FFmpeg
vf_format.c
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1 /*
2  * Copyright (c) 2007 Bobby Bingham
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  * format and noformat video filters
24  */
25 
26 #include <string.h>
27 
28 #include "libavutil/internal.h"
29 #include "libavutil/mem.h"
30 #include "libavutil/pixdesc.h"
31 #include "libavutil/opt.h"
32 
33 #include "avfilter.h"
34 #include "formats.h"
35 #include "internal.h"
36 #include "video.h"
37 
38 typedef struct FormatContext {
39  const AVClass *class;
40  char *pix_fmts;
41 
42  /**
43  * pix_fmts parsed into AVPixelFormats and terminated with
44  * AV_PIX_FMT_NONE
45  */
48 
50 {
51  FormatContext *s = ctx->priv;
52  av_freep(&s->formats);
53 }
54 
56 {
57  FormatContext *s = ctx->priv;
58  char *cur, *sep;
59  int nb_formats = 1;
60  int i;
61  int ret;
62 
63  if (!s->pix_fmts) {
64  av_log(ctx, AV_LOG_ERROR, "Empty output format string.\n");
65  return AVERROR(EINVAL);
66  }
67 
68  /* count the formats */
69  cur = s->pix_fmts;
70  while ((cur = strchr(cur, '|'))) {
71  nb_formats++;
72  if (*cur)
73  cur++;
74  }
75 
76  s->formats = av_malloc_array(nb_formats + 1, sizeof(*s->formats));
77  if (!s->formats)
78  return AVERROR(ENOMEM);
79 
80  /* parse the list of formats */
81  cur = s->pix_fmts;
82  for (i = 0; i < nb_formats; i++) {
83  sep = strchr(cur, '|');
84  if (sep)
85  *sep++ = 0;
86 
87  if ((ret = ff_parse_pixel_format(&s->formats[i], cur, ctx)) < 0)
88  return ret;
89 
90  cur = sep;
91  }
92  s->formats[nb_formats] = AV_PIX_FMT_NONE;
93 
94  if (!strcmp(ctx->filter->name, "noformat")) {
95  const AVPixFmtDescriptor *desc = NULL;
96  enum AVPixelFormat *formats_allowed;
97  int nb_formats_lavu = 0, nb_formats_allowed = 0;
98 
99  /* count the formats known to lavu */
100  while ((desc = av_pix_fmt_desc_next(desc)))
101  nb_formats_lavu++;
102 
103  formats_allowed = av_malloc_array(nb_formats_lavu + 1, sizeof(*formats_allowed));
104  if (!formats_allowed)
105  return AVERROR(ENOMEM);
106 
107  /* for each format known to lavu, check if it's in the list of
108  * forbidden formats */
109  while ((desc = av_pix_fmt_desc_next(desc))) {
111 
112  for (i = 0; i < nb_formats; i++) {
113  if (s->formats[i] == pix_fmt)
114  break;
115  }
116  if (i < nb_formats)
117  continue;
118 
119  formats_allowed[nb_formats_allowed++] = pix_fmt;
120  }
121  formats_allowed[nb_formats_allowed] = AV_PIX_FMT_NONE;
122  av_freep(&s->formats);
123  s->formats = formats_allowed;
124  }
125 
126  return 0;
127 }
128 
130 {
131  FormatContext *s = ctx->priv;
133 
134  if (!formats)
135  return AVERROR(ENOMEM);
136 
137  return ff_set_common_formats(ctx, formats);
138 }
139 
140 
141 #define OFFSET(x) offsetof(FormatContext, x)
142 static const AVOption options[] = {
143  { "pix_fmts", "A '|'-separated list of pixel formats", OFFSET(pix_fmts), AV_OPT_TYPE_STRING, .flags = AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_FILTERING_PARAM },
144  { NULL }
145 };
146 
147 #if CONFIG_FORMAT_FILTER
148 
149 #define format_options options
151 
152 static const AVFilterPad avfilter_vf_format_inputs[] = {
153  {
154  .name = "default",
155  .type = AVMEDIA_TYPE_VIDEO,
156  .get_video_buffer = ff_null_get_video_buffer,
157  },
158  { NULL }
159 };
160 
161 static const AVFilterPad avfilter_vf_format_outputs[] = {
162  {
163  .name = "default",
164  .type = AVMEDIA_TYPE_VIDEO
165  },
166  { NULL }
167 };
168 
170  .name = "format",
171  .description = NULL_IF_CONFIG_SMALL("Convert the input video to one of the specified pixel formats."),
172 
173  .init = init,
174  .uninit = uninit,
175 
176  .query_formats = query_formats,
177 
178  .priv_size = sizeof(FormatContext),
179  .priv_class = &format_class,
180 
181  .inputs = avfilter_vf_format_inputs,
182  .outputs = avfilter_vf_format_outputs,
183 };
184 #endif /* CONFIG_FORMAT_FILTER */
185 
186 #if CONFIG_NOFORMAT_FILTER
187 
188 #define noformat_options options
189 AVFILTER_DEFINE_CLASS(noformat);
190 
191 static const AVFilterPad avfilter_vf_noformat_inputs[] = {
192  {
193  .name = "default",
194  .type = AVMEDIA_TYPE_VIDEO,
195  .get_video_buffer = ff_null_get_video_buffer,
196  },
197  { NULL }
198 };
199 
200 static const AVFilterPad avfilter_vf_noformat_outputs[] = {
201  {
202  .name = "default",
203  .type = AVMEDIA_TYPE_VIDEO
204  },
205  { NULL }
206 };
207 
209  .name = "noformat",
210  .description = NULL_IF_CONFIG_SMALL("Force libavfilter not to use any of the specified pixel formats for the input to the next filter."),
211 
212  .init = init,
213  .uninit = uninit,
214 
215  .query_formats = query_formats,
216 
217  .priv_size = sizeof(FormatContext),
218  .priv_class = &noformat_class,
219 
220  .inputs = avfilter_vf_noformat_inputs,
221  .outputs = avfilter_vf_noformat_outputs,
222 };
223 #endif /* CONFIG_NOFORMAT_FILTER */
#define NULL
Definition: coverity.c:32
static enum AVPixelFormat pix_fmt
AVOption.
Definition: opt.h:246
int ff_parse_pixel_format(enum AVPixelFormat *ret, const char *arg, void *log_ctx)
Parse a pixel format.
Definition: formats.c:609
Main libavfilter public API header.
Memory handling functions.
const char * desc
Definition: nvenc.c:68
AVFrame * ff_null_get_video_buffer(AVFilterLink *link, int w, int h)
Definition: video.c:39
#define OFFSET(x)
Definition: vf_format.c:141
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample format(the sample packing is implied by the sample format) and sample rate.The lists are not just lists
AVFilterFormats * ff_make_format_list(const int *fmts)
Create a list of supported formats.
Definition: formats.c:283
const char * name
Pad name.
Definition: internal.h:60
#define av_cold
Definition: attributes.h:82
AVOptions.
#define av_log(a,...)
A filter pad used for either input or output.
Definition: internal.h:54
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
int ff_set_common_formats(AVFilterContext *ctx, AVFilterFormats *formats)
A helper for query_formats() which sets all links to the same list of formats.
Definition: formats.c:568
#define AV_OPT_FLAG_FILTERING_PARAM
a generic parameter which can be set by the user for filtering
Definition: opt.h:291
static int query_formats(AVFilterContext *ctx)
Definition: vf_format.c:129
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
void * priv
private data for use by the filter
Definition: avfilter.h:353
char * pix_fmts
Definition: vf_format.c:40
common internal API header
enum AVPixelFormat av_pix_fmt_desc_get_id(const AVPixFmtDescriptor *desc)
Definition: pixdesc.c:2541
AVFilter ff_vf_noformat
static av_cold int init(AVFilterContext *ctx)
Definition: vf_format.c:55
static av_cold void uninit(AVFilterContext *ctx)
Definition: vf_format.c:49
enum AVPixelFormat * formats
pix_fmts parsed into AVPixelFormats and terminated with AV_PIX_FMT_NONE
Definition: vf_format.c:46
AVFormatContext * ctx
Definition: movenc.c:48
#define s(width, name)
Definition: cbs_vp9.c:257
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
static const AVOption options[]
Definition: vf_format.c:142
Descriptor that unambiguously describes how the bits of a pixel are stored in the up to 4 data planes...
Definition: pixdesc.h:81
#define AV_OPT_FLAG_VIDEO_PARAM
Definition: opt.h:279
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several inputs
Describe the class of an AVClass context structure.
Definition: log.h:67
Filter definition.
Definition: avfilter.h:144
const char * name
Filter name.
Definition: avfilter.h:148
AVFilter ff_vf_format
#define AVFILTER_DEFINE_CLASS(fname)
Definition: internal.h:334
A list of supported formats for one end of a filter link.
Definition: formats.h:64
An instance of a filter.
Definition: avfilter.h:338
#define av_freep(p)
#define av_malloc_array(a, b)
formats
Definition: signature.h:48
internal API functions
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
const AVFilter * filter
the AVFilter of which this is an instance
Definition: avfilter.h:341
const AVPixFmtDescriptor * av_pix_fmt_desc_next(const AVPixFmtDescriptor *prev)
Iterate over all pixel format descriptors known to libavutil.
Definition: pixdesc.c:2529