How to use Amb82-mini as USB camera with NN

Jia_Yan_Lu · July 21, 2025, 8:49am

I want to use Amb82-mini as USB camera with NN, the code below combines sample code of UVC_device and Object detection
The web cam works fine, but the NN seems not working,
the logs show below


#include "StreamIO.h"
#include "VideoStream.h"
#include "RTSP.h"
#include "NNObjectDetection.h"
#include "VideoStreamOverlay.h"
#include "ObjectClassList.h"
#include "UVCD.h"

#define STREAM_CHANNEL 0
#define CHANNELNN 3

// Lower resolution for NN processing
#define NNWIDTH  576
#define NNHEIGHT 320

VideoSetting config(USB_UVCD_STREAM_PRESET);
VideoSetting configNN(NNWIDTH, NNHEIGHT, 10, VIDEO_RGB, 0);
VideoSetting stream_config(USB_UVCD_STREAM_PRESET);
Video camera_uvcd;
NNObjectDetection ObjDet;
StreamIO videoStreamer(1, 1);
StreamIO videoStreamerNN(1, 1);


UVCD usb_uvcd;
unsigned long last_infer_time = 0;
const unsigned long infer_interval = 10000; // 每 1000ms 推論一次

void setup()
{
    Serial.begin(115200);

    // Configure camera video channel with video format information
    config.setBitrate(2 * 1024 * 1024);
    Camera.configVideoChannel(STREAM_CHANNEL, config);
    Camera.configVideoChannel(CHANNELNN, configNN);
    Camera.videoInit();

    // Configure usb_uvcd with identical video format information
    usb_uvcd.configVideo(config);

    // Configure object detection with corresponding video format information
    // Select Neural Network(NN) task and models
    ObjDet.configVideo(configNN);
    ObjDet.modelSelect(OBJECT_DETECTION, DEFAULT_YOLOV4TINY, NA_MODEL, NA_MODEL);
    ObjDet.begin();



    // Configure StreamIO object to stream data from camera video channel to usb_uvcd
    videoStreamer.registerInput(Camera.getStream(STREAM_CHANNEL));
    videoStreamer.registerOutput(usb_uvcd);
    if (videoStreamer.begin() != 0) {
        Serial.println("StreamIO link start failed");
    }

    // Start data stream from video channel
    Camera.channelBegin(STREAM_CHANNEL);

    videoStreamerNN.registerInput(Camera.getStream(CHANNELNN));
    videoStreamerNN.setStackSize();
    videoStreamerNN.setTaskPriority();
    videoStreamerNN.registerOutput(ObjDet);
    if (videoStreamerNN.begin() != 0) {
        Serial.println("StreamIO link start failed");
    }
        // Start video channel for NN
    Camera.channelBegin(CHANNELNN);

    // Start OSD drawing on RTSP video channel
    OSD.configVideo(STREAM_CHANNEL, config);
    OSD.begin();
    // Start usb uvcd
    usb_uvcd.begin(Camera.getStream(STREAM_CHANNEL), videoStreamer.linker, STREAM_CHANNEL);
    //usb_uvcd.begin(Camera.getStream(CHANNELNN), videoStreamerNN.linker, CHANNELNN);
    

}

void loop()
{


    std::vector<ObjectDetectionResult> results = ObjDet.getResult();

    uint16_t im_h = config.height();
    uint16_t im_w = config.width(); 
    Serial.print("Detected objects");
    Serial.print(results.size(), DEC);
    Serial.print("\n\n");
    Serial.print("Total number of objects detected");
    Serial.print(ObjDet.getResultCount(), DEC);
    Serial.print("\n\n");

    OSD.createBitmap(STREAM_CHANNEL);

    if (ObjDet.getResultCount() > 0) {
        for (int i = 0; i < ObjDet.getResultCount(); i++) {
            int obj_type = results[i].type();
            if (itemList[obj_type].filter) {    // check if item should be ignored

                ObjectDetectionResult item = results[i];
                // Result coordinates are floats ranging from 0.00 to 1.00
                // Multiply with RTSP resolution to get coordinates in pixels
                int xmin = (int)(item.xMin() * im_w);
                int xmax = (int)(item.xMax() * im_w);
                int ymin = (int)(item.yMin() * im_h);
                int ymax = (int)(item.yMax() * im_h);

                // Draw boundary box
                printf("Item %d %s:\t%d %d %d %d\n\r", i, itemList[obj_type].objectName, xmin, xmax, ymin, ymax);
                OSD.drawRect(STREAM_CHANNEL, xmin, ymin, xmax, ymax, 3, OSD_COLOR_WHITE);

                // Print identification text
                char text_str[20];
                snprintf(text_str, sizeof(text_str), "%s %d", itemList[obj_type].objectName, item.score());
                OSD.drawText(STREAM_CHANNEL, xmin, ymin - OSD.getTextHeight(STREAM_CHANNEL), text_str, OSD_COLOR_CYAN);
            }
        }
    }
    OSD.update(STREAM_CHANNEL);



    delay(500);
}



YOLOv4t tick[60]


YOLOv4t tick[64]


YOLOv4t tick[58]


YOLOv4t tick[60]


YOLOv4t tick[64]


YOLOv4t tick[58]


YOLOv4t tick[60]


YOLOv4t tick[64]


YOLOv4t tick[58]


>>> YOLOv4t FPS = 6.00


YOLOv4t tick[60]


YOLOv4t tick[64]


YOLOv4t tick[58]


YOLOv4t tick[59]


YOLOv4t tick[62]


YOLOv4t tick[57]


YOLOv4t tick[59]


YOLOv4t tick[61]

KaiFai_Y · July 22, 2025, 1:44am

hi @Jia_Yan_Lu , currently there is an example’s UVCDObjectDetectinLoop at Arduino, you may refer to the guide for more information. Thank you.

Jia_Yan_Lu · July 22, 2025, 3:44am

Thank you, solved!

Jia_Yan_Lu · August 5, 2025, 8:20am

@KaiFai_Y Hi, I wonder if it’s also possible to use Amb82-mini as USB camera with image classification?

KaiFai_Y · August 6, 2025, 1:17am

Hi @Jia_Yan_Lu , you may try on it. You may use the obj detection and image classification examples and modify by changing the classes from ObjDet to imgclass, modelSelect to select image classification model. Lastly, change the ObjectClassList.h.to ClassificationClassList.h. Thank you.

Jia_Yan_Lu · August 6, 2025, 5:14am

Hi, I have tried to merge image classification and UVCD ObjectDetection Loop follow your instruction.

here is my code

/*
 This example describes how to use USB UVCD api with OBJECT_DETECTION.
 In this example, the device is setup to function as a USB camera.
 Connect to PC and use the device as a USB camera.
 Perform objects prediction when the device is connect to PC and PotPlayer.

 Example guide: TBD


 NN Model Selection
 Select Neural Network(NN) task and models using modelSelect(nntask, objdetmodel, facedetmodel, facerecogmodel).
 Replace with NA_MODEL if they are not necessary for your selected NN Task.

 NN task
 =======
 OBJECT_DETECTION/ FACE_DETECTION/ FACE_RECOGNITION

 Models
 =======
 YOLOv3 model         DEFAULT_YOLOV3TINY   / CUSTOMIZED_YOLOV3TINY
 YOLOv4 model         DEFAULT_YOLOV4TINY   / CUSTOMIZED_YOLOV4TINY
 YOLOv7 model         DEFAULT_YOLOV7TINY   / CUSTOMIZED_YOLOV7TINY
 SCRFD model          DEFAULT_SCRFD        / CUSTOMIZED_SCRFD
 MobileFaceNet model  DEFAULT_MOBILEFACENET/ CUSTOMIZED_MOBILEFACENET
 No model             NA_MODEL
 */

#include "StreamIO.h"
#include "VideoStream.h"
#include "UVCD.h"
#include "NNImageClassification.h"
#include "VideoStreamOverlay.h"
#include "ClassificationClassList.h"

#define IMAGERGB 1

#define STREAM_CHANNEL 0
#define CHANNELNN      3

int reconnect = 0;
int disconnect = 0;

Video camera_uvcd;
//NNObjectDetection ObjDet;
NNImageClassification imgclass;
UVCD usb_uvcd;

// Lower resolution for NN processing
#define NNWIDTH  224
#define NNHEIGHT 224

StreamIO videoStreamer(1, 1);    // 1 Input Video -> 1 Output USB_CAM
StreamIO videoStreamerNN(1, 1);
VideoSetting stream_config(USB_UVCD_STREAM_PRESET);
VideoSetting configNN(NNWIDTH, NNHEIGHT, 10, VIDEO_RGB, 0);
VideoSetting config(VIDEO_FHD, 30, VIDEO_H264, 0);
void setup()
{
    Serial.begin(115200);
    // Configure camera video channel with video format information
    camera_uvcd.configVideoChannel(STREAM_CHANNEL, stream_config);

    camera_uvcd.configVideoChannel(CHANNELNN, configNN);
    // Configure usb_uvcd with identical video format information
    usb_uvcd.configVideo(stream_config);
    camera_uvcd.videoInit();

    // Configure object detection with corresponding video format information
    // Select Neural Network(NN) task and models
    //ObjDet.configVideo(configNN);
    //ObjDet.modelSelect(OBJECT_DETECTION, DEFAULT_YOLOV4TINY, NA_MODEL, NA_MODEL);
    //ObjDet.begin();
    imgclass.configVideo(configNN);
    imgclass.configInputImageColor(IMAGERGB);
    imgclass.setResultCallback(ICPostProcess);
    imgclass.modelSelect(IMAGE_CLASSIFICATION, NA_MODEL, NA_MODEL, NA_MODEL, NA_MODEL, DEFAULT_IMGCLASS);
    imgclass.begin();

    // Configure StreamIO object to stream data from camera video channel to usb_uvcd
    videoStreamer.registerInput(camera_uvcd.getStream(STREAM_CHANNEL));
    videoStreamer.registerOutput(usb_uvcd);
    if (videoStreamer.begin() != 0) {
        Serial.println("StreamIO link start failed");
    }
    // Start data stream from video channel
    camera_uvcd.channelBegin(STREAM_CHANNEL);

    // Configure StreamIO object to stream data from RGB video channel to object detection
    videoStreamerNN.registerInput(camera_uvcd.getStream(CHANNELNN));
    videoStreamerNN.setStackSize();
    videoStreamerNN.setTaskPriority();
    videoStreamerNN.registerOutput(imgclass);
    if (videoStreamerNN.begin() != 0) {
        Serial.println("StreamIO link start failed");
    }

    // Start video channel for NN
    camera_uvcd.channelBegin(CHANNELNN);

    // Start usb uvcd for NN
    usb_uvcd.nnbegin(camera_uvcd.getStream(STREAM_CHANNEL), videoStreamer.linker, STREAM_CHANNEL, CHANNELNN, camera_uvcd.videostream_status(STREAM_CHANNEL));

    //OSD.configVideo(STREAM_CHANNEL, config);
    //OSD.begin();
}

void loop()
{

}

void disconnectNN()
{
    camera_uvcd.channelEnd(CHANNELNN);           // Stop video channel from NN
    camera_uvcd.channelBegin(STREAM_CHANNEL);    // Stop video channel from video channel
    reconnect = 1;
    disconnect = 1;
}

void reconnectNN()
{
    camera_uvcd.channelBegin(CHANNELNN);         // Start video channel for NN
    camera_uvcd.channelBegin(STREAM_CHANNEL);    // Start video channel for video channel
    reconnect = 0;
    disconnect = 0;
}
void ICPostProcess(void)
{
    if (!usb_uvcd.isUsbUvcConnected(camera_uvcd.videostream_status(STREAM_CHANNEL))) {
        Serial.println("USB UVC device disconnected");
        // Handle disconnection processes
        if (disconnect == 0) {
            disconnectNN();
        }
        return;
    } 
    else {
        // Handle reconnection or restart processes
        if (reconnect == 1) {
            reconnectNN();
        }  
        int class_id = imgclass.classID();
        if (imgclassItemList[class_id].filter) {    // header file
            float prob = imgclass.score();
            printf("class %d, score: %f, name: %s\r\n", class_id, prob, imgclassItemList[class_id].imgclassName);
        }
    }

    delay(500);
    
}

and now the problem is the webcam works fine, but I did not get any output from image classification

below is the log from plug in and open/close PotPlayer


== Rtl8735b IoT Platform ==

[Normal mode]
BootFromNORFlash
[Start Boot ROM...]
=== Load PARTBL ===
=== Load Done ===
=== Load ISP_IQ ===
[fcs chk pass]
ISP_IQ @ 0x8461080, 0x2ff80, 0x0
mfcs_data version 0x00010001
fcs_data version 0x00010101
=== Process ISP_IQ ===
=== Load Done ===
=== Load BL ===
[Image Start Table @ 0x18200]
=== Load Done ===

== Boot Loader ==
Oct 24 2024:17:41:10
=== Load FCS Para ===
=== Load Done ===
[crc pass]
=== Load ISP_IQ Sensor ===
ISP_IQ @ 0x8461080, 0x2ff80
=== Process ISP_IQ ===
=== Load Done ===
=== Load FW1 ===
FW_ISP_IQ @ 0x8061080, 0x31f80
=== Process FW_ISP_IQ ===
DRAM_TYPE is DDR2 128MB.
ddr_freq = 533
VOE flash @ 0x8093080, 0x80f80
FCS KM_status 0x00002081 err 0x0000200a
                                       Wait KM fcs done 0 us
FCS TM_status 0x003f0000
                         store fcs data for application
                                                        It don't do the sensor initial process
RAM TM_STATUS 0x00bf1208 err 0x00001208
                                        read fcs_status 0x000000bf
                                                                   read fcs_status 0x000000bf
             === Process VOE IMG ===
[Image Start Table @ 0x20106200]
RAM Load @ 0x8114100->0x20106200, 0x6260
DDR Load @ 0x811b080->0x70100000, 0x6dcb0
=== FW Load Done ===

Boot Loader <==

== RAM Start ==
Build @ 17:32:16, Oct 24 2024

$8735b>OTG DRIVER VER: 0826
p_data.len= 2
uvc_hs_streaming_ep= 83
[OTG Err]ERROR:: ep_enable, bogus device state

                                              [video_voe_presetting] fps:30  w:1920  h:1080
fwin(1),enc_en(0),IQ_OFFSET = 0x17b60
 fwin(1),enc_en(0),SENSOR_OFFSET = 0x2fba0
sensor id 1 iq_data 17b60 sensor_data 2fba0
fwin(1),enc_en(0),IQ_OFFSET = 0x17b60
 fwin(1),enc_en(0),SENSOR_OFFSET = 0x2fba0
sensor id 1 iq_data 17b60 sensorset_alt interface 0 alt =0
set_alt interface 1 alt =0
_daset_alt interface 1 alt =0
ta 2fba0
NN IRQ default priority : 0, set to 9
VIPLite Drv version 1.12.0
Deploy Image Classification
set_alt interface 1 alt =0
input 0 dim 416 416 3 1, data format=2, quant_format=2, scale=0.003922, zero_point=0
ouput 0 dim 52 52 255 1, data format=2, scale=0.003919, zero_point=0
ouput 1 dim 26 26 255 1, data format=2, scale=0.003921, zero_point=0
ouput 2 dim 13 13 255 1, data format=2, scale=0.003922, zero_point=0
---------------------------------
input count 1, output count 3
input param 0
        data_format  2
        memory_type  0
        num_of_dims  4
        quant_format 2
        quant_data  , scale=0.003922, zero_point=0
        sizes        416 416 3 1 0 0
output param 0
        data_format  2
        memory_type  0
        num_of_dims  4
        quant_format 2
        quant_data  , scale=0.003919, zero_point=0
        sizes        52 52 255 1 0 0
output param 1
        data_format  2
        memory_type  0
        num_of_dims  4
        quant_format 2
        quant_data  , scale=0.003921, zero_point=0
        sizes        26 26 255 1 0 0
output param 2
        data_format  2
        memory_type  0
        num_of_dims  4
        quant_format 2
        quant_data  , scale=0.003922, zero_point=0
        sizes        13 13 255 1 0 0
---------------------------------
hal_voe_ready 0x0 0xbf1208
 read fcs_status 0x000000bf
[video_init] uvcd iq is null, use default.
[video_init] uvcd SNR is null, use default.
IQ:FW size (98342)
sensor:date 2024/9/12 version:RTL8735B_VOE_1.5.7.0
sensor:FW size (5412)
sensor timestamp: 2024/09/12
iq timestamp: 2023/05/15 14:48:54
voe_heap malloc 0x7020b080, size 19917824
ISP:1 ENC:1 H265:1 NN:1
hal_voe_ready 0x0 0xbf1208
voe   :RTL8735B_VOE_1.5.8.0
sensor:RTL8735B_VOE_1.5.7.0
hal   :RTL8735B_VOE_1.5.8.0
load time sensor:68us iq:1222us itcm:0us dtcm:0us ddr:0us ddr2:0us
Set H264 default HIGH profile
[video_pre_init_procedure] START
[VOE]ext_in = 0 sync = 0
[VOE][Ini set0]init dn 0 hdr 0 mirrorflip 0xf0
[VOE]g_init_fps: 30
[VOE]md init success
[VOE]algo ver 187ea48
[VOE]pack_v 0x0000 0x0002 cus_v 0 iq_id 0 dn 0 day 0 night 1 other 2 offset 224 length 16436 iq_size 32716
[VOE]Ver 0x0001000c Fast3A Cnt AE 1 AWB 1 period AE 5 AWB 1 delay 0 0
[VOE]hdr_mode 0 sensor driver num 1
[VOE]fps max 30.000000 min 2.000000
[VOE]exposure_step 29.629629
[VOE]change sensor mode => 1920x1080@30.000000fps - 'linear'
[VOE]min_fps 2.000000, max_fps 30.000000, exp_step 29.629629 dyn_fps 30.000000
[VOE]md ver 0x6d640100
[VOE]ae ver 0x61650200
[VOE]awb ver 0x77620100
[VOE]short exp mode is not implemented by this sensor.
                                                      [VOE]cur_hdr_mode = 0
[VOE]VOE MEM Size = 19451 Used=  3565 KB Free=15885 KB (16266688)
[VOE]stream 0  buffer 0: 0x70586700 size 3110400
[VOE]stream 0  buffer 1: 0x7087de00 size 3110400
[VOE]first_config_osd2_block_num[0]: 1
[VOE]osd2_block_num[0]: 24
[VOE]NV12 1920x1080 1/30
[VOE]dynamic set fps 0 -> 30 ok
[VOE]short exp mode is not implemented by this sensor.
                                                      [VOE]sensor power on
                                                                          [VOE]early mirror/flip 0 0
[VOE]zoom crop default setting
[VOE]cropw: 1920, croph: 1080
[VOE]scale down set_mcrop
[VOE]status == 1718
[VOE]buffer size == (0x70bb51a0) (1307776 259200) queue(239)
[VOE]Set rate control: bpsqp -1 qpRange I[ 0, 51] PB[ 0, 51]   1048576 bps  pic 1 skip 0  hrd 0  cpbSize 1000000 bitrateWindow 80 intraQpDelta -5 fixedIntraQp  0
[VOE]Set PreP: input [VOE]frame_e1920x1080 :nd: sensor d offset    idn't initia0x0 : formalize done !
ion 0cc 0 : scaling 0 : scaling format 0
[VOE]vcenc_set_ref_pic_set() NULL
                                 hal_voe_send2voe too long 182310 cmd 0x00000206 p1 0x00000000 p2 0x00000000
inputRateNumer[10] < outputRateNumer[30], Set inputRateNumer --> outputRateNumer
[VOE]ext_in = 0 sync = 0
[VOE]isp_device_probe had done
[VOE]isp_soc_start already done
                               [VOE]VOE MEM Size = 19451 Used= 17688 KB Free= 1762 KB (1804768)
[VOE]stream 4  buffer 0: 0x71351300 size 150528
[VOE]stream 4  buffer 1: 0x71376000 size 150528
[VOE]RGB3 224x224 1/10
[VOE]scale down set_mcrop
[VOE]status == 1718
[VOE]release s4 isp buffer 0
[VOE][WARN]useless release s4 slot0 status 0x00000000
[VOE]release s4 isp b[VOE][WARN]slot full : s0 int 0x00000004 buf 0x00000088 time 1293486 cnt 0 slot0 dn 1 rls 0 slot1 1 0 osd_t dn 1 0 rel 0 0
uffer 1
[VOE][WARN]useless release s4 slot1 status 0x00000000
Image Classification tick[76]
USB UVC device disconnected
[VOE]rts_rtsv_streamoff done <1118>
[VOE]rts_rtsv_request_bufs off done<1125>
[VOE]isp_close_stream success <1864>
[VOE]rt_osd2_deinit success <1882>
[VOE]isp_free_buffer success <2001>
hal_voe_send2voe too long 64996 cmd 0x00000207 p1 0x00000000 p2 0x00000004
Set H264 default HIGH profile
[VOE]ext_in = 0 sync = 0
[VOE]isp_device_probe had done
[VOE]isp_soc_start already done
                               [VOE]VOE MEM Size = 19451 Used= 17693 KB Free= 1757 KB (1799520)
[VOE] isp_locate_buffer malloc buffer failed
[VOE]isp_locate_buffer ch0 failed -1
VOE command 0x206 fail ret 0x1
VOE_OPEN_CMD command fail
hal_video_open fail
fun_suspend
fun_suspend
streaming request (req 81 cs 01)
probe
streaming request (req 01 cs 01)
setting commit control, length = 26
format ->7016ada4
interval[0] = 416666
format = 3 w = 1920 h = 1080 fps = 416666
streaming request (req 81 cs 01)
probe
streaming request (req 83 cs 01)
format ->7016ad8c ->7016ad8c
Type_ = 0finish output task
hal_video_output_task closed

format ->7016ad8c ->7016ad8c size 4147200
streaming request (req 82 cs 01)
format ->7016ad8c ->7016ad8c
Type_ = 0
format ->7016ad8c ->7016ad8c size 4147200
[VOE]sensor power off
                     [VOE]rts_rtsv_streamoff done <1118>
[VOE]rts_rtsv_request_bufs off done<1125>
[VOE]isp_close_stream success <1864>
[VOE]ch: 0 rt_osd2_deinit
[VOE]rt_osd2_deinit success <1882>
[VOE]Total HW Memory:   6528032
[VOE]Total SWHW Memory: 51456
[VOE]Total SW Memory:   16320
[VOE]Total Memory:      6595808
[VOE] isp_free_buffer no buffer need to be free
[VOE]isp_free_buffer failed -1
[VOE]voe close failed 0x10
hal_voe_send2voe too long 145992 cmd 0x00000207 p1 0x00000000 p2 0x00000000
VOE command 0x207 fail ret 0x1
VOE_CLOSE_CMD command fail ffffffff
hal_video_close fail
hal_voe_ready 0x0 0x1718
streaming request (req 01 cs 01)
setting commit control, length = 26
format ->7016ada4
interval[0] = 416666
format = 3 w = 1920 h = 1080 fps = 416666
streaming request (req 81 cs 01)
probe
streaming request (req 01 cs 02)
setting set_alt interface 1 alt =1
commit control, length = 26
setting commit control, length = 26
format ->7016ada4
interval[0] = 416666
format = 3 w = 1920 h = 1080 fps = 416666
hal_voe_ready 0x0 0x800000
 read fcs_status 0x00000080
[video_init] uvcd iq is null, use default.
[video_init] uvcd SNR is null, use default.
IQ:FW size (98342)
sensor:date 2024/9/12 version:RTL8735B_VOE_1.5.7.0
sensor:FW size (5412)
sensor timestamp: 2024/09/12
iq timestamp: 2023/05/15 14:48:54
RAM TM_STATUS 0x00801209 err 0x00001209
hal_voe_fcs_check_km_run_bypass 4617
voe:date 2024/10/18 version:RTL8735B_VOE_1.5.8.0
voe:FW size itcm(21792) dtcm(992) ddr(259992) ddr2(241794)
 read fcs_status 0x00000080
ISP:1 ENC:1 H265:1 NN:1
hal_voe_ready 0x1209 0x801209
voe   :RTL8735B_VOE_1.5.8.0
sensor:RTL8735B_VOE_1.5.7.0
hal   :RTL8735B_VOE_1.5.8.0
load time sensor:69us iq:1229us itcm:283us dtcm:15us ddr:3240us ddr2:4155us
Set H264 default HIGH profile
[video_pre_init_procedure] START
[VOE]ext_in = 0 sync = 0
[VOE][Ini set0]init dn 0 hdr 0 mirrorflip 0xf0
[VOE]g_init_fps: 30
[VOE]md init success
[VOE]algo ver 187ea48
[VOE]pack_v 0x0000 0x0002 cus_v 0 iq_id 0 dn 0 day 0 night 1 other 2 offset 224 length 16436 iq_size 32716
[VOE]Ver 0x0001000c Fast3A Cnt AE 1 AWB 1 period AE 5 AWB 1 delay 0 0
[VOE]hdr_mode 0 sensor driver num 1
[VOE]fps max 30.000000 min 2.000000
[VOE]exposure_step 29.629629
[VOE]change sensor mode => 1920x1080@30.000000fps - 'linear'
[VOE]min_fps 2.000000, max_fps 30.000000, exp_step 29.629629 dyn_fps 30.000000
[VOE]md ver 0x6d640100
[VOE]ae ver 0x61650200
[VOE]awb ver 0x77620100
[VOE]short exp mode is not implemented by this sensor.
                                                      [VOE]cur_hdr_mode = 0
[VOE]VOE MEM Size = 19451 Used=  3565 KB Free=15885 KB (16266688)
[VOE]stream 0  buffer 0: 0x70586700 size 3110400
[VOE]stream 0  buffer 1: 0x7087de00 size 3110400
[VOE]first_config_osd2_block_num[0]: 1
[VOE]osd2_block_num[0]: 24
[VOE][Ini set] ae gain 256 exp 10000
[VOE][Ini set] awb r_gain 361 b_gain 378
[VOE][Ini set] gray mode off
[VOE][Ini set] mirrorflip 0xf0
[VOE][Ini set] BRIGHTNESS 0
[VOE][Ini set] SATURATION 40
[VOE][Ini set] CONTRAST 50
[VOE][Ini set] FLICKER 1
[VOE][Ini set] WDR_MODE 2
[VOE][Ini set] WDR_LEVEL 80
[VOE]turn direct_i2c_mode 1
[VOE]NV12 1920x1080 1/30
[VOE]dynamic set fps 0 -> 30 ok
[VOE]short exp mode is not implemented by this sensor.
                                                      [VOE]sensor_start set fast ae cnt 2
[VOE]sensor power on
                    [VOE]early mirror/flip 0 0
[VOE]zoom crop default setting
[VOE]cropw: 1920, croph: 1080
[VOE]scale down set_mcrop
[VOE]status == 1718
[VOE]buffer size == (0x70bb4fa0) (1307776 259200) queue(279)
[VOE]Set rate control: bpsqp -1 qpRange I[ 0, 51] PB[ 0, 51]   1048576 bps  pic 1 skip 0  hrd 0  cpbSize 1000000 bitrateWindow 72 intraQpDelta -5 fixedIntraQp  0
[VOE]Set PreP: input [VOE]frame_e1920x1080 :nd: sensor d offset    idn't initia0x0 : formalize done !
ion 0cc 0 : scaling 0 : scaling format 0
[VOE]vcenc_set_ref_pic_set() NULL
                                 hal_voe_send2voe too long 214667 cmd 0x00000206 p1 0x00000000 p2 0x00000000
stream on
set_alt interface 1 alt =0
deinit iso
Free the buffer
stream RESET
fun_suspend

KaiFai_Y · August 7, 2025, 2:12am

Hi @Jia_Yan_Lu , i saw your call back function ICPostProcess added the if else for disconnect and and connect uvcd handler this should be at the void loop function. Thank you

Jia_Yan_Lu · August 7, 2025, 3:30am

Hi , thanks for the advice!

After follow the instruction, I encounter another problem

void loop()
{
    if (!usb_uvcd.isUsbUvcConnected(camera_uvcd.videostream_status(STREAM_CHANNEL))) {
        Serial.println("USB UVC device disconnected");
        // Handle disconnection processes
        if (disconnect == 0) {
            disconnectNN();
        }
        return;
    } 
    else {
        // Handle reconnection or restart processes
        if (reconnect == 1) {
            reconnectNN();
        }  
        
    }
    //delay(100);
}

void disconnectNN()
{
    camera_uvcd.channelEnd(CHANNELNN);           // Stop video channel from NN
    camera_uvcd.channelBegin(STREAM_CHANNEL);    // Stop video channel from video channel
    reconnect = 1;
    disconnect = 1;
}

void reconnectNN()
{
    camera_uvcd.channelBegin(CHANNELNN);         // Start video channel for NN
    camera_uvcd.channelBegin(STREAM_CHANNEL);    // Start video channel for video channel
    reconnect = 0;
    disconnect = 0;
}
void ICPostProcess(void)
{
    int class_id = imgclass.classID();
    if (imgclassItemList[class_id].filter) {    // header file
        float prob = imgclass.score();
        printf("class %d, score: %f, name: %s\r\n", class_id, prob, imgclassItemList[class_id].imgclassName);
    }   
}

I keep getting “Bus Fault Status: BusFault Address Reg is invalid(Asyn. BusFault)"
I’ve search other discussion of the problem, still don’t sure how to solve it

== Rtl8735b IoT Platform ==

[Normal mode]
BootFromNORFlash
[Start Boot ROM...]
=== Load PARTBL ===
=== Load Done ===
=== Load ISP_IQ ===
[fcs chk pass]
ISP_IQ @ 0x8461080, 0x2ff80, 0x0
mfcs_data version 0x00010001
fcs_data version 0x00010101
=== Process ISP_IQ ===
=== Load Done ===
=== Load BL ===
[Image Start Table @ 0x18200]
=== Load Done ===

== Boot Loader ==
Oct 24 2024:17:41:10
=== Load FCS Para ===
=== Load Done ===
[crc pass]
=== Load ISP_IQ Sensor ===
ISP_IQ @ 0x8461080, 0x2ff80
=== Process ISP_IQ ===
=== Load Done ===
=== Load FW1 ===
FW_ISP_IQ @ 0x8061080, 0x31f80
=== Process FW_ISP_IQ ===
DRAM_TYPE is DDR2 128MB.
ddr_freq = 533
VOE flash @ 0x8093080, 0x80f80
FCS KM_status 0x00002081 err 0x0000200a
                                       Wait KM fcs done 0 us
FCS TM_status 0x003f0000
                         store fcs data for application
                                                        It don't do the sensor initial process
RAM TM_STATUS 0x00bf1208 err 0x00001208
                                        read fcs_status 0x000000bf
                                                                   read fcs_status 0x000000bf
             === Process VOE IMG ===
[Image Start Table @ 0x20106200]
RAM Load @ 0x8114100->0x20106200, 0x6260
DDR Load @ 0x811b080->0x70100000, 0x6dcb0
=== FW Load Done ===

Boot Loader <==

== RAM Start ==
Build @ 17:32:16, Oct 24 2024

$8735b>OTG DRIVER VER: 0826
p_data.len= 2
uvc_hs_streaming_ep= 83
[OTG Err]ERROR:: ep_enable, bogus device state

                                              [video_voe_presetting] fps:30  w:1920  h:1080
fwin(1),enc_en(0),IQ_OFFSET = 0x17b60
 fwin(1),enc_en(0),SENSOR_OFFSET = 0x2fba0
sensor id 1 iq_data 17b60 sensor_data 2fba0
fwin(1),enc_en(0),IQ_OFFSET = 0x17b60
 fwin(1),enc_en(0),SENSOR_OFFSET = 0x2fba0
sensor id 1 iq_data 17b60set_alt interface 0 alt =0
set_alt interface 1 alt =0
set_alt interface 1 alt =0
 sensor_data 2fba0
NN IRQ default priority : 0, set to 9
set_alt interface 1 alt =0
VIPLite Drv version 1.12.0
Deploy Image Classification
input 0 dim 416 416 3 1, data format=2, quant_format=2, scale=0.003922, zero_point=0
ouput 0 dim 52 52 255 1, data format=2, scale=0.003919, zero_point=0
ouput 1 dim 26 26 255 1, data format=2, scale=0.003921, zero_point=0
ouput 2 dim 13 13 255 1, data format=2, scale=0.003922, zero_point=0
---------------------------------
input count 1, output count 3
input param 0
        data_format  2
        memory_type  0
        num_of_dims  4
        quant_format 2
        quant_data  , scale=0.003922, zero_point=0
        sizes        416 416 3 1 0 0
output param 0
        data_format  2
        memory_type  0
        num_of_dims  4
        quant_format 2
        quant_data  , scale=0.003919, zero_point=0
        sizes        52 52 255 1 0 0
output param 1
        data_format  2
        memory_type  0
        num_of_dims  4
        quant_format 2
        quant_data  , scale=0.003921, zero_point=0
        sizes        26 26 255 1 0 0
output param 2
        data_format  2
        memory_type  0
        num_of_dims  4
        quant_format 2
        quant_data  , scale=0.003922, zero_point=0
        sizes        13 13 255 1 0 0
---------------------------------
hal_voe_ready 0x0 0xbf1208
 read fcs_status 0x000000bf
[video_init] uvcd iq is null, use default.
[video_init] uvcd SNR is null, use default.
IQ:FW size (98342)
sensor:date 2024/9/12 version:RTL8735B_VOE_1.5.7.0
sensor:FW size (5412)
sensor timestamp: 2024/09/12
iq timestamp: 2023/05/15 14:48:54
voe_heap malloc 0x7020b160, size 19917824
ISP:1 ENC:1 H265:1 NN:1
hal_voe_ready 0x0 0xbf1208
voe   :RTL8735B_VOE_1.5.8.0
sensor:RTL8735B_VOE_1.5.7.0
hal   :RTL8735B_VOE_1.5.8.0
load time sensor:67us iq:1222us itcm:0us dtcm:0us ddr:0us ddr2:0us
Set H264 default HIGH profile
[video_pre_init_procedure] START
[VOE]ext_in = 0 sync = 0
[VOE][Ini set0]init dn 0 hdr 0 mirrorflip 0xf0
[VOE]g_init_fps: 30
[VOE]md init success
[VOE]algo ver 187ea48
[VOE]pack_v 0x0000 0x0002 cus_v 0 iq_id 0 dn 0 day 0 night 1 other 2 offset 224 length 16436 iq_size 32716
[VOE]Ver 0x0001000c Fast3A Cnt AE 1 AWB 1 period AE 5 AWB 1 delay 0 0
[VOE]hdr_mode 0 sensor driver num 1
[VOE]fps max 30.000000 min 2.000000
[VOE]exposure_step 29.629629
[VOE]change sensor mode => 1920x1080@30.000000fps - 'linear'
[VOE]min_fps 2.000000, max_fps 30.000000, exp_step 29.629629 dyn_fps 30.000000
[VOE]md ver 0x6d640100
[VOE]ae ver 0x61650200
[VOE]awb ver 0x77620100
[VOE]short exp mode is not implemented by this sensor.
                                                      [VOE]cur_hdr_mode = 0
[VOE]VOE MEM Size = 19451 Used=  3565 KB Free=15885 KB (16266688)
[VOE]stream 0  buffer 0: 0x70586800 size 3110400
[VOE]stream 0  buffer 1: 0x7087df00 size 3110400
[VOE]first_config_osd2_block_num[0]: 1
[VOE]osd2_block_num[0]: 24
[VOE]NV12 1920x1080 1/30
[VOE]dynamic set fps 0 -> 30 ok
[VOE]short exp mode is not implemented by this sensor.
                                                      [VOE]sensor power on
                                                                          [VOE]early mirror/flip 0 0
[VOE]zoom crop default setting
[VOE]cropw: 1920, croph: 1080
[VOE]scale down set_mcrop
[VOE]status == 1718
[VOE]buffer size == (0x70bb5280) (1307776 259200) queue(239)
[VOE]Set rate control: bpsqp -1 qpRange I[ 0, 51] PB[ 0, 51]   1048576 bps  pic 1 skip 0  hrd 0  cpbSize 1000000 bitrateWindow 80 intraQpDelta -5 fixedIntraQp  0
[VOE]Set PreP: input [VOE]frame_e1920x1080 :nd: sensor d offset    idn't initia0x0 : formalize done !
ion 0cc 0 : scaling 0 : scaling format 0
[VOE]vcenc_set_ref_pic_set() NULL
                                 hal_voe_send2voe too long 181453 cmd 0x00000206 p1 0x00000000 p2 0x00000000
inputRateNumer[10] < outputRateNumer[30], Set inputRateNumer --> outputRateNumer
[VOE]ext_in = 0 sync = 0
[VOE]isp_device_probe had done
[VOE]isp_soc_start already done
                               [VOE]VOE MEM Size = 19451 Used= 17688 KB Free= 1762 KB (1804768)
[VOE]stream 4  buffer 0: 0x71351400 size 150528
[VOE]stream 4  buffer 1: 0x71376100 size 150528
[VOE]RGB3 224x224 1/10
[VOE]scale down set_mcrop
[VOE]status == 1718
[VOE]release s4 isp buffer 0
[VOE][WARN]useless release s4 slot0 status 0x00000000
[VOE]release s4 isp b[VOE][WARN]slot full : s0 int 0x00000004 buf 0x00000088 time 1287245 cnt 0 slot0 dn 1 rls 0 slot1 1 0 osd_t dn 1 0 rel 0 0
uffer 1
[VOE][WARN]useless release s4 slot1 status 0x00000000
Image Classification tick[76]
Image Classification tick[72]
class 2, score: 0.000000, name: metal
Image Classification tick[74]
class 51, score: 0.000000, name:
Bus Fault:
SCB Configurable Fault Status Reg = 0x00000400

Bus Fault Status:
BusFault Address Reg is invalid(Asyn. BusFault)
Imprecise data bus error:
a data bus error has occurred, but the return address in the stack frame is not related to the instruction that caused the error.

S-domain exception from Thread mode, Extended Stack frame on S-PSP
Registers Saved to stack

Stacked:
R0  = 0x71629cc4
R1  = 0x2c2a0006
R2  = 0xffffffde
R3  = 0x2c2a0007
R4  = 0x10095378
R5  = 0x201068d1
R6  = 0x00000000
R7  = 0x00000000
R8  = 0x00000000
R9  = 0x70151c7c
R10 = 0x00000000
R11 = 0x00000006
R12 = 0x0000001c
LR  = 0x20106625
PC  = 0x10094e1c
PSR = 0x01100000

Current:
LR   = 0xffffffed
MSP  = 0x20003fd8
PSP  = 0x71629b70
xPSR = 0x00000005
CFSR  = 0x00000400
HFSR  = 0x00000000
DFSR  = 0x00000000
MMFAR = 0x00000000
BFAR  = 0x00000000
AFSR  = 0x00000000
PriMask = 0x00000000
SVC priority: 0x00
PendSVC priority: 0xf0
Systick priority: 0xf0

MSP Data:
20003FD8:    70176C3C    FFFFFFF9    20004000    000003E8
20003FE8:    E000E000    70176C3C    07070707    70139D3D
20003FF8:    70139DA8    21000000    BFBFFBAE    B5F5EF57
20004008:    BE9D53D4    647E6F17    160F756A    AFE42FB1
20004018:    7BCB2FE2    BF1EE6E8    C4D98FEE    4BD2347F
20004028:    422422E4    7EF4EA0B    FCD7566B    BBDD5FCF
20004038:    713CE5BE    7C392EB2    DBAA756C    1D10290D
20004048:    3F815B92    5F08AB04    AA0397F4    F7C252AB
20004058:    54848974    73814F75    61079C67    71371544
20004068:    75102EF5    00718427    4414DADD    F6564A1C
20004078:    0119CC24    B80A838E    76FE7CC1    CBD3C8F6
20004088:    445AFC10    90B82266    C28CE59F    E9931B0E
20004098:    BDC408A0    7D8ECDB0    5D438E0F    D6FD783F
200040A8:    6F08E791    B1454FE5    E2DD42A7    42B1F017
200040B8:    AAFF62F6    66D5640E    7857A6EF    D79D7F56
200040C8:    EC98166C    6C43A263    A4ADDA7B    45DBE96F

PSP Data:
71629B70:    71629CC4    2C2A0006    FFFFFFDE    2C2A0007
71629B80:    0000001C    20106625    10094E1C    01100000
71629B90:    201401E8    00000034    50040400    00000010
71629BA0:    9999999B    10095378    201068D1    00000000
71629BB0:    00000000    00000000    20100320    100949A3
71629BC0:    00000020    201068DD    00000000    10095378
71629BD0:    201068D1    100952D1    701F9020    71629CC0
71629BE0:    851EB852    3FE051EB    00000000    00000000
71629BF0:    00000006    10095378    00000000    00000000
71629C00:    2C2A0006    00000000    851EB852    3FE051EB
71629C10:    00000000    00000000    00000000    00000000
71629C20:    00000000    00000000    00000000    00000000
71629C30:    00000000    00000000    00000000    00000000
71629C40:    00000000    00000000    00000000    00000000
71629C50:    00000000    00000000    00000000    00000000
71629C60:    00000000    00000000    30000000    3030302E

 == NS Dump ==
CFSR_NS  = 0x00000000
HFSR_NS  = 0x00000000
DFSR_NS  = 0x00000000
MMFAR_NS = 0x00000000
BFAR_NS  = 0x00000000
AFSR_NS  = 0x00000000
MSP_NS   = 0x00000000
PSP_NS   = 0x00000000
NS HardFault Status Reg = 0x00000000
SCB Configurable Fault Status Reg = 0x00000000
No Back Trace!
[VOE]cmd 0x020b ch 0 notify_tm_message wait ack 10000000

KaiFai_Y · August 7, 2025, 5:52am

hi @Jia_Yan_Lu, now version 4.0.9 had released, you may update in Arduino ide.

Here’s the code:

#include "StreamIO.h"
#include "VideoStream.h"
#include "UVCD.h"
#include "NNImageClassification.h"
#include "VideoStreamOverlay.h"
#include "ClassificationClassList.h"

#define IMAGERGB 1

#define STREAM_CHANNEL 0
#define CHANNELNN      3

int reconnect = 0;
int disconnect = 0;

Video camera_uvcd;
//NNObjectDetection ObjDet;
NNImageClassification imgclass;
UVCD usb_uvcd;

// Lower resolution for NN processing
#define NNWIDTH  224
#define NNHEIGHT 224

StreamIO videoStreamer(1, 1);    // 1 Input Video -> 1 Output USB_CAM
StreamIO videoStreamerNN(1, 1);
VideoSetting stream_config(USB_UVCD_STREAM_PRESET);
VideoSetting configNN(NNWIDTH, NNHEIGHT, 10, VIDEO_RGB, 0);
VideoSetting config(VIDEO_FHD, 30, VIDEO_H264, 0);
void setup()
{
    Serial.begin(115200);
    // Configure camera video channel with video format information
    camera_uvcd.configVideoChannel(STREAM_CHANNEL, stream_config);

    camera_uvcd.configVideoChannel(CHANNELNN, configNN);
    // Configure usb_uvcd with identical video format information
    usb_uvcd.configVideo(stream_config);
    camera_uvcd.videoInit();

    // Configure object detection with corresponding video format information
    // Select Neural Network(NN) task and models
    //ObjDet.configVideo(configNN);
    //ObjDet.modelSelect(OBJECT_DETECTION, DEFAULT_YOLOV4TINY, NA_MODEL, NA_MODEL);
    //ObjDet.begin();
    imgclass.configVideo(configNN);
    imgclass.configInputImageColor(IMAGERGB);
    imgclass.setResultCallback(ICPostProcess);
    imgclass.modelSelect(IMAGE_CLASSIFICATION, NA_MODEL, NA_MODEL, NA_MODEL, NA_MODEL, DEFAULT_IMGCLASS);
    imgclass.begin();

    // Configure StreamIO object to stream data from camera video channel to usb_uvcd
    videoStreamer.registerInput(camera_uvcd.getStream(STREAM_CHANNEL));
    videoStreamer.registerOutput(usb_uvcd);
    if (videoStreamer.begin() != 0) {
        Serial.println("StreamIO link start failed");
    }
    // Start data stream from video channel
    camera_uvcd.channelBegin(STREAM_CHANNEL);

    // Configure StreamIO object to stream data from RGB video channel to object detection
    videoStreamerNN.registerInput(camera_uvcd.getStream(CHANNELNN));
    videoStreamerNN.setStackSize();
    videoStreamerNN.setTaskPriority();
    videoStreamerNN.registerOutput(imgclass);
    if (videoStreamerNN.begin() != 0) {
        Serial.println("StreamIO link start failed");
    }

    // Start video channel for NN
    camera_uvcd.channelBegin(CHANNELNN);

    // Start usb uvcd for NN
    usb_uvcd.nnbegin(camera_uvcd.getStream(STREAM_CHANNEL), videoStreamer.linker, STREAM_CHANNEL, camera_uvcd.videostream_status(STREAM_CHANNEL));

    OSD.configVideo(STREAM_CHANNEL, config);
    OSD.begin();
}

void loop()
{
    if (!usb_uvcd.isUsbUvcConnected(camera_uvcd.videostream_status(STREAM_CHANNEL))) {
        Serial.println("USB UVC device disconnected");
        // Handle disconnection processes
        if (disconnect == 0) {
            disconnectNN();
        }
        return;
    } else {
        // Handle reconnection or restart processes
        if (reconnect == 1) {
            reconnectNN();
        }
        
    }
    
    // delay to wait for new results
    delay(100);
}

void disconnectNN()
{
    camera_uvcd.channelEnd(CHANNELNN);           // Stop video channel from NN
    camera_uvcd.channelBegin(STREAM_CHANNEL);    // Stop video channel from video channel
    reconnect = 1;
    disconnect = 1;
}

void reconnectNN()
{
    camera_uvcd.channelBegin(CHANNELNN);         // Start video channel for NN
    camera_uvcd.channelBegin(STREAM_CHANNEL);    // Start video channel for video channel
    reconnect = 0;
    disconnect = 0;
}

// User callback function
void ICPostProcess(void)
{
    int class_id = imgclass.classID();
    if (imgclassItemList[class_id].filter) {    // header file
        float prob = imgclass.score();
        printf("class %d, score: %f, name: %s\r\n", class_id, prob, imgclassItemList[class_id].imgclassName);
    }
}

Jia_Yan_Lu · August 7, 2025, 8:48am

Hi, thank you so much, solved

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