FFmpeg
utils.c
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 #include "config.h"
20 #include "avutil.h"
21 #include "avassert.h"
22 #include "samplefmt.h"
23 #include "internal.h"
24 
25 /**
26  * @file
27  * various utility functions
28  */
29 
30 #include "libavutil/ffversion.h"
31 const char av_util_ffversion[] = "FFmpeg version " FFMPEG_VERSION;
32 
33 const char *av_version_info(void)
34 {
35  return FFMPEG_VERSION;
36 }
37 
38 unsigned avutil_version(void)
39 {
44  av_assert0(HAVE_MMX2 == HAVE_MMXEXT);
45 
46  av_assert0(((size_t)-1) > 0); // C guarantees this but if false on a platform we care about revert at least b284e1ffe343d6697fb950d1ee517bafda8a9844
47 
48  if (av_sat_dadd32(1, 2) != 5) {
49  av_log(NULL, AV_LOG_FATAL, "Libavutil has been built with a broken binutils, please upgrade binutils and rebuild\n");
50  abort();
51  }
52 
53  if (llrint(1LL<<60) != 1LL<<60) {
54  av_log(NULL, AV_LOG_ERROR, "Libavutil has been linked to a broken llrint()\n");
55  }
56 
57  return LIBAVUTIL_VERSION_INT;
58 }
59 
60 const char *avutil_configuration(void)
61 {
62  return FFMPEG_CONFIGURATION;
63 }
64 
65 const char *avutil_license(void)
66 {
67 #define LICENSE_PREFIX "libavutil license: "
68  return &LICENSE_PREFIX FFMPEG_LICENSE[sizeof(LICENSE_PREFIX) - 1];
69 }
70 
71 const char *av_get_media_type_string(enum AVMediaType media_type)
72 {
73  switch (media_type) {
74  case AVMEDIA_TYPE_VIDEO: return "video";
75  case AVMEDIA_TYPE_AUDIO: return "audio";
76  case AVMEDIA_TYPE_DATA: return "data";
77  case AVMEDIA_TYPE_SUBTITLE: return "subtitle";
78  case AVMEDIA_TYPE_ATTACHMENT: return "attachment";
79  default: return NULL;
80  }
81 }
82 
84 {
85  switch (pict_type) {
86  case AV_PICTURE_TYPE_I: return 'I';
87  case AV_PICTURE_TYPE_P: return 'P';
88  case AV_PICTURE_TYPE_B: return 'B';
89  case AV_PICTURE_TYPE_S: return 'S';
90  case AV_PICTURE_TYPE_SI: return 'i';
91  case AV_PICTURE_TYPE_SP: return 'p';
92  case AV_PICTURE_TYPE_BI: return 'b';
93  default: return '?';
94  }
95 }
96 
97 unsigned av_int_list_length_for_size(unsigned elsize,
98  const void *list, uint64_t term)
99 {
100  unsigned i;
101 
102  if (!list)
103  return 0;
104 #define LIST_LENGTH(type) \
105  { type t = term, *l = (type *)list; for (i = 0; l[i] != t; i++); }
106  switch (elsize) {
107  case 1: LIST_LENGTH(uint8_t); break;
108  case 2: LIST_LENGTH(uint16_t); break;
109  case 4: LIST_LENGTH(uint32_t); break;
110  case 8: LIST_LENGTH(uint64_t); break;
111  default: av_assert0(!"valid element size");
112  }
113  return i;
114 }
115 
116 char *av_fourcc_make_string(char *buf, uint32_t fourcc)
117 {
118  int i;
119  char *orig_buf = buf;
120  size_t buf_size = AV_FOURCC_MAX_STRING_SIZE;
121 
122  for (i = 0; i < 4; i++) {
123  const int c = fourcc & 0xff;
124  const int print_chr = (c >= '0' && c <= '9') ||
125  (c >= 'a' && c <= 'z') ||
126  (c >= 'A' && c <= 'Z') ||
127  (c && strchr(". -_", c));
128  const int len = snprintf(buf, buf_size, print_chr ? "%c" : "[%d]", c);
129  if (len < 0)
130  break;
131  buf += len;
132  buf_size = buf_size > len ? buf_size - len : 0;
133  fourcc >>= 8;
134  }
135 
136  return orig_buf;
137 }
138 
140 {
141  return (AVRational){1, AV_TIME_BASE};
142 }
143 
144 void av_assert0_fpu(void) {
145 #if HAVE_MMX_INLINE
146  uint16_t state[14];
147  __asm__ volatile (
148  "fstenv %0 \n\t"
149  : "+m" (state)
150  :
151  : "memory"
152  );
153  av_assert0((state[4] & 3) == 3);
154 #endif
155 }
AVMEDIA_TYPE_SUBTITLE
@ AVMEDIA_TYPE_SUBTITLE
Definition: avutil.h:204
AVCodecParserContext::pict_type
int pict_type
Definition: avcodec.h:2783
AVPictureType
AVPictureType
Definition: avutil.h:272
av_sat_dadd32
#define av_sat_dadd32
Definition: common.h:129
av_version_info
const char * av_version_info(void)
Return an informative version string.
Definition: utils.c:33
state
static struct @319 state
AV_FOURCC_MAX_STRING_SIZE
#define AV_FOURCC_MAX_STRING_SIZE
Definition: avutil.h:346
LICENSE_PREFIX
#define LICENSE_PREFIX
samplefmt.h
av_assert0_fpu
void av_assert0_fpu(void)
Assert that floating point operations can be executed.
Definition: utils.c:144
avassert.h
avutil_version
unsigned avutil_version(void)
Return the LIBAVUTIL_VERSION_INT constant.
Definition: utils.c:38
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
av_assert0
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
av_int_list_length_for_size
unsigned av_int_list_length_for_size(unsigned elsize, const void *list, uint64_t term)
Compute the length of an integer list.
Definition: utils.c:97
AVMEDIA_TYPE_DATA
@ AVMEDIA_TYPE_DATA
Opaque data information usually continuous.
Definition: avutil.h:203
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
NULL
#define NULL
Definition: coverity.c:32
avutil_configuration
const char * avutil_configuration(void)
Return the libavutil build-time configuration.
Definition: utils.c:60
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AV_PICTURE_TYPE_SI
@ AV_PICTURE_TYPE_SI
Switching Intra.
Definition: avutil.h:278
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:274
list
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 list
Definition: filter_design.txt:25
AV_PICTURE_TYPE_SP
@ AV_PICTURE_TYPE_SP
Switching Predicted.
Definition: avutil.h:279
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
AVMediaType
AVMediaType
Definition: avutil.h:199
av_get_time_base_q
AVRational av_get_time_base_q(void)
Return the fractional representation of the internal time base.
Definition: utils.c:139
av_fourcc_make_string
char * av_fourcc_make_string(char *buf, uint32_t fourcc)
Fill the provided buffer with a string containing a FourCC (four-character code) representation.
Definition: utils.c:116
avutil_license
const char * avutil_license(void)
Return the libavutil license.
Definition: utils.c:65
LIST_LENGTH
#define LIST_LENGTH(type)
av_get_picture_type_char
char av_get_picture_type_char(enum AVPictureType pict_type)
Return a single letter to describe the given picture type pict_type.
Definition: utils.c:83
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
internal.h
AV_TIME_BASE
#define AV_TIME_BASE
Internal time base represented as integer.
Definition: avutil.h:254
AVMEDIA_TYPE_ATTACHMENT
@ AVMEDIA_TYPE_ATTACHMENT
Opaque data information usually sparse.
Definition: avutil.h:205
len
int len
Definition: vorbis_enc_data.h:426
AV_LOG_FATAL
#define AV_LOG_FATAL
Something went wrong and recovery is not possible.
Definition: log.h:174
__asm__
__asm__(".macro parse_r var r\n\t" "\\var = -1\n\t" _IFC_REG(0) _IFC_REG(1) _IFC_REG(2) _IFC_REG(3) _IFC_REG(4) _IFC_REG(5) _IFC_REG(6) _IFC_REG(7) _IFC_REG(8) _IFC_REG(9) _IFC_REG(10) _IFC_REG(11) _IFC_REG(12) _IFC_REG(13) _IFC_REG(14) _IFC_REG(15) _IFC_REG(16) _IFC_REG(17) _IFC_REG(18) _IFC_REG(19) _IFC_REG(20) _IFC_REG(21) _IFC_REG(22) _IFC_REG(23) _IFC_REG(24) _IFC_REG(25) _IFC_REG(26) _IFC_REG(27) _IFC_REG(28) _IFC_REG(29) _IFC_REG(30) _IFC_REG(31) ".iflt \\var\n\t" ".error \"Unable to parse register name \\r\"\n\t" ".endif\n\t" ".endm")
av_get_media_type_string
const char * av_get_media_type_string(enum AVMediaType media_type)
Return a string describing the media_type enum, NULL if media_type is unknown.
Definition: utils.c:71
AV_PICTURE_TYPE_B
@ AV_PICTURE_TYPE_B
Bi-dir predicted.
Definition: avutil.h:276
LIBAVUTIL_VERSION_MICRO
#define LIBAVUTIL_VERSION_MICRO
Definition: version.h:83
AV_SAMPLE_FMT_DBLP
@ AV_SAMPLE_FMT_DBLP
double, planar
Definition: samplefmt.h:70
AV_PICTURE_TYPE_P
@ AV_PICTURE_TYPE_P
Predicted.
Definition: avutil.h:275
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
avutil.h
llrint
#define llrint(x)
Definition: libm.h:394
AV_PICTURE_TYPE_BI
@ AV_PICTURE_TYPE_BI
BI type.
Definition: avutil.h:280
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AV_PICTURE_TYPE_S
@ AV_PICTURE_TYPE_S
S(GMC)-VOP MPEG-4.
Definition: avutil.h:277
fourcc
uint32_t fourcc
Definition: vaapi_decode.c:239
snprintf
#define snprintf
Definition: snprintf.h:34
av_util_ffversion
const char av_util_ffversion[]
Definition: utils.c:31