1 // Copyright (c) the JPEG XL Project Authors. All rights reserved.
2 //
3 // Use of this source code is governed by a BSD-style
4 // license that can be found in the LICENSE file.
5
6 // This example prints information from the main codestream header.
7
8 #include <inttypes.h>
9 #include <stdint.h>
10 #include <stdio.h>
11 #include <stdlib.h>
12 #include <string.h>
13
14 #include "jxl/decode.h"
15
PrintBasicInfo(FILE * file)16 int PrintBasicInfo(FILE* file) {
17 uint8_t* data = NULL;
18 size_t data_size = 0;
19 // In how large chunks to read from the file and try decoding the basic info.
20 const size_t chunk_size = 64;
21
22 JxlDecoder* dec = JxlDecoderCreate(NULL);
23 if (!dec) {
24 fprintf(stderr, "JxlDecoderCreate failed\n");
25 return 0;
26 }
27
28 JxlDecoderSetKeepOrientation(dec, 1);
29
30 if (JXL_DEC_SUCCESS != JxlDecoderSubscribeEvents(
31 dec, JXL_DEC_BASIC_INFO | JXL_DEC_COLOR_ENCODING |
32 JXL_DEC_FRAME | JXL_DEC_BOX)) {
33 fprintf(stderr, "JxlDecoderSubscribeEvents failed\n");
34 JxlDecoderDestroy(dec);
35 return 0;
36 }
37
38 JxlBasicInfo info;
39 int seen_basic_info = 0;
40 JxlFrameHeader frame_header;
41
42 for (;;) {
43 // The first time, this will output JXL_DEC_NEED_MORE_INPUT because no
44 // input is set yet, this is ok since the input is set when handling this
45 // event.
46 JxlDecoderStatus status = JxlDecoderProcessInput(dec);
47
48 if (status == JXL_DEC_ERROR) {
49 fprintf(stderr, "Decoder error\n");
50 break;
51 } else if (status == JXL_DEC_NEED_MORE_INPUT) {
52 // The first time there is nothing to release and it returns 0, but that
53 // is ok.
54 size_t remaining = JxlDecoderReleaseInput(dec);
55 // move any remaining bytes to the front if necessary
56 if (remaining != 0) {
57 memmove(data, data + data_size - remaining, remaining);
58 }
59 // resize the buffer to append one more chunk of data
60 // TODO(lode): avoid unnecessary reallocations
61 data = (uint8_t*)realloc(data, remaining + chunk_size);
62 // append bytes read from the file behind the remaining bytes
63 size_t read_size = fread(data + remaining, 1, chunk_size, file);
64 if (read_size == 0 && feof(file)) {
65 fprintf(stderr, "Unexpected EOF\n");
66 break;
67 }
68 data_size = remaining + read_size;
69 JxlDecoderSetInput(dec, data, data_size);
70 if (feof(file)) JxlDecoderCloseInput(dec);
71 } else if (status == JXL_DEC_SUCCESS) {
72 // Finished all processing.
73 break;
74 } else if (status == JXL_DEC_BASIC_INFO) {
75 if (JXL_DEC_SUCCESS != JxlDecoderGetBasicInfo(dec, &info)) {
76 fprintf(stderr, "JxlDecoderGetBasicInfo failed\n");
77 break;
78 }
79
80 seen_basic_info = 1;
81
82 printf("dimensions: %ux%u\n", info.xsize, info.ysize);
83 printf("have_container: %d\n", info.have_container);
84 printf("uses_original_profile: %d\n", info.uses_original_profile);
85 printf("bits_per_sample: %d\n", info.bits_per_sample);
86 if (info.exponent_bits_per_sample)
87 printf("float, with exponent_bits_per_sample: %d\n",
88 info.exponent_bits_per_sample);
89 if (info.intensity_target != 255.f || info.min_nits != 0.f ||
90 info.relative_to_max_display != 0 ||
91 info.relative_to_max_display != 0.f) {
92 printf("intensity_target: %f\n", info.intensity_target);
93 printf("min_nits: %f\n", info.min_nits);
94 printf("relative_to_max_display: %d\n", info.relative_to_max_display);
95 printf("linear_below: %f\n", info.linear_below);
96 }
97 printf("have_preview: %d\n", info.have_preview);
98 if (info.have_preview) {
99 printf("preview xsize: %u\n", info.preview.xsize);
100 printf("preview ysize: %u\n", info.preview.ysize);
101 }
102 printf("have_animation: %d\n", info.have_animation);
103 if (info.have_animation) {
104 printf("ticks per second (numerator / denominator): %u / %u\n",
105 info.animation.tps_numerator, info.animation.tps_denominator);
106 printf("num_loops: %u\n", info.animation.num_loops);
107 printf("have_timecodes: %d\n", info.animation.have_timecodes);
108 }
109 printf("intrinsic xsize: %u\n", info.intrinsic_xsize);
110 printf("intrinsic ysize: %u\n", info.intrinsic_ysize);
111 const char* const orientation_string[8] = {
112 "Normal", "Flipped horizontally",
113 "Upside down", "Flipped vertically",
114 "Transposed", "90 degrees clockwise",
115 "Anti-Transposed", "90 degrees counter-clockwise"};
116 if (info.orientation > 0 && info.orientation < 9) {
117 printf("orientation: %d (%s)\n", info.orientation,
118 orientation_string[info.orientation - 1]);
119 } else {
120 fprintf(stderr, "Invalid orientation\n");
121 }
122 printf("num_color_channels: %d\n", info.num_color_channels);
123 printf("num_extra_channels: %d\n", info.num_extra_channels);
124
125 const char* const ec_type_names[7] = {"Alpha", "Depth",
126 "Spot color", "Selection mask",
127 "K (of CMYK)", "CFA (Bayer data)",
128 "Thermal"};
129 for (uint32_t i = 0; i < info.num_extra_channels; i++) {
130 JxlExtraChannelInfo extra;
131 if (JXL_DEC_SUCCESS != JxlDecoderGetExtraChannelInfo(dec, i, &extra)) {
132 fprintf(stderr, "JxlDecoderGetExtraChannelInfo failed\n");
133 break;
134 }
135 printf("extra channel %u:\n", i);
136 printf(" type: %s\n",
137 (extra.type < 7 ? ec_type_names[extra.type]
138 : (extra.type == JXL_CHANNEL_OPTIONAL
139 ? "Unknown but can be ignored"
140 : "Unknown, please update your libjxl")));
141 printf(" bits_per_sample: %u\n", extra.bits_per_sample);
142 if (extra.exponent_bits_per_sample > 0) {
143 printf(" float, with exponent_bits_per_sample: %u\n",
144 extra.exponent_bits_per_sample);
145 }
146 if (extra.dim_shift > 0) {
147 printf(" dim_shift: %u (upsampled %ux)\n", extra.dim_shift,
148 1 << extra.dim_shift);
149 }
150 if (extra.name_length) {
151 char* name = malloc(extra.name_length + 1);
152 if (JXL_DEC_SUCCESS != JxlDecoderGetExtraChannelName(
153 dec, i, name, extra.name_length + 1)) {
154 fprintf(stderr, "JxlDecoderGetExtraChannelName failed\n");
155 free(name);
156 break;
157 }
158 printf(" name: %s\n", name);
159 free(name);
160 }
161 if (extra.type == JXL_CHANNEL_ALPHA)
162 printf(" alpha_premultiplied: %d (%s)\n", extra.alpha_premultiplied,
163 extra.alpha_premultiplied ? "Premultiplied"
164 : "Non-premultiplied");
165 if (extra.type == JXL_CHANNEL_SPOT_COLOR) {
166 printf(" spot_color: (%f, %f, %f) with opacity %f\n",
167 extra.spot_color[0], extra.spot_color[1], extra.spot_color[2],
168 extra.spot_color[3]);
169 }
170 if (extra.type == JXL_CHANNEL_CFA)
171 printf(" cfa_channel: %u\n", extra.cfa_channel);
172 }
173 } else if (status == JXL_DEC_COLOR_ENCODING) {
174 JxlPixelFormat format = {4, JXL_TYPE_FLOAT, JXL_LITTLE_ENDIAN, 0};
175 printf("color profile:\n");
176
177 JxlColorEncoding color_encoding;
178 if (JXL_DEC_SUCCESS ==
179 JxlDecoderGetColorAsEncodedProfile(dec, &format,
180 JXL_COLOR_PROFILE_TARGET_ORIGINAL,
181 &color_encoding)) {
182 printf(" format: JPEG XL encoded color profile\n");
183 const char* const cs_string[4] = {"RGB color", "Grayscale", "XYB",
184 "Unknown"};
185 const char* const wp_string[12] = {"", "D65", "Custom", "", "", "",
186 "", "", "", "", "E", "P3"};
187 const char* const pr_string[12] = {
188 "", "sRGB", "Custom", "", "", "", "", "", "", "Rec.2100", "", "P3"};
189 const char* const tf_string[19] = {
190 "", "709", "Unknown", "", "", "", "", "", "Linear", "",
191 "", "", "", "sRGB", "", "", "PQ", "DCI", "HLG"};
192 const char* const ri_string[4] = {"Perceptual", "Relative",
193 "Saturation", "Absolute"};
194 printf(" color_space: %d (%s)\n", color_encoding.color_space,
195 cs_string[color_encoding.color_space]);
196 printf(" white_point: %d (%s)\n", color_encoding.white_point,
197 wp_string[color_encoding.white_point]);
198 if (color_encoding.white_point == JXL_WHITE_POINT_CUSTOM) {
199 printf(" white_point XY: %f %f\n", color_encoding.white_point_xy[0],
200 color_encoding.white_point_xy[1]);
201 }
202 if (color_encoding.color_space == JXL_COLOR_SPACE_RGB ||
203 color_encoding.color_space == JXL_COLOR_SPACE_UNKNOWN) {
204 printf(" primaries: %d (%s)\n", color_encoding.primaries,
205 pr_string[color_encoding.primaries]);
206 if (color_encoding.primaries == JXL_PRIMARIES_CUSTOM) {
207 printf(" red primaries XY: %f %f\n",
208 color_encoding.primaries_red_xy[0],
209 color_encoding.primaries_red_xy[1]);
210 printf(" green primaries XY: %f %f\n",
211 color_encoding.primaries_green_xy[0],
212 color_encoding.primaries_green_xy[1]);
213 printf(" blue primaries XY: %f %f\n",
214 color_encoding.primaries_blue_xy[0],
215 color_encoding.primaries_blue_xy[1]);
216 }
217 }
218 if (color_encoding.transfer_function == JXL_TRANSFER_FUNCTION_GAMMA) {
219 printf(" transfer_function: gamma: %f\n", color_encoding.gamma);
220 } else {
221 printf(" transfer_function: %d (%s)\n",
222 color_encoding.transfer_function,
223 tf_string[color_encoding.transfer_function]);
224 }
225 printf(" rendering_intent: %d (%s)\n", color_encoding.rendering_intent,
226 ri_string[color_encoding.rendering_intent]);
227
228 } else {
229 // The profile is not in JPEG XL encoded form, get as ICC profile
230 // instead.
231 printf(" format: ICC profile\n");
232 size_t profile_size;
233 if (JXL_DEC_SUCCESS !=
234 JxlDecoderGetICCProfileSize(dec, &format,
235 JXL_COLOR_PROFILE_TARGET_ORIGINAL,
236 &profile_size)) {
237 fprintf(stderr, "JxlDecoderGetICCProfileSize failed\n");
238 continue;
239 }
240 printf(" ICC profile size: %" PRIu64 "\n", (uint64_t)profile_size);
241 if (profile_size < 132) {
242 fprintf(stderr, "ICC profile too small\n");
243 continue;
244 }
245 uint8_t* profile = (uint8_t*)malloc(profile_size);
246 if (JXL_DEC_SUCCESS !=
247 JxlDecoderGetColorAsICCProfile(dec, &format,
248 JXL_COLOR_PROFILE_TARGET_ORIGINAL,
249 profile, profile_size)) {
250 fprintf(stderr, "JxlDecoderGetColorAsICCProfile failed\n");
251 free(profile);
252 continue;
253 }
254 printf(" CMM type: \"%.4s\"\n", profile + 4);
255 printf(" color space: \"%.4s\"\n", profile + 16);
256 printf(" rendering intent: %d\n", (int)profile[67]);
257 free(profile);
258 }
259 } else if (status == JXL_DEC_FRAME) {
260 if (JXL_DEC_SUCCESS != JxlDecoderGetFrameHeader(dec, &frame_header)) {
261 fprintf(stderr, "JxlDecoderGetFrameHeader failed\n");
262 break;
263 }
264 printf("frame:\n");
265 if (frame_header.name_length) {
266 char* name = malloc(frame_header.name_length + 1);
267 if (JXL_DEC_SUCCESS !=
268 JxlDecoderGetFrameName(dec, name, frame_header.name_length + 1)) {
269 fprintf(stderr, "JxlDecoderGetFrameName failed\n");
270 free(name);
271 break;
272 }
273 printf(" name: %s\n", name);
274 free(name);
275 }
276 float ms = frame_header.duration * 1000.f *
277 info.animation.tps_denominator / info.animation.tps_numerator;
278 if (info.have_animation) {
279 printf(" duration: %u ticks (%f ms)\n", frame_header.duration, ms);
280 if (info.animation.have_timecodes) {
281 printf(" time code: %X\n", frame_header.timecode);
282 }
283 }
284 if (!frame_header.name_length && !info.have_animation) {
285 printf(" still frame, unnamed\n");
286 }
287 } else if (status == JXL_DEC_BOX) {
288 JxlBoxType type;
289 uint64_t size;
290 JxlDecoderGetBoxType(dec, type, JXL_FALSE);
291 JxlDecoderGetBoxSizeRaw(dec, &size);
292 printf("box: type: \"%c%c%c%c\" size: %" PRIu64 "\n", type[0], type[1],
293 type[2], type[3], (uint64_t)size);
294 } else {
295 fprintf(stderr, "Unexpected decoder status\n");
296 break;
297 }
298 }
299
300 JxlDecoderDestroy(dec);
301 free(data);
302
303 return seen_basic_info;
304 }
305
main(int argc,char * argv[])306 int main(int argc, char* argv[]) {
307 if (argc != 2) {
308 fprintf(stderr,
309 "Usage: %s <jxl>\n"
310 "Where:\n"
311 " jxl = input JPEG XL image filename\n",
312 argv[0]);
313 return 1;
314 }
315
316 const char* jxl_filename = argv[1];
317
318 FILE* file = fopen(jxl_filename, "rb");
319 if (!file) {
320 fprintf(stderr, "Failed to read file %s\n", jxl_filename);
321 return 1;
322 }
323
324 if (!PrintBasicInfo(file)) {
325 fclose(file);
326 fprintf(stderr, "Couldn't print basic info\n");
327 return 1;
328 }
329
330 fclose(file);
331 return 0;
332 }
333