNCTION__, mName.string(), buf.get());
if (mDevice->ops->set_preview_window) {
mPreviewWindow = buf;
mHalPreviewWindow.user = this;
ALOGV("%s &mHalPreviewWindow %p mHalPreviewWindow.user %p", __FUNCTION__,
&mHalPreviewWindow, mHalPreviewWindow.user);
return mDevice->ops->set_preview_window(mDevice,
buf.get() ? &mHalPreviewWindow.nw : 0);
}
return INVALID_OPERATION;
}
在HAL中就能夠使用這些函數對ANativeWindow進行操做，例如其中的一個函數實現__dequeue_buffer ui
此函數是從ANativeWindow隊列中獲取一個閒置buffer， this
@CameraHardwareInterface.h lua
#define anw(n) __to_anw(((struct camera_preview_window *)n)->user)
static int __dequeue_buffer(struct preview_stream_ops* w,
buffer_handle_t** buffer, int *stride)
{
int rc;
ANativeWindow *a = anw(w);
ANativeWindowBuffer* anb;
rc = a->dequeueBuffer(a, &anb);
if (!rc) {
*buffer = &anb->handle;
*stride = anb->stride;
}
return rc;
} 在HAL中，咱們能夠看到對display部分的初始化，初始視頻格式設置爲HAL_PIXEL_FORMAT_YCrCb_420_SP
ANativeWindowDisplayAdapter::ANativeWindowDisplayAdapter():mDisplayThread(NULL),
mDisplayState(ANativeWindowDisplayAdapter::DISPLAY_INIT),
mDisplayEnabled(false),
mBufferCount(0)
{
LOG_FUNCTION_NAME;
...
mPixelFormat = NULL;
mNativeWindowPixelFormat = HAL_PIXEL_FORMAT_YCrCb_420_SP;
} 以及改變pixelFormat的函數：
err = mANativeWindow->set_buffers_geometry(
mANativeWindow,
width,
height,
mNativeWindowPixelFormat); //NV21 此函數直接會直接回調到CameraHardwareInterface.h中的ANativeWindow的函數實現：
static int __set_buffers_geometry(struct preview_stream_ops* w,
int width, int height, int format)
{
ANativeWindow *a = anw(w);
return native_window_set_buffers_geometry(a,
width, height, format);
} 而native_window_set_buffers_geometry()是跨進程的函數調用，定義在system/core/include/system/window.h
/*
* native_window_set_buffers_geometry(..., int w, int h, int format)
* All buffers dequeued after this call will have the dimensions and format
* specified. A successful call to this function has the same effect as calling
* native_window_set_buffers_size and native_window_set_buffers_format.
*
* XXX: This function is deprecated. The native_window_set_buffers_dimensions
* and native_window_set_buffers_format functions should be used instead.
*/
static inline int native_window_set_buffers_geometry(
struct ANativeWindow* window,
int w, int h, int format)
{
return window->perform(window, NATIVE_WINDOW_SET_BUFFERS_GEOMETRY,
w, h, format);
} Struct ANativeWindow也定義在此文件中，ANativeWindow是OpenGL畫圖的一個接口，
Surface類繼 承了ANativeWindow類。ANativeWindow類是鏈接OpenGL和Android窗口系統的橋樑，即OpenGL須要經過 ANativeWindow類來間接地操做Android窗口系統。這種橋樑關係是經過EGL庫來創建的，全部以egl爲前綴的函數名均爲EGL庫提供的 接口，暫時知道這麼多。上面的函數是經過window->preform(,,,)實現的
/*
* hook used to perform various operations on the surface.
* (*perform)() is a generic mechanism to add functionality to
* ANativeWindow while keeping backward binary compatibility.
*
* DO NOT CALL THIS HOOK DIRECTLY. Instead, use the helper functions
* defined below.
*
* (*perform)() returns -ENOENT if the 'what' parameter is not supported
* by the surface's implementation.
*
* The valid operations are:
* NATIVE_WINDOW_SET_USAGE
* NATIVE_WINDOW_CONNECT (deprecated)
* NATIVE_WINDOW_DISCONNECT (deprecated)
* NATIVE_WINDOW_SET_CROP (private)
* NATIVE_WINDOW_SET_BUFFER_COUNT
* NATIVE_WINDOW_SET_BUFFERS_GEOMETRY (deprecated)
* NATIVE_WINDOW_SET_BUFFERS_TRANSFORM
* NATIVE_WINDOW_SET_BUFFERS_TIMESTAMP
* NATIVE_WINDOW_SET_BUFFERS_DIMENSIONS
* NATIVE_WINDOW_SET_BUFFERS_FORMAT
* NATIVE_WINDOW_SET_SCALING_MODE (private)
* NATIVE_WINDOW_LOCK (private)
* NATIVE_WINDOW_UNLOCK_AND_POST (private)
* NATIVE_WINDOW_API_CONNECT (private)
* NATIVE_WINDOW_API_DISCONNECT (private)
* NATIVE_WINDOW_SET_BUFFERS_USER_DIMENSIONS (private)
* NATIVE_WINDOW_SET_POST_TRANSFORM_CROP (private)
*
*/
int (*perform)(struct ANativeWindow* window,
int operation, ... );
定義了一個函數指針int (*perform)(struct ANativeWindow* window， int operation, ... ); spa
@./frameworks/native/libs/gui/SurfaceTextureClient.cpp .net
int SurfaceTextureClient::perform(int operation, va_list args)
{
int res = NO_ERROR;
switch (operation) {
case NATIVE_WINDOW_CONNECT:
// deprecated. must return NO_ERROR.
break;
case NATIVE_WINDOW_DISCONNECT:
// deprecated. must return NO_ERROR.
break;
case NATIVE_WINDOW_SET_USAGE:
res = dispatchSetUsage(args);
break;
case NATIVE_WINDOW_SET_CROP:
res = dispatchSetCrop(args);
break;
case NATIVE_WINDOW_SET_BUFFER_COUNT:
res = dispatchSetBufferCount(args);
break;
case NATIVE_WINDOW_SET_BUFFERS_GEOMETRY:
res = dispatchSetBuffersGeometry(args);
break;
case NATIVE_WINDOW_SET_BUFFERS_TRANSFORM:
res = dispatchSetBuffersTransform(args);
break;
case NATIVE_WINDOW_SET_BUFFERS_TIMESTAMP:
res = dispatchSetBuffersTimestamp(args);
break;
case NATIVE_WINDOW_SET_BUFFERS_DIMENSIONS:
res = dispatchSetBuffersDimensions(args);
break;
case NATIVE_WINDOW_SET_BUFFERS_USER_DIMENSIONS:
res = dispatchSetBuffersUserDimensions(args);
break;
case NATIVE_WINDOW_SET_BUFFERS_FORMAT:
res = dispatchSetBuffersFormat(args);
break;
case NATIVE_WINDOW_LOCK:
res = dispatchLock(args);
break;
case NATIVE_WINDOW_UNLOCK_AND_POST:
res = dispatchUnlockAndPost(args);
break;
case NATIVE_WINDOW_SET_SCALING_MODE:
res = dispatchSetScalingMode(args);
break;
case NATIVE_WINDOW_API_CONNECT:
res = dispatchConnect(args);
break;
case NATIVE_WINDOW_API_DISCONNECT:
res = dispatchDisconnect(args);
break;
default:
res = NAME_NOT_FOUND;
break;
}
return res;
}
int SurfaceTextureClient::dispatchSetBuffersGeometry(va_list args) {
int w = va_arg(args, int);
int h = va_arg(args, int);
int f = va_arg(args, int);
int err = setBuffersDimensions(w, h);
if (err != 0) {
return err;
}
return setBuffersFormat(f);
}
int SurfaceTextureClient::setBuffersFormat(int format)
{
ALOGV("SurfaceTextureClient::setBuffersFormat");
if (format<0)
return BAD_VALUE;
Mutex::Autolock lock(mMutex);
mReqFormat = format;
return NO_ERROR;
} 看不出來什麼。mReqFormat也沒有什麼條件進行判斷。再看另一個函數
int SurfaceTextureClient::dequeueBuffer(android_native_buffer_t** buffer) {
ATRACE_CALL();
ALOGV("SurfaceTextureClient::dequeueBuffer");
Mutex::Autolock lock(mMutex);
int buf = -1;
int reqW = mReqWidth ? mReqWidth : mUserWidth;
int reqH = mReqHeight ? mReqHeight : mUserHeight;
status_t result = mSurfaceTexture->dequeueBuffer(&buf, reqW, reqH,
mReqFormat, mReqUsage);
mSurfaceTexture是ISurfaceTexture類型，是SurfaceTexture服務client service結構中的client。
SurfaceTexture.cpp中
class BpSurfaceTexture : public BpInterface<ISurfaceTexture>
{
public:
virtual status_t dequeueBuffer(int *buf, uint32_t w, uint32_t h,
uint32_t format, uint32_t usage) {
Parcel data, reply;
data.writeInterfaceToken(ISurfaceTexture::getInterfaceDescriptor());
data.writeInt32(w);
data.writeInt32(h);
data.writeInt32(format);
data.writeInt32(usage);
status_t result = remote()->transact(DEQUEUE_BUFFER, data, &reply);
if (result != NO_ERROR) {
return result;
}
*buf = reply.readInt32();
result = reply.readInt32();
return result;
}
} 再看BnSurfaceTexture是如何實現DEQUEUE_BUFFER的
status_t BnSurfaceTexture::onTransact(
uint32_t code, const Parcel& data, Parcel* reply, uint32_t flags)
{
switch(code) {
case DEQUEUE_BUFFER: {
CHECK_INTERFACE(ISurfaceTexture, data, reply);
uint32_t w = data.readInt32();
uint32_t h = data.readInt32();
uint32_t format = data.readInt32();
uint32_t usage = data.readInt32();
int buf;
int result = dequeueBuffer(&buf, w, h, format, usage);
reply->writeInt32(buf);
reply->writeInt32(result);
return NO_ERROR;
} break;
}
dequeueBuffer在BnSurfaceTexture中沒有實現，子類BufferQueue中(@BufferQueue.h)
class BufferQueue : public BnSurfaceTexture {
public:
// dequeueBuffer gets the next buffer slot index for the client to use. If a
// buffer slot is available then that slot index is written to the location
// pointed to by the buf argument and a status of OK is returned. If no
// slot is available then a status of -EBUSY is returned and buf is
// unmodified.
// The width and height parameters must be no greater than the minimum of
// GL_MAX_VIEWPORT_DIMS and GL_MAX_TEXTURE_SIZE (see: glGetIntegerv).
// An error due to invalid dimensions might not be reported until
// updateTexImage() is called.
virtual status_t dequeueBuffer(int *buf, uint32_t width, uint32_t height,
uint32_t format, uint32_t usage);
}
status_t BufferQueue::dequeueBuffer(int *outBuf, uint32_t w, uint32_t h,
uint32_t format, uint32_t usage) {
ATRACE_CALL();
ST_LOGV("dequeueBuffer: w=%d h=%d fmt=%#x usage=%#x", w, h, format, usage);
if ((w && !h) || (!w && h)) {
ST_LOGE("dequeueBuffer: invalid size: w=%u, h=%u", w, h);
return BAD_VALUE;
}
status_t returnFlags(OK);
EGLDisplay dpy = EGL_NO_DISPLAY;
EGLSyncKHR fence = EGL_NO_SYNC_KHR;
{ // Scope for the lock
Mutex::Autolock lock(mMutex);
if (format == 0) {
format = mDefaultBufferFormat;
}
// turn on usage bits the consumer requested
usage |= mConsumerUsageBits;
int found = -1;
int foundSync = -1;
int dequeuedCount = 0;
bool tryAgain = true;
while (tryAgain) {
if (mAbandoned) {
ST_LOGE("dequeueBuffer: SurfaceTexture has been abandoned!");
return NO_INIT;
}
// We need to wait for the FIFO to drain if the number of buffer
// needs to change.
//
// The condition "number of buffers needs to change" is true if
// - the client doesn't care about how many buffers there are
// - AND the actual number of buffer is different from what was
// set in the last setBufferCountServer()
// - OR -
// setBufferCountServer() was set to a value incompatible with
// the synchronization mode (for instance because the sync mode
// changed since)
//
// As long as this condition is true AND the FIFO is not empty, we
// wait on mDequeueCondition.
const int minBufferCountNeeded = mSynchronousMode ?
mMinSyncBufferSlots : mMinAsyncBufferSlots;
const bool numberOfBuffersNeedsToChange = !mClientBufferCount &&
((mServerBufferCount != mBufferCount) ||
(mServerBufferCount < minBufferCountNeeded));
if (!mQueue.isEmpty() && numberOfBuffersNeedsToChange) {
// wait for the FIFO to drain
mDequeueCondition.wait(mMutex);
// NOTE: we continue here because we need to reevaluate our
// whole state (eg: we could be abandoned or disconnected)
continue;
}
if (numberOfBuffersNeedsToChange) {
// here we're guaranteed that mQueue is empty
freeAllBuffersLocked();
mBufferCount = mServerBufferCount;
if (mBufferCount < minBufferCountNeeded)
mBufferCount = minBufferCountNeeded;
mBufferHasBeenQueued = false;
returnFlags |= ISurfaceTexture::RELEASE_ALL_BUFFERS;
}
// look for a free buffer to give to the client
found = INVALID_BUFFER_SLOT;
foundSync = INVALID_BUFFER_SLOT;
dequeuedCount = 0;
for (int i = 0; i < mBufferCount; i++) {
const int state = mSlots[i].mBufferState;
if (state == BufferSlot::DEQUEUED) {
dequeuedCount++;
}
// this logic used to be if (FLAG_ALLOW_DEQUEUE_CURRENT_BUFFER)
// but dequeuing the current buffer is disabled.
if (false) {
// This functionality has been temporarily removed so
// BufferQueue and SurfaceTexture can be refactored into
// separate objects
} else {
if (state == BufferSlot::FREE) {
/* We return the oldest of the free buffers to avoid
* stalling the producer if possible. This is because
* the consumer may still have pending reads of the
* buffers in flight.
*/
bool isOlder = mSlots[i].mFrameNumber <
mSlots[found].mFrameNumber;
if (found < 0 || isOlder) {
foundSync = i;
found = i;
}
}
}
}
// clients are not allowed to dequeue more than one buffer
// if they didn't set a buffer count.
if (!mClientBufferCount && dequeuedCount) {
ST_LOGE("dequeueBuffer: can't dequeue multiple buffers without "
"setting the buffer count");
return -EINVAL;
}
// See whether a buffer has been queued since the last
// setBufferCount so we know whether to perform the
// mMinUndequeuedBuffers check below.
if (mBufferHasBeenQueued) {
// make sure the client is not trying to dequeue more buffers
// than allowed.
const int avail = mBufferCount - (dequeuedCount+1);
if (avail < (mMinUndequeuedBuffers-int(mSynchronousMode))) {
ST_LOGE("dequeueBuffer: mMinUndequeuedBuffers=%d exceeded "
"(dequeued=%d)",
mMinUndequeuedBuffers-int(mSynchronousMode),
dequeuedCount);
return -EBUSY;
}
}
// if no buffer is found, wait for a buffer to be released
tryAgain = found == INVALID_BUFFER_SLOT;
if (tryAgain) {
mDequeueCondition.wait(mMutex);
}
}
if (found == INVALID_BUFFER_SLOT) {
// This should not happen.
ST_LOGE("dequeueBuffer: no available buffer slots");
return -EBUSY;
}
const int buf = found;
*outBuf = found;
ATRACE_BUFFER_INDEX(buf);
const bool useDefaultSize = !w && !h;
if (useDefaultSize) {
// use the default size
w = mDefaultWidth;
h = mDefaultHeight;
}
const bool updateFormat = (format != 0);
if (!updateFormat) {
// keep the current (or default) format
format = mPixelFormat;
}
// buffer is now in DEQUEUED (but can also be current at the same time,
// if we're in synchronous mode)
mSlots[buf].mBufferState = BufferSlot::DEQUEUED;
const sp<GraphicBuffer>& buffer(mSlots[buf].mGraphicBuffer);
if ((buffer == NULL) ||
(uint32_t(buffer->width) != w) ||
(uint32_t(buffer->height) != h) ||
(uint32_t(buffer->format) != format) ||
((uint32_t(buffer->usage) & usage) != usage))
{
status_t error;
sp<GraphicBuffer> graphicBuffer(
mGraphicBufferAlloc->createGraphicBuffer(
w, h, format, usage, &error));
if (graphicBuffer == 0) {
ST_LOGE("dequeueBuffer: SurfaceComposer::createGraphicBuffer "
"failed");
return error;
}
if (updateFormat) {
mPixelFormat = format;
}
mSlots[buf].mAcquireCalled = false;
mSlots[buf].mGraphicBuffer = graphicBuffer;
mSlots[buf].mRequestBufferCalled = false;
mSlots[buf].mFence = EGL_NO_SYNC_KHR;
mSlots[buf].mEglDisplay = EGL_NO_DISPLAY;
returnFlags |= ISurfaceTexture::BUFFER_NEEDS_REALLOCATION;
}
dpy = mSlots[buf].mEglDisplay;
fence = mSlots[buf].mFence;
mSlots[buf].mFence = EGL_NO_SYNC_KHR;
mDequeueUsage = usage;
} // end lock scope
if (fence != EGL_NO_SYNC_KHR) {
EGLint result = eglClientWaitSyncKHR(dpy, fence, 0, 1000000000);
// If something goes wrong, log the error, but return the buffer without
// synchronizing access to it. It's too late at this point to abort the
// dequeue operation.
if (result == EGL_FALSE) {
ST_LOGE("dequeueBuffer: error waiting for fence: %#x", eglGetError());
} else if (result == EGL_TIMEOUT_EXPIRED_KHR) {
ST_LOGE("dequeueBuffer: timeout waiting for fence");
}
eglDestroySyncKHR(dpy, fence);
}
ST_LOGV("dequeueBuffer: returning slot=%d buf=%p flags=%#x", *outBuf,
mSlots[*outBuf].mGraphicBuffer->handle, returnFlags);
return returnFlags;
}
BufferQueue::dequeueBuffer 上面的函數太長，若是當前的format跟參數中的format不一致，則須要從新申請，
sp<GraphicBuffer> graphicBuffer(
mGraphicBufferAlloc->createGraphicBuffer(
w, h, format, usage, &error));
// mGraphicBufferAlloc is the connection to SurfaceFlinger that is used to
// allocate new GraphicBuffer objects.
sp<IGraphicBufferAlloc> mGraphicBufferAlloc;
到surfaceFliger了@9 :SurfaceFlinger.cpp
sp<GraphicBuffer> GraphicBufferAlloc::createGraphicBuffer(uint32_t w, uint32_t h,
PixelFormat format, uint32_t usage, status_t* error) {
sp<GraphicBuffer> graphicBuffer(new GraphicBuffer(w, h, format, usage));
status_t err = graphicBuffer->initCheck();
*error = err;
if (err != 0 || graphicBuffer->handle == 0) {
if (err == NO_MEMORY) {
GraphicBuffer::dumpAllocationsToSystemLog();
}
ALOGE("GraphicBufferAlloc::createGraphicBuffer(w=%d, h=%d) "
"failed (%s), handle=%p",
w, h, strerror(-err), graphicBuffer->handle);
return 0;
}
return graphicBuffer;
}
GraphicBuffer定義在native/include/ui/GraphicBuffer.h
構造函數中指定format的類型爲PixelFormat
namespace android {
enum {
//
// these constants need to match those
// in graphics/PixelFormat.java & pixelflinger/format.h
//
PIXEL_FORMAT_UNKNOWN = 0,
PIXEL_FORMAT_NONE = 0,
// logical pixel formats used by the SurfaceFlinger -----------------------
PIXEL_FORMAT_CUSTOM = -4,
// Custom pixel-format described by a PixelFormatInfo structure
PIXEL_FORMAT_TRANSLUCENT = -3,
// System chooses a format that supports translucency (many alpha bits)
PIXEL_FORMAT_TRANSPARENT = -2,
// System chooses a format that supports transparency
// (at least 1 alpha bit)
PIXEL_FORMAT_OPAQUE = -1,
// System chooses an opaque format (no alpha bits required)
// real pixel formats supported for rendering -----------------------------
PIXEL_FORMAT_RGBA_8888 = HAL_PIXEL_FORMAT_RGBA_8888, // 4x8-bit RGBA
PIXEL_FORMAT_RGBX_8888 = HAL_PIXEL_FORMAT_RGBX_8888, // 4x8-bit RGB0
PIXEL_FORMAT_RGB_888 = HAL_PIXEL_FORMAT_RGB_888, // 3x8-bit RGB
PIXEL_FORMAT_RGB_565 = HAL_PIXEL_FORMAT_RGB_565, // 16-bit RGB
PIXEL_FORMAT_BGRA_8888 = HAL_PIXEL_FORMAT_BGRA_8888, // 4x8-bit BGRA
PIXEL_FORMAT_RGBA_5551 = HAL_PIXEL_FORMAT_RGBA_5551, // 16-bit ARGB
PIXEL_FORMAT_RGBA_4444 = HAL_PIXEL_FORMAT_RGBA_4444, // 16-bit ARGB
PIXEL_FORMAT_A_8 = 8, // 8-bit A
};
typedef int32_t PixelFormat;
struct PixelFormatInfo {
enum {
INDEX_ALPHA = 0,
INDEX_RED = 1,
INDEX_GREEN = 2,
INDEX_BLUE = 3
};
enum { // components
ALPHA = 1,
RGB = 2,
RGBA = 3,
L = 4,
LA = 5,
OTHER = 0xFF
};
struct szinfo {
uint8_t h;
uint8_t l;
};
inline PixelFormatInfo() : version(sizeof(PixelFormatInfo)) { }
size_t getScanlineSize(unsigned int width) const;
size_t getSize(size_t ci) const {
return (ci <= 3) ? (cinfo[ci].h - cinfo[ci].l) : 0;
}
size_t version;
PixelFormat format;
size_t bytesPerPixel;
size_t bitsPerPixel;
union {
szinfo cinfo[4];
struct {
uint8_t h_alpha;
uint8_t l_alpha;
uint8_t h_red;
uint8_t l_red;
uint8_t h_green;
uint8_t l_green;
uint8_t h_blue;
uint8_t l_blue;
};
};
uint8_t components;
uint8_t reserved0[3];
uint32_t reserved1;
};
感受有點問題，這裏的PixelFormat跟下面的定義不一致，好像是對PixelFormat的擴展。
格式HAL_PIXEL_FORMAT_YCrCb_420_SP的定義在./system/core/include/system/graphics.h
enum {
HAL_PIXEL_FORMAT_RGBA_8888 = 1,
HAL_PIXEL_FORMAT_RGBX_8888 = 2,
HAL_PIXEL_FORMAT_RGB_888 = 3,
HAL_PIXEL_FORMAT_RGB_565 = 4,
HAL_PIXEL_FORMAT_BGRA_8888 = 5,
HAL_PIXEL_FORMAT_RGBA_5551 = 6,
HAL_PIXEL_FORMAT_RGBA_4444 = 7,
/* 0x8 - 0xFF range unavailable */
/*
* 0x100 - 0x1FF
*
* This range is reserved for pixel formats that are specific to the HAL
* implementation. Implementations can use any value in this range to
* communicate video pixel formats between their HAL modules. These formats
* must not have an alpha channel. Additionally, an EGLimage created from a
* gralloc buffer of one of these formats must be supported for use with the
* GL_OES_EGL_image_external OpenGL ES extension.
*/
/*
* Android YUV format:
*
* This format is exposed outside of the HAL to software decoders and
* applications. EGLImageKHR must support it in conjunction with the
* OES_EGL_image_external extension.
*
* YV12 is a 4:2:0 YCrCb planar format comprised of a WxH Y plane followed
* by (W/2) x (H/2) Cr and Cb planes.
*
* This format assumes
* - an even width
* - an even height
* - a horizontal stride multiple of 16 pixels
* - a vertical stride equal to the height
*
* y_size = stride * height
* c_stride = ALIGN(stride/2, 16)
* c_size = c_stride * height/2
* size = y_size + c_size * 2
* cr_offset = y_size
* cb_offset = y_size + c_size
*
*/
HAL_PIXEL_FORMAT_YV12 = 0x32315659, // YCrCb 4:2:0 Planar
/*
* Android RAW sensor format:
*
* This format is exposed outside of the HAL to applications.
*
* RAW_SENSOR is a single-channel 16-bit format, typically representing raw
* Bayer-pattern images from an image sensor, with minimal processing.
*
* The exact pixel layout of the data in the buffer is sensor-dependent, and
* needs to be queried from the camera device.
*
* Generally, not all 16 bits are used; more common values are 10 or 12
* bits. All parameters to interpret the raw data (black and white points,
* color space, etc) must be queried from the camera device.
*
* This format assumes
* - an even width
* - an even height
* - a horizontal stride multiple of 16 pixels (32 bytes).
*/
HAL_PIXEL_FORMAT_RAW_SENSOR = 0x20,
/* Legacy formats (deprecated), used by ImageFormat.java */
HAL_PIXEL_FORMAT_YCbCr_422_SP = 0x10, // NV16
HAL_PIXEL_FORMAT_YCrCb_420_SP = 0x11, // NV21
HAL_PIXEL_FORMAT_YCbCr_422_I = 0x14, // YUY2
};
相關文章
- 1. 【Android Camera】之 Preview
- 2. Android camera: how to show preview from camera using Camera2 API
- 3. Android Camera:總結
- 4. preview
- 5. Android 10 Camera -- Camera HAL3
- 6. Android 使Camera預覽清晰，循環自動對焦處理
- 7. Android Camera簡單整理(一)-Camera Android架構(基於Q)
- 8. Android Camera 系列（二）控制Camera
- 9. android camera Parameters
- 10. Android中*_handle_t/ANativeWindowBuffer/ANativeWindow/GraphicBuffer/Surface的關係
- 更多相關文章...
- • 錯誤處理 - RUST 教程
- • C# 異常處理 - C#教程
- • Docker 清理命令
- • ☆技術問答集錦（13）Java Instrument原理
相關標籤/搜索
每日一句
-
每一个你不满意的现在，都有一个你没有努力的曾经。
歡迎關注本站公眾號,獲取更多信息
相關文章
- 1. 【Android Camera】之 Preview
- 2. Android camera: how to show preview from camera using Camera2 API
- 3. Android Camera:總結
- 4. preview
- 5. Android 10 Camera -- Camera HAL3
- 6. Android 使Camera預覽清晰，循環自動對焦處理
- 7. Android Camera簡單整理(一)-Camera Android架構(基於Q)
- 8. Android Camera 系列（二）控制Camera
- 9. android camera Parameters
- 10. Android中*_handle_t/ANativeWindowBuffer/ANativeWindow/GraphicBuffer/Surface的關係