3 * copyright (c) 2008 Vitor Sessak
4 * copyright (c) 2007 Bobby Bingham
6 * This file is part of FFmpeg.
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26 #include "graphparser.h"
28 #include "avfiltergraph.h"
30 static int link_filter(AVFilterContext *src, int srcpad,
31 AVFilterContext *dst, int dstpad,
34 if(avfilter_link(src, srcpad, dst, dstpad)) {
35 av_log(log_ctx, AV_LOG_ERROR,
36 "cannot create the link %s:%d -> %s:%d\n",
37 src->filter->name, srcpad, dst->filter->name, dstpad);
44 static int consume_whitespace(const char *buf)
46 return strspn(buf, " \n\t");
50 * Consumes a string from *buf.
51 * @return a copy of the consumed string, which should be free'd after use
53 static char *consume_string(const char **buf)
55 char *out = av_malloc(strlen(*buf) + 1);
58 *buf += consume_whitespace(*buf);
67 while(**buf && **buf != '\'')
87 *buf += consume_whitespace(*buf);
94 * @param name a pointer (that need to be free'd after use) to the name between
97 static char *parse_link_name(const char **buf, AVClass *log_ctx)
99 const char *start = *buf;
103 name = consume_string(buf);
106 av_log(log_ctx, AV_LOG_ERROR,
107 "Bad (empty?) label found in the following: \"%s\".\n", start);
111 if(*(*buf)++ != ']') {
112 av_log(log_ctx, AV_LOG_ERROR,
113 "Mismatched '[' found in the following: \"%s\".\n", start);
121 static AVFilterContext *create_filter(AVFilterGraph *ctx, int index,
122 const char *name, const char *args,
125 AVFilterContext *filt;
130 snprintf(inst_name, sizeof(inst_name), "Parsed filter %d", index);
132 filterdef = avfilter_get_by_name(name);
135 av_log(log_ctx, AV_LOG_ERROR,
136 "no such filter: '%s'\n", name);
140 filt = avfilter_open(filterdef, inst_name);
142 av_log(log_ctx, AV_LOG_ERROR,
143 "error creating filter '%s'\n", name);
147 if(avfilter_graph_add_filter(ctx, filt) < 0) {
148 avfilter_destroy(filt);
152 if(avfilter_init_filter(filt, args, NULL)) {
153 av_log(log_ctx, AV_LOG_ERROR,
154 "error initializing filter '%s' with args '%s'\n", name, args);
162 * Parse "filter=params"
164 static AVFilterContext *parse_filter(const char **buf, AVFilterGraph *graph,
165 int index, AVClass *log_ctx)
168 char *name = consume_string(buf);
169 AVFilterContext *ret;
173 opts = consume_string(buf);
176 ret = create_filter(graph, index, name, opts, log_ctx);
182 static void free_inout(AVFilterInOut *head)
185 AVFilterInOut *next = head->next;
192 static AVFilterInOut *extract_inout(const char *label, AVFilterInOut **links)
196 while(*links && strcmp((*links)->name, label))
197 links = &((*links)->next);
207 static void insert_inout(AVFilterInOut **inouts, AVFilterInOut *element)
209 element->next = *inouts;
213 static int link_filter_inouts(AVFilterContext *filter,
214 AVFilterInOut **currInputs,
215 AVFilterInOut **openLinks, AVClass *log_ctx)
217 int pad = filter->input_count;
220 AVFilterInOut *p = *currInputs;
222 av_log(log_ctx, AV_LOG_ERROR,
223 "Not enough inputs specified for the \"%s\" filter.\n",
224 filter->filter->name);
228 *currInputs = (*currInputs)->next;
231 if(link_filter(p->filter, p->pad_idx, filter, pad, log_ctx))
238 insert_inout(openInputs, p);
243 av_log(log_ctx, AV_LOG_ERROR,
244 "Too many inputs specified for the \"%s\" filter.\n",
245 filter->filter->name);
249 pad = filter->output_count;
251 AVFilterInOut *currlinkn = av_mallocz(sizeof(AVFilterInOut));
252 currlinkn->type = LinkTypeOut;
253 currlinkn->filter = filter;
254 currlinkn->pad_idx = pad;
255 insert_inout(currInputs, currlinkn);
261 static int parse_inputs(const char **buf, AVFilterInOut **currInputs,
262 AVFilterInOut **openLinks, AVClass *log_ctx)
266 while(**buf == '[') {
267 char *name = parse_link_name(buf, log_ctx);
268 AVFilterInOut *match;
273 /* First check if the label is not in the openLinks list */
274 match = extract_inout(name, openLinks);
277 /* A label of a open link. Make it one of the inputs of the next
279 if(match->type != LinkTypeOut) {
280 av_log(log_ctx, AV_LOG_ERROR,
281 "Label \"%s\" appears twice as input!\n", match->name);
285 /* Not in the list, so add it as an input */
286 match = av_mallocz(sizeof(AVFilterInOut));
288 match->type = LinkTypeIn;
289 match->pad_idx = pad;
292 insert_inout(currInputs, match);
294 *buf += consume_whitespace(*buf);
301 static int parse_outputs(const char **buf, AVFilterInOut **currInputs,
302 AVFilterInOut **openLinks, AVClass *log_ctx)
306 while(**buf == '[') {
307 char *name = parse_link_name(buf, log_ctx);
308 AVFilterInOut *match;
310 AVFilterInOut *input = *currInputs;
311 *currInputs = (*currInputs)->next;
316 /* First check if the label is not in the openLinks list */
317 match = extract_inout(name, openLinks);
320 /* A label of a open link. Link it. */
321 if(match->type != LinkTypeIn) {
322 av_log(log_ctx, AV_LOG_ERROR,
323 "Label \"%s\" appears twice as output!\n", match->name);
327 if(link_filter(input->filter, input->pad_idx,
328 match->filter, match->pad_idx, log_ctx) < 0)
330 av_free(match->name);
335 /* Not in the list, so add the first input as a openLink */
336 input->next = *openLinks;
337 input->type = LinkTypeOut;
339 insert_inout(openOutputs, input);
341 *buf += consume_whitespace(*buf);
348 int avfilter_parse_graph(AVFilterGraph *graph, const char *filters,
349 AVFilterInOut *openLinks, AVClass *log_ctx)
354 AVFilterInOut *currInputs = NULL;
357 AVFilterContext *filter;
358 filters += consume_whitespace(filters);
360 if(parse_inputs(&filters, &currInputs, &openLinks, log_ctx) < 0)
363 filter = parse_filter(&filters, graph, index, log_ctx);
368 if(filter->input_count == 1 && !currInputs && !index) {
369 /* First input can be ommitted if it is "[in]" */
370 const char *tmp = "[in]";
371 if(parse_inputs(&tmp, &currInputs, &openLinks, log_ctx))
375 if(link_filter_inouts(filter, &currInputs, &openLinks, log_ctx) < 0)
378 if(parse_outputs(&filters, &currInputs, &openLinks, log_ctx))
381 filters += consume_whitespace(filters);
384 if(chr == ';' && currInputs) {
385 av_log(log_ctx, AV_LOG_ERROR,
386 "Could not find a output to link when parsing \"%s\"\n",
391 } while(chr == ',' || chr == ';');
393 if(openLinks && !strcmp(openLinks->name, "out") && currInputs) {
394 /* Last output can be ommitted if it is "[out]" */
395 const char *tmp = "[out]";
396 if(parse_outputs(&tmp, &currInputs, &openLinks, log_ctx) < 0)
403 avfilter_destroy_graph(graph);
404 free_inout(openLinks);
405 free_inout(currInputs);