| Supported Targets | ESP32-S2 | ESP32-S3 | | ----------------- | -------- | -------- | # USB Camera Example ## Overview This example demonstrates how to: - Capture video from a USB camera using the `libuvc` library. - Stream the video over WiFi by hosting a TCP server. The example enumerates connected camera, negotiates selected resolution together with `FPS` and starts capturing video. `frame_callback` function is then invoked after receiving each frame. User can process received frame according to his needs. Optionally, captured video can be visualized on computer with help of `player.py` script located in this example. After setting `Enable streaming` menuconfig option, example will create TCP server upon start, and wait until `player.py` connects to server. Once connection is established, example streams each received frame to computer for visualization. **Notice** that `libuvc` selects highest possible `dwMaxPayloadTransferSize` by default, so example has to manually overwrite this value to 512 bytes (maximum transfer size supported by ESP32-S2/S3). (See the README.md file in the upper level 'examples' directory for more information about examples.) ## How to Use Example ### Hardware Required This example requires any ESP32-S2 or ESP32-S3 with external PSRAM and exposed USB connector attached to USB camera. *ESP module without external PSRAM will fail to initialize* ### Configure the project Following configuration is needed for streaming video: Open the project configuration menu (`idf.py menuconfig`). In the `Example Connection Configuration` menu: * Set the Wi-Fi configuration. * Set `WiFi SSID`. * Set `WiFi Password`. In the `Example Configuration` menu: * Set the Example configuration * `Enable streaming` * Select one of UVC Protocol Mode * `Auto` * `Custom` Optional: If you need, change the other options according to your requirements. Additionally, `player.py` python script makes use of `opencv-python` and `numpy` packages, not included in `idf-env` environment. Run following commands to install: * `pip install opencv-python` * `pip install numpy` #### UVC Protocol Mode: Auto When protocol mode set to Auto, the example tries to make three attempts to negotiatiate the protocol with following parameters: 1 Attempt: 640x480, 15 FPS, MJPEG 2 Attempt: 320x240, 30 FPS, MJPEG 3 Attempt: 320x240, first available FPS, MJPEG If all three attempts result in an error, the example displays the error message and suggests to try another USB UVC Device. #### UVC Protocol Mode: Custom When protocol mode set to Custom, the example tries to negotiate protocol with configured parameters: Attempts, Width, Heighs, FPS, Frame Coding format. After all attemts result in an error, the example displays the error message and suggests to try another USB UVC Device. ### Build and Flash Build the project and flash it to the board, then run the monitor tool to view the serial output: Run `idf.py set-target esp32s2` to set target chip. Run `idf.py -p PORT flash monitor` to build, flash and monitor the project. (To exit the serial monitor, type ``Ctrl-]``.) See the Getting Started Guide for all the steps to configure and use the ESP-IDF to build projects. ## Known limitations Having only Full Speed USB peripheral and hardware limited MPS (maximum packet size) to 512 bytes, ESP32-S2/S3 is capable of reading about 0.5 MB of data per second. When connected to Full Speed USB host, cameras normally provide resolution no larger than 640x480 pixels. Following two supported formats are the most common (both encoded in MJPEG): * 320x240 30 FPS * 640x480 15 FPS ## Tested cameras * Logitech C980 * CANYON CNE-CWC2 ## Example Output ``` ... I (1186) example: Waiting for USB UVC device connection ... I (1606) example: Device found DEVICE CONFIGURATION (0c45:6340/ S) --- Status: idle VideoControl: bcdUVC: 0x0100 VideoStreaming(1): bEndpointAddress: 129 Formats: MJPEGFormat(1) bits per pixel: 0 GUID: 4d4a5047000000000000000000000000 (MJPG) default frame: 1 aspect ratio: 0x0 interlace flags: 00 copy protect: 00 FrameDescriptor(1) capabilities: 00 size: 640x480 bit rate: 24576000-147456000 max frame size: 614400 default interval: 1/30 interval[0]: 1/30 interval[1]: 1/25 interval[2]: 1/20 interval[3]: 1/15 interval[4]: 1/10 interval[5]: 1/5 FrameDescriptor(2) capabilities: 00 size: 352x288 bit rate: 8110080-48660480 max frame size: 202752 default interval: 1/30 interval[0]: 1/30 interval[1]: 1/25 interval[2]: 1/20 interval[3]: 1/15 interval[4]: 1/10 interval[5]: 1/5 FrameDescriptor(3) capabilities: 00 size: 320x240 bit rate: 6144000-36864000 max frame size: 153600 default interval: 1/30 interval[0]: 1/30 interval[1]: 1/25 interval[2]: 1/20 interval[3]: 1/15 interval[4]: 1/10 interval[5]: 1/5 FrameDescriptor(4) capabilities: 00 size: 176x144 bit rate: 2027520-12165120 max frame size: 50688 default interval: 1/30 interval[0]: 1/30 interval[1]: 1/25 interval[2]: 1/20 interval[3]: 1/15 interval[4]: 1/10 interval[5]: 1/5 FrameDescriptor(5) capabilities: 00 size: 160x120 bit rate: 1536000-9216000 max frame size: 38400 default interval: 1/30 interval[0]: 1/30 interval[1]: 1/25 interval[2]: 1/20 interval[3]: 1/15 interval[4]: 1/10 interval[5]: 1/5 StillFrameDescriptor bEndPointAddress: 00 wWidth(1) = 640 wHeight(1) = 480 wWidth(2) = 352 wHeight(2) = 288 wWidth(3) = 320 wHeight(3) = 240 wWidth(4) = 176 wHeight(4) = 144 wWidth(5) = 160 wHeight(5) = 120 END DEVICE CONFIGURATION I (1796) example: Negotiate streaming profile 640x480, fps 15 ... I (1816) example: Negotiation complete. bmHint: 0001 bFormatIndex: 1 bFrameIndex: 1 dwFrameInterval: 666666 wKeyFrameRate: 0 wPFrameRate: 0 wCompQuality: 0 wCompWindowSize: 0 wDelay: 23469 dwMaxVideoFrameSize: 614400 dwMaxPayloadTransferSize: 512 bInterfaceNumber: 1 I (1836) example: Streaming... I (4016) example: fps: 10, bytes per second: 69920 ... I (44916) example: fps: 9, bytes per second: 62928 E (45626) USBH: Device 1 gone I (45636) example: Done streaming. ```