UVC LCD_display

[Chinese]

1 Overview

The UVC screen displays the image information collected by the USB camera, encoded by its internal ISP module, decoded by the software, and finally displayed on the RGB screen in real time.

2 Code Path

demo path：./components/media/camera/camera_act.c, uvc.c, lcd/lcd_act.c

3 Client command

The commands support by demo

Command	Param	Description
media uvc open [psram]	param:resolution, optional	open uvc camera
media lcd open [param]	param:resolution, optional	open lcd display
media uvc close	NULL	close uvc camera
media lcd close	NULL	close lcd

The macro configuration that the demo runs depends on:

NAME	Description	File	value
CONFIG_USB_HOST	配置是否支持usb host	properties\soc\bk7256\bk7256.defconfig	y
CONFIG_USB_UVC	配置是否支持把uvc	properties\soc\bk7256\bk7256.defconfig	y

4 Demo introduction

The steps performed by the demo are as follows:

1. Prepare the uvc camera, the screen is displayed as an RGB screen, and the connection method is as shown below:

2. Send the following commands in sequence:

   media uvc open

   media lcd open

   media lcd close

   media uvc close

Figure 1. uvc connection diagrame

5 Detailed configuration and its description

1. Display initialization instructions:

media uvc open [param]

-[param]: optional parameter, if not written, the default resolution is 640*480.

The supported parameters are determined by the uvc device itself, optional: 1280X720, 640X480, 800X480, 480X320.

media lcd open [param]

-[param]: optional parameter, the default resolution is 480*272 if not written.

-The supported parameters are determined by the LCD device itself, optional: 480X272, 320X480, 1024X600, 480X800

2. The UVC screen shows the software calling process

Figure 2. uvc_display function call

3、Inter-module call of image transmission

Figure 3. uvc_display modules communicate