\u60f3\u8981\u77e5\u9053Driver\u56de\u6765\u7684\u6570\u636e\u662f\u5982\u4f55\u663e\u793a\u51fa\u6765\u7684\u5417\uff1f
\n\u8fd9\u4e2a\u5de5\u4f5c\u662f\u5728\u54ea\u4e00\u5c42\u505a\u7684\uff1f<\/p>\n
\u8ddf\u8e2a\u4ee3\u7801\u5c31\u53ef\u4ee5\u7406\u6e05\u695a\u8fd9\u4e00\u8fc7\u7a0b\uff0c\u8fd9\u91cc\u4ee3\u7801\u7248\u672c\u662fJelly Bean\u3002<\/p>\n
CameraHardwareInterface\u521d\u59cb\u5316\u7684\u65f6\u5019\u4f1a\u521d\u59cb\u5316\u597dwindow\u6709\u5173\u7684\u6570\u636e<\/p>\n
struct camera_preview_window {\r\n struct preview_stream_ops nw;\r\n void *user;\r\n};\r\n\r\nstruct camera_preview_window mHalPreviewWindow;\r\n\r\nstatus_t initialize(hw_module_t *module)\r\n{\r\n ALOGI("Opening camera %s", mName.string());\r\n int rc = module->methods->open(module, mName.string(),\r\n (hw_device_t **)&mDevice);\r\n if (rc != OK) {\r\n ALOGE("Could not open camera %s: %d", mName.string(), rc);\r\n return rc;\r\n }\r\n initHalPreviewWindow();\r\n return rc;\r\n}\r\n\r\nvoid initHalPreviewWindow()\r\n{\r\n mHalPreviewWindow.nw.cancel_buffer = __cancel_buffer;\r\n mHalPreviewWindow.nw.lock_buffer = __lock_buffer;\r\n mHalPreviewWindow.nw.dequeue_buffer = __dequeue_buffer;\r\n mHalPreviewWindow.nw.enqueue_buffer = __enqueue_buffer;\r\n mHalPreviewWindow.nw.set_buffer_count = __set_buffer_count;\r\n mHalPreviewWindow.nw.set_buffers_geometry = __set_buffers_geometry;\r\n mHalPreviewWindow.nw.set_crop = __set_crop;\r\n mHalPreviewWindow.nw.set_timestamp = __set_timestamp;\r\n mHalPreviewWindow.nw.set_usage = __set_usage;\r\n mHalPreviewWindow.nw.set_swap_interval = __set_swap_interval;\r\n\r\n mHalPreviewWindow.nw.get_min_undequeued_buffer_count =\r\n __get_min_undequeued_buffer_count;\r\n}\r\n\r\nstatic int __dequeue_buffer(struct preview_stream_ops* w,\r\n buffer_handle_t** buffer, int *stride)\r\n{\r\n int rc;\r\n ANativeWindow *a = anw(w);\r\n ANativeWindowBuffer* anb;\r\n rc = native_window_dequeue_buffer_and_wait(a, &anb);\r\n if (!rc) {\r\n *buffer = &anb->handle;\r\n *stride = anb->stride;\r\n }\r\n return rc;\r\n}\r\n\r\nstatic int __enqueue_buffer(struct preview_stream_ops* w,\r\n buffer_handle_t* buffer)\r\n{\r\n ANativeWindow *a = anw(w);\r\n return a->queueBuffer(a,\r\n container_of(buffer, ANativeWindowBuffer, handle), -1);\r\n}<\/pre>\n\u7ee7\u800c\u5728Vendor\u7684HAL\u5f53\u4e2d\uff0c\u8fd9\u91cc\u4ee5TI\u4e3a\u4f8b\u5b50<\/p>\n
\/**\r\n @brief Sets ANativeWindow object.\r\n\r\n Preview buffers provided to CameraHal via this object. DisplayAdapter will be interfacing with it\r\n to render buffers to display.\r\n\r\n @param[in] window The ANativeWindow object created by Surface flinger\r\n @return NO_ERROR If the ANativeWindow object passes validation criteria\r\n @todo Define validation criteria for ANativeWindow object. Define error codes for scenarios\r\n\r\n *\/\r\nstatus_t CameraHal::setPreviewWindow(struct preview_stream_ops *window)\r\n{\r\n status_t ret = NO_ERROR;\r\n CameraAdapter::BuffersDescriptor desc;\r\n\r\n LOG_FUNCTION_NAME;\r\n mSetPreviewWindowCalled = true;\r\n\r\n \/\/\/If the Camera service passes a null window, we destroy existing window and free the DisplayAdapter\r\n if(!window)\r\n {\r\n if(mDisplayAdapter.get() != NULL)\r\n {\r\n \/\/\/NULL window passed, destroy the display adapter if present\r\n CAMHAL_LOGDA("NULL window passed, destroying display adapter");\r\n mDisplayAdapter.clear();\r\n \/\/\/@remarks If there was a window previously existing, we usually expect another valid window to be passed by the client\r\n \/\/\/@remarks so, we will wait until it passes a valid window to begin the preview again\r\n mSetPreviewWindowCalled = false;\r\n }\r\n CAMHAL_LOGDA("NULL ANativeWindow passed to setPreviewWindow");\r\n return NO_ERROR;\r\n }else if(mDisplayAdapter.get() == NULL)\r\n {\r\n \/\/ Need to create the display adapter since it has not been created\r\n \/\/ Create display adapter\r\n mDisplayAdapter = new ANativeWindowDisplayAdapter();\r\n\r\n ...\r\n\r\n \/\/ DisplayAdapter needs to know where to get the CameraFrames from inorder to display\r\n \/\/ Since CameraAdapter is the one that provides the frames, set it as the frame provider for DisplayAdapter\r\n mDisplayAdapter->setFrameProvider(mCameraAdapter);\r\n\r\n ...\r\n\r\n \/\/ Update the display adapter with the new window that is passed from CameraService\r\n \/\/ \u8fd9\u91cc\u7684window(ANativeWindowDisplayAdapter::mANativeWindow)\u5c31\u662fCameraHardwareInterface::mHalPreviewWindow::nw\r\n ret = mDisplayAdapter->setPreviewWindow(window);\r\n if(ret!=NO_ERROR)\r\n {\r\n CAMHAL_LOGEB("DisplayAdapter setPreviewWindow returned error %d", ret);\r\n }\r\n\r\n if(mPreviewStartInProgress)\r\n {\r\n CAMHAL_LOGDA("setPreviewWindow called when preview running");\r\n \/\/ Start the preview since the window is now available\r\n ret = startPreview();\r\n }\r\n } else {\r\n \/\/ Update the display adapter with the new window that is passed from CameraService\r\n ret = mDisplayAdapter->setPreviewWindow(window);\r\n if ( (NO_ERROR == ret) && previewEnabled() ) {\r\n restartPreview();\r\n } else if (ret == ALREADY_EXISTS) {\r\n \/\/ ALREADY_EXISTS should be treated as a noop in this case\r\n ret = NO_ERROR;\r\n }\r\n }\r\n LOG_FUNCTION_NAME_EXIT;\r\n\r\n return ret;\r\n\r\n}<\/pre>\n\u6ce8\u610f\u770bsetPreviewWindow\u4e4b\u524d\u6211\u52a0\u7684\u4e00\u884c\u4e2d\u6587\u6ce8\u91ca<\/p>\n
\u5728TI\u7684HAL\u5f53\u4e2d\u6709\u53bb\u505a\u5305\u4e00\u4e9badaper\u51fa\u6765\uff0c\u5b9e\u9645\u5c31\u662f\u53d6\u6570\u636e\u7684(\u6bd4\u5982V4L2CameraAdapter\uff0c\u4e5f\u5c31\u662fCameraAdapter)\uff0c\u548c\u6570\u636e\u53d1\u5176\u4ed6\u5730\u65b9(\u6bd4\u5982ANativeWindowDisplayAdapter\uff0c\u4e5f\u5c31\u662fDisplayAdapter)\u53bb\u7528\u7684\u3002<\/p>\n
\u5728TI\u7684HW\u5f53\u4e2d\uff0c\u6709previewThread(\u4f4d\u4e8eV4LCameraAdapter\u5f53\u4e2d)\uff0cpreviewThread\u4f1a\u4e0d\u65ad\u7684\u901a\u8fc7IOCTL\u4eceV4L2\u83b7\u53d6frame<\/p>\n
int V4LCameraAdapter::previewThread()\r\n{\r\n status_t ret = NO_ERROR;\r\n int width, height;\r\n CameraFrame frame;\r\n\r\n if (mPreviewing)\r\n {\r\n int index = 0;\r\n char *fp = this->GetFrame(index);\r\n\r\n uint8_t* ptr = (uint8_t*) mPreviewBufs.keyAt(index);\r\n\r\n int width, height;\r\n uint16_t* dest = (uint16_t*)ptr;\r\n uint16_t* src = (uint16_t*) fp;\r\n mParams.getPreviewSize(&width, &height);\r\n\r\n ...\r\n\r\n mParams.getPreviewSize(&width, &height);\r\n frame.mFrameType = CameraFrame::PREVIEW_FRAME_SYNC;\r\n frame.mBuffer = ptr;\r\n\r\n ...\r\n\r\n ret = sendFrameToSubscribers(&frame);\r\n\r\n }\r\n\r\n return ret;\r\n}\r\n\r\nchar * V4LCameraAdapter::GetFrame(int &index)\r\n{\r\n int ret;\r\n\r\n mVideoInfo->buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;\r\n mVideoInfo->buf.memory = V4L2_MEMORY_MMAP;\r\n\r\n \/* DQ *\/\r\n ret = ioctl(mCameraHandle, VIDIOC_DQBUF, &mVideoInfo->buf);\r\n if (ret < 0) {\r\n CAMHAL_LOGEA("GetFrame: VIDIOC_DQBUF Failed");\r\n return NULL;\r\n }\r\n nDequeued++;\r\n\r\n index = mVideoInfo->buf.index;\r\n\r\n return (char *)mVideoInfo->mem[mVideoInfo->buf.index];\r\n}\r\n\r\n\r\n\r\nclass CameraFrame\r\n{\r\n public:\r\n\r\n enum FrameType\r\n {\r\n PREVIEW_FRAME_SYNC = 0x1, \/\/\/SYNC implies that the frame needs to be explicitly returned after consuming in order to be filled by camera again\r\n PREVIEW_FRAME = 0x2 , \/\/\/Preview frame includes viewfinder and snapshot frames\r\n IMAGE_FRAME_SYNC = 0x4, \/\/\/Image Frame is the image capture output frame\r\n IMAGE_FRAME = 0x8,\r\n VIDEO_FRAME_SYNC = 0x10, \/\/\/Timestamp will be updated for these frames\r\n VIDEO_FRAME = 0x20,\r\n FRAME_DATA_SYNC = 0x40, \/\/\/Any extra data assosicated with the frame. Always synced with the frame\r\n FRAME_DATA= 0x80,\r\n RAW_FRAME = 0x100,\r\n SNAPSHOT_FRAME = 0x200,\r\n ALL_FRAMES = 0xFFFF \/\/\/Maximum of 16 frame types supported\r\n };\r\n\r\n enum FrameQuirks\r\n {\r\n ENCODE_RAW_YUV422I_TO_JPEG = 0x1 << 0,\r\n HAS_EXIF_DATA = 0x1 << 1,\r\n };\r\n\r\n \/\/default contrustor\r\n CameraFrame():\r\n ...\r\n {\r\n ...\r\n }\r\n\r\n \/\/copy constructor\r\n CameraFrame(const CameraFrame &frame) :\r\n ...\r\n {\r\n ...\r\n }\r\n\r\n void *mCookie;\r\n void *mCookie2;\r\n void *mBuffer;\r\n int mFrameType;\r\n nsecs_t mTimestamp;\r\n unsigned int mWidth, mHeight;\r\n uint32_t mOffset;\r\n unsigned int mAlignment;\r\n int mFd;\r\n size_t mLength;\r\n unsigned mFrameMask;\r\n unsigned int mQuirks;\r\n unsigned int mYuv[2];\r\n \/\/\/@todo add other member vars like stride etc\r\n};[\/code]\r\n\u5bf9\u4e8eANativeWindowDisplayAdapter\uff0c\u5b83\u6709\u7ed9\u81ea\u5df1\u914d\u7f6e\u4e00\u4e2aFrameProvider\uff0c\u5b9e\u9645\u5c31\u662f\u4f1a\u53bb\u6ce8\u518c\u4e00\u79cdcallback\uff0c\u5f53\u4ecedriver\u56de\u6765\u6570\u636e\u7684\u65f6\u5019\u4f1a\u53bb\u901a\u77e5\u5bf9\u5e94\u7684callback\uff0c\u5f53\u7136\u8fd9\u4e2a\u65f6\u5019\u8fd8\u6ca1\u6709\u771f\u6b63\u7684\u53bb\u6ce8\u518c\r\n[code lang="java"]int ANativeWindowDisplayAdapter::setFrameProvider(FrameNotifier *frameProvider)\r\n{\r\n LOG_FUNCTION_NAME;\r\n\r\n \/\/ Check for NULL pointer\r\n if ( !frameProvider ) {\r\n CAMHAL_LOGEA("NULL passed for frame provider");\r\n LOG_FUNCTION_NAME_EXIT;\r\n return BAD_VALUE;\r\n }\r\n\r\n \/\/Release any previous frame providers\r\n if ( NULL != mFrameProvider ) {\r\n delete mFrameProvider;\r\n }\r\n\r\n \/** Dont do anything here, Just save the pointer for use when display is\r\n actually enabled or disabled\r\n *\/\r\n mFrameProvider = new FrameProvider(frameProvider, this, frameCallbackRelay);\r\n\r\n LOG_FUNCTION_NAME_EXIT;\r\n\r\n return NO_ERROR;\r\n}[\/code]\r\n\u5e76\u4e14\u6211\u4eec\u5728\u5f00\u59cbstart preview\u7684\u65f6\u5019\u4f1a\u53bb\u6ce8\u518c\u8fd9\u4e2acallback\uff0c\u5f53\u7136\u540c\u65f6\u5728start preview\u7684\u65f6\u5019\u6211\u4eec\u4e5f\u4f1a\u53bb\u5206\u914d\u4e00\u5757buffer\uff0c\u8fd9\u6837driver\u56de\u6765\u7684\u6570\u636e\u624d\u6709\u5730\u65b9\u653e\uff0c\u7533\u8bf7buffer\u5982\u4e0b\r\nCameraHal::allocateBuffer(...) __dequeue_buffer\r\n\r\n\u4e0b\u9762\u662f\u542f\u52a8living preview\uff0c\u6ce8\u518ccallback\r\n[code lang="java"]int ANativeWindowDisplayAdapter::enableDisplay(int width, int height, struct timeval *refTime, S3DParameters *s3dParams)\r\n{\r\n Semaphore sem;\r\n TIUTILS::Message msg;\r\n\r\n LOG_FUNCTION_NAME;\r\n\r\n if ( mDisplayEnabled )\r\n {\r\n CAMHAL_LOGDA("Display is already enabled");\r\n LOG_FUNCTION_NAME_EXIT;\r\n\r\n return NO_ERROR;\r\n }\r\n\r\n#if 0 \/\/TODO: s3d is not part of bringup...will reenable\r\n if (s3dParams)\r\n mOverlay->set_s3d_params(s3dParams->mode, s3dParams->framePacking,\r\n s3dParams->order, s3dParams->subSampling);\r\n#endif\r\n\r\n#if PPM_INSTRUMENTATION || PPM_INSTRUMENTATION_ABS\r\n\r\n if ( NULL != refTime )\r\n {\r\n Mutex::Autolock lock(mLock);\r\n memcpy(&mStandbyToShot, refTime, sizeof(struct timeval));\r\n mMeasureStandby = true;\r\n }\r\n\r\n#endif\r\n\r\n \/\/Send START_DISPLAY COMMAND to display thread. Display thread will start and then wait for a message\r\n sem.Create();\r\n msg.command = DisplayThread::DISPLAY_START;\r\n\r\n \/\/ Send the semaphore to signal once the command is completed\r\n msg.arg1 = &sem;\r\n\r\n \/\/\/Post the message to display thread\r\n mDisplayThread->msgQ().put(&msg);\r\n\r\n \/\/\/Wait for the ACK - implies that the thread is now started and waiting for frames\r\n sem.Wait();\r\n\r\n \/\/ Register with the frame provider for frames\r\n mFrameProvider->enableFrameNotification(CameraFrame::PREVIEW_FRAME_SYNC);\r\n\r\n mDisplayEnabled = true;\r\n mPreviewWidth = width;\r\n mPreviewHeight = height;\r\n\r\n CAMHAL_LOGVB("mPreviewWidth = %d mPreviewHeight = %d", mPreviewWidth, mPreviewHeight);\r\n\r\n LOG_FUNCTION_NAME_EXIT;\r\n\r\n return NO_ERROR;\r\n}\r\n\r\n\r\n\r\nint FrameProvider::enableFrameNotification(int32_t frameTypes)\r\n{\r\n LOG_FUNCTION_NAME;\r\n status_t ret = NO_ERROR;\r\n\r\n \/\/\/Enable the frame notification to CameraAdapter (which implements FrameNotifier interface)\r\n mFrameNotifier->enableMsgType(frameTypes<<MessageNotifier::FRAME_BIT_FIELD_POSITION\r\n , mFrameCallback\r\n , NULL\r\n , mCookie\r\n );\r\n\r\n \/\/ \u628aframeCallbackRelay\u8fd9\u4e2acallback\u6dfb\u52a0\u5230BaseCameraAdapter::mFrameSubscribers\u5f53\u4e2d\r\n \/\/ \u8be6\u89c1 preview_stream_ops_t* mANativeWindow; \u4ee5\u53ca ANativeWindowDisplayAdapter::PostFrame(...)\r\n \/\/ __enqueue_buffer\r\n \/\/ \u6700\u7ec8\u4f1a\u628a\u6570\u636e\u66f4\u65b0\u5230CameraHardwareInterface\u7684sp<ANativeWindow> mPreviewWindow;\r\n \/\/ \u8fd9\u6837\u6bcf\u8fc7\u6765\u4e00\u4e2aframe\uff0c\u4e5f\u5c31\u662f\u53bb\u66f4\u65b0\u6211\u4eec\u770b\u5230\u7684preview\u6570\u636e\r\n\r\n LOG_FUNCTION_NAME_EXIT;\r\n return ret;\r\n}<\/pre>\n\u89c1\u4e0a\u9762\u4ee3\u7801\u4e2d\u5d4c\u7684\u4e2d\u6587\u6ce8\u91ca\uff0c\u8fd9\u662f\u6211\u52a0\u7684\u3002<\/p>\n
\u53e6\u5916displayThread(\u4f4d\u4e8eANativeWindowDisplayAdapter\u5f53\u4e2d)\uff0cdisplayThread\u4f1a\u542c\u4e00\u4e9b\u4eceCamera HAL\u6765\u7684\u6d88\u606f\uff0c\u7136\u540e\u6267\u884c\uff0c\u8fd9\u4e2a\u4e0d\u662f\u5f88\u590d\u6742\u3002<\/p>\n
\u4e5f\u5c31\u662f\u8bf4\u6570\u636e\u662f\u600e\u4e48\u8d34\u5230view\u4e0a\u53bb\uff0c\u8fd9\u662fHAL\u8fd9\u5c42\u505a\u6389\u7684\uff0c\u867d\u7136\u53ea\u662f\u4e00\u4e2a\u8c03\u7528ANativeWindow\u7684\u8fc7\u7a0b\uff01<\/p>\n
\u8fd9\u53ea\u662f\u4e00\u4e2a\u7c97\u7cd9\u7684\u8fc7\u7a0b\uff0c\u518d\u6df1\u5c42\u7ec6\u8282\u7684\u6211\u4eec\u6682\u65f6\u4e0d\u7814\u7a76\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u60f3\u8981\u77e5\u9053Driver\u56de\u6765\u7684\u6570\u636e\u662f\u5982\u4f55\u663e\u793a\u51fa\u6765\u7684\u5417\uff1f \u8fd9\u4e2a\u5de5\u4f5c\u662f\u5728\u54ea\u4e00\u5c42\u505a\u7684\uff1f \u8ddf\u8e2a\u4ee3\u7801\u5c31\u53ef\u4ee5\u7406\u6e05\u695a\u8fd9\u4e00\u8fc7\u7a0b\uff0c\u8fd9\u91cc\u4ee3\u7801\u7248\u672c\u662fJelly Bean\u3002 CameraHardwareInterface\u521d\u59cb\u5316\u7684\u65f6\u5019\u4f1a\u521d\u59cb\u5316\u597dwindow\u6709\u5173\u7684\u6570\u636e struct camera_preview_window { struct preview_stream_ops nw; void *user; }; struct camera_preview_window mHalPreviewWindow; 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() { … Continue reading Driver\u56de\u6765\u7684\u6570\u636e\u662f\u5982\u4f55\u663e\u793a\u51fa\u6765\u7684<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_gfmr_meta_descriptions":[],"_gfmr_multilingual_taxonomy_terms":[],"footnotes":""},"categories":[7,28,34],"tags":[27],"class_list":["post-647","post","type-post","status-publish","format-standard","hentry","category-android","category-cpp","category-multimedia","tag-camera"],"_links":{"self":[{"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/posts\/647","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/comments?post=647"}],"version-history":[{"count":3,"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/posts\/647\/revisions"}],"predecessor-version":[{"id":649,"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/posts\/647\/revisions\/649"}],"wp:attachment":[{"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/media?parent=647"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/categories?post=647"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/tags?post=647"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}