ESP MMAP ASSETS
该模块主要用于打包资源（如图像、字体等），并将其直接映射以供用户访问。
功能
- 添加导入文件类型
支持多种文件格式，如
.bin、.jpg、.ttf等。
- 启用分片 JPG
需要使用
SJPG来解析。参见 LVGL SJPG。
- 启用分片 PNG
需要使用
esp_lv_spng来解析。参见组件 esp_lv_spng。
- 设置分片高度
设置分片高度，依赖于
MMAP_SUPPORT_SJPG或MMAP_SUPPORT_SPNG。
CMake
用户可以选择将图像与应用程序二进制文件、分区表等一起自动刷写到设备上，通过在 idf.py flash 时指定 FLASH_IN_PROJECT。例如：
/* partitions.csv
* --------------------------------------------------------
* | Name | Type | SubType | Offset | Size | Flags |
* --------------------------------------------------------
* | my_spiffs_partition | data | spiffs | | 6000K | |
* --------------------------------------------------------
*/
spiffs_create_partition_assets(my_spiffs_partition my_folder FLASH_IN_PROJECT)
应用示例
生成头文件 (assets_generate.h)
该头文件自动生成，包含内存映射资源的基本定义。
#include "esp_mmap_assets.h"
#define TOTAL_MMAP_FILES 2
#define MMAP_CHECKSUM 0xB043
enum MMAP_FILES {
MMAP_JPG_JPG = 0, /*!< jpg.jpg */
MMAP_PNG_PNG = 1, /*!< png.png */
};
创建资源句柄
资源初始化配置确保与 assets_generate.h 一致。它设置了 max_files 和 checksum，用来验证头文件和内存映射的二进制文件是否匹配。
mmap_assets_handle_t asset_handle;
const mmap_assets_config_t config = {
.partition_label = "my_spiffs_partition",
.max_files = TOTAL_MMAP_FILES,
.checksum = MMAP_CHECKSUM,
};
ESP_ERROR_CHECK(mmap_assets_new(&config, &asset_handle));
资源使用
可以使用 assets_generate.h 中定义的枚举来获取资源信息。
const char *name = mmap_assets_get_name(asset_handle, MMAP_JPG_JPG);
const void *mem = mmap_assets_get_mem(asset_handle, MMAP_JPG_JPG);
int size = mmap_assets_get_size(asset_handle, MMAP_JPG_JPG);
int width = mmap_assets_get_width(asset_handle, MMAP_JPG_JPG);
int height = mmap_assets_get_height(asset_handle, MMAP_JPG_JPG);
ESP_LOGI(TAG, "Name:[%s], Mem:[%p], Size:[%d bytes], Width:[%d px], Height:[%d px]", name, mem, size, width, height);
API 参考
Header File
Functions
-
esp_err_t mmap_assets_new(const mmap_assets_config_t *config, mmap_assets_handle_t *ret_item)
Create a new asset instance.
- 参数
config – [in] Pointer to the asset configuration structure.
ret_item – [out] Pointer to the handle of the newly created asset instance.
- 返回
ESP_OK: Success
ESP_ERR_NO_MEM: Insufficient memory
ESP_ERR_NOT_FOUND: Can’t find partition
ESP_ERR_INVALID_SIZE: File num mismatch
ESP_ERR_INVALID_CRC: Checksum mismatch
-
esp_err_t mmap_assets_del(mmap_assets_handle_t handle)
Delete an asset instance.
- 参数
handle – [in] Asset instance handle.
- 返回
ESP_OK: Success
ESP_ERR_INVALID_ARG: Invalid argument
-
const uint8_t *mmap_assets_get_mem(mmap_assets_handle_t handle, int index)
Get the memory of the asset at the specified index.
- 参数
handle – [in] Asset instance handle.
index – [in] Index of the asset.
- 返回
Pointer to the asset memory, or NULL if index is invalid.
-
const char *mmap_assets_get_name(mmap_assets_handle_t handle, int index)
Get the name of the asset at the specified index.
- 参数
handle – [in] Asset instance handle.
index – [in] Index of the asset.
- 返回
Pointer to the asset name, or NULL if index is invalid.
-
int mmap_assets_get_size(mmap_assets_handle_t handle, int index)
Get the size of the asset at the specified index.
- 参数
handle – [in] Asset instance handle.
index – [in] Index of the asset.
- 返回
Size of the asset, or -1 if index is invalid.
-
int mmap_assets_get_width(mmap_assets_handle_t handle, int index)
Get the width of the asset at the specified index.
- 参数
handle – [in] Asset instance handle.
index – [in] Index of the asset.
- 返回
Width of the asset, or -1 if index is invalid.
-
int mmap_assets_get_height(mmap_assets_handle_t handle, int index)
Get the height of the asset at the specified index.
- 参数
handle – [in] Asset instance handle.
index – [in] Index of the asset.
- 返回
Height of the asset, or -1 if index is invalid.
Structures
-
struct mmap_assets_config_t
Asset configuration structure, contains the asset table and other configuration information.
Type Definitions
-
typedef struct mmap_assets_t *mmap_assets_handle_t
Asset handle type, points to the asset.
Type of asset handle