我能够得到一个罗技网络摄像头在阅读了网站上的一些有用提示后，我们知道如何与 Cheese 配合使用。但是我们如何知道“麦克风”是否已连接或正在工作？或者相机上是否有麦克风。
抱歉，我不了解网络摄像头的技术细节，上面没有标签或零件编号；它是从没有盒子或手册的箱子里找到的。
或者我需要一个带麦克风的耳机吗？
Bus 001 Device 004: ID 046d:0804 Logitech, Inc. Webcam C250
Couldn't open device, some information will be missing
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 2.00
bDeviceClass 239 Miscellaneous Device
bDeviceSubClass 2 ?
bDeviceProtocol 1 Interface Association
bMaxPacketSize0 64
idVendor 0x046d **Logitech, Inc.**
idProduct 0x0804 **Webcam C250**
bcdDevice 0.09
iManufacturer 0
iProduct 0
iSerial 2
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 1549
bNumInterfaces 4
bConfigurationValue 1
iConfiguration 0
bmAttributes 0x80
(Bus Powered)
MaxPower 500mA
Interface Association:
bLength 8
bDescriptorType 11
bFirstInterface 0
bInterfaceCount 2
bFunctionClass 14 Video
bFunctionSubClass 3 Video Interface Collection
bFunctionProtocol 0
iFunction 0
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 1
bInterfaceClass 14 Video
bInterfaceSubClass 1 Video Control
bInterfaceProtocol 0
iInterface 0
VideoControl Interface Descriptor:
bLength 13
bDescriptorType 36
bDescriptorSubtype 1 (HEADER)
bcdUVC 1.00
wTotalLength 217
dwClockFrequency 48.000000MHz
bInCollection 1
baInterfaceNr( 0) 1
VideoControl Interface Descriptor:
bLength 18
bDescriptorType 36
bDescriptorSubtype 2 (INPUT_TERMINAL)
bTerminalID 1
wTerminalType 0x0201 Camera Sensor
bAssocTerminal 0
iTerminal 0
wObjectiveFocalLengthMin 0
wObjectiveFocalLengthMax 0
wOcularFocalLength 0
bControlSize 3
bmControls 0x0000000e
Auto-Exposure Mode
Auto-Exposure Priority
Exposure Time (Absolute)
VideoControl Interface Descriptor:
bLength 11
bDescriptorType 36
bDescriptorSubtype 5 (PROCESSING_UNIT)
Warning: Descriptor too short
bUnitID 2
bSourceID 1
wMaxMultiplier 16384
bControlSize 2
bmControls 0x0000175b
Brightness
Contrast
Saturation
Sharpness
White Balance Temperature
Backlight Compensation
Gain
Power Line Frequency
White Balance Temperature, Auto
iProcessing 0
bmVideoStandards 0x1b
None
NTSC - 525/60
SECAM - 625/50
NTSC - 625/50
VideoControl Interface Descriptor:
bLength 27
bDescriptorType 36
bDescriptorSubtype 6 (EXTENSION_UNIT)
bUnitID 4
guidExtensionCode {82066163-7050-ab49-b8cc-b3855e8d221e}
bNumControl 10
bNrPins 1
baSourceID( 0) 2
bControlSize 2
bmControls( 0) 0xff
bmControls( 1) 0x03
iExtension 0
VideoControl Interface Descriptor:
bLength 27
bDescriptorType 36
bDescriptorSubtype 6 (EXTENSION_UNIT)
bUnitID 13
guidExtensionCode {82066163-7050-ab49-b8cc-b3855e8d221f}
bNumControl 7
bNrPins 1
baSourceID( 0) 2
bControlSize 2
bmControls( 0) 0x6f
bmControls( 1) 0x01
iExtension 0
.....
AudioControl Interface Descriptor:
bLength 12
bDescriptorType 36
bDescriptorSubtype 2 (INPUT_TERMINAL)
bTerminalID 1
wTerminalType 0x0201 **Microphone**
bAssocTerminal 0
bNrChannels 1
wChannelConfig 0x0000
iChannelNames 0
iTerminal 0
AudioControl Interface Descriptor:
bLength 9
bDescriptorType 36
bDescriptorSubtype 3 (OUTPUT_TERMINAL)
bTerminalID 3
wTerminalType 0x0101 USB Streaming
bAssocTerminal 1
bSourceID 5
iTerminal 0
AudioControl Interface Descriptor:
bLength 9
好的，所以它是 C250 型号，我猜测根据上面的输出它有一个麦克风......