1. 社区
  2. UVC视频（摄像头）

在模拟uvc设备时遇到一些问题，希望大佬帮忙解解惑

葵 2022-09-28 16:38:40 编辑

目前在模拟一个摄像头，遇到了一些问题，在win10和win11自带的相机软件可以正常显示图像，但是第三方的软件在调用摄像头时黑屏无显示，通过分析仪抓包可以看到数据在正常上传，并且在部分电脑上自带的相机软件也显示黑屏。
上传图片为一张静态图片，图片转为二进制存在单片机内，一个sof传1024KB数据，修改传包间隔没有效果，不知道从什么地方下手，希望大佬帮忙解解惑

设备描述符如下：

        /*---------------------------------------------------------------------------*/
        0x12,                       /* bLength */
        0x01,                       /* bDescriptorType */
        0x00,                       /* bcdUSB */
        0x02,
        0xEF,                       /* bDeviceClass */
        0x02,                       /* bDeviceSubClass */
        0x01,                       /* bDeviceProtocol */
        0x40,                       /* bMaxPacketSize*/
        LOBYTE(DEF_USB_VID),        /* idVendor */
        HIBYTE(DEF_USB_VID),        /* idVendor */
        LOBYTE(DEF_USB_PID),        /* idVendor */
        HIBYTE(DEF_USB_PID),        /* idVendor */
        0x00,                       /* bcdDevice rel. 2.00 */
        0x02,
        0x00,                       /* Index of manufacturer string */
        0x00,                       /* Index of product string */
        0x00,                        /* Index of serial number string */
        0x01                          /* bNumConfigurations */
        /*---------------------------------------------------------------------------*/
配置描述符如下：
        /*---------------------------------------------------------------------------*/
        /*Configuration Descriptor*/
        0x09, /* bLength: Configuation Descriptor size */
        0x02, /* bDescriptorType: Configuration */
        LOBYTE(USB_UVC_CONFIG_DESC_SIZ),     /* wTotalLength: Bytes returned */
        HIBYTE(USB_UVC_CONFIG_DESC_SIZ),
        0x02,         /*bNumInterfaces: 2 interface*/
        0x01,         /*bConfigurationValue: Configuration value*/
        0x04,         /*iConfiguration: Index of string descriptor describing the configuration*/
        0x80,         /*bmAttributes: bus powered device */
        0xFA,         /*MaxPower 500 mA: this current is used for detecting Vbus*/
        /* 09 */
        /*---------------------------------------------------------------------------*/

        /*Interface Association Descriptor*/
        0x08, /* bLength: Interface Association Descriptor size */
        0x0B, /* bDescritorType: Interface Association */
        0x00,         /* bFirstInterface: VideoControl Interface ID */
        0x02,         /* bInterfaceCount: 2 Video Interface */
        0x0E,         /* bFunctionClass: CC_VIDEO */
        0x03,         /* bFunctionSubClass: SC_VIDEO_INTERFACE_COLLECTION */
        0x00,         /* bFunctionProtocol: PC_PROTOCOL_UNDEFINED */
        USBD_IDX_INTERFACE_STR,           /* iFunction: Index of string descriptor descripting the function */

        /*Standard VC Interface Descriptor*/
        0x09, /* bLenght: Standard VC Interface Descriptor size */
        0x04,  /*bDescriptorType: interface */
        0x00,         /* bInterfaceNumber: interface ID */
        0x00,         /* bAlternateSetting: Alternate setting */
        0x00,         /* bNumEndpoints: no endpoint */
        0x0E,         /* bInterfaceClass: CC_VIDEO */
        0x01,         /* bInterfaceSubClass: SC_VIDEOCONTROL */
        0x00,         /* bInterfacePortocol: PC_PROTOCOL_15 */
        USBD_IDX_INTERFACE_STR,           /*iInterface: Index of string descriptor descripting the interface */

        /*Class-specific VC Interface Header Descriptor*/
        0x0D, /* bLength: Class-specific VC Interface Header Descriptor size */
        0x24,         /* bDescriptorType: CS_INTERFACE */
        0x01,         /* bDescriptorSubType: VC_HEADER */
        0x10,         /* bcdUVC: UVC1.5 revision */
        0x01,
        0x27,         /* wTotalLength: total size of class-specific descriptors */
        0x00,
        0x80,         /* dwClockFrequency: deprecated */
        0x8D,
        0x5B,
        0x00,
        0x01,         /* bInCollection: number of streaming interfaces */
        0x01,         /* baInterfaceNr(1): VideoStreaming interface 1 belongs to VC interface */

        /*Input Terminal Descriptor Composite*/
        0x11, /* bLength: Input Terminal Descriptor size */
        0x24,         /* bDescriptorType: CS_INTERFACE */
        0x02,         /* bDescriptorSubType: VC_INPUT_TERMINAL */
        0x01,         /* bTerminalID: Terminal ID */
        0x01,         /* wTerminalType: ITT_CAMERA */
        0x02,
        0x00,         /* bAssocTerminal: no association */
        0x00,         /*iTerminal: index of string descriptor descripting the terminal */
        0x00,         /* wObjectiveFocalLengthMin: No optical zoom supported */
        0x00,
        0x00,         /* wObjectiveFocalLengthMax: No optical zoom supported */
        0x00,
        0x00,         /* wOcularFocalLength: No optical zoom supported */
        0x00,
        0x02,         /* bControlSize: this terminal doesn't implement any controls */
        0x00,         /* bmControls: No controls are supported */
        0x00,

        /*Output Terminal Descriptor*/
        0x09, /* bLength: Output Terminal Descriptor size */
        0x24,         /* bDescriptorType: CS_INTERFACE */
        0x03,         /* bDescriptorSubType: VC_OUTPUT_TERMINAL */
        0x02,         /* bTerminalID: Terminal ID */
        0x01,         /* wTerminalType: TT_STREAMING */
        0x01,
        0x00,         /* bAssocTerminal: no association */
        0x01,         /* bSourceID: connect to the input terminal output pin */
        0x00,         /*iTerminal: index of string descriptor descripting the terminal */

        /*---------------------------------------------------------------------------*/
        /*Standard VS Interface Alternate 0 setting Descriptor*/
        0x09, /* bLength: Standard VS Interface Descriptor size */
        USB_DESC_TYPE_INTERFACE,  /* bDescriptorType: INTERFACE */
        0x01,         /* bInterfaceNumber: Interface ID */
        0x00,         /* bAlternateSetting: index of this alternate setting */
        0x00,         /* bNumEndpoints: 0 endpoint */
        0x0E,         /* bInterfaceClass: CC_VIDEO */
        0x02,         /* bInterfaceSubClass: SC_VIDEOSTREAMING */
        0x00,         /* bInterfaceProtocol: PC_PROTOCOL_15 */
        USBD_IDX_INTERFACE_STR,           /*iInterface: Index of string descriptor descripting the interface */

        /*Class-specific VS Header Descriptor*/
        0x0E, /* bLength: Class-specific VS Header Descriptor size */
        0x24,         /* bDescriptorType: CS_INTERFACE */
        0x01,         /* bDescriptorSubType: VS_INPUT_HEADER */
        0x01,         /* bNumFormats: one format descriptor follows */
        0x3F,//0x45,          /* wTotalLength: Total size of class-specific VS interface descriptors */
        0x00,
        UVC_ISO_DATA_EP,          /* bEndpointAddress: address of isochronour video data endpoint */
        0x00,         /* bmInfo: no dynamic format change supported */
        0x02,         /* bTerminalLink: the terminal ID of output Terminal */
        0x00,         /* bStillCaptureMethod: no supports still image capture method */
        0x00,         /* bTriggerSupport: no supports hardware trigger */
        0x00,         /* bTriggerUsage: initiate still image capture */
        0x01,         /* bControlSize: the size of bmaControls field */
        0x00,         /* bmaControls: no VS specific controls are supported */

        /*Payload Format Descriptor*/
        0x0B, /* blength: Payload Format Descriptor size */
        0x24,         /* bDescriptorType: CS_INTERFACE */
        0x06,         /* bDescriptorSubType: VS_FORMAT_MJPEG */
        0x01,         /* bFormatIndex: index of the format descriptor */
        0x01,         /* bNumFrameDescriptor: number of frame descriptors */
        0x01,         /* bmFlags: FixedSizeSamples */
        0x01,         /* bDefaultFrameIndex: */
        0x00,         /* bAspectRatioX: not required */
        0x00,         /* bAspectRatioY: not required */
        0x00,         /* bInterlaceFlags: non-interlaced stream */
        0x00,         /* bCopyProtect: no restrictions */

        /*Class-specific VS Frame Descriptor*/
        0x26, /* bLength: Class-specific VS Frame Descriptor size */
        0x24,         /* bDescriptorType: CS_INTERFACE */
        0x07,         /* bDescriptorSubType: VS_FRAME_MJPEG */
        0x01,         /* bFrameIndex: index of frame descriptor */
        0x03,         /* bmCapabilities:still image capture method 0 supported,fixed frame-rate */
        LOBYTE(width),         /* wWidth: frame width */
        HIBYTE(width),
        LOBYTE(hight),         /* wHeight: frame height */
        HIBYTE(hight),
        0x00,         /* dwMinBitRate: */
        0xB0,
        0x04,
        0x00,
        0x00,         /* dwMaxBitRate: */
        0x00,
        0x4B,
        0x00,
        0x00,         /* dwMaxVideoFrameBufSize: in bytes */
        0xA0,
        0x00,
        0x00,
        0x2A,         /* dwDefaultFrameInterval: */
        0x2C,
        0x0A,
        0x00,
        0x00,         /* bFrameIntervalType: Continuous frame interval */
        0x2A,         /* dwMinFrameInterval: */
        0x2C,
        0x0A,
        0x00,
        0x2A,         /* dwMaxFrameInterval: */
        0x2C,
        0x0A,
        0x00,
        0x00,         /* dwFrameIntervalSetp: no frame interval step supported */
        0x00,
        0x00,
        0x00,

        /*---------------------------------------------------------------------------*/
        /*Standard VS Interface  Alternate setting 1 Descriptor*/
        0x09, /* bLength: Standard VS Interface Descriptor size */
        USB_DESC_TYPE_INTERFACE,  /* bDescriptorType: INTERFACE */
        0x01,         /* bInterfaceNumber: Interface ID */
        0x01,         /* bAlternateSetting: index of this alternate setting */
        0x01,         /* bNumEndpoints: 1 endpoint */
        0x0E,         /* bInterfaceClass: CC_VIDEO */
        0x02,         /* bInterfaceSubClass: SC_VIDEOSTREAMING */
        0x00,         /* bInterfaceProtocol: PC_PROTOCOL_15 */
        USBD_IDX_INTERFACE_STR,           /*iInterface: Index of string descriptor descripting the interface */

        /*Endpoint Descriptor*/
        0x07, /* bLength: Endpoint Descriptor size */
        0x05,   /* bDescriptorType: ENDPOINT */
        UVC_ISO_DATA_EP,          /* bEndpointAddress: address of isochronour video data endpoint */
        0x05,         /* bmAttributes: Isochronous transfer Asynchronous data type */
        LOBYTE(UVC_ISO_DATA_PACKET_SIZE),     /* wMaxPacketSize: */
        HIBYTE(UVC_ISO_DATA_PACKET_SIZE),
        0x01,         /* bInterval: */
        /**********  Descriptor of UVC interface 0 Alternate setting 0 **************/
USB中文网 2022-09-28 16:45:26 编辑
  • 用BUSHOUND抓包看一下数据传输的过程 - 主要看负载数据头
  • 打开摄像头的VS_COMMIT_CONTROL的数据- 分析数据传输的格式是否正确

应该还是数据的问题，只是不同的应用软件兼容性好一些

葵 2022-09-28 16:51:23 编辑

因为传输静态图片不涉及时钟，所以负载头都是0c 0c传输完成变成0c 0e，下一包的负载头变成0c 0d和0c 0f，然后这样来回翻转

葵 2022-09-29 11:19:43 编辑

我又尝试了一下，我发现确实应该是数据问题，关于UVC数据上报这部分，有什么协议规范或者具体要求的文档描述么

USB中文网 2022-09-29 19:23:13 编辑

主要是查看负载数据头是否正确。如果负载数据头正确，你可以把负载数据头剔除掉，将剩下的数据存存起来，会是一张完整的图片。按指定格式打开。QQ群里有指定格式打开工具。像YUV2,NV12等，JPG的直接换成JPG扩展名主可以用图形工具打开。
负载数据头请参考：https://www.usbzh.com/article/detail-7.html