Libav
graph2dot.c
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1 /*
2  * Copyright (c) 2008-2010 Stefano Sabatini
3  *
4  * This file is part of Libav.
5  *
6  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include "config.h"
22 #if HAVE_UNISTD_H
23 #include <unistd.h> /* getopt */
24 #endif
25 #include <stdio.h>
26 #include <string.h>
27 
29 #include "libavutil/mem.h"
30 #include "libavutil/pixdesc.h"
31 #include "libavutil/audioconvert.h"
32 #include "libavfilter/avfilter.h"
33 
34 #if !HAVE_GETOPT
35 #include "compat/getopt.c"
36 #endif
37 
38 static void usage(void)
39 {
40  printf("Convert a libavfilter graph to a dot file.\n");
41  printf("Usage: graph2dot [OPTIONS]\n");
42  printf("\n"
43  "Options:\n"
44  "-i INFILE set INFILE as input file, stdin if omitted\n"
45  "-o OUTFILE set OUTFILE as output file, stdout if omitted\n"
46  "-h print this help\n");
47 }
48 
49 struct line {
50  char data[256];
51  struct line *next;
52 };
53 
54 static void print_digraph(FILE *outfile, AVFilterGraph *graph)
55 {
56  int i, j;
57 
58  fprintf(outfile, "digraph G {\n");
59  fprintf(outfile, "node [shape=box]\n");
60  fprintf(outfile, "rankdir=LR\n");
61 
62  for (i = 0; i < graph->nb_filters; i++) {
63  char filter_ctx_label[128];
64  const AVFilterContext *filter_ctx = graph->filters[i];
65 
66  snprintf(filter_ctx_label, sizeof(filter_ctx_label), "%s (%s)",
67  filter_ctx->name,
68  filter_ctx->filter->name);
69 
70  for (j = 0; j < filter_ctx->nb_outputs; j++) {
71  AVFilterLink *link = filter_ctx->outputs[j];
72  if (link) {
73  char dst_filter_ctx_label[128];
74  const AVFilterContext *dst_filter_ctx = link->dst;
75 
76  snprintf(dst_filter_ctx_label, sizeof(dst_filter_ctx_label),
77  "%s (%s)",
78  dst_filter_ctx->name,
79  dst_filter_ctx->filter->name);
80 
81  fprintf(outfile, "\"%s\" -> \"%s\"",
82  filter_ctx_label, dst_filter_ctx_label);
83  if (link->type == AVMEDIA_TYPE_VIDEO) {
84  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format);
85  fprintf(outfile,
86  " [ label= \"fmt:%s w:%d h:%d tb:%d/%d\" ]",
87  desc->name, link->w, link->h, link->time_base.num,
88  link->time_base.den);
89  } else if (link->type == AVMEDIA_TYPE_AUDIO) {
90  char buf[255];
91  av_get_channel_layout_string(buf, sizeof(buf), -1,
92  link->channel_layout);
93  fprintf(outfile,
94  " [ label= \"fmt:%s sr:%d cl:%s\" ]",
96  link->sample_rate, buf);
97  }
98  fprintf(outfile, ";\n");
99  }
100  }
101  }
102  fprintf(outfile, "}\n");
103 }
104 
105 int main(int argc, char **argv)
106 {
107  const char *outfilename = NULL;
108  const char *infilename = NULL;
109  FILE *outfile = NULL;
110  FILE *infile = NULL;
111  char *graph_string = NULL;
112  AVFilterGraph *graph = av_mallocz(sizeof(AVFilterGraph));
113  char c;
114 
116 
117  while ((c = getopt(argc, argv, "hi:o:")) != -1) {
118  switch (c) {
119  case 'h':
120  usage();
121  return 0;
122  case 'i':
123  infilename = optarg;
124  break;
125  case 'o':
126  outfilename = optarg;
127  break;
128  case '?':
129  return 1;
130  }
131  }
132 
133  if (!infilename || !strcmp(infilename, "-"))
134  infilename = "/dev/stdin";
135  infile = fopen(infilename, "r");
136  if (!infile) {
137  fprintf(stderr, "Failed to open input file '%s': %s\n",
138  infilename, strerror(errno));
139  return 1;
140  }
141 
142  if (!outfilename || !strcmp(outfilename, "-"))
143  outfilename = "/dev/stdout";
144  outfile = fopen(outfilename, "w");
145  if (!outfile) {
146  fprintf(stderr, "Failed to open output file '%s': %s\n",
147  outfilename, strerror(errno));
148  return 1;
149  }
150 
151  /* read from infile and put it in a buffer */
152  {
153  unsigned int count = 0;
154  struct line *line, *last_line, *first_line;
155  char *p;
156  last_line = first_line = av_malloc(sizeof(struct line));
157 
158  while (fgets(last_line->data, sizeof(last_line->data), infile)) {
159  struct line *new_line = av_malloc(sizeof(struct line));
160  count += strlen(last_line->data);
161  last_line->next = new_line;
162  last_line = new_line;
163  }
164  last_line->next = NULL;
165 
166  graph_string = av_malloc(count + 1);
167  p = graph_string;
168  for (line = first_line; line->next; line = line->next) {
169  unsigned int l = strlen(line->data);
170  memcpy(p, line->data, l);
171  p += l;
172  }
173  *p = '\0';
174  }
175 
177 
178  if (avfilter_graph_parse(graph, graph_string, NULL, NULL, NULL) < 0) {
179  fprintf(stderr, "Failed to parse the graph description\n");
180  return 1;
181  }
182 
183  if (avfilter_graph_config(graph, NULL) < 0)
184  return 1;
185 
186  print_digraph(outfile, graph);
187  fflush(outfile);
188 
189  return 0;
190 }