Support for image capture on ESP32-CAM modules

[jackmax]

I added code to allow ESP32-CAM modules to capture images and send them over the network. One step closer to having the same functionality as Octoprint, but for a fraction of the price ;)

Code is adapted from Espressif's example web server. Fits in 1227566 bytes of Flash, even though I use a separate web server for streaming images. I also added a new endpoint to the default web server to get and set camera parameters.

The camera.html file is also adapted from the example, it could use some cleanup, optimization and styling to fit with the rest of interface. I'm not good with web development though, so maybe I'll leave it to someone else.

To allow /camera.html to be displayed in the iframe, I modified index.html and changed t.indexOf("rtp://")&&(e="http://"+e) to t.indexOf("rtp://")&&(!(t.startsWith("/")))&&(e="http://"+e)

Below is a screenshot of the new firmware in action:

[luc-github]

the feature is already in ESP3D V3 and webui V3 did you tested it ?

https://github.com/luc-github/ESP3D/tree/3.0 https://github.com/luc-github/ESP3D-WEBUI/tree/3.0

you can also save on ESP32 SD card now https://github.com/luc-github/ESP3D/issues/778

[jackmax]

I tested it now.

• Looks nicer, but lacks configuration features, for example to set the resolution or use LED flash. I noticed camera settings can be changed by making GCode macros, or by embedding esp32cam.html like this:
• esp32cam.html can change camera settings, but no longer works to preview the camera image (takes one picture, then the page has to be refreshed). It would be nice if it did, so you can have a bigger preview of the image.
• Setting camera resolution works incorrectly, e.g. UXGA(1600x1200) actually sets resolution to 1024x768, SXGA(1280x1024) to 800x600, etc.
• Code doesn't compile when CAMERA_DEVICE is set to CAMERA_MODEL_CUSTOM. This is because CAMERA_MODEL_TTGO_T_JOURNAL CAMERA_MODEL_M5STACK_PSRAM_2 CAMERA_MODEL_M5STACK_ESP32CAM CAMERA_MODEL_M5STACK_UNITCAM are not defined, so in expressions like #if CAMERA_DEVICE == CAMERA_MODEL_TTGO_T_JOURNAL the CAMERA_MODEL_TTGO_T_JOURNAL defaults to 0, which is the same number as CAMERA_MODEL_CUSTOM. As a result, the compiler attempts to redefine #define values.
• A compile-time sanity check to ensure ESP3D_RESET_PIN doesn't collide with camera pins would be nice. By default pin 0 is used and with camera enabled puts MCU in a reboot loop (very fun if you use OTA).
• Perhaps you could update README.md in https://github.com/luc-github/ESP3D/tree/3.0 with description of new features? I see there's an Excel spreadsheet describing them, but you can't even preview it on Github.

I guess it's good enough so I'll close this PR.

[luc-github]

About configurations / compilations I did this to avoid such issues : https://github.com/luc-github/ESP3D-Configurator which is live here: https://luc-github.github.io/

The CAMERA_MODEL_TTGO_T_JOURNAL should not be in pins list , the define is even not it list so it is set 0 - I forget to remove it - thank you for pointing this out, I have removed it

The led flash is disabled on ESP32Cam because it conflict with SD Card per my tests, but you can override the setting by controling pin directly with a macro

The camera settings can be added by macro because they do not need to be in main page, because you do not change them all the time, this is not an outside camera, also if you want bigger output of camera you can put the camera output in full page instead of panel, so you will have dedicated page for camera

about features there is a file already : https://github.com/luc-github/ESP3D/blob/3.0/Features.md