Outline ![]()
Files ![]()
loading...
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
/**
******************************************************************************
* @file LibJPEG/LibJPEG_Encoding/Src/encode.c
* @author MCD Application Team
* @brief This file contain the compress method.
******************************************************************************
* @attention
*
* Copyright (c) 2017 STMicroelectronics.
* All rights reserved.
*
* This software is licensed under terms that can be found in the LICENSE file
* in the root directory of this software component.
* If no LICENSE file comes with this software, it is provided AS-IS.
*
******************************************************************************
*/
/* Includes ------------------------------------------------------------------*/
#include "encode.h"
/* Private typedef -----------------------------------------------------------*/
/* This struct contains the JPEG compression parameters */
static struct jpeg_compress_struct cinfo;
/* This struct represents a JPEG error handler */
static struct jpeg_error_mgr jerr;
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
/* Private functions ---------------------------------------------------------*/
extern RGB_typedef *RGB_matrix;
/**
* @brief Jpeg Encode
* @param file: pointer to the bmp file
* @param file1: pointer to the jpg file
* @param width: image width
* @param height: image height
* @param image_quality: image quality
* @param buff: pointer to the image line
* @retval None
*/
void jpeg_encode(JFILE *file, JFILE *file1, uint32_t width, uint32_t height, uint32_t image_quality, uint8_t * buff)
{
/* Encode BMP Image to JPEG */
JSAMPROW row_pointer; /* Pointer to a single row */
uint32_t bytesread;
uint32_t index;
/* Step 1: allocate and initialize JPEG compression object */
/* Set up the error handler */
cinfo.err = jpeg_std_error(&jerr);
/* Initialize the JPEG compression object */
jpeg_create_compress(&cinfo);
/* Step 2: specify data destination */
jpeg_stdio_dest(&cinfo, file1);
/* Step 3: set parameters for compression */
cinfo.image_width = width;
cinfo.image_height = height;
cinfo.input_components = 3;
cinfo.in_color_space = JCS_RGB;
/* Set default compression parameters */
jpeg_set_defaults(&cinfo);
cinfo.dct_method = JDCT_FLOAT;
jpeg_set_quality(&cinfo, image_quality, TRUE);
/* Step 4: start compressor */
jpeg_start_compress(&cinfo, TRUE);
/* Get bitmap data address offset */
f_read(file, buff, 14, (UINT*)&bytesread);
index = *(__IO uint16_t *) (buff + 10);
index |= (*(__IO uint16_t *) (buff + 12)) << 16;
while (cinfo.next_scanline < cinfo.image_height)
{
/* In this application, the input file is a BMP, which first encodes the bottom of the picture */
/* JPEG encodes the highest part of the picture first. We need to read the lines upside down */
/* Move the read pointer to 'last line of the picture - next_scanline' */
f_lseek(file, ((cinfo.image_height-1-cinfo.next_scanline)*width*3)+index);
if(f_read(file, buff, width*3, (UINT*)&bytesread) == FR_OK)
{
row_pointer = (JSAMPROW)buff;
jpeg_write_scanlines(&cinfo, &row_pointer, 1);
}
}
/* Step 5: finish compression */
jpeg_finish_compress(&cinfo);
/* Step 6: release JPEG compression object */
jpeg_destroy_compress(&cinfo);
}