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
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
|
// Copyright (c) the JPEG XL Project Authors. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// This C++ example decodes a JPEG XL image progressively (input bytes are
// passed in chunks). The example outputs the intermediate steps to PAM files.
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS
#endif
#include <jxl/decode.h>
#include <jxl/decode_cxx.h>
#include <jxl/resizable_parallel_runner.h>
#include <jxl/resizable_parallel_runner_cxx.h>
#include <limits.h>
#include <cinttypes> // PRIu64
#include <cstdint>
#include <cstdio>
#include <cstring>
#include <vector>
bool WritePAM(const char* filename, const uint8_t* buffer, size_t w, size_t h) {
FILE* fp = fopen(filename, "wb");
if (!fp) {
fprintf(stderr, "Could not open %s for writing", filename);
return false;
}
fprintf(fp,
"P7\nWIDTH %d\nHEIGHT %d\nDEPTH 4\nMAXVAL 255\nTUPLTYPE "
"RGB_ALPHA\nENDHDR\n",
static_cast<int>(w), static_cast<int>(h));
size_t num_bytes = w * h * 4;
if (fwrite(buffer, 1, num_bytes, fp) != num_bytes) {
fclose(fp);
return false;
};
if (fclose(fp) != 0) {
return false;
}
return true;
}
/** Decodes JPEG XL image to 8-bit integer RGBA pixels and an ICC Profile, in a
* progressive way, saving the intermediate steps.
*/
bool DecodeJpegXlProgressive(const uint8_t* jxl, size_t size,
const char* filename, size_t chunksize) {
std::vector<uint8_t> pixels;
std::vector<uint8_t> icc_profile;
size_t xsize = 0;
size_t ysize = 0;
// Multi-threaded parallel runner.
auto runner = JxlResizableParallelRunnerMake(nullptr);
auto dec = JxlDecoderMake(nullptr);
if (JXL_DEC_SUCCESS !=
JxlDecoderSubscribeEvents(dec.get(), JXL_DEC_BASIC_INFO |
JXL_DEC_COLOR_ENCODING |
JXL_DEC_FULL_IMAGE)) {
fprintf(stderr, "JxlDecoderSubscribeEvents failed\n");
return false;
}
if (JXL_DEC_SUCCESS != JxlDecoderSetParallelRunner(dec.get(),
JxlResizableParallelRunner,
runner.get())) {
fprintf(stderr, "JxlDecoderSetParallelRunner failed\n");
return false;
}
JxlBasicInfo info;
JxlPixelFormat format = {4, JXL_TYPE_UINT8, JXL_NATIVE_ENDIAN, 0};
size_t seen = 0;
JxlDecoderSetInput(dec.get(), jxl, chunksize);
size_t remaining = chunksize;
for (;;) {
JxlDecoderStatus status = JxlDecoderProcessInput(dec.get());
if (status == JXL_DEC_ERROR) {
fprintf(stderr, "Decoder error\n");
return false;
} else if (status == JXL_DEC_NEED_MORE_INPUT || status == JXL_DEC_SUCCESS ||
status == JXL_DEC_FULL_IMAGE) {
seen += remaining - JxlDecoderReleaseInput(dec.get());
printf("Flushing after %" PRIu64 " bytes\n", static_cast<uint64_t>(seen));
if (status == JXL_DEC_NEED_MORE_INPUT &&
JXL_DEC_SUCCESS != JxlDecoderFlushImage(dec.get())) {
printf("flush error (no preview yet)\n");
} else {
char fname[1024];
if (snprintf(fname, 1024, "%s-%" PRIu64 ".pam", filename,
static_cast<uint64_t>(seen)) >= 1024) {
fprintf(stderr, "Filename too long\n");
return false;
};
if (!WritePAM(fname, pixels.data(), xsize, ysize)) {
fprintf(stderr, "Error writing progressive output\n");
}
}
remaining = size - seen;
if (remaining > chunksize) remaining = chunksize;
if (remaining == 0) {
if (status == JXL_DEC_NEED_MORE_INPUT) {
fprintf(stderr, "Error, already provided all input\n");
return false;
} else {
return true;
}
}
JxlDecoderSetInput(dec.get(), jxl + seen, remaining);
} else if (status == JXL_DEC_BASIC_INFO) {
if (JXL_DEC_SUCCESS != JxlDecoderGetBasicInfo(dec.get(), &info)) {
fprintf(stderr, "JxlDecoderGetBasicInfo failed\n");
return false;
}
xsize = info.xsize;
ysize = info.ysize;
JxlResizableParallelRunnerSetThreads(
runner.get(),
JxlResizableParallelRunnerSuggestThreads(info.xsize, info.ysize));
} else if (status == JXL_DEC_COLOR_ENCODING) {
// Get the ICC color profile of the pixel data
size_t icc_size;
if (JXL_DEC_SUCCESS !=
JxlDecoderGetICCProfileSize(
dec.get(), JXL_COLOR_PROFILE_TARGET_ORIGINAL, &icc_size)) {
fprintf(stderr, "JxlDecoderGetICCProfileSize failed\n");
return false;
}
icc_profile.resize(icc_size);
if (JXL_DEC_SUCCESS != JxlDecoderGetColorAsICCProfile(
dec.get(), JXL_COLOR_PROFILE_TARGET_ORIGINAL,
icc_profile.data(), icc_profile.size())) {
fprintf(stderr, "JxlDecoderGetColorAsICCProfile failed\n");
return false;
}
} else if (status == JXL_DEC_NEED_IMAGE_OUT_BUFFER) {
size_t buffer_size;
if (JXL_DEC_SUCCESS !=
JxlDecoderImageOutBufferSize(dec.get(), &format, &buffer_size)) {
fprintf(stderr, "JxlDecoderImageOutBufferSize failed\n");
return false;
}
if (buffer_size != xsize * ysize * 4) {
fprintf(stderr, "Invalid out buffer size %" PRIu64 " != %" PRIu64 "\n",
static_cast<uint64_t>(buffer_size),
static_cast<uint64_t>(xsize * ysize * 4));
return false;
}
pixels.resize(xsize * ysize * 4);
if (JXL_DEC_SUCCESS != JxlDecoderSetImageOutBuffer(dec.get(), &format,
pixels.data(),
pixels.size())) {
fprintf(stderr, "JxlDecoderSetImageOutBuffer failed\n");
return false;
}
} else {
fprintf(stderr, "Unknown decoder status\n");
return false;
}
}
}
bool LoadFile(const char* filename, std::vector<uint8_t>* out) {
FILE* file = fopen(filename, "rb");
if (!file) {
return false;
}
if (fseek(file, 0, SEEK_END) != 0) {
fclose(file);
return false;
}
long size = ftell(file); // NOLINT
// Avoid invalid file or directory.
if (size >= LONG_MAX || size < 0) {
fclose(file);
return false;
}
if (fseek(file, 0, SEEK_SET) != 0) {
fclose(file);
return false;
}
out->resize(size);
size_t readsize = fread(out->data(), 1, size, file);
if (fclose(file) != 0) {
return false;
}
return readsize == static_cast<size_t>(size);
}
int main(int argc, char* argv[]) {
if (argc < 3) {
fprintf(
stderr,
"Usage: %s <jxl> <basename> [chunksize]\n"
"Where:\n"
" jxl = input JPEG XL image filename\n"
" basename = prefix of output filenames\n"
" chunksize = loads chunksize bytes at a time and writes\n"
" intermediate results to basename-[bytes loaded].pam\n"
"Output files will be overwritten.\n",
argv[0]);
return 1;
}
const char* jxl_filename = argv[1];
const char* png_filename = argv[2];
std::vector<uint8_t> jxl;
if (!LoadFile(jxl_filename, &jxl)) {
fprintf(stderr, "couldn't load %s\n", jxl_filename);
return 1;
}
size_t chunksize = jxl.size();
if (argc > 3) {
long cs = atol(argv[3]); // NOLINT
if (cs < 100) {
fprintf(stderr, "Chunk size is too low, try at least 100 bytes\n");
return 1;
}
chunksize = cs;
}
if (!DecodeJpegXlProgressive(jxl.data(), jxl.size(), png_filename,
chunksize)) {
fprintf(stderr, "Error while decoding the jxl file\n");
return 1;
}
return 0;
}
|
