1 /*
2 * Copyright (C) 2012 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <errno.h>
18 #include <setjmp.h>
19 #include <stdio.h>
20
21 extern "C" {
22 #include "jpeglib.h"
23 }
24
from565to8(uint16_t p,int start,int bits)25 static inline uint8_t from565to8(uint16_t p, int start, int bits) {
26 uint8_t c = (p >> start) & ((1 << bits) - 1);
27 return (c << (8 - bits)) | (c >> (bits - (8 - bits)));
28 }
29
30 struct sf_jpeg_error_mgr {
31 struct jpeg_error_mgr jerr;
32 jmp_buf longjmp_buffer;
33 };
34
sf_jpeg_error_exit(j_common_ptr cinfo)35 void sf_jpeg_error_exit(j_common_ptr cinfo) {
36 struct sf_jpeg_error_mgr *sf_err = (struct sf_jpeg_error_mgr *)cinfo->err;
37 longjmp(sf_err->longjmp_buffer, 0);
38 }
39
writeJpegFile(const char * filename,uint8_t * frame,int width,int height)40 int writeJpegFile(const char *filename, uint8_t *frame, int width, int height) {
41 struct sf_jpeg_error_mgr sf_err;
42 struct jpeg_compress_struct cinfo;
43 uint8_t row_data[width * 3];
44 JSAMPROW row_pointer = row_data;
45 FILE *f;
46
47 f = fopen(filename, "w");
48 if (!f) {
49 return -errno;
50 }
51
52 cinfo.err = jpeg_std_error(&sf_err.jerr);
53 sf_err.jerr.error_exit = sf_jpeg_error_exit;
54 if (setjmp(sf_err.longjmp_buffer)) {
55 jpeg_destroy_compress(&cinfo);
56 fclose(f);
57 return -1;
58 }
59
60 jpeg_create_compress(&cinfo);
61 jpeg_stdio_dest(&cinfo, f);
62
63 cinfo.image_width = width;
64 cinfo.image_height = height;
65 cinfo.input_components = 3;
66 cinfo.in_color_space = JCS_RGB;
67
68 jpeg_set_defaults(&cinfo);
69 jpeg_set_quality(&cinfo, 80, TRUE);
70
71 jpeg_start_compress(&cinfo, TRUE);
72
73 for (int row = 0; row < height; row++) {
74 uint16_t *src = (uint16_t *)(frame + row * width * 2);
75 uint8_t *dst = row_data;
76 for (int col = 0; col < width; col++) {
77 dst[0] = from565to8(*src, 11, 5);
78 dst[1] = from565to8(*src, 5, 6);
79 dst[2] = from565to8(*src, 0, 5);
80 dst += 3;
81 src++;
82 }
83 jpeg_write_scanlines(&cinfo, &row_pointer, 1);
84 }
85
86 jpeg_finish_compress(&cinfo);
87 jpeg_destroy_compress(&cinfo);
88
89 fclose(f);
90 return 0;
91 }
92