filtfmts.c
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1 /*
2  * Copyright (c) 2009 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 <stdio.h>
22 
23 #include "libavformat/avformat.h"
24 #include "libavutil/pixdesc.h"
25 #include "libavfilter/avfilter.h"
26 #include "libavfilter/formats.h"
27 
28 int main(int argc, char **argv)
29 {
31  AVFilterContext *filter_ctx;
32  const char *filter_name;
33  const char *filter_args = NULL;
34  int i, j;
35 
37 
38  if (!argv[1]) {
39  fprintf(stderr, "Missing filter name as argument\n");
40  return 1;
41  }
42 
43  filter_name = argv[1];
44  if (argv[2])
45  filter_args = argv[2];
46 
48 
49  /* get a corresponding filter and open it */
50  if (!(filter = avfilter_get_by_name(filter_name))) {
51  fprintf(stderr, "Unrecognized filter with name '%s'\n", filter_name);
52  return 1;
53  }
54 
55  if (avfilter_open(&filter_ctx, filter, NULL) < 0) {
56  fprintf(stderr, "Impossible to open filter with name '%s'\n",
57  filter_name);
58  return 1;
59  }
60  if (avfilter_init_filter(filter_ctx, filter_args, NULL) < 0) {
61  fprintf(stderr, "Impossible to init filter '%s' with arguments '%s'\n",
62  filter_name, filter_args);
63  return 1;
64  }
65 
66  /* create a link for each of the input pads */
67  for (i = 0; i < filter_ctx->input_count; i++) {
68  AVFilterLink *link = av_mallocz(sizeof(AVFilterLink));
69  link->type = filter_ctx->filter->inputs[i].type;
70  filter_ctx->inputs[i] = link;
71  }
72  for (i = 0; i < filter_ctx->output_count; i++) {
73  AVFilterLink *link = av_mallocz(sizeof(AVFilterLink));
74  link->type = filter_ctx->filter->outputs[i].type;
75  filter_ctx->outputs[i] = link;
76  }
77 
78  if (filter->query_formats)
79  filter->query_formats(filter_ctx);
80  else
81  ff_default_query_formats(filter_ctx);
82 
83  /* print the supported formats in input */
84  for (i = 0; i < filter_ctx->input_count; i++) {
85  AVFilterFormats *fmts = filter_ctx->inputs[i]->out_formats;
86  for (j = 0; j < fmts->format_count; j++)
87  printf("INPUT[%d] %s: %s\n",
88  i, filter_ctx->filter->inputs[i].name,
89  av_get_pix_fmt_name(fmts->formats[j]));
90  }
91 
92  /* print the supported formats in output */
93  for (i = 0; i < filter_ctx->output_count; i++) {
94  AVFilterFormats *fmts = filter_ctx->outputs[i]->in_formats;
95  for (j = 0; j < fmts->format_count; j++)
96  printf("OUTPUT[%d] %s: %s\n",
97  i, filter_ctx->filter->outputs[i].name,
98  av_get_pix_fmt_name(fmts->formats[j]));
99  }
100 
101  avfilter_free(filter_ctx);
102  fflush(stdout);
103  return 0;
104 }
void avfilter_register_all(void)
Initialize the filter system.
Definition: allfilters.c:39
static const char * filter_name(void *p)
Definition: avfilter.c:316
void avfilter_free(AVFilterContext *filter)
Free a filter context.
Definition: avfilter.c:391
enum AVMediaType type
AVFilterPad type.
Definition: internal.h:44
int(* query_formats)(AVFilterContext *)
Queries formats supported by the filter and its pads, and sets the in_formats for links connected to ...
Definition: avfilter.h:412
const char * name
Pad name.
Definition: internal.h:39
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:426
int avfilter_init_filter(AVFilterContext *filter, const char *args, void *opaque)
Initialize a filter.
Definition: avfilter.c:435
AVFilter * avfilter_get_by_name(const char *name)
Get a filter definition matching the given name.
Definition: avfilter.c:274
void av_log_set_level(int level)
Definition: log.c:168
static void filter(MpegAudioContext *s, int ch, const short *samples, int incr)
Definition: mpegaudioenc.c:318
int avfilter_open(AVFilterContext **filter_ctx, AVFilter *filter, const char *inst_name)
Create a filter instance.
Definition: avfilter.c:329
const AVFilterPad * inputs
NULL terminated list of inputs. NULL if none.
Definition: avfilter.h:380
int ff_default_query_formats(AVFilterContext *ctx)
Definition: formats.c:381
NULL
Definition: eval.c:52
Filter definition.
Definition: avfilter.h:371
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:433
Main libavformat public API header.
AVFilter * filter
the AVFilter of which this is an instance
Definition: avfilter.h:421
int main(int argc, char **argv)
Definition: filtfmts.c:28
A list of supported formats for one end of a filter link.
Definition: formats.h:64
An instance of a filter.
Definition: avfilter.h:418
const AVFilterPad * outputs
NULL terminated list of outputs. NULL if none.
Definition: avfilter.h:381
const char * av_get_pix_fmt_name(enum AVPixelFormat pix_fmt)
Return the short name for a pixel format, NULL in case pix_fmt is unknown.
Definition: pixdesc.c:1377
void * av_mallocz(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:158
unsigned format_count
number of formats
Definition: formats.h:65
int * formats
list of media formats
Definition: formats.h:66