Commit | Line | Data |
---|---|---|
2ba45a60 DM |
1 | /* |
2 | * copyright (c) 2013 Andrew Kelley | |
3 | * | |
4 | * This file is part of FFmpeg. | |
5 | * | |
6 | * FFmpeg is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU Lesser General Public | |
8 | * License as published by the Free Software Foundation; either | |
9 | * version 2.1 of the License, or (at your option) any later version. | |
10 | * | |
11 | * FFmpeg is distributed in the hope that it will be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
14 | * Lesser General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU Lesser General Public | |
17 | * License along with FFmpeg; if not, write to the Free Software | |
18 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
19 | */ | |
20 | ||
21 | /** | |
22 | * @file | |
23 | * libavfilter API usage example. | |
24 | * | |
25 | * @example filter_audio.c | |
26 | * This example will generate a sine wave audio, | |
27 | * pass it through a simple filter chain, and then compute the MD5 checksum of | |
28 | * the output data. | |
29 | * | |
30 | * The filter chain it uses is: | |
31 | * (input) -> abuffer -> volume -> aformat -> abuffersink -> (output) | |
32 | * | |
33 | * abuffer: This provides the endpoint where you can feed the decoded samples. | |
34 | * volume: In this example we hardcode it to 0.90. | |
35 | * aformat: This converts the samples to the samplefreq, channel layout, | |
36 | * and sample format required by the audio device. | |
37 | * abuffersink: This provides the endpoint where you can read the samples after | |
38 | * they have passed through the filter chain. | |
39 | */ | |
40 | ||
41 | #include <inttypes.h> | |
42 | #include <math.h> | |
43 | #include <stdio.h> | |
44 | #include <stdlib.h> | |
45 | ||
46 | #include "libavutil/channel_layout.h" | |
47 | #include "libavutil/md5.h" | |
48 | #include "libavutil/mem.h" | |
49 | #include "libavutil/opt.h" | |
50 | #include "libavutil/samplefmt.h" | |
51 | ||
52 | #include "libavfilter/avfilter.h" | |
53 | #include "libavfilter/buffersink.h" | |
54 | #include "libavfilter/buffersrc.h" | |
55 | ||
56 | #define INPUT_SAMPLERATE 48000 | |
57 | #define INPUT_FORMAT AV_SAMPLE_FMT_FLTP | |
58 | #define INPUT_CHANNEL_LAYOUT AV_CH_LAYOUT_5POINT0 | |
59 | ||
60 | #define VOLUME_VAL 0.90 | |
61 | ||
62 | static int init_filter_graph(AVFilterGraph **graph, AVFilterContext **src, | |
63 | AVFilterContext **sink) | |
64 | { | |
65 | AVFilterGraph *filter_graph; | |
66 | AVFilterContext *abuffer_ctx; | |
67 | AVFilter *abuffer; | |
68 | AVFilterContext *volume_ctx; | |
69 | AVFilter *volume; | |
70 | AVFilterContext *aformat_ctx; | |
71 | AVFilter *aformat; | |
72 | AVFilterContext *abuffersink_ctx; | |
73 | AVFilter *abuffersink; | |
74 | ||
75 | AVDictionary *options_dict = NULL; | |
76 | uint8_t options_str[1024]; | |
77 | uint8_t ch_layout[64]; | |
78 | ||
79 | int err; | |
80 | ||
81 | /* Create a new filtergraph, which will contain all the filters. */ | |
82 | filter_graph = avfilter_graph_alloc(); | |
83 | if (!filter_graph) { | |
84 | fprintf(stderr, "Unable to create filter graph.\n"); | |
85 | return AVERROR(ENOMEM); | |
86 | } | |
87 | ||
88 | /* Create the abuffer filter; | |
89 | * it will be used for feeding the data into the graph. */ | |
90 | abuffer = avfilter_get_by_name("abuffer"); | |
91 | if (!abuffer) { | |
92 | fprintf(stderr, "Could not find the abuffer filter.\n"); | |
93 | return AVERROR_FILTER_NOT_FOUND; | |
94 | } | |
95 | ||
96 | abuffer_ctx = avfilter_graph_alloc_filter(filter_graph, abuffer, "src"); | |
97 | if (!abuffer_ctx) { | |
98 | fprintf(stderr, "Could not allocate the abuffer instance.\n"); | |
99 | return AVERROR(ENOMEM); | |
100 | } | |
101 | ||
102 | /* Set the filter options through the AVOptions API. */ | |
103 | av_get_channel_layout_string(ch_layout, sizeof(ch_layout), 0, INPUT_CHANNEL_LAYOUT); | |
104 | av_opt_set (abuffer_ctx, "channel_layout", ch_layout, AV_OPT_SEARCH_CHILDREN); | |
105 | av_opt_set (abuffer_ctx, "sample_fmt", av_get_sample_fmt_name(INPUT_FORMAT), AV_OPT_SEARCH_CHILDREN); | |
106 | av_opt_set_q (abuffer_ctx, "time_base", (AVRational){ 1, INPUT_SAMPLERATE }, AV_OPT_SEARCH_CHILDREN); | |
107 | av_opt_set_int(abuffer_ctx, "sample_rate", INPUT_SAMPLERATE, AV_OPT_SEARCH_CHILDREN); | |
108 | ||
109 | /* Now initialize the filter; we pass NULL options, since we have already | |
110 | * set all the options above. */ | |
111 | err = avfilter_init_str(abuffer_ctx, NULL); | |
112 | if (err < 0) { | |
113 | fprintf(stderr, "Could not initialize the abuffer filter.\n"); | |
114 | return err; | |
115 | } | |
116 | ||
117 | /* Create volume filter. */ | |
118 | volume = avfilter_get_by_name("volume"); | |
119 | if (!volume) { | |
120 | fprintf(stderr, "Could not find the volume filter.\n"); | |
121 | return AVERROR_FILTER_NOT_FOUND; | |
122 | } | |
123 | ||
124 | volume_ctx = avfilter_graph_alloc_filter(filter_graph, volume, "volume"); | |
125 | if (!volume_ctx) { | |
126 | fprintf(stderr, "Could not allocate the volume instance.\n"); | |
127 | return AVERROR(ENOMEM); | |
128 | } | |
129 | ||
130 | /* A different way of passing the options is as key/value pairs in a | |
131 | * dictionary. */ | |
132 | av_dict_set(&options_dict, "volume", AV_STRINGIFY(VOLUME_VAL), 0); | |
133 | err = avfilter_init_dict(volume_ctx, &options_dict); | |
134 | av_dict_free(&options_dict); | |
135 | if (err < 0) { | |
136 | fprintf(stderr, "Could not initialize the volume filter.\n"); | |
137 | return err; | |
138 | } | |
139 | ||
140 | /* Create the aformat filter; | |
141 | * it ensures that the output is of the format we want. */ | |
142 | aformat = avfilter_get_by_name("aformat"); | |
143 | if (!aformat) { | |
144 | fprintf(stderr, "Could not find the aformat filter.\n"); | |
145 | return AVERROR_FILTER_NOT_FOUND; | |
146 | } | |
147 | ||
148 | aformat_ctx = avfilter_graph_alloc_filter(filter_graph, aformat, "aformat"); | |
149 | if (!aformat_ctx) { | |
150 | fprintf(stderr, "Could not allocate the aformat instance.\n"); | |
151 | return AVERROR(ENOMEM); | |
152 | } | |
153 | ||
154 | /* A third way of passing the options is in a string of the form | |
155 | * key1=value1:key2=value2.... */ | |
156 | snprintf(options_str, sizeof(options_str), | |
157 | "sample_fmts=%s:sample_rates=%d:channel_layouts=0x%"PRIx64, | |
158 | av_get_sample_fmt_name(AV_SAMPLE_FMT_S16), 44100, | |
159 | (uint64_t)AV_CH_LAYOUT_STEREO); | |
160 | err = avfilter_init_str(aformat_ctx, options_str); | |
161 | if (err < 0) { | |
162 | av_log(NULL, AV_LOG_ERROR, "Could not initialize the aformat filter.\n"); | |
163 | return err; | |
164 | } | |
165 | ||
166 | /* Finally create the abuffersink filter; | |
167 | * it will be used to get the filtered data out of the graph. */ | |
168 | abuffersink = avfilter_get_by_name("abuffersink"); | |
169 | if (!abuffersink) { | |
170 | fprintf(stderr, "Could not find the abuffersink filter.\n"); | |
171 | return AVERROR_FILTER_NOT_FOUND; | |
172 | } | |
173 | ||
174 | abuffersink_ctx = avfilter_graph_alloc_filter(filter_graph, abuffersink, "sink"); | |
175 | if (!abuffersink_ctx) { | |
176 | fprintf(stderr, "Could not allocate the abuffersink instance.\n"); | |
177 | return AVERROR(ENOMEM); | |
178 | } | |
179 | ||
180 | /* This filter takes no options. */ | |
181 | err = avfilter_init_str(abuffersink_ctx, NULL); | |
182 | if (err < 0) { | |
183 | fprintf(stderr, "Could not initialize the abuffersink instance.\n"); | |
184 | return err; | |
185 | } | |
186 | ||
187 | /* Connect the filters; | |
188 | * in this simple case the filters just form a linear chain. */ | |
189 | err = avfilter_link(abuffer_ctx, 0, volume_ctx, 0); | |
190 | if (err >= 0) | |
191 | err = avfilter_link(volume_ctx, 0, aformat_ctx, 0); | |
192 | if (err >= 0) | |
193 | err = avfilter_link(aformat_ctx, 0, abuffersink_ctx, 0); | |
194 | if (err < 0) { | |
195 | fprintf(stderr, "Error connecting filters\n"); | |
196 | return err; | |
197 | } | |
198 | ||
199 | /* Configure the graph. */ | |
200 | err = avfilter_graph_config(filter_graph, NULL); | |
201 | if (err < 0) { | |
202 | av_log(NULL, AV_LOG_ERROR, "Error configuring the filter graph\n"); | |
203 | return err; | |
204 | } | |
205 | ||
206 | *graph = filter_graph; | |
207 | *src = abuffer_ctx; | |
208 | *sink = abuffersink_ctx; | |
209 | ||
210 | return 0; | |
211 | } | |
212 | ||
213 | /* Do something useful with the filtered data: this simple | |
214 | * example just prints the MD5 checksum of each plane to stdout. */ | |
215 | static int process_output(struct AVMD5 *md5, AVFrame *frame) | |
216 | { | |
217 | int planar = av_sample_fmt_is_planar(frame->format); | |
218 | int channels = av_get_channel_layout_nb_channels(frame->channel_layout); | |
219 | int planes = planar ? channels : 1; | |
220 | int bps = av_get_bytes_per_sample(frame->format); | |
221 | int plane_size = bps * frame->nb_samples * (planar ? 1 : channels); | |
222 | int i, j; | |
223 | ||
224 | for (i = 0; i < planes; i++) { | |
225 | uint8_t checksum[16]; | |
226 | ||
227 | av_md5_init(md5); | |
228 | av_md5_sum(checksum, frame->extended_data[i], plane_size); | |
229 | ||
230 | fprintf(stdout, "plane %d: 0x", i); | |
231 | for (j = 0; j < sizeof(checksum); j++) | |
232 | fprintf(stdout, "%02X", checksum[j]); | |
233 | fprintf(stdout, "\n"); | |
234 | } | |
235 | fprintf(stdout, "\n"); | |
236 | ||
237 | return 0; | |
238 | } | |
239 | ||
240 | /* Construct a frame of audio data to be filtered; | |
241 | * this simple example just synthesizes a sine wave. */ | |
242 | static int get_input(AVFrame *frame, int frame_num) | |
243 | { | |
244 | int err, i, j; | |
245 | ||
246 | #define FRAME_SIZE 1024 | |
247 | ||
248 | /* Set up the frame properties and allocate the buffer for the data. */ | |
249 | frame->sample_rate = INPUT_SAMPLERATE; | |
250 | frame->format = INPUT_FORMAT; | |
251 | frame->channel_layout = INPUT_CHANNEL_LAYOUT; | |
252 | frame->nb_samples = FRAME_SIZE; | |
253 | frame->pts = frame_num * FRAME_SIZE; | |
254 | ||
255 | err = av_frame_get_buffer(frame, 0); | |
256 | if (err < 0) | |
257 | return err; | |
258 | ||
259 | /* Fill the data for each channel. */ | |
260 | for (i = 0; i < 5; i++) { | |
261 | float *data = (float*)frame->extended_data[i]; | |
262 | ||
263 | for (j = 0; j < frame->nb_samples; j++) | |
264 | data[j] = sin(2 * M_PI * (frame_num + j) * (i + 1) / FRAME_SIZE); | |
265 | } | |
266 | ||
267 | return 0; | |
268 | } | |
269 | ||
270 | int main(int argc, char *argv[]) | |
271 | { | |
272 | struct AVMD5 *md5; | |
273 | AVFilterGraph *graph; | |
274 | AVFilterContext *src, *sink; | |
275 | AVFrame *frame; | |
276 | uint8_t errstr[1024]; | |
277 | float duration; | |
278 | int err, nb_frames, i; | |
279 | ||
280 | if (argc < 2) { | |
281 | fprintf(stderr, "Usage: %s <duration>\n", argv[0]); | |
282 | return 1; | |
283 | } | |
284 | ||
285 | duration = atof(argv[1]); | |
286 | nb_frames = duration * INPUT_SAMPLERATE / FRAME_SIZE; | |
287 | if (nb_frames <= 0) { | |
288 | fprintf(stderr, "Invalid duration: %s\n", argv[1]); | |
289 | return 1; | |
290 | } | |
291 | ||
292 | avfilter_register_all(); | |
293 | ||
294 | /* Allocate the frame we will be using to store the data. */ | |
295 | frame = av_frame_alloc(); | |
296 | if (!frame) { | |
297 | fprintf(stderr, "Error allocating the frame\n"); | |
298 | return 1; | |
299 | } | |
300 | ||
301 | md5 = av_md5_alloc(); | |
302 | if (!md5) { | |
303 | fprintf(stderr, "Error allocating the MD5 context\n"); | |
304 | return 1; | |
305 | } | |
306 | ||
307 | /* Set up the filtergraph. */ | |
308 | err = init_filter_graph(&graph, &src, &sink); | |
309 | if (err < 0) { | |
310 | fprintf(stderr, "Unable to init filter graph:"); | |
311 | goto fail; | |
312 | } | |
313 | ||
314 | /* the main filtering loop */ | |
315 | for (i = 0; i < nb_frames; i++) { | |
316 | /* get an input frame to be filtered */ | |
317 | err = get_input(frame, i); | |
318 | if (err < 0) { | |
319 | fprintf(stderr, "Error generating input frame:"); | |
320 | goto fail; | |
321 | } | |
322 | ||
323 | /* Send the frame to the input of the filtergraph. */ | |
324 | err = av_buffersrc_add_frame(src, frame); | |
325 | if (err < 0) { | |
326 | av_frame_unref(frame); | |
327 | fprintf(stderr, "Error submitting the frame to the filtergraph:"); | |
328 | goto fail; | |
329 | } | |
330 | ||
331 | /* Get all the filtered output that is available. */ | |
332 | while ((err = av_buffersink_get_frame(sink, frame)) >= 0) { | |
333 | /* now do something with our filtered frame */ | |
334 | err = process_output(md5, frame); | |
335 | if (err < 0) { | |
336 | fprintf(stderr, "Error processing the filtered frame:"); | |
337 | goto fail; | |
338 | } | |
339 | av_frame_unref(frame); | |
340 | } | |
341 | ||
342 | if (err == AVERROR(EAGAIN)) { | |
343 | /* Need to feed more frames in. */ | |
344 | continue; | |
345 | } else if (err == AVERROR_EOF) { | |
346 | /* Nothing more to do, finish. */ | |
347 | break; | |
348 | } else if (err < 0) { | |
349 | /* An error occurred. */ | |
350 | fprintf(stderr, "Error filtering the data:"); | |
351 | goto fail; | |
352 | } | |
353 | } | |
354 | ||
355 | avfilter_graph_free(&graph); | |
356 | av_frame_free(&frame); | |
357 | av_freep(&md5); | |
358 | ||
359 | return 0; | |
360 | ||
361 | fail: | |
362 | av_strerror(err, errstr, sizeof(errstr)); | |
363 | fprintf(stderr, "%s\n", errstr); | |
364 | return 1; | |
365 | } |