FFmpeg: libavutil/utils.c Source File

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libavutil

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 */

19 #include "config.h"

20 #include "avutil.h"

21 #include "avassert.h"

22 #include "samplefmt.h"

23 #include "internal.h"

25 /**

26 * @file

27 * various utility functions

28 */

30 #include "libavutil/ffversion.h"

31 const char av_util_ffversion[] = "FFmpeg version " FFMPEG_VERSION;

33 const char *av_version_info(void)

34 {

35 return FFMPEG_VERSION;

36 }

38 unsigned avutil_version(void)

39 {

40 av_assert0(AV_SAMPLE_FMT_DBLP == 9);

41 av_assert0(AVMEDIA_TYPE_ATTACHMENT == 4);

42 av_assert0(AV_PICTURE_TYPE_BI == 7);

43 av_assert0(LIBAVUTIL_VERSION_MICRO >= 100);

44 av_assert0(HAVE_MMX2 == HAVE_MMXEXT);

46 av_assert0(((size_t)-1) > 0); // C guarantees this but if false on a platform we care about revert at least b284e1ffe343d6697fb950d1ee517bafda8a9844

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 }

53 if (llrint(1LL<<60) != 1LL<<60) {

54 av_log(NULL, AV_LOG_ERROR, "Libavutil has been linked to a broken llrint()\n");

55 }

57 return LIBAVUTIL_VERSION_INT;

58 }

60 const char *avutil_configuration(void)

61 {

62 return FFMPEG_CONFIGURATION;

63 }

65 const char *avutil_license(void)

66 {

67 #define LICENSE_PREFIX "libavutil license: "

68 return &LICENSE_PREFIX FFMPEG_LICENSE[sizeof(LICENSE_PREFIX) - 1];

69 }

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 }

83 char av_get_picture_type_char(enum AVPictureType pict_type)

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 }

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

139 AVRational av_get_time_base_q(void)

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

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

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

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

state

static struct @320 state

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

#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