調(diào)用流程如下：

msm_isp_process_axi_irq ->
msm_isp_process_axi_irq_stream ->
msm_isp_process_done_buf ->
msm_isp_buf_done ->
msm_vb2_buf_done ->
vb2_buffer_done

void msm_isp_process_axi_irq_stream（···)
{
    struct msm_isp_buffer *done_buf = NULL;
···
    //填充buf
    done_buf = stream_info->buf[pingpong_bit];
···
    if (stream_info->pending_buf_info.is_buf_done_pending != 1) {
        //處理填充的buf
        msm_isp_process_done_buf(vfe_dev, stream_info,
                done_buf, time_stamp, frame_id);
    }
}

最終調(diào)用到vb2_buffer_done

void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state)
{
    //buffer隊列
    struct vb2_queue *q = vb->vb2_queue;
···

    /* 同步 buffers */
    for (plane = 0; plane < vb->num_planes; ++plane)
        call_void_memop(vb, finish, vb->planes[plane].mem_priv);

    spin_lock_irqsave(&q->done_lock, flags);
    if (state == VB2_BUF_STATE_QUEUED ||
        state == VB2_BUF_STATE_REQUEUEING) {
        vb->state = VB2_BUF_STATE_QUEUED;
    } else {
        /* Add the buffer to the done buffers list */
        list_add_tail(&vb->done_entry, &q->done_list);
        vb->state = state;//設(shè)置buf狀態(tài)
    }
    atomic_dec(&q->owned_by_drv_count);
    spin_unlock_irqrestore(&q->done_lock, flags);
···
}

• 將緩沖區(qū)添加到done buffers鏈表中
  list_add_tail(&vb->done_entry, &q->done_list);
• 設(shè)置buf狀態(tài)：VB2_BUF_STATE_DONE
  vb->state = state;

到這里，我們的數(shù)據(jù)就被填充到kernel的緩沖區(qū)(buffer)富俄，等待用戶空間取數(shù)據(jù)禁炒！
所有的buffer都由vb2_queue隊列管理

三、軟件層面的傳輸

數(shù)據(jù)流框圖如下：

3.1 kernel層

• vb2 queue隊列的申請
  kernel/msm-4.9/drivers/media/platform/msm/camera_v2/camera/camera.c

static int camera_v4l2_open(struct file *filep)
{
...
    /* every stream has a vb2 queue */
    //初始化vbuffer2_queue
    rc = camera_v4l2_vb2_q_init(filep)
···
}

通過camera_v4l2_vb2_q_init為每一個stream申請vb2 queue霍比。

需要注意的是幕袱，這里申請的是 用來存放buffer的隊列。

• buffer的申請
  而buffer的在用戶空間申請的悠瞬，高通使用的是用戶空間緩沖區(qū)（V4L2_MEMORY_USERPTR）
  hardware/qcom/camera/QCamera2/HAL/QCameraMem.cpp

int QCameraMemory::allocOneBuffer(QCameraMemInfo &memInfo,
        unsigned int heap_id, size_t size, bool cached, bool secure_mode)
{
    main_ion_fd = open("/dev/ion", O_RDONLY);
    rc = ioctl(main_ion_fd, ION_IOC_ALLOC, &alloc);
}

為什么使用ION buffer呢们豌？

• ION 是當(dāng)前 Android 流行的內(nèi)存分配管理機制，在多媒體部分中使用的最多浅妆，例如從 Camera 到 Display望迎，
  從 Mediaserver 到 Surfaceflinger，都會利用 ION 進行內(nèi)存分配管理狂打。
• ION-最顯著的特點是它可以被用戶空間的進程之間或者內(nèi)核空間的模塊之間進行內(nèi)存共享擂煞，而且這種共享可以是零拷貝的。

3.2 mm-camera-interface層

3.2.1 CAM_dataPoll線程的創(chuàng)建

這部分的代碼分析會有些繞趴乡，看下圖去理解：

3.2.1節(jié)分析圖

hardware/qcom/camera/QCamera2/stack/mm-camera-interface/src/mm_camera_channel.c

int32_t mm_channel_init(mm_channel_t *my_obj,
                        mm_camera_channel_attr_t *attr,
                        mm_camera_buf_notify_t channel_cb,
                        void *userdata)
{
···
    LOGD("Launch data poll thread in channel open");
    snprintf(my_obj->poll_thread[0].threadName, THREAD_NAME_SIZE, "CAM_dataPoll");
    mm_camera_poll_thread_launch(&my_obj->poll_thread[0],
                                 MM_CAMERA_POLL_TYPE_DATA);

    /* change state to stopped state */
    my_obj->state = MM_CHANNEL_STATE_STOPPED;
    return rc;
}

mm_camera_poll_thread_launch 會創(chuàng)建一個管道对省，讓線程進行通信蝗拿；

• 這里mm_camera_poll_thread_launch在主線程運行
• mm_camera_poll_thread在CAM_dataPoll線程運行

int32_t mm_camera_poll_thread_launch(mm_camera_poll_thread_t * poll_cb,
                                     mm_camera_poll_thread_type_t poll_type)
{

    //Initialize pipe fds
    poll_cb->pfds[0] = -1;
    poll_cb->pfds[1] = -1;
    rc = pipe(poll_cb->pfds);

    /* 創(chuàng)建一個data_poll線程 */
    pthread_create(&poll_cb->pid, NULL, mm_camera_poll_thread, (void *)poll_cb);

<=================================>
static void *mm_camera_poll_thread(void *data)
{
    mm_camera_poll_thread_t *poll_cb = (mm_camera_poll_thread_t *)data;

    mm_camera_cmd_thread_name(poll_cb->threadName);
    /* add pipe read fd into poll first */
    poll_cb->poll_fds[poll_cb->num_fds++].fd = poll_cb->pfds[0];

    mm_camera_poll_sig_done(poll_cb);
    mm_camera_poll_set_state(poll_cb, MM_CAMERA_POLL_TASK_STATE_POLL);
    return mm_camera_poll_fn(poll_cb);
}
<=================================>
    return rc;
}

pthread_create會創(chuàng)建一個data_poll線程，該線程最終會調(diào)用mm_camera_poll_fn蒿涎。

static void *mm_camera_poll_fn(mm_camera_poll_thread_t *poll_cb)
{
    int rc = 0, i;
   ···
    do {
         for(i = 0; i < poll_cb->num_fds; i++) {
            poll_cb->poll_fds[i].events = POLLIN|POLLRDNORM|POLLPRI;
         }
        //輪詢監(jiān)聽fd
         rc = poll(poll_cb->poll_fds, poll_cb->num_fds, poll_cb->timeoutms);
         if(rc > 0) {
            if ((poll_cb->poll_fds[0].revents & POLLIN) &&
                (poll_cb->poll_fds[0].revents & POLLRDNORM)) {
        //管道里面的消息
                /* if we have data on pipe, we only process pipe in this iteration */
                LOGD("cmd received on pipe\n");
                mm_camera_poll_proc_pipe(poll_cb);
            } else {//event 回調(diào)
                for(i=1; i<poll_cb->num_fds; i++) {
                    /* Checking for ctrl events -event 回調(diào)*/
                    if ((poll_cb->poll_type == MM_CAMERA_POLL_TYPE_EVT) &&
                        (poll_cb->poll_fds[i].revents & POLLPRI)) {
                        LOGD("mm_camera_evt_notify\n");
                        if (NULL != poll_cb->poll_entries[i-1].notify_cb) {
                            poll_cb->poll_entries[i-1].notify_cb(poll_cb->poll_entries[i-1].user_data);
                        }
                    }
                    /*data 回調(diào)*/
                    if ((MM_CAMERA_POLL_TYPE_DATA == poll_cb->poll_type) &&
                        (poll_cb->poll_fds[i].revents & POLLIN) &&
                        (poll_cb->poll_fds[i].revents & POLLRDNORM)) {
                        LOGD("mm_stream_data_notify\n");
                        if (NULL != poll_cb->poll_entries[i-1].notify_cb) {
                            poll_cb->poll_entries[i-1].notify_cb(poll_cb->poll_entries[i-1].user_data);
                        }
                    }
                }
            }
        } else {
            /* in error case sleep 10 us and then continue. hard coded here */
            usleep(10);
            continue;
        }
    } while ((poll_cb != NULL) && (poll_cb->state == MM_CAMERA_POLL_TASK_STATE_POLL));
    return NULL;
}

• 死循環(huán)- 輪詢(poll)的方式監(jiān)聽fd哀托，這里只監(jiān)聽了pipe的poll_cb->pfds[0]，后續(xù)data和event都會監(jiān)聽
• 如果管道有消息劳秋，則回調(diào)mm_camera_poll_proc_pipe
• 如果有event事件仓手，調(diào)用相關(guān)回調(diào)mm_camera_evt_notify
• 如果有data數(shù)據(jù)，調(diào)用相關(guān)回調(diào)mm_stream_data_notify
  這里是通過poll_cb->poll_entries[i-1].notify_cb(poll_cb->poll_entries[i-1].user_data調(diào)用回調(diào)函數(shù)mm_stream_data_notify

mm_stream_data_notify是在哪注冊的玻淑？

hardware/qcom/camera/QCamera2/stack/mm-camera-interface/src/mm_camera_stream.c

int32_t mm_stream_qbuf(mm_stream_t *my_obj, mm_camera_buf_def_t *buf)
{
    if (1 == my_obj->queued_buffer_count) {
        uint8_t idx = mm_camera_util_get_index_by_num(
                my_obj->ch_obj->cam_obj->my_num, my_obj->my_hdl);
        /* Add fd to data poll thread */
        LOGH("Add Poll FD %p type: %d idx = %d num = %d fd = %d",···);

        rc = mm_camera_poll_thread_add_poll_fd(&my_obj->ch_obj->poll_thread[0],
                idx, my_obj->my_hdl, my_obj->fd, mm_stream_data_notify,
                (void*)my_obj, mm_camera_async_call);
    }
}

在mm_stream_qbuf調(diào)用函數(shù)mm_camera_poll_thread_add_poll_fd函數(shù) 進行注冊
hardware/qcom/camera/QCamera2/stack/mm-camera-interface/src/mm_camera_thread.c

int32_t mm_camera_poll_thread_add_poll_fd(···)
{
    int32_t rc = -1;

    if (MAX_STREAM_NUM_IN_BUNDLE > idx) {
        poll_cb->poll_entries[idx].fd = fd;//添加Poll FD
        poll_cb->poll_entries[idx].handler = handler;
        poll_cb->poll_entries[idx].notify_cb = notify_cb;//注冊回調(diào)函數(shù)
        poll_cb->poll_entries[idx].user_data = userdata;//data數(shù)據(jù)
        /* send poll entries updated signal to poll thread */
        if (call_type == mm_camera_sync_call ) {
            rc = mm_camera_poll_sig(poll_cb, MM_CAMERA_PIPE_CMD_POLL_ENTRIES_UPDATED);
        } else {
            rc = mm_camera_poll_sig_async(poll_cb,MM_CAMERA_PIPE_CMD_POLL_ENTRIES_UPDATED_ASYNC );
        }
    } else {
        LOGE("invalid handler %d (%d)", handler, idx);
    }
    return rc;
}

該函數(shù)的作用如下：

• 添加Poll FD
• 注冊回調(diào)函數(shù)
• 調(diào)用mm_camera_poll_sig_async往管道里面寫cmd嗽冒，其實就去更新poll_fds

static int32_t mm_camera_poll_sig_async(mm_camera_poll_thread_t *poll_cb,
                                  uint32_t cmd)
{
    /* send through pipe */
    cmd_evt.cmd = cmd;
    /* reset the statue to false */
    poll_cb->status = FALSE;
    /* send cmd to worker */
    ssize_t len = write(poll_cb->pfds[1], &cmd_evt, sizeof(cmd_evt));

}

一旦往poll_cb->pfds[1]寫數(shù)據(jù)，
那么poll(poll_cb->poll_fds, poll_cb->num_fds, poll_cb->timeoutms)就會監(jiān)聽到fd變化
管道有變化补履，就會調(diào)用 mm_camera_poll_proc_pipe(poll_cb);

static void mm_camera_poll_proc_pipe(mm_camera_poll_thread_t *poll_cb)
{
···
    if (MM_CAMERA_POLL_TYPE_DATA == poll_cb->poll_type &&
        poll_cb->num_fds <= MAX_STREAM_NUM_IN_BUNDLE) {
        for(i = 0; i < MAX_STREAM_NUM_IN_BUNDLE; i++) {
                if(poll_cb->poll_entries[i].fd >= 0) {
                    /* fd is valid, we update poll_fds to this fd */
                    poll_cb->poll_fds[poll_cb->num_fds].fd = poll_cb->poll_entries[i].fd;
                    poll_cb->poll_fds[poll_cb->num_fds].events = POLLIN|POLLRDNORM|POLLPRI;
                    poll_cb->num_fds++;
                }
          }
   }
···
}

這里其實就是更新poll_cb->poll_fds添坊，這樣就能輪詢data數(shù)據(jù)了，有數(shù)據(jù)就會調(diào)用相關(guān)回調(diào)箫锤。
poll(poll_cb->poll_fds, poll_cb->num_fds, poll_cb->timeoutms)

mm_stream_data_notify做了什么贬蛙？

static void mm_stream_data_notify(void* user_data)
{
    rc = mm_stream_read_msm_frame(my_obj, &buf_info,(uint8_t)length);
}
int32_t mm_stream_read_msm_frame(mm_stream_t * my_obj,
                                 mm_camera_buf_info_t* buf_info,
                                 uint8_t num_planes)
{
    //調(diào)用VIDIOC_DQBUF從kernel中把buffer取出來
    rc = ioctl(my_obj->fd, VIDIOC_DQBUF, &vb);

    if(buf_info->buf->buf_type == CAM_STREAM_BUF_TYPE_USERPTR) {
        //把取出來buffer數(shù)據(jù)填充到stream_buf
        mm_stream_read_user_buf(my_obj, buf_info);
    }

    mm_stream_handle_rcvd_buf(my_obj, &buf_info, has_cb);
}

• 調(diào)用VIDIOC_DQBUF從kernel中把buffer取出來。
• mm_stream_handle_rcvd_buf :把取出來buffer數(shù)據(jù)填充到stream_buf
• mm_stream_handle_rcvd_buf(my_obj, &buf_info, has_cb)喚醒cmd線程

super_buf的回調(diào)處理

如果stream綁定到channel里谚攒，就會調(diào)用2個回調(diào)函數(shù)阳准，這里篇幅問題，就不展開分析了馏臭。

• mm_channel_dispatch_super_buf
  把super buffer傳給注冊的用戶
• mm_channel_process_stream_buf
  處理super buffer野蝇。

3.2.2 CAM_StrmAppData線程的創(chuàng)建

hardware/qcom/camera/QCamera2/stack/mm-camera-interface/src/mm_camera_channel.c

int32_t mm_channel_start(mm_channel_t *my_obj)
{
        /* start stream */
        rc = mm_stream_fsm_fn(s_objs[i], MM_STREAM_EVT_START,NULL, NULL);  
}

在mm_channel_start的時候，通過MM_STREAM_EVT_START命令去啟動流
hardware/qcom/camera/QCamera2/stack/mm-camera-interface/src/mm_camera_stream.c

int32_t mm_stream_fsm_reg(mm_stream_t * my_obj,
                          mm_stream_evt_type_t evt,
                          void * in_val,
                          void * out_val)
{
    switch(evt) {
    case MM_STREAM_EVT_START:
        {
            uint8_t has_cb = 0;
            uint8_t i;
            /* launch cmd thread if CB is not null */
            pthread_mutex_lock(&my_obj->cb_lock);
            for (i = 0; i < MM_CAMERA_STREAM_BUF_CB_MAX; i++) {
                if((NULL != my_obj->buf_cb[i].cb) &&
                        (my_obj->buf_cb[i].cb_type != MM_CAMERA_STREAM_CB_TYPE_SYNC)) {
                    has_cb = 1;
                    break;
                }
            }
            pthread_mutex_unlock(&my_obj->cb_lock);

            pthread_mutex_lock(&my_obj->cmd_lock);
            if (has_cb) {
                snprintf(my_obj->cmd_thread.threadName, THREAD_NAME_SIZE, "CAM_StrmAppData");
                //創(chuàng)建CAM_StrmAppData線程
                mm_camera_cmd_thread_launch(&my_obj->cmd_thread,
                                            mm_stream_dispatch_app_data,
                                            (void *)my_obj);
            }
            pthread_mutex_unlock(&my_obj->cmd_lock);
            //設(shè)置stream狀態(tài)
            my_obj->state = MM_STREAM_STATE_ACTIVE;
            //啟動stream
            rc = mm_stream_streamon(my_obj);
        }
        break;
}

• 判斷stream是否有callback函數(shù)
• 如果有位喂，就創(chuàng)建CAM_StrmAppData線程浪耘，回調(diào)函數(shù)為：mm_stream_dispatch_app_data

mm_stream_dispatch_app_data做了什么乱灵？

• 調(diào)用hal層的stream注冊的回調(diào)函數(shù)

/* callback */
my_obj->buf_cb[i].cb(&super_buf,my_obj->buf_cb[i].user_data);

• 釋放buf：mm_stream_buf_done(my_obj, buf_info->buf);

到這里塑崖，我們可能會產(chǎn)生一個疑問，my_obj->buf_cb[i].cb指的是什么痛倚？

my_obj->buf_cb[i].cb在哪里進行了注冊规婆？

void QCameraStream::dataNotifyCB(mm_camera_super_buf_t *recvd_frame,
                                 void *userdata)
{
    LOGD("\n");
    QCameraStream* stream = (QCameraStream *)userdata;
    ···
    *frame = *recvd_frame;
    stream->processDataNotify(frame);
    return;
}

int32_t QCameraStream::processDataNotify(mm_camera_super_buf_t *frame)
{
    //frame入隊
    if (mDataQ.enqueue((void *)frame)) {
      //發(fā)送一條cmd = CAMERA_CMD_TYPE_DO_NEXT_JOB
        return mProcTh.sendCmd(CAMERA_CMD_TYPE_DO_NEXT_JOB, FALSE, FALSE);
    } 
}

• frame入隊
• 發(fā)送一條cmd = CAMERA_CMD_TYPE_DO_NEXT_JOB，并且喚醒cmd線程

分析到這里蝉稳，我們會有疑問抒蚜，cmd線程在哪里創(chuàng)建的，又是怎么處理的耘戚？
接下來看到hal層

3.3 Hal層

CAM_strmDatProc線程的創(chuàng)建

hardware/qcom/camera/QCamera2/HAL/QCameraStream.cpp

int32_t QCameraStream::start()
{
    int32_t rc = 0;
    mDataQ.init();
    //創(chuàng)建一個回調(diào)函數(shù)為dataProcRoutine的線程: CAM_strmDatProc
    rc = mProcTh.launch(dataProcRoutine, this);
<=====================>
   int32_t QCameraCmdThread::launch(···)
  {
    /* launch the thread */
    pthread_create(&cmd_pid,
                   NULL,
                   start_routine,
                   user_data);
    return NO_ERROR;
  }
<=====================>
    ···
    return rc;
}

• 創(chuàng)建一個回調(diào)函數(shù)為dataProcRoutine的線程: CAM_strmDatProc嗡髓，
• 該線程的作用：回調(diào)hal層注冊的函數(shù)

void *QCameraStream::dataProcRoutine(void *data)
{
    int running = 1;
    int ret;
    QCameraStream *pme = (QCameraStream *)data;
    QCameraCmdThread *cmdThread = &pme->mProcTh;
    cmdThread->setName("CAM_strmDatProc");

    do {
        do {
            //線程等待
            ret = cam_sem_wait(&cmdThread->cmd_sem);
            if (ret != 0 && errno != EINVAL) {
                LOGE("cam_sem_wait error (%s)",
                       strerror(errno));
                return NULL;
            }
        } while (ret != 0);

        // we got notified about new cmd avail in cmd queue
        camera_cmd_type_t cmd = cmdThread->getCmd();
        switch (cmd) {
        case CAMERA_CMD_TYPE_DO_NEXT_JOB:
            {
                LOGD("Do next job");
                mm_camera_super_buf_t *frame =
                    (mm_camera_super_buf_t *)pme->mDataQ.dequeue();
                if (NULL != frame) {
                    if (pme->mDataCB != NULL) {
                        pme->mDataCB(frame, pme, pme->mUserData);
                    } else {
                        // no data cb routine, return buf here
                        pme->bufDone(frame);
                        free(frame);
                    }
                }
            }
            break;
···
        }
    } while (running);
    LOGH("X");
    return NULL;
}

• 線程阻塞 cam_sem_wait(&cmdThread->cmd_sem);，等待被喚醒才能繼續(xù)執(zhí)行
• frame出隊：mm_camera_super_buf_t *frame = (mm_camera_super_buf_t *)pme->mDataQ.dequeue()
• 獲取cmd：cmdThread->getCmd()
• 如果收到 cmd = CAMERA_CMD_TYPE_DO_NEXT_JOB收津，調(diào)用pme->mDataCB

CAM_strmDatProc是在哪里被喚醒的饿这？

int32_t QCameraStream::processDataNotify(mm_camera_super_buf_t *frame)
{
    //frame入隊
    if (mDataQ.enqueue((void *)frame)) {
      //發(fā)送一條cmd = CAMERA_CMD_TYPE_DO_NEXT_JOB
        return mProcTh.sendCmd(CAMERA_CMD_TYPE_DO_NEXT_JOB, FALSE, FALSE);
    } 
}

pme->mDataCB在哪注冊的浊伙？

hardware/qcom/camera/QCamera2/HAL/QCamera2HWICallbacks.cpp
以元數(shù)據(jù)流為例子，調(diào)用流程如下:

addStreamToChannel(pChannel, CAM_STREAM_TYPE_METADATA,metadata_stream_cb_routine, this);
pChannel->addStream
pStream->init
在init函數(shù)中：
mDataCB = stream_cb;
mUserData = userdata;

• 元數(shù)據(jù)流cb = metadata_stream_cb_routine
• 預(yù)覽流cb = preview_stream_cb_routine 和 synchronous_stream_cb_routine
• zsl流cb = zsl_channel_cb
• 拍照流 cb = capture_channel_cb_routine
• video流 cb = video_stream_cb_routine

四长捧、應(yīng)用以及debug技巧

應(yīng)用1：算法集成

參考我之前寫的系列博文：
【Camera專題】HAL1- 實現(xiàn)第三方算法并集成到Android系統(tǒng)

應(yīng)用2：分析圖像異常問題

這里分享一個工作中遇到的問題：
現(xiàn)象：在視頻通話時嚣鄙，概率性某一幀圖像閃一下綠屏。
分析：這個問題單純看log是無法解決問題的串结，沒有報錯哑子。
解決：復(fù)現(xiàn)問題，在ISP或者hal層dump出相關(guān)圖像肌割，確定問題出現(xiàn)在那一層卧蜓，然后具體問題具體分析。
當(dāng)時我們dump出hal層圖像把敞，發(fā)現(xiàn)hal層圖像是ok的烦却，因為問題并非出現(xiàn)在底層，而是應(yīng)用層先巴，后來跟應(yīng)用同事溝通其爵，他們使用了OpenGl對圖像進行了處理，導(dǎo)致出現(xiàn)了此問題伸蚯！

如何dump圖像

• 圖像類型

#define QCAMERA_DUMP_FRM_PREVIEW             1
#define QCAMERA_DUMP_FRM_VIDEO               (1<<1)
#define QCAMERA_DUMP_FRM_INPUT_JPEG          (1<<2)
#define QCAMERA_DUMP_FRM_THUMBNAIL           (1<<3)
#define QCAMERA_DUMP_FRM_RAW                 (1<<4)
#define QCAMERA_DUMP_FRM_OUTPUT_JPEG         (1<<5)
#define QCAMERA_DUMP_FRM_INPUT_REPROCESS     (1<<6)

• 1. 拍照raw
  CAM_FORMAT_BAYER_MIPI_RAW_10BPP_GBRG,
  CAM_FORMAT_BAYER_MIPI_RAW_10BPP_GRBG, //29
  CAM_FORMAT_BAYER_MIPI_RAW_10BPP_RGGB, //30
  CAM_FORMAT_BAYER_MIPI_RAW_10BPP_BGGR,

adb root
adb shell setprop persist.vendor.camera.raw_yuv 1
adb shell setprop persist.vendor.camera.snapshot_raw 1
adb shell setprop persist.vendor.camera.dumpimg 16
adb shell setprop persist.vendor.camera.raw.format 29 
adb reboot

• 2. 預(yù)覽raw
  524304 = 0x80010 ：0x8代表raw圖
  QCAMERA_DUMP_FRM_RAW ： 0X10

adb root
adb remount
adb shell chmod 777 /data/vendor/camera 
adb shell setprop persist.vendor.camera.raw_yuv 1
adb shell setprop persist.vendor.camera.preview_raw 1
adb shell setprop persist.vendor.camera.dumpimg 524304
adb shell setprop persist.vendor.camera.dumpimg_num 20//數(shù)量

• 3. ISP/VFE輸出的YUV圖

Preview: adb shell setprop persist.vendor.camera.isp.dump 2
Analysis: adb shell setprop persist.vendor.camera.isp.dump 2048
Snapshot: adb shell setprop persist.vendor.camera.isp.dump 8
Video: adb shell setprop persist.vendor.camera.isp.dump 16

adb shell setprop persist.vendor.camera.isp.dump_cnt 100;//dump yuv的數(shù)量

• 4. Hal輸出的YUV圖
• persist.vendor.camera.dumpimg =1 代表 preview
• persist.vendor.camera.dumpimg =2 代表 video
• persist.vendor.camera.dumpimg =3 代表 preview & video

adb root 
adb shell chmod 777 /data/vendor/camera 
adb shell setprop persist.vendor.camera.dumpimg 1
adb shell setprop persist.vendor.camera.dumpimg_num 100//數(shù)量

• 5.dump h264編碼前后的video

adb root
adb remount

adb shell chmod 777 /data/misc/media
adb shell setenforce 0
adb shell setprop vidc.enc.log.in 1
adb shell setprop vidc.enc.log.out 1

• Stay hungry摩渺，Stay Foolish！