Doorbell_4M

[中文]

1. Introduction

This project is a demo of a USB camera door lock, supporting end-to-end (BK7258 device) to mobile app demonstrations. By default, it supports Shangyun for network transmission.

1.1 Specifications

• Hardware configuration:

  • Core board, BK7258_QFN88_9X9_V3.2

  • Display adapter board, BK7258_LCD_interface_V3.0

  • Speaker small board, BK_Module_Speaker_V1.1

  • PSRAM 8M/16M

• Support, UVC

  • Reference peripherals, UVC resolution of 864 * 480

• Support, UAC

• Support, TCP LAN image transmission

• Support UDP LAN image transmission

• Support, Shangyun, P2P image transfer

• Support, LCD RGB/MCU I8080 display

  • Reference peripherals, ST7701SN, 480 * 854 RGB LCD

  • RGB565/RGB888

• Support, hardware/software rotation

  • 0°, 90°, 180°, 270°

• Support, onboard speaker

• Support, MJPEG hardware decoding

  • YUV422

• Support, MJPEG software decoding

  • YUV420

• Support, H264 hardware decoding

• Support, OSD display

  • ARGB888[PNG]

  • Custom Font

1.2 Path

<bk_avdk source code path>/projects/media/doorbell_4M

2. Framework diagram

Please refer to Framework diagram

3. Configuration

Please refer to Configuration

3.1 Differences

The difference between doorbell_4M and doorbell_8M is that the former does not support DVP cameras and does not support the on-board microphone.

The macros supporting 4M are configured on CPU1, The path is media/doorbell_4M/config/bk7258_cp1/config, and the macro configuration differences between the two projects are as follows:

project	marco	value	implication
doorbell_4M	CONFIG_MEDIA_PSRAM_SIZE_4M	Y	PSRAM is 4M
doorbell_8M	CONFIG_MEDIA_PSRAM_SIZE_4M	N	PSRAM is 8M

The allocation of PSRAM with different sizes is shown in the following table. The config file needs to be modified, with the file path as follows:

media/doorbell_4M/config/bk7258/config

media/doorbell_4M/config/bk7258_cp1/config

media/doorbell_4M/config/bk7258_cp2/config

project	doorbell_4M	doorbell_8M
CONFIG_PSRAM_MEM_SLAB_USER_SIZE	0	102400
CONFIG_PSRAM_MEM_SLAB_AUDIO_SIZE	51200	102400
CONFIG_PSRAM_MEM_SLAB_ENCODE_SIZE	946176	1433600
CONFIG_PSRAM_MEM_SLAB_DISPLAY_SIZE	2490368	5701632
CONFIG_PSRAM_HEAP_SIZE (CP0)	0x7D000	0x80000
CONFIG_PSRAM_HEAP_SIZE (CP1)	0x2F000	0x80000

The flow is as shown in the following diagram:

Figure 1. doorbell_4M decode process

Figure 2. doorbell_8M decode process

The main differences in the process are as shown in the following table:

project	decode process
doorbell_4M	Firstly, attempt to obtain the YUV image, and continue with the decoding only after the allocation is successful. The LCD display triggers the next image capture process immediately after completion.
doorbell_8M	Directly decode, and upon failure to obtain the YUV image, immediately release the JPEG and wait for the next frame of JPEG.

4. Demonstration explanation

Please visit APP Usage Document

Demo result: During runtime, UVC, LCD, and AUDIO will be activated. The LCD will display UVC and output JPEG (864X480) images that have been decoded and rotated 90 degrees before being displayed on the LCD (480X854), After decoding, the YUV is encoded with H264 and transmitted to the mobile phone for display via WIFI (864X480).

Hint

If you do not have cloud account permissions, you can use debug mode to set the local area network TCP/UDP image transmission method.

5. Code explanation

Please refer to Code explanation

6. Porting Instructions

For the media module, the biggest difference between the 4M and 8M configurations is the reduction in PSRAM size, which in turn reduces the number of internal buffer images, as shown in the following table:

project	YUV images	JPEG images	H264 images
doorbell_4M	3	4	4
doorbell_8M	5	4	8

To modify the project from 8M FLASH + 8M PSRAM to 4M FLASH + 4M PSRAM, follow the steps below:

Step 1:

Merge the platform code into the project.

Synchronize modifications according to the patch, with the patch commit title being “adapter for new 4+4 psram of W955D8MKY”,

There are a total of four commits, and the code directory and involved files are as shown in the following table:

Step 2:

Synchronize the modifications according to the patch. The patch’s commit title is “PSRAM configuration for image transmission-related buffers when the size is 4M.”

There are three commits in total, and the code directory and involved files are as shown in the following table:

Code Directory	Involved Files
components	display_service/src/lcd_display_service.c media_utils/src/psram_mem_slab.c multimedia/comm/frame_buffer.c multimedia/Kconfig multimedia/pipeline/h264_encode_pipeline.c multimedia/pipeline/h264_encode_pipeline.c multimedia/pipeline/jpeg_get_pipeline.c
bk_idk/components/part_table	CMakeLists.txt part_table.mk
projects	media/doorbell_4M/config/bk7258_cp1/config media/doorbell_4M/config/bk7258_cp2/config media/doorbell_4M/config/bk7258/config media/doorbell_4M/config/bk7258/bk7258_partitions.csv

Key modification points are as shown in the following table:

Involved Files	Key modification points
display_service/src/lcd_display_service.c	Retrieve JPEG image immediately after the display is complete
media_utils/src/psram_mem_slab.c	Prevent circular search in the buffer
multimedia/comm/frame_buffer.c	Reduce the number of internal image buffers
multimedia/Kconfig	Enable the macro CONFIG_MEDIA_PSRAM_SIZE_4M
multimedia/pipeline/h264_encode_pipeline.c multimedia/pipeline/h264_encode_pipeline.c multimedia/pipeline/jpeg_get_pipeline.c	Modify the pipeline flow Reduce the impact of YUV image resizing on the frame rate of the software decoding
CMakeLists.txt part_table.mk	add doorbell_4M project
media/doorbell_4M/config/bk7258_cp1/config media/doorbell_4M/config/bk7258_cp2/config media/doorbell_4M/config/bk7258/config	Enable the macro CONFIG_MEDIA_PSRAM_SIZE_4M Modify PSRAM allocation, moving the USB to run on CP1 The specific modifications to the PSRAM are detailed in the table above.
media/doorbell_4M/config/bk7258/bk7258_partitions.csv	Modify the FLASH space allocation to 4M