FFmpeg
options.c
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1 /*
2  * Copyright (c) 2001 Fabrice Bellard
3  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavcodec/options.c"
23 
25 {
26  //TODO: this code should set every possible pointer that could be set by codec and is not an option;
27  ctx->extradata_size = 8;
28  ctx->extradata = av_malloc(ctx->extradata_size);
29  return 0;
30 }
31 
33 {
34  av_freep(&ctx->extradata);
35  ctx->extradata_size = 0;
36  return 0;
37 }
38 
39 static int dummy_encode(AVCodecContext *ctx, AVPacket *pkt, const AVFrame *frame, int *got_packet)
40 {
41  return AVERROR(ENOSYS);
42 }
43 
44 typedef struct Dummy12Context {
46  int num;
47  char* str;
49 
50 typedef struct Dummy3Context {
52  int num;
53  char* str;
55 
56 #define OFFSET(x) offsetof(Dummy12Context, x)
57 #define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
58 static const AVOption dummy_options[] = {
59  { "str", "set str", OFFSET(str), AV_OPT_TYPE_STRING, { .str = "i'm src default value" }, 0, 0, VE},
60  { "num", "set num", OFFSET(num), AV_OPT_TYPE_INT, { .i64 = 1500100900 }, 0, INT_MAX, VE},
61  { NULL },
62 };
63 
64 static const AVClass dummy_v1_class = {
65  .class_name = "dummy_v1_class",
66  .item_name = av_default_item_name,
67  .option = dummy_options,
68  .version = LIBAVUTIL_VERSION_INT,
69 };
70 
71 static const AVClass dummy_v2_class = {
72  .class_name = "dummy_v2_class",
73  .item_name = av_default_item_name,
74  .option = dummy_options,
75  .version = LIBAVUTIL_VERSION_INT,
76 };
77 
78 /* codec with options */
80  .name = "dummy_v1_codec",
81  .type = AVMEDIA_TYPE_VIDEO,
82  .id = AV_CODEC_ID_NONE - 1,
83  .encode2 = dummy_encode,
84  .init = dummy_init,
85  .close = dummy_close,
86  .priv_class = &dummy_v1_class,
87  .priv_data_size = sizeof(Dummy12Context),
88 };
89 
90 /* codec with options, different class */
92  .name = "dummy_v2_codec",
93  .type = AVMEDIA_TYPE_VIDEO,
94  .id = AV_CODEC_ID_NONE - 2,
95  .encode2 = dummy_encode,
96  .init = dummy_init,
97  .close = dummy_close,
98  .priv_class = &dummy_v2_class,
99  .priv_data_size = sizeof(Dummy12Context),
100 };
101 
102 /* codec with priv data, but no class */
104  .name = "dummy_v3_codec",
105  .type = AVMEDIA_TYPE_VIDEO,
106  .id = AV_CODEC_ID_NONE - 3,
107  .encode2 = dummy_encode,
108  .init = dummy_init,
109  .close = dummy_close,
110  .priv_data_size = sizeof(Dummy3Context),
111 };
112 
113 /* codec without priv data */
115  .name = "dummy_v4_codec",
116  .type = AVMEDIA_TYPE_VIDEO,
117  .id = AV_CODEC_ID_NONE - 4,
118  .encode2 = dummy_encode,
119  .init = dummy_init,
120  .close = dummy_close,
121 };
122 
124 {
125  printf("%-14s: %dx%d prv: %s",
126  ctx->codec ? ctx->codec->name : "NULL",
127  ctx->width, ctx->height,
128  ctx->priv_data ? "set" : "null");
129  if (ctx->codec && ctx->codec->priv_class && ctx->codec->priv_data_size) {
130  int64_t i64;
131  char *str = NULL;
132  av_opt_get_int(ctx->priv_data, "num", 0, &i64);
133  av_opt_get(ctx->priv_data, "str", 0, (uint8_t**)&str);
134  printf(" opts: %"PRId64" %s", i64, str);
135  av_free(str);
136  }
137  printf("\n");
138 }
139 
140 static void test_copy(const AVCodec *c1, const AVCodec *c2)
141 {
142  AVCodecContext *ctx1, *ctx2;
143  printf("%s -> %s\nclosed:\n", c1 ? c1->name : "NULL", c2 ? c2->name : "NULL");
144  ctx1 = avcodec_alloc_context3(c1);
145  ctx2 = avcodec_alloc_context3(c2);
146  ctx1->width = ctx1->height = 128;
147  ctx1->time_base = (AVRational){12,34};
148  if (ctx2->codec && ctx2->codec->priv_class && ctx2->codec->priv_data_size) {
149  av_opt_set(ctx2->priv_data, "num", "667", 0);
150  av_opt_set(ctx2->priv_data, "str", "i'm dest value before copy", 0);
151  }
152  avcodec_copy_context(ctx2, ctx1);
153  test_copy_print_codec(ctx1);
154  test_copy_print_codec(ctx2);
155  if (ctx1->codec) {
156  int ret;
157  printf("opened:\n");
158  ret = avcodec_open2(ctx1, ctx1->codec, NULL);
159  if (ret < 0) {
160  fprintf(stderr, "avcodec_open2 failed\n");
161  exit(1);
162  }
163  if (ctx2->codec && ctx2->codec->priv_class && ctx2->codec->priv_data_size) {
164  av_opt_set(ctx2->priv_data, "num", "667", 0);
165  av_opt_set(ctx2->priv_data, "str", "i'm dest value before copy", 0);
166  }
167  avcodec_copy_context(ctx2, ctx1);
168  test_copy_print_codec(ctx1);
169  test_copy_print_codec(ctx2);
170  avcodec_close(ctx1);
171  }
172  avcodec_free_context(&ctx1);
173  avcodec_free_context(&ctx2);
174 }
175 
176 int main(void)
177 {
178  AVCodec *dummy_codec[] = {
183  NULL,
184  };
185  int i, j;
186 
187  for (i = 0; dummy_codec[i]; i++)
188  avcodec_register(dummy_codec[i]);
189 
190  printf("testing avcodec_copy_context()\n");
191  for (i = 0; i < FF_ARRAY_ELEMS(dummy_codec); i++)
192  for (j = 0; j < FF_ARRAY_ELEMS(dummy_codec); j++)
193  test_copy(dummy_codec[i], dummy_codec[j]);
194  return 0;
195 }
#define NULL
Definition: coverity.c:32
const struct AVCodec * codec
Definition: avcodec.h:1577
int main(void)
Definition: options.c:176
static AVCodec dummy_v3_encoder
Definition: options.c:103
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
AVOption.
Definition: opt.h:246
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
char * str
Definition: options.c:53
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:191
static void test_copy(const AVCodec *c1, const AVCodec *c2)
Definition: options.c:140
static AVPacket pkt
AVCodec.
Definition: avcodec.h:3492
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avcodec.h:1691
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
uint8_t
#define av_malloc(s)
static AVCodec dummy_v1_encoder
Definition: options.c:79
AVClass * av_class
Definition: options.c:45
void * fake_av_class
Definition: options.c:51
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1669
static const uint64_t c1
Definition: murmur3.c:49
av_cold void avcodec_register(AVCodec *codec)
Register the codec codec and initialize libavcodec.
Definition: allcodecs.c:837
static int dummy_init(AVCodecContext *ctx)
Definition: options.c:24
int avcodec_close(AVCodecContext *avctx)
Close a given AVCodecContext and free all the data associated with it (but not the AVCodecContext its...
Definition: utils.c:1095
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
char * str
Definition: options.c:47
const char * name
Name of the codec implementation.
Definition: avcodec.h:3499
static void test_copy_print_codec(const AVCodecContext *ctx)
Definition: options.c:123
static const AVClass dummy_v1_class
Definition: options.c:64
int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src)
Copy the settings of the source AVCodecContext into the destination AVCodecContext.
Definition: options.c:215
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:156
#define OFFSET(x)
Definition: options.c:56
int width
picture width / height.
Definition: avcodec.h:1741
int priv_data_size
Definition: avcodec.h:3540
static const AVOption dummy_options[]
Definition: options.c:58
AVFormatContext * ctx
Definition: movenc.c:48
static const AVClass dummy_v2_class
Definition: options.c:71
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 the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
static AVCodec dummy_v2_encoder
Definition: options.c:91
#define FF_ARRAY_ELEMS(a)
int av_opt_get_int(void *obj, const char *name, int search_flags, int64_t *out_val)
Definition: opt.c:888
void avcodec_free_context(AVCodecContext **pavctx)
Free the codec context and everything associated with it and write NULL to the provided pointer...
Definition: options.c:171
main external API structure.
Definition: avcodec.h:1568
int extradata_size
Definition: avcodec.h:1670
Describe the class of an AVClass context structure.
Definition: log.h:67
#define VE
Definition: options.c:57
Rational number (pair of numerator and denominator).
Definition: rational.h:58
static int dummy_close(AVCodecContext *ctx)
Definition: options.c:32
int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
Definition: utils.c:548
const AVClass * priv_class
AVClass for the private context.
Definition: avcodec.h:3518
static const uint64_t c2
Definition: murmur3.c:50
static AVCodec dummy_v4_encoder
Definition: options.c:114
void * priv_data
Definition: avcodec.h:1595
int av_opt_get(void *obj, const char *name, int search_flags, uint8_t **out_val)
Definition: opt.c:761
#define av_free(p)
printf("static const uint8_t my_array[100] = {\n")
Options definition for AVCodecContext.
#define av_freep(p)
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
This structure stores compressed data.
Definition: avcodec.h:1457
int av_opt_set(void *obj, const char *name, const char *val, int search_flags)
Definition: opt.c:449
static int dummy_encode(AVCodecContext *ctx, AVPacket *pkt, const AVFrame *frame, int *got_packet)
Definition: options.c:39