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
27 #include "avfiltergraph.h"
32 static const char *log_name(void *p)
34 return "Filter parser";
37 static const AVClass filter_parser_class = {
42 static const AVClass *log_ctx = &filter_parser_class;
44 void avfilter_destroy_graph(AVFilterGraph *graph)
46 for(; graph->filter_count > 0; graph->filter_count --)
47 avfilter_destroy(graph->filters[graph->filter_count - 1]);
48 av_freep(&graph->filters);
51 /* TODO: insert in sorted order */
52 void avfilter_graph_add_filter(AVFilterGraph *graph, AVFilterContext *filter)
54 graph->filters = av_realloc(graph->filters,
55 sizeof(AVFilterContext*) * ++graph->filter_count);
56 graph->filters[graph->filter_count - 1] = filter;
59 /* search intelligently, once we insert in order */
60 AVFilterContext *avfilter_graph_get_filter(AVFilterGraph *graph, char *name)
67 for(i = 0; i < graph->filter_count; i ++)
68 if(graph->filters[i]->name && !strcmp(name, graph->filters[i]->name))
69 return graph->filters[i];
74 static int query_formats(AVFilterGraph *graph)
78 /* ask all the sub-filters for their supported colorspaces */
79 for(i = 0; i < graph->filter_count; i ++) {
80 if(graph->filters[i]->filter->query_formats)
81 graph->filters[i]->filter->query_formats(graph->filters[i]);
83 avfilter_default_query_formats(graph->filters[i]);
86 /* go through and merge as many format lists as possible */
87 for(i = 0; i < graph->filter_count; i ++) {
88 AVFilterContext *filter = graph->filters[i];
90 for(j = 0; j < filter->input_count; j ++) {
92 if(!(link = filter->inputs[j]))
94 if(link->in_formats != link->out_formats) {
95 if(!avfilter_merge_formats(link->in_formats,
97 /* couldn't merge format lists. auto-insert scale filter */
98 AVFilterContext *scale;
101 avfilter_open(avfilter_get_by_name("scale"), NULL)))
103 if(scale->filter->init(scale, NULL, NULL) ||
104 avfilter_insert_filter(link, scale, 0, 0)) {
105 avfilter_destroy(scale);
109 avfilter_graph_add_filter(graph, scale);
110 scale->filter->query_formats(scale);
111 if(!avfilter_merge_formats(scale-> inputs[0]->in_formats,
112 scale-> inputs[0]->out_formats) ||
113 !avfilter_merge_formats(scale->outputs[0]->in_formats,
114 scale->outputs[0]->out_formats))
124 static void pick_format(AVFilterLink *link)
126 if(!link || !link->in_formats)
129 link->in_formats->format_count = 1;
130 link->format = link->in_formats->formats[0];
132 avfilter_formats_unref(&link->in_formats);
133 avfilter_formats_unref(&link->out_formats);
136 static void pick_formats(AVFilterGraph *graph)
140 for(i = 0; i < graph->filter_count; i ++) {
141 AVFilterContext *filter = graph->filters[i];
143 for(j = 0; j < filter->input_count; j ++)
144 pick_format(filter->inputs[j]);
145 for(j = 0; j < filter->output_count; j ++)
146 pick_format(filter->outputs[j]);
150 int avfilter_graph_config_formats(AVFilterGraph *graph)
152 /* find supported formats from sub-filters, and merge along links */
153 if(query_formats(graph))
156 /* Once everything is merged, it's possible that we'll still have
157 * multiple valid colorspace choices. We pick the first one. */
163 static int create_filter(AVFilterGraph *ctx, int index, char *name,
166 AVFilterContext *filt;
171 snprintf(tmp, 20, "%d", index);
172 if(!(filterdef = avfilter_get_by_name(name)) ||
173 !(filt = avfilter_open(filterdef, tmp))) {
174 av_log(&log_ctx, AV_LOG_ERROR,
175 "error creating filter '%s'\n", name);
178 avfilter_graph_add_filter(ctx, filt);
179 if(avfilter_init_filter(filt, args, NULL)) {
180 av_log(&log_ctx, AV_LOG_ERROR,
181 "error initializing filter '%s'\n", name);
188 static int link_filter(AVFilterGraph *ctx, int src, int srcpad,
191 AVFilterContext *filt, *filtb;
195 snprintf(tmp, 20, "%d", src);
196 if(!(filt = avfilter_graph_get_filter(ctx, tmp))) {
197 av_log(&log_ctx, AV_LOG_ERROR, "link source does not exist in graph\n");
200 snprintf(tmp, 20, "%d", dst);
201 if(!(filtb = avfilter_graph_get_filter(ctx, tmp))) {
202 av_log(&log_ctx, AV_LOG_ERROR, "link destination does not exist in graph\n");
205 if(avfilter_link(filt, srcpad, filtb, dstpad)) {
206 av_log(&log_ctx, AV_LOG_ERROR, "cannot create link between source and destination filters\n");
213 static void consume_whitespace(const char **buf)
215 *buf += strspn(*buf, " \n\t");
219 * get the next non-whitespace char
221 static char consume_char(const char **buf)
224 consume_whitespace(buf);
235 * Copy the first size bytes of input string to a null-terminated string,
236 * removing any control character. Ex: "aaa'bb'c\'c\\" -> "aaabbc'c\"
238 static void copy_unquoted(char *out, const char *in, int size)
241 for (i=0; i < size; i++) {
244 else if (in[i] == '\\') {
257 * Consumes a string from *buf.
258 * @return a copy of the consumed string, which should be free'd after use
260 static char *consume_string(const char **buf)
266 consume_whitespace(buf);
269 return av_mallocz(1);
274 *buf += strcspn(*buf, " ()=,'\\");
282 const char *p = *buf;
286 } while (p && p[-1] == '\\');
290 *buf += strlen(*buf); // Move the pointer to the null end byte
293 size = *buf - start + 1;
294 ret = av_malloc(size);
295 copy_unquoted(ret, start, size-1);
302 * @arg name a pointer (that need to be free'd after use) to the name between
305 static void parse_link_name(const char **buf, char **name)
309 *name = consume_string(buf);
314 if (consume_char(buf) != ')')
320 av_log(&log_ctx, AV_LOG_ERROR, "Could not parse link name!\n");
324 * Parse "filter=params"
325 * @arg name a pointer (that need to be free'd after use) to the name of the
327 * @arg ars a pointer (that need to be free'd after use) to the args of the
330 static int parse_filter(const char **buf, AVFilterGraph *graph, int index)
333 name = consume_string(buf);
337 opts = consume_string(buf);
342 return create_filter(graph, index, name, opts);
351 * A linked-list of the inputs/outputs of the filter chain.
353 typedef struct AVFilterInOut {
359 struct AVFilterInOut *next;
362 static void free_inout(AVFilterInOut *head)
373 * Parse "(a1)(link2) ... (etc)"
375 static int parse_inouts(const char **buf, AVFilterInOut **inout, int firstpad,
376 enum LinkType type, int instance)
379 while (**buf == '(') {
380 AVFilterInOut *inoutn = av_malloc(sizeof(AVFilterInOut));
381 parse_link_name(buf, &inoutn->name);
383 inoutn->instance = instance;
384 inoutn->pad_idx = pad++;
385 inoutn->next = *inout;
392 * Parse a string describing a filter graph.
394 int avfilter_graph_parse_chain(AVFilterGraph *graph, const char *filters, AVFilterContext *in, int inpad, AVFilterContext *out, int outpad)
396 AVFilterInOut *inout=NULL;
397 AVFilterInOut *head=NULL;
405 AVFilterContext *filt;
407 consume_whitespace(&filters);
412 pad = parse_inouts(&filters, &inout, chr == ',', LinkTypeIn, index);
414 if (parse_filter(&filters, graph, index) < 0)
417 // If the first filter has an input and none was given, it is
418 // implicitly the input of the whole graph.
419 if (pad == 0 && graph->filters[graph->filter_count-1]->input_count == 1) {
420 snprintf(tmp, 20, "%d", index);
421 if(!(filt = avfilter_graph_get_filter(graph, tmp))) {
422 av_log(&log_ctx, AV_LOG_ERROR, "filter owning exported pad does not exist\n");
425 if(avfilter_link(in, inpad, filt, 0)) {
426 av_log(&log_ctx, AV_LOG_ERROR, "cannot create link between source and destination filters\n");
432 if (link_filter(graph, index-1, oldpad, index, 0) < 0)
436 pad = parse_inouts(&filters, &inout, 0, LinkTypeOut, index);
437 chr = consume_char(&filters);
439 } while (chr == ',' || chr == ';');
442 for (; inout != NULL; inout = inout->next) {
443 if (inout->instance == -1)
444 continue; // Already processed
446 if (!strcmp(inout->name, "in")) {
447 snprintf(tmp, 20, "%d", inout->instance);
448 if(!(filt = avfilter_graph_get_filter(graph, tmp))) {
449 av_log(&log_ctx, AV_LOG_ERROR, "filter owning exported pad does not exist\n");
452 if(avfilter_link(in, inpad, filt, inout->pad_idx)) {
453 av_log(&log_ctx, AV_LOG_ERROR, "cannot create link between source and destination filters\n");
456 } else if (!strcmp(inout->name, "out")) {
458 snprintf(tmp, 20, "%d", inout->instance);
459 if(!(filt = avfilter_graph_get_filter(graph, tmp))) {
460 av_log(&log_ctx, AV_LOG_ERROR, "filter owning exported pad does not exist\n");
464 if(avfilter_link(filt, inout->pad_idx, out, outpad)) {
465 av_log(&log_ctx, AV_LOG_ERROR, "cannot create link between source and destination filters\n");
470 AVFilterInOut *p, *src, *dst;
471 for (p = inout->next;
472 p && strcmp(p->name,inout->name); p = p->next);
475 av_log(&log_ctx, AV_LOG_ERROR, "Unmatched link: %s.\n",
480 if (p->type == LinkTypeIn && inout->type == LinkTypeOut) {
483 } else if (p->type == LinkTypeOut && inout->type == LinkTypeIn) {
487 av_log(&log_ctx, AV_LOG_ERROR, "Two links named '%s' are either both input or both output\n",
492 if (link_filter(graph, src->instance, src->pad_idx, dst->instance, dst->pad_idx) < 0)
503 snprintf(tmp, 20, "%d", index-1);
504 if(!(filt = avfilter_graph_get_filter(graph, tmp))) {
505 av_log(&log_ctx, AV_LOG_ERROR, "filter owning exported pad does not exist\n");
509 if(avfilter_link(filt, pad, out, outpad)) {
510 av_log(&log_ctx, AV_LOG_ERROR, "cannot create link between source and destination filters\n");
520 avfilter_destroy_graph(graph);