1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
|
/**
* @file lv_image_decoder.h
*
*/
#ifndef LV_IMAGE_DECODER_H
#define LV_IMAGE_DECODER_H
#ifdef __cplusplus
extern "C" {
#endif
/*********************
* INCLUDES
*********************/
#include "../lv_conf_internal.h"
#include "lv_draw_buf.h"
#include "../misc/lv_fs.h"
#include "../misc/lv_types.h"
#include "../misc/lv_area.h"
#include "../misc/cache/lv_cache.h"
/*********************
* DEFINES
*********************/
/**********************
* TYPEDEFS
**********************/
/**
* Source of image.*/
typedef enum {
LV_IMAGE_SRC_VARIABLE, /** Binary/C variable*/
LV_IMAGE_SRC_FILE, /** File in filesystem*/
LV_IMAGE_SRC_SYMBOL, /** Symbol (@ref lv_symbol_def.h)*/
LV_IMAGE_SRC_UNKNOWN, /** Unknown source*/
} lv_image_src_t;
/**
* Get info from an image and store in the `header`
* @param decoder pointer to decoder object
* @param dsc pointer to decoder descriptor
* @param header store the info here
* @return LV_RESULT_OK: info written correctly; LV_RESULT_INVALID: failed
*/
typedef lv_result_t (*lv_image_decoder_info_f_t)(lv_image_decoder_t * decoder, lv_image_decoder_dsc_t * dsc,
lv_image_header_t * header);
/**
* Open an image for decoding. Prepare it as it is required to read it later
* @param decoder pointer to the decoder the function associated with
* @param dsc pointer to decoder descriptor. `src`, `color` are already initialized in it.
*/
typedef lv_result_t (*lv_image_decoder_open_f_t)(lv_image_decoder_t * decoder, lv_image_decoder_dsc_t * dsc);
/**
* Decode `full_area` pixels incrementally by calling in a loop. Set `decoded_area` values to `LV_COORD_MIN` on first call.
* Required only if the "open" function can't return with the whole decoded pixel array.
* @param decoder pointer to the decoder the function associated with
* @param dsc pointer to decoder descriptor
* @param full_area input parameter. the full area to decode after enough subsequent calls
* @param decoded_area input+output parameter. set the values to `LV_COORD_MIN` for the first call and to reset decoding.
* the decoded area is stored here after each call.
* @return LV_RESULT_OK: ok; LV_RESULT_INVALID: failed or there is nothing left to decode
*/
typedef lv_result_t (*lv_image_decoder_get_area_cb_t)(lv_image_decoder_t * decoder,
lv_image_decoder_dsc_t * dsc,
const lv_area_t * full_area, lv_area_t * decoded_area);
/**
* Close the pending decoding. Free resources etc.
* @param decoder pointer to the decoder the function associated with
* @param dsc pointer to decoder descriptor
*/
typedef void (*lv_image_decoder_close_f_t)(lv_image_decoder_t * decoder, lv_image_decoder_dsc_t * dsc);
/**********************
* GLOBAL PROTOTYPES
**********************/
/**
* Get information about an image.
* Try the created image decoder one by one. Once one is able to get info that info will be used.
* @param src the image source. Can be
* 1) File name: E.g. "S:folder/img1.png" (The drivers needs to registered via `lv_fs_drv_register()`)
* 2) Variable: Pointer to an `lv_image_dsc_t` variable
* 3) Symbol: E.g. `LV_SYMBOL_OK`
* @param header the image info will be stored here
* @return LV_RESULT_OK: success; LV_RESULT_INVALID: wasn't able to get info about the image
*/
lv_result_t lv_image_decoder_get_info(const void * src, lv_image_header_t * header);
/**
* Open an image.
* Try the created image decoders one by one. Once one is able to open the image that decoder is saved in `dsc`
* @param dsc describes a decoding session. Simply a pointer to an `lv_image_decoder_dsc_t` variable.
* @param src the image source. Can be
* 1) File name: E.g. "S:folder/img1.png" (The drivers needs to registered via `lv_fs_drv_register())`)
* 2) Variable: Pointer to an `lv_image_dsc_t` variable
* 3) Symbol: E.g. `LV_SYMBOL_OK`
* @param args args about how the image should be opened.
* @return LV_RESULT_OK: opened the image. `dsc->decoded` and `dsc->header` are set.
* LV_RESULT_INVALID: none of the registered image decoders were able to open the image.
*/
lv_result_t lv_image_decoder_open(lv_image_decoder_dsc_t * dsc, const void * src, const lv_image_decoder_args_t * args);
/**
* Decode `full_area` pixels incrementally by calling in a loop. Set `decoded_area` to `LV_COORD_MIN` on first call.
* @param dsc image decoder descriptor
* @param full_area input parameter. the full area to decode after enough subsequent calls
* @param decoded_area input+output parameter. set the values to `LV_COORD_MIN` for the first call and to reset decoding.
* the decoded area is stored here after each call.
* @return LV_RESULT_OK: success; LV_RESULT_INVALID: an error occurred or there is nothing left to decode
*/
lv_result_t lv_image_decoder_get_area(lv_image_decoder_dsc_t * dsc, const lv_area_t * full_area,
lv_area_t * decoded_area);
/**
* Close a decoding session
* @param dsc pointer to `lv_image_decoder_dsc_t` used in `lv_image_decoder_open`
*/
void lv_image_decoder_close(lv_image_decoder_dsc_t * dsc);
/**
* Create a new image decoder
* @return pointer to the new image decoder
*/
lv_image_decoder_t * lv_image_decoder_create(void);
/**
* Delete an image decoder
* @param decoder pointer to an image decoder
*/
void lv_image_decoder_delete(lv_image_decoder_t * decoder);
/**
* Get the next image decoder in the linked list of image decoders
* @param decoder pointer to an image decoder or NULL to get the first one
* @return the next image decoder or NULL if no more image decoder exists
*/
lv_image_decoder_t * lv_image_decoder_get_next(lv_image_decoder_t * decoder);
/**
* Set a callback to get information about the image
* @param decoder pointer to an image decoder
* @param info_cb a function to collect info about an image (fill an `lv_image_header_t` struct)
*/
void lv_image_decoder_set_info_cb(lv_image_decoder_t * decoder, lv_image_decoder_info_f_t info_cb);
/**
* Set a callback to open an image
* @param decoder pointer to an image decoder
* @param open_cb a function to open an image
*/
void lv_image_decoder_set_open_cb(lv_image_decoder_t * decoder, lv_image_decoder_open_f_t open_cb);
/**
* Set a callback to a decoded line of an image
* @param decoder pointer to an image decoder
* @param read_line_cb a function to read a line of an image
*/
void lv_image_decoder_set_get_area_cb(lv_image_decoder_t * decoder, lv_image_decoder_get_area_cb_t read_line_cb);
/**
* Set a callback to close a decoding session. E.g. close files and free other resources.
* @param decoder pointer to an image decoder
* @param close_cb a function to close a decoding session
*/
void lv_image_decoder_set_close_cb(lv_image_decoder_t * decoder, lv_image_decoder_close_f_t close_cb);
lv_cache_entry_t * lv_image_decoder_add_to_cache(lv_image_decoder_t * decoder,
lv_image_cache_data_t * search_key,
const lv_draw_buf_t * decoded, void * user_data);
/**
* Check the decoded image, make any modification if decoder `args` requires.
* @note A new draw buf will be allocated if provided `decoded` is not modifiable or stride mismatch etc.
* @param dsc pointer to a decoder descriptor
* @param decoded pointer to a decoded image to post process to meet dsc->args requirement.
* @return post processed draw buffer, when it differs with `decoded`, it's newly allocated.
*/
lv_draw_buf_t * lv_image_decoder_post_process(lv_image_decoder_dsc_t * dsc, lv_draw_buf_t * decoded);
/**********************
* MACROS
**********************/
#ifdef __cplusplus
} /*extern "C"*/
#endif
#endif /*LV_IMAGE_DECODER_H*/
|
